Device for guided needle placement

Abstract

The present disclosure provides a device for imaging guided placement of a needle or other tissue penetrating instrument. In certain embodiments, the device comprises a guide body comprising an MRI visible material and defining an elongate passageway configured to receive and guide a shaft of a needle or other tissue penetrating instrument along an axis for insertion into a patient.

Description

[0001] Device for Guided Needle Placement

[0002] BACKGROUND

[0003] The present invention relates generally to medical technology and in particular aspects to devices that are useful aides in the guided, preferably magnetic resonance imaging (MRI) guided, insertion of tissue penetrating instruments, such as needles, into patients.

[0004] As further background, many medical procedures involve the insertion of an instrument such as a needle into patient tissue, oftentimes while guided by an imaging modality such as MRI. As examples, such procedures can be performed to obtain a tissue biopsy. Achieving a desired entry point and insertion path for a needle can often be difficult. Current approaches typically only indicate an access point on the skin, without aligning the correct trajectory to the target anatomy prior to entry. In addition, needles are typically constructed of materials such as stainless steel or other metals that are not typically visible on MRI scans when located external of the patient. Known approaches to aid in needle insertion include: laser indicating systems, whereby the intersection of a series of laser sheets are used to illuminate an entry point on the skin, marking the target entry point in skin with MRI-visible ink, and the "finger poke" method whereby deformation in tissue caused by a physician's finger probing the skin surrounding a proposed entry point is tracked under live MRI imaging.

[0005] There remain needs for improved and / or alternative devices and methods for guided needle placement. In certain aspects, embodiments of the present disclosure are addressed to these needs.

[0006] SUMMARY

[0007] In accordance with some embodiments of the disclosure, provided are guide devices useful for guided insertion of a tissue penetrating instrument, such as a needle, into patient tissue. Accordingly, in one embodiment, the present disclosure provides a guide device for magnetic resonance imaging (MRI) guided placement of a needle, the device comprising a guide body comprising an MRI visible material and defining an elongate passageway configured to receive and guide a needle shaft along an axis for insertion into a patient. In some forms, the passageway is a groove extending along a side wall of the guide body. The groove can have a bottom wall surface for receipt against a sidewall surface of the needle shaft to guide the needle shaft. The bottom wall can define a bottom wall surface, wherein the bottom wall surface is contoured to conform to a portion of a circumference of the needle shaft. In some forms, the guide body defines an internal chamber, and the MRI visible material is received within the internal chamber. In variants in which the passageway comprises a groove, the groove can have a first segment having a first depth and a second segment having a second depth different from the first depth, wherein the second depth is less than the first depth. In certain embodiments, the second depth is less than the diameter of the needle. Such a groove can also have a third segment, with the second segment positioned between the first segment and the third segment, and wherein the third segment has a third depth greater than the second depth. The guide body may also comprise a tapered distal end, for example configured to contact skin of the patient. In certain embodiments, the groove or other passageway is configured in the guide body such that when present therein, a needle shaft is only partially circumferentially surrounded by

[0008] MRI visible material. In some forms the device also comprises a mechanical actuator arranged to engage and move the needle along the axis. Aspects of the present disclosure also provide combinations comprising a guide device as disclosed herein and a tissue penetrating instrument such as a needle having a body receivable in the passageway.

[0009] In another embodiment, the present disclosure provides a method of MRI assisted placement of a needle into patient tissue. The method comprises visualizing under MRI a guide body comprising an MRI visible material, the guide body defining an elongate passageway configured to receive and guide a needle shaft along an axis for insertion into a patient, and wherein a needle is received within the elongate passageway, positioning the axis along a target path, the target path being pre-selected to intersect with a target region of patient tissue, inserting the needle at least partially into patient tissue along the target path, and removing the guide body from the needle while the needle is at least partially inserted into patient tissue. In certain embodiments the method includes inserting the needle to the target region after said removing of the guide body. In some forms of practicing the disclosed methods the visualizing step comprises utilizing biplanar MRI to visualize the target path in a first plane and a second plane, and wherein said positioning comprises positioning the axis along the target path in each of the first plane and the second plane. in other embodiments, provided are devices for guided placement of a needle. In certain embodiments, such devices comprise a guide body defining an elongate passageway configured to receive and guide a shaft of a tissue penetrating instrument along an axis for insertion into a patient. The guide body may include a plurality of guide body portions that are reversibly arrangeable relative to one another to constitute the elongate passageway in a closed position or deconstitute the elongate passageway in an open position. In some forms, the guide body portions include a first guide body portion defining an elongate first groove and a second guide body portion defining an elongate second groove. In certain embodiments, the first guide portion is movably connected to the second guide body. For example, the first guide body portion may be hingedly connected to the second guide body portion. The first guide body portion and the second guide body portion may be pivotable relative to one another from the open position to the closed position such that in the closed position the first groove and the second groove are brought together to constitute the elongate passageway. In some forms, with the plurality of guide body portions arranged to constitute the elongate passageway, the guide body also defines a cavity positioned along the elongate passageway and configured to receive a stabilizing member. The stabilizing member may be friction fitted around and slidable relative to the shaft of the tissue penetrating member. In certain embodiments, at least one of the plurality of guide body portions comprise an MRI visible material. For example, in some forms, a first guide body portion defines a first inner chamber, and wherein an MRI visible material is received within the first inner chamber. In addition, or alternatively, a second guide body portion defines a second inner chamber, and wherein an MRI visible material is received within the second inner chamber. In certain embodiments, the guide body comprises a tapered distal end with the plurality of guide body portions arranged to constitute the elongate passageway. In some forms, a proximal end of each of the plurality of guide body portions comprises a respective capping member, the capping members may be configured to together define a portion of the elongate passageway with the plurality of guide body portions arranged to constitute the elongate passageway. The tissue penetrating member may comprise a needle. In some forms, one or more of the guide body portions comprise a gripping tab, preferably the guide body comprises at least a first gripping tab and a second gripping tab.

[0010] In some forms, when the plurality of guide body portions are arranged to constitute the elongate passageway, the first gripping tab and second gripping tab are spaced from one another and are movable toward one another to deconstitute the elongate passageway. In accordance with some forms, wherein the first guide body portion and the second guide body portion are configured with stop surfaces that limit their pivotable motion relative to one another between the closed position and the open position. For example, the pivotable motion may be limited to about 90 degrees or less, or about 60 degrees or less, between the open position and the closed position.

[0011] In another embodiment, the present disclosure provides methods of MRI guidance comprising positioning a device as detailed herein by aligning the device with elongate passageway of the device with a target path through patient tissue with the plurality of guide portions arranged to constitute the elongate passageway. In some forms, during the positioning step a shaft of a tissue penetrating instrument is received in the elongate passageway. The method may also comprise inserting the tissue penetrating instrument at least partially into patient tissue along the target path. In some forms, the method includes removing the device from the tissue penetrating instrument while the instrument is at least partially inserted into patient tissue. Removing the device may include the step of moving the plurality of guide body portions relative to one another to deconstitute the elongate passageway.

[0012] The present disclosure also provides methods for preparing a device for guided placement of a tissue penetrating instrument. Such methods may indude the step of loading a tissue penetrating instrument into the passageway of a device as taught herein. In certain embodiments, the method comprises positioning a stabilizing member on the tissue penetrating instrument prior to loading the tissue penetrating instrument into the passageway. The stabilizing member may be positionable within a cavity along the passageway. In accordance with some forms, the loading step is performed with the device in the open position. For example, the tissue penetrating member may be positioned in the first or second groove. In certain embodiments, the method includes the step ofclosing the guide body to constitute the elongate passageway around at least a portion of the tissue penetrating instrument.

[0013] Still further embodiments, as well as features and advantages of embodiments described herein, will be apparent to persons skilled in the relevant field from the descriptions herein.

[0014] BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1a is a side view of one embodiment of a device as disclosed herein.

[0016] Figure 1b is a partial cutaway side view of one embodiment of a device as disclosed herein.

[0017] Figure 1c is a side view of one embodiment of a device as disclosed herein.

[0018] Figure 1d is a top-down view of one embodiment of a device as disclosed herein.

[0019] Figure 2a is a side view of one embodiment of a device as disclosed herein.

[0020] Figure 2b is a side view of one embodiment of a device as disclosed herein.

[0021] Figure 3 is a cross-sectional view along line 300 of Figure la.

[0022] Figure 4a is a side view of one embodiment of a device as disclosed herein.

[0023] Figure 4b is a side view of one embodiment of a device as disclosed herein.

[0024] Figure 5A-5D are MRI images illustrating steps in one embodiment of using a device as disclosed herein.

[0025] Figure 6 is a cross-sectional view along line 300 of Figure la.

[0026] Figure 7A is a side view of one embodiment of a device as disclosed herein.

[0027] Figure 7B is a side view of one embodiment of a device as disclosed herein.

[0028] Figure 8A is a top-down view of one embodiment of a device as disclosed herein.

[0029] Figure 8B is a top-down view of one embodiment of a device as disclosed herein.

[0030] Figure 9 is a side view of one embodiment of a component of a device as disclosed herein.

[0031] Figure 10 is a side view of one embodiment of a component of a device as disclosed herein.

[0032] Figure 11A is a perspective view of a depth stop as disclosed herein.

[0033] Figure 11B is a top-down view of a depth stop as disclosed herein.

[0034] Figure 12 is a partial side view of a portion of one embodiment of a device as disclosed herein.

[0035] Figure 13 is a perspective cutaway view of one embodiment of a device as disclosed herein.

[0036] Figure 14 is a side view of one embodiment of a device as disclosed herein.

[0037] Figure 15 is a top-down view of one embodiment of a device as disclosed herein.

[0038] Figure 16A is a perspective of one embodiment of a component of a device as disclosed herein. Figure 16B is a bottom-up view of the component of figure 16A.

[0039] Figure 17A is a perspective of one embodiment of a component of a device as disclosed herein.

[0040] Figure 17B is a bottom-up view of the component of figure 17A.

[0041] Figure 18A is a perspective of one embodiment of a component of a device as disclosed herein.

[0042] Figure 18B is a bottom-up view of the component of figure 18A.

[0043] DETAILED DESCRIPTION

[0044] Reference will now be made to certain embodiments, some of which are illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications in the described embodiments and any further applications of the principles as described herein are contemplated as would normally occur to one skilled in the art to which this disclosure relates.

[0045] As disclosed above, aspects of the present disclosure relate to guide devices useful for guided placement, preferably magnetic resonance imaging (MRI) guided placement, of a needle or other tissue penetrating instrument. In this regard, while certain disclosures below and elsewhere herein discuss the placement of a needle, it will be understood that such disclosures can also apply to the placement of other tissue penetrating instruments configured for penetration into and through patient tissue. The needle or other tissue penetrating instrument can, for example, be configured for use in an in-bore procedure, such as a biopsy of patient tissue, and / or for administering a diagnostic or therapeutic substance to patient tissue, which may for example be a liquid substance, through a lumen thereof.

[0046] Consistent with the discussions above, certain embodiments of the present disclosure provide a device comprising an MRI visible material and capable of indicating both position and orientation of a needle under imaging prior to entry into patient tissue. In accordance with some forms, the device is configured for use with a needle, such as a coaxial needle. In accordance with some forms, the needle is a biopsy needle. The device may be configured to physically guide the needle along a guide axis before and after entry of a portion of the needle into patient tissue.

[0047] In accordance with some forms, devices of the present disclosure include a guide body. The guide body is preferably elongate, extending from a proximal end to a distal end. In certain embodiments, the distal end of the guide body is configured for contact with patient tissue. In some forms, the guide body comprises an MRI visible material. As used herein, the term "MRI visible material" means any material capable of emitting a signal imageable by an MRI machine. In accordance with some forms, the guide body comprises an internal chamber. An MRI visible material, which can be a liquid, may be positioned in the internal chamber of the guide body. In some forms, the guide body comprises a proximal end opening into the internal chamber. The guide body can further comprise a capping member sealing the opening and configured to prevent escape of the MRI visible material from the internal chamber. When present, the capping member may include a notch that may form a portion of the needle-guiding passageway of the device. In other embodiments, the guide body or portions thereof may be formed from an MRI visible material, for example a solid polymeric material that is itself MRI visible or that is doped with an MRI visible material.

[0048] Suitable MRI visible materials include aqueous media containing paramagnetic materials such as platinum, nickel, manganese, copper sulfate, sodium chloride, gadolinium chloride, and / or an oil (e.g. fish oil and / or vegetable oil). In some forms, the MRI visible material comprises an emulsifier such as glycerol monostearate, magnesium stearate, and / or glyceryl hydroxystearate. In certain embodiments, the MRI visible material comprises a solid or semi-solid medium containing polyvinyl alcohol, wax, polyacrylic acid, silicon, gelatin, or agarose. In certain embodiments an MRI visible material may contain a salt, such as sodium chloride, nickel sulfate, thulium nitrate, to modify its T1 or T2 relaxation time under magnetic resonance. In any of the embodiments described herein, the MRI visible material may comprise any liquid, gel, solid, or semi-solid material with response under MRI configured to provide contrast and thereby render visible all, a selected portion, or selected portions, of the guide device in the image generated by MRI, for example when positioned external of the patient in the gaseous environment (e.g. air) surrounding the patient.

[0049] In certain embodiments, the guide body of a device comprises a tapered end. In some forms, the distal end of the device, e.g. configured for contact with skin of the patient, is tapered. In accordance with some forms, the device is configured such that the taper of the tapered end is visible and identifiable under MRI visualization. In such forms, the guide body can incorporate the MRI visible material in a tapered shape. For example, when present, an internal chamber containing an MRI visible material can have a tapered chamber region that extends into the tapered end of the guide body. The distal end of the guide body may also comprise a blunt tip for pressing against patient tissue. Such blunt tip devices may be advantageously pressed against and thereby indent patient tissue to further aid in localization under MRI visualization. As noted above, a guide body of the present disclosure can be configured to guide movement of a needle along an axis for insertion into a patient. In accordance with some forms, the MRI equipment displays an image showing a target line or path through patient tissue to assist the operator in inserting the needle into a target tissue region. For example, a displayed biplanar MRI image may include a target line formed at the intersection of two imaging planes. In some modes of use, the device as disclosed herein is oriented to align the guide axis of the groove or other guide passageway thereof with the displayed target line through patient tissue to the target tissue region. For instance, a user may align the guide axis with the target line as displayed in first and second imaging planes. This may be done by first aligning the guide axis with the target line displayed in a first plane, and then while maintaining alignment in the first plane, align the guide axis with the target line in the second plane. After alignment of the guide axis with the target line, the needle can be advanced along the guide axis of the guiding device and into tissue of the patient. Where the needle or portions thereof (e.g. discrete MRI markers thereof) is / are visible in the MRI- generated image when received in patient tissue, the user can track the progress of the needle along the target line displayed in the MRI image.

[0050] As disclosed herein, the guide body defines a passageway configured to receive a needle or other elongate tissue penetrating device. In accordance with some forms, the passageway comprises a groove extending into the guide body such that the passageway is partially circumferentially surrounded by MRI visible material. In some forms, the groove comprises an open side extending the length of the groove. In this manner, the guide body can be separated from the needle by movement in a direction transverse (e.g. perpendicular) to the guide axis defined by the groove. The groove or other passageway may be sized to accommodate any suitable needle type, diameter or length. In some forms, the groove comprises a portion having a consistent width extending into the groove.

[0051] Additionally, or alternatively, a groove provided in the guide body may comprise a tapered wall portion, wherein at least a portion of the groove narrows in a direction toward a bottom wall surface of the groove to facilitate placement of a needle shaft within the groove. Thus, the groove may comprise a first tapered portion, wherein the opposing groove walls converge, and a second portion wherein the opposing groove walls are parallel. In some forms, the groove walls can be configured to snap over the needle shaft, such that the needle shaft is secured within the groove and a force must be exerted to snap the needle into or out of the groove. One or more flexing detent portions may be incorporated into the groove structure for these purposes. In addition, or alternatively, a material forming a surface of the groove for contact with the needle shaft may provide a friction fit with the needle shaft that resists axial movement of the needle along the groove until overcome by force manually or mechanically applied to the needle shaft (e.g. by a hand of a user or by an actuator as disclosed herein). In accordance with preferred forms, the guide body may be configured such that the guide axis thereof is visibly marked in an MRI image of the guide device, even without the presence of a needle or other instrument in the passageway thereof. Such a visible marking may be continuous along the entire or a portion of the length of the groove or other passageway, and in some forms may result from the presence of an MRI visible material laterally flanking first and second sides of the groove or other passageway in an MRI image plane taken through the guide body, where the groove or other passageway has less or none of the MRI visible material. In some forms, the guide body is configured to be imaged by MRI in a plane having first and second regions of MRI visible material flanking the passageway and the passageway is free of or has less of the MRI visible material in said plane, such that the passageway is visually contrasted to the regions.

[0052] In alternative embodiments, the guide body may be configured such that the guide axis defined thereby is not visibly marked in an MRI image absent a needle or other instrument received in the groove or other guide passageway, but the MRI visible material of the guide body provides a contrasting background in an MRI Image such that an MRI visible needle shaft or needle shaft portion(s) received in the groove or other guide passageway provides a marking aligned with the guide axis. These and other arrangements for the guiding device, and uses thereof with a needle or other instrument, will be apparent from the descriptions herein.

[0053] A guide body herein may be configured in any suitable size and shape. In accordance with some forms the guide body has a maximum width of 5mm to 50mm, preferably 10mm to 40mm, more preferably 12mm to 35mm. In accordance with some forms the guide body has a length of 75mm to 200mm, preferably 90mm to 175mm, more preferably 100mm to

[0054] 150mm. As disclosed herein, the depth of a groove may vary along the length of the guide body. With reference to Figure 6, in the present description, the depth 162 of a groove at a given location is measured by means of three planes "a", "b" and "c" . Plane "a" is a plane intersecting the groove bottom; said plane "a” being perpendicular to a plane "b ” tangent to the groove bottom and to a plane "c" which is parallel to "b" and substantially closes the groove on the top. Thus, the depth 162 of a groove at a given point is given by the distance, measured on plane "a", between the intersecting line of planes "a" and "b" and the intersecting line of planes "a" and "c". In accordance with some forms, the groove has a maximum depth (e.g. outside of a portion configured to allow for manual contact with a needle positioned in the groove) of 4mm to 20mm, preferably 6mm to 18mm, more preferably 8mm to 16mm. In certain embodiments the groove depth may comprise at least

[0055] 25% of the maximum width of the guide body, preferably at least 40% of the maximum width of the guide body, even more preferably at least 50% of the maximum width of the guide body.

[0056] The guide body herein may have any suitable volumetric shape. In certain embodiments, the guide body is an elongate guide body, for example having a cylindrical or semi-cylindrical shaped portion. In accordance with some forms, the guide body may comprise a generally rounded outer surface. In some forms, the guide body may comprise a faceted, flat wall portion of the outer surface. Such a flat wall portion may be useful to allow the user to locate the groove or other passageway, opening at the flat wall portion, by touch so as to more easily insert a needle into the passageway, or to remove the guide body from a needle. In certain embodiments the flat wall portion extends the length of the guide body, from the proximal end to the distal end. In another embodiment, the flat wall portion extends only a portion of the length of the guide body.

[0057] In accordance with some forms, the guide body may comprise a contact portion in which the needle, within the passageway, is exposed to contact by a user's hand. In accordance with some forms, the contact portion comprises a recess in the guide body such that the passageway in the contact area is exposed for such contact. In one form, the depth of a groove, from a surface immediately adjacent the groove to the bottom wall of the groove, is less within a segment of the groove providing the contact portion than in one or more other segments of the groove. Such a configuration allows the user to controllably retain the needle within the passageway by applying pressure directly to the needle shaft

[0058] (e.g. by contact with a thumb or other digit of the user's hand) within the contact portion while grasping the device by hand. Optionally, a user may use a thumb and / or finger(s) to grasp the device, while an index finger is used to advance the needle so as to move the tip of the needle distally beyond the distal end of the device. In such configurations, the contact portion can be positioned such that an index finger of a user's hand is able to reach the proximal end of the needle while other digit(s) (e.g. thumb and / or fingers) of that hand contact and apply pressure to the needle within the contact portion of the device. Such a configuration advantageously provides for operation of the device with a single hand, a feature beneficial when working in the confined environment of MRI procedures.

[0059] In accordance with some forms, the device is adapted for use with a needle. Any suitable needle may be used. Of particular advantage are needles comprising an MRI visible material. Examples of the needles which may be suitable for use comprise: a fine needle aspiration (FNA) needle, a trocar needle, a Franseen needle, and / or core biopsy needles. In accordance with some forms, the needle extends from a proximal end to a distal end. In certain embodiments, the proximal end of the needle comprises a needle hub. The length of the guide body, from the proximal end to the distal end, may vary depending on the needle choice. In certain embodiments the needle has a length that is at least 1cm longer than the length of the guide body, preferably at least 1.5cm longer than the length of the guide body, more preferably at least 2cm longer than the length of the guide body. In this way, the distal tip of the needle is extendable beyond the distal end of the guide body such that the guide body may be positioned with the proximal end of the needle extending from the guide body while the distal end of the needle is within the passageway. The distal tip of the needle may then be extended beyond the distal end of the guide body and into patient tissue.

[0060] In certain embodiments, the device may comprise a mechanical actuator for advancing the needle in the groove or other guide passageway. The actuator can include an actuator arm that extends to the proximal end of the needle. In some forms, the mechanical actuator comprises a needle engagement member configured to grasp a portion of the needle, preferably a proximal portion (e.g. the needle hub). In some forms, the needle engagement member comprises a surface configured to push against the proximal end of the needle. The needle engagement member may also be configured to grasp a portion of the needle, preferably the proximal end of the needle (e.g. needle hub). In accordance with some forms, the needle engagement member comprises a partial loop having an opening so as to allow the release of the needle when the guide body is withdrawn from the needle.

[0061] The open portion of the needle engagement member is preferably circumferentially aligned with the passageway such that the guide body and engagement member can be removed from the needle in the same direction. In certain embodiments, the mechanical actuator comprises an actuation trigger configured to be depressed by a user's finger. In other embodiments, the mechanical actuator may be configured for remote actuation. In this way, precise control of the advancement of the needle can be controlled, either in single handed operation or remotely. In some forms, the device comprises a compression spring which is compressible upon actuation of the mechanical actuator thus biasing return of the actuator to its un-actuated position. In alternative embodiments, the device may comprise a semi-automatic actuation mechanism. In such embodiments, a compression spring is compressed in the retracted state, such that a lever or other actuation mechanism may be triggered to release the energy stored in the spring and thereby advance the distal tip of needle beyond the distal end of the device and into patient tissue.

[0062] With reference now to Figures la-ld, shown is one embodiment of a guide device

[0063] 100 as disclosed herein. Device 100 comprises guide body 102 having side wall 104 extending from proximal end 106 to distal end 108. In the illustrated embodiment, groove 110 extends from proximal end 106 to distal end 108. Groove 110 is defined by groove walls

[0064] 112 and open portion 114. Device 100 further comprises tapered distal end 130 and capping member 140. Internal chamber 150 is defined by side walls 104. Guide body 102 has a maximum width 160. Figure lb is a cutaway view, showing internal chamber 150. With particular reference to Figure 1c, shown is needle 200 having needle shaft 202 positioned in groove 110. Needle 200 extends from proximal needle end 206 to distal needle end 208.

[0065] Needle hub 204 is positioned at proximal needle end 206. In the illustrated embodiment, guide body 102 has a length 210 between proximal end 106 and distal end 108. Needle 200 extends the length 210 of guide body 102, as well as needle portion 212 extending from proximal end 106. As discussed above, such additional length allows the distal tip of the needle to be extended past distal end 108 and into patient tissue. Figure 3 is a cross- sectional view of device 100 taken along line 300, of Figure la. Chamber 150 is defined by side wall 104. Groove 110 includes groove wall 112 having a tapered wall portion 116 and a parallel wall portion 124. Groove depth 160 extends from an outer surface of the guide body immediately adjacent the groove 110 to a perpendicular line intersecting the groove bottom wall 126. Device 100 further comprises curved outer wall portion 122 and flat outer wall portion 120.

[0066] Figures 2a and 2b illustrate an embodiment of a device for MRI guided placement of a needle as disclosed herein. Device 100' comprises guide body 102' having side wall 104' extending from proximal end 106' to distal end 108'. In the illustrated embodiment, groove 110' extends from proximal end 106' to distal end 108'. Groove 110' is defined by groove walls 112' and open portion 114'. Device 100' further comprises tapered distal end 130' and capping member 140' . Needle 200' comprises needle shaft 202' positioned in groove 110'. Needle 200' extends from proximal needle end 206' to distal needle end 208'. Needle hub 204' is positioned at proximal needle end 206'. in the illustrated embodiment, guide body 102' has a length 210' between proximal end 106' and distal end 108'. Needle 200' extends the length 210' of guide body 102', as well as needle portion 212' extending from proximal end 106'. As discussed above, such additional length allows the needle to be extended past distal end 108' and into patient tissue. The illustrated embodiments further comprise a contact portion 400, comprising tapered wall portions 402, 404, and contact surface 406. In the illustrated embodiment, the depth of groove 110' within contact portion 400 is less than the depth of groove 110' outside of contact portion 400. Contact portion 400 has a length 408 configured to allow a thumb or other finger of a user to secure the exposed needle. In certain embodiment the length of the contact portion is about 20 mm to about 50 mm, preferably about 25 mm to about 40 mm.

[0067] Figures 4a and 4b illustrate another embodiment of a device for MRI guided placement of a needle as described herein. Device 100" comprises guide body 102" having side wall 104” extending from proximal end 106" to distal end 108". In the illustrated embodiment, groove 110" extends from proximal end 106” to distal end 108”. Device 100" further comprises tapered distal end 130" and capping member 140". Needle 200" comprises needle shaft 202" positioned in groove 110". Needle 200" extends from proximal needle end 206" to distal needle end 208". Needle hub 204” is positioned at proximal needle end 206”. In the illustrated embodiment, mechanical actuator 500 is mounted to guide body 102” and is movable with needle 200". Actuator 500 comprises actuator arm

[0068] 504 extending between trigger 502 and needle engagement member 506. Spring 508 is positioned between actuator arm 500 and guide body 102" such that movement of actuation arm 500 in a distal direction, for example by depressing trigger 502, will compress spring 508. In this way, spring 508 will bias the return of the actuator to its original, unactuated position after insertion of the needle into patient tissue. In some forms, the engagement member 506 is configured to grasp the proximal needle end 206”, for example the needle hub, but release the needle end 206” when the device 100" is removed from the needle 200". The engagement member 506 may partially circumferentially surround the proximal needle end 206", and have an opening 510 circumferentially aligned with the groove 110" or other passageway of the guide body and through which the needle end 206” may pass (as illustrated), for these purposes. In other forms, the engagement member 506 may include a distally-facing surface that presses upon but does not capture or grip the proximal needle end 206", so that the needle will be left in its advanced position in patient tissue even if the device 100" remains engaged with the needle 200" during return of the actuator 500 to its original, un-actuated position. These and other variations will be apparent from the descriptions herein.

[0069] Devices of the present disclosure may be advantageously configured to allow removal of the guide body from the needle in a direction transverse (e.g. perpendicular) to the guide axis defined by the guide body. In accordance with some forms, the length of the passageway includes an open side allowing for placement of a needle within the passageway and removal of the needle from the passageway in such a direction. Such a configuration is advantageous as it allows the device to be easily removed from the needle once the needle is partially inserted into patient tissue. In some other forms, the guide body can include a plurality of (i.e. two or more) guide body portions that can be selectively arranged relative to one another to constitute or deconstitute the passageway (see e.g. embodiments discussed below), such that the passageway can be deconstituted after the needle is partially inserted into patient tissue to allow the device to be easily removed from the needle. In these ways the device can be removed so as not to obstruct further insertion of the needle into patient tissue.

[0070] In preferred aspects, the present disclosure also provides for methods of MRI assisted placement of a needle into patient tissue. Such methods may comprise the step of visualizing through MRI a device as disclosed herein. In certain embodiments a method comprises aligning the guide axis defined by the device along a target path, the target path being pre-selected to intersect with a target region of patient tissue. In accordance with some forms, the target path comprises the intersection of two imaging planes. As discussed above, in accordance with some forms such methods may comprise aligning the guide axis defined by the guide body with the target path in a first plane, and while maintaining such alignment, aligning the guide axis defined by the guide body in a second plane. When a needle or other device is present in the passageway, the present disclosure provides a method for MRI visualization of the needle or other device outside of the body (i.e. prior to insertion into the body). The method may also comprise inserting the needle at least partially into patient tissue along the target path while being guided by the guide body along the guide axis defined by the guide body. In certain embodiments, the method comprises removing the guide body from the needle while the needle is partially inserted into patient tissue. In accordance with some methods, the needle is further inserted to the target region after the guide body is removed from the needle.

[0071] Particularly advantageous devices of the present disclosure may be operated by a single hand or by two hands of a user(s). Thus, in some forms, the guide devices herein may be configured to be hand held, for instance optionally having a longitudinal length of about

[0072] 25 cm or less, or about 15 cm or less. It should also be understood that devices of the present disclosure may be useful with robotic assisted procedures, for example wherein a robotic arm is used to position and use the guide device as described herein, wherein the guide device may optionally be a component of the robotic arm or may be a separate component held by the robotic arm and releasable therefrom.

[0073] In one illustrative mode of use, the guide device 100, 100' 100" can be positioned adjacent the patient and moved to a position within transverse and sagittal planes being imaged in real time or near-real time (e.g. with up to 5 seconds between refreshing images) by MRI and visually displayed. The MRI images of the transverse and sagittal planes can be visually displayed by the MRI apparatus, e.g. on a display monitor, with both showing a cross-section of the MRI visible material of the guide device 100, 100', 100" external of the patient, as well as the target path through patient tissue to the target tissue region (e.g. a target path created at the intersection of the transverse plane and the sagittal plane being imaged by the MRI apparatus). The guide device 100, 100', 100" can then be moved superiorly, inferiorly, anteriorly, posteriorly, medially, and / or laterally until the distal end of the device 100, 100', 100" is aligned with a target entry location at the intersection of the displayed target path and the skin of the patient. This alignment can for example be visualized in the displayed sagittal plane image with reference to the distal end of the device

[0074] 100, 100', 100" aligned with the target entry location. A change in the cross-sectional shape of the MRI visible material toward the distal end of device 100, 100', 100" (e.g. a taper) as imaged in the sagittal plane can provide a visual cue to assist in achieving this alignment. Additionally or alternatively, the distal end of the device 100, 100', 100" can be pressed against the skin of the patient to create an indentation thereof, which can be visualized at the target entry location, e.g. in the sagittal and / or transverse plane image. In some forms, the distal end of the guide device 100, 100', 100" can be maintained in contact with the skin of the patient during the above-mentioned movements. Once this alignment as imaged and viewed is achieved, with the distal end of the device 100, 100', 100" remaining against the skin of the patient at the target entry location, the device 100, 100' , 100" can be moved (e.g. rotated) until the marked guide path of the device 100, l00', 100" is visible and aligned with the displayed target path in the sagittal plane image. A visual check can also be made in the transverse plane image, to confirm that the guide path of the device is axially aligned with the target path shown in the transverse image. Visual confirmation of alignment of the guide path with the target path may for example occur as a directional alignment of an elongate imaged volume of the MRI visible material of the device 100, 100', 100" with the target path and / or by visualization of the marked guide path of device 100, 100', 100", depending sometimes upon the shape of the volume of MRI material incorporated into the device 100, 100', 100" and / or the rotational orientation of the device 100, 100', 100" around its longitudinal axis. The guide path of the device 100, 100', 100" will thereby be aligned in three dimensions with the target path through patient tissue. If the guide device 100, 100', 100" already has a needle received in its guide passage, the needle can be advanced distally to insert the distal tip of the needle a distance into the patient tissue along the target path. Otherwise, a needle can be inserted into the guide passageway while maintaining the position of the device 100, 100', 100" and then advanced distally to insert the distal tip of the needle a distance into the patient tissue along the target path. In some use modes, the device 100, 100', 100" can then be removed from the needle and thereafter the needle advanced further into patient tissue until the distal tip of the needle is in the target tissue region, in other forms, the needle may be sufficiently long relative to the device 100, 100', 100" that the device 100, 100', 100" may remain engaged with the needle as the distal tip of the needle is advanced to the target tissue region and potentially during all or part of a biopsy or other procedure performed in the target tissue region. Movements of the guide device 100, 100', 100" as described herein may be made manually by hand, robotically, or a combination thereof. These and other modes of use of the device 100, 100', 100" will be apparent to skilled persons from the descriptions herein. In accordance with some forms, the present disclosure provides for guide devices that include a guide body having plurality of guide body portions that are selectively arrangeable relative to one another to constitute or deconstitute the passageway for the needle or other tissue penetrating instrument. The arrangeability of the guide body portions relative to one another can be controlled by any suitable mechanism therefor, including for example cooperating shapes or guide surfaces of the guide body portions that slide against one another to control movement to and from an arrangement constituting the passageway, for example one or more slidable tongue-in-groove structures, a combination of pins and apertures for receiving the pins on the guide body portions, or a hinged connection between the guide body portions. The guide body portions of such devices may be configured to move from an open position for receiving or removing a needle or other elongate device, to a closed position wherein opposing surfaces of the guide body portions of the device are brought together to constitute the passageway, preferably in the form of a closed lumen. Devices in which first and second guide body portions are movably (e.g. hingedly or slidably) connected to one another and positionable between the closed position and the open position are preferred. The passageway, when constituted, is sized to accommodate a needle or other tissue penetrating device as described herein, and in some forms captures the needle or other tissue penetrating device against laterally- directed removal thereof from the passageway. Guide bodies, or guide body portions, as disclosed herein, may be formed from a rigid polymeric material in certain aspects, for example a polycarbonate material.

[0075] In certain embodiments, such needles or other tissue penetrating devices can include a stabilizing member friction fitted around but forcibly slidable relative to a shaft thereof, and the guide body portions, when in a position constituting the passageway, can also form a cavity for receiving the stabilizing member and preferably fixing the position of the member relative to the guide body. Devices of the present disclosure may be configured to utilize such stabilizing members to prevent gravity-imparted axial movement of the needle or other tissue penetrating instrument through the passageway and optionally center the needle within the passageway. This can be particularly beneficial in embodiments in which the passageway is not itself configured to frictionally engage the shaft of the needle / instrument so as to prevent gravity-imparted axial movement of the needle / instrument relative to the passageway, although it will be understood that in other forms the passageway can be so configured. The prevention of such gravity-imparted axial movement is beneficial because it can allow a user to grip and manipulate the guide body, while not gripping the needle / instrument, and yet maintain the axial position of the needle / instrument within the passageway. The user can then apply force to the needle / instrument, e.g. to its proximal end, to cause axial movement of the needle / instrument through the passageway, for example to insert the needle into tissue of a patient. The stabilizing member may further allow for the device to function with various shaft diameters of the tissue penetrating device, without requiring further modification of the internal diameter of the device passageway. In preferred forms, the passageway and the cavity for receiving the stabilizing member are be formed by first and second guide body portions.

[0076] In some aspects herein, at least one of, or each of, the guide body portions may comprise an MRI visible material as disclosed herein. In some forms, at least one of, or each of, the guide body portions comprise an internal chamber in which an MRI visible material, as detailed above, is contained. In certain embodiments, at least one of, or each of, the guide body portions may comprise a capping member, preferably at the proximal end, configured to seal the internal chamber(s). When multiple capping members are present each on a respective guide body portion, such capping members are preferably configured to form a proximal portion of the constituted passageway. For example, in some such forms each of the capping members comprises a groove aligned with a groove on a side wall bounding the internal chamber, such that when the guide body portions are arranged (e.g. brought together) to constitute the passageway, the passageway includes a proximal portion bounded by the grooves of the caps. In accordance with some forms, the guide device is configured to open along the longitudinal axis of the guide device by pivoting a first guide body portion and a second guide body portion relative to one another about a hinge.

[0077] In certain embodiments the first and second guide body portions of a guide body, for example a hinged guide body, may be configured with a lock mechanism to releasably secure the guide body portions together when the device is in the closed position constituting the passageway. The lock mechanism is preferably releasable such that once the device is locked in the closed position, the lock mechanism can be released to allow return of the device to the open position. The lock mechanism, in some forms, can be a detent lock mechanism by which the first and second guide body portions are held in a locked position relative to one another such that the locked position can be released by force applied to at least one of, or both of, the guide body portions. In an exemplary embodiment, a first guide body portion can include at least a first member configured for forcible flexure (e.g. having a flexible arm and a lateral projection therefrom) that is forcibly securable into and removable from a locked position relative to a second member of a second guide body portion (e.g. a cavity for receiving the lateral projection). While a holding mechanism in the form of a lock mechanism as discussed above is preferred, other holding mechanisms for holding the guide body portions in a position constituting the passageway, for example a spring bias to such position, may be used in other forms, as an alternative or in addition to a locking mechanism. in accordance with additional aspects, the device may comprise one or more gripping tabs positioned to facilitate gripping of the device and in some forms opening / closing of the device. For example, when positioned on opposing sides of a hinge, first and second gripping tabs may be forced towards one another to move the device from the closed to the open position, and in doing so optionally applying force needed to overcome a holding mechanism holding the guide body portions in position to constitute the passageway, for example to eliminate a locked condition of the lock mechanism. Similarly, such gripping tabs may be pushed apart to facilitate moving the device from the open to the closed position. Any of the embodiments disclosure herein may include one or more gripping surfaces positioned on the gripping tabs. In some forms the gripping surfaces are textured, for example having a convoluted surface, to provide increased grip. Preferably, the gripping surface comprises a material configured to enhance handling of the device by a user. For example, in some forms the gripping surface may comprise a thermoplastic elastomer or polymer such as polyurethane or a polyvinyl chloride material. The gripping surface may be provided by the same or a different material than that of the remainder of a guide body or guide body portion upon which it occurs.

[0078] Reference will now be made to the embodiments illustrated at figures 7 A, 7B, 8A, and 8B. Figure 7A shows one embodiment of a hinged guide device 700 in an open position.

[0079] Figure 7B shows one embodiment of a hinged guide device 700 in a closed position. Figure

[0080] 8A is a top-down view of the hinged guide device of figure 7A. Figure 8B is a top-down view of the hinged guide device of figure 7B, without capping members 718, 728. Hinged guide device 700 comprises a first guide body portion 702 and a second guide body portion 704 joined by a hinge 706. First guide body portion 702 comprises first sidewall 710 and first groove 712 extending longitudinally along the length of first sidewall 710 from proximal end

[0081] 714 to distal end 716. Second guide body portion 704 comprises second sidewall 720 and second groove 722 extending longitudinally along the length of second sidewall 720 from proximal end 724 to distal end 726. Guide device 700 comprises a tapered distal end 730 comprising tapered distal end portion 732 of first guide body portion 702 and tapered distal end portion 734 of second guide body portion 704. When in the closed configuration constituting the passageway (Figures 7B and 8B) the first side wall 710 and second side wall 720 are brought together to form passageway 740 in the form of a lumen defined by the walls of first groove 712 and second groove 722. Passageway 740 extends the length of guide device 700. Locking arm 750 may be positioned on either of the guide body portions.

[0082] In the illustrated embodiment locking arm 750 is positioned near the proximal end of first guide body portion 702. Receiving area 752 is configured to receive and engage a projection of the locking arm 750 in a detent locking arrangement to secure the device in the closed position. In accordance with some forms, receiving area 752 may comprise a ridge of other structure suitable to engage a surface of locking arm 750. Devices of the present disclosure may include one or more capping members. Devices of the present disclosure may also comprise a first gripping tab 760 and a second gripping tab 762. With reference to figure 8B specifically, with capping members 718, 728 removed, first internal chamber 1300 defined by first internal chamber wall 1308, and second internal chamber 1310 defined by second internal chamber wall 1318, are visible.

[0083] Figure 9 is a side view of one embodiment of first guide body portion 702 having first groove 712 on first side wall 710 extending from proximal end 714 to distal end 716. A first cavity portion 772 for forming a cavity to receive a stabilizing member is positioned near the distal end 716. Figure 10 is a side view of one embodiment of second guide body portion

[0084] 704 having second groove 722 on second side wall 720 extending from proximal end 724 to distal end 726. A second cavity portion 774 for forming the cavity to receive the stabilizing member is positioned near the distal end 726. In the illustrated embodiment, the hinge 706 includes a pin 900 captured at each end in receivers 707 defined by the first guide body portion 702. The first guide body portion 702 also defines an interleaving member 902 having a concave surface that partly encircles and travels against the surface of the pin 900. The second guide body portion 704 has a first pair of opposed arcuate walls 1002 and 1004 that together define a first open-sided knuckiel006, and a second pair of opposed arcuate walls 1012 and 1014 that together define a second open-sided knuckle 1016. These open sided knuckles 1006 and 1016 are configured to snap fit around pin 900 through their side openings to hingedly connect the first guide body portion 702 and the second guide body portion 704 at the hinge 706. In this connection, the interleaving member 902 is positioned longitudinally between the knuckles 1006 and 1016. As the guide body portions 702 and 704 are pivoted relative to one another while moving between the open position and the closed position, the knuckles 1006 and 1016 rotate around the pin 900. It will be understood that the specific hinge 706 is an illustrative embodiment, and that the use of other hinge arrangements, including for example a living hinge made from the same material incorporated in the guide body portions 702 and 704, is contemplated within the scope of the present disclosure. in beneficial forms, the guide body portions 702 and 704 will be hingedly connected and will be configured to limit the range of pivotal motion between them as they move between the open and closed positions. For example, moving toward the closed position, the pivotal motion can be stopped when the faces 710 and 720 of the respective guide body portions contact one another. Moving toward the open position, the pivotal motion can be stopped by a stop surface on the first guide body portion 702 contacting a stop surface on the second guide body portion 704. In the illustrated form, the first guide body portion 702 defines a stop arm 802 having a stop surface 804 that contacts a wall surface

[0085] 806 on the second guide body portion 704 to stop the pivotal motion. In certain preferred forms, the pivotal motion of the guide body portions 702 and 704 relative to one another can be limited to less than about 90 degrees, for example in the range of about 10 degrees to about 90 degrees, or in the range of about 20 degrees to about 60 degrees. In addition, or alternatively, the pivotal motion of the guide body portions 702 and 704 toward the open position will be stopped to leave the outer gripping surfaces 812 and 814 of the gripping tabs 762 and 760 spaced from one another a distance of at least about 20mm to about 50mm or at least about 25mm to about 40mm. This limited range of pivotal motion and / or spacing can facilitate a user maintaining a firm and steady grip (e.g. with a thumb and finger) on the gripping surfaces 812 and 814 and thereby on the guide device 700, during and after squeezing the gripping tabs 762 and 760 toward one another to open the device 700. The gripping surfaces 812 and 814 can be ribbed, for example as shown, or can have another convoluted surface to enhance gripping of the guide device by such gripping surfaces.

[0086] Figures 11A and 118 show one embodiment of a stabilizing member for use with the presently disclosed device 700. in particular, Figure 11A is a perspective view of a stabilizing member. Figure 118 is a top-down view of the stabilizing member of Figure 11A. In the illustrated embodiment, stabilizing member 1100 has a generally cylindrical body 1101 that defines a stabilizing member lumen 1102 extending from proximal end 1106 to distal end 1108. Lumen 1102 is sized to frictionally but slidably engage the shaft of a needle or other tissue penetrating instrument so as to prevent gravity-imparted movement of the shaft through the lumen 1102 but otherwise allow forcible movement of the shaft through the lumen 1102. In accordance with some forms, the generally cylindrical body 1101 comprises a plurality of longitudinal portions having varying widths. In the illustrated embodiment, proximal longitudinal portion 1110 has a greater width than distal longitudinal portion 1112. The stabilizing member 1100 or other stabilizing members herein can be provided by so-called needle depth stops, which are commonly available in conjunction with commercial needles. Thus, the guide device 700 can be used in with both commercial needles and depth stops (used as the stabilizing member herein) typically packaged along with such needles. In other forms, a stabilizing member may be provided separately from a needle or other tissue penetrating instrument, for example packaged with guide device 700 in a kit, or individually packaged.

[0087] Figure 12 is a partial view of the distal end of guide body portion 702. In the illustrated embodiment, a portion of stabilizing member 1100 is positioned within cavity portion 772 such that the stabilizing member lumen 1102 is in line with first groove 712. In this way, when the guide device 700 is closed, the stabilizing member 1100 is held within the cavity 770 formed by the first and second cavity portions 772 and 774. The stabilizing member lumen 1102 is positioned in line with the passageway 740.

[0088] Figure 13 is a cross sectional view of the guide device 700 in the dosed position. A first internal chamber 1300 is defined by internal wall 1302 of first guide body portion 702 and open end 1304. Open end 1304 is sealed by first capping member 718. In the illustrated embodiment, a distal portion 1306 of internal chamber 1300 is tapered. In some forms such tapered distal portion corresponds to the tapered portion 732 of guide body portion 702. A second internal chamber 1310 is defined by internal wall 1312 of second guide body portion 704 and open end 1314. Open end 1314 is sealed by second capping member 728. In the illustrated embodiment, a distal portion 1316 of internal chamber 1310 is tapered. In some forms, such tapered distal portion corresponds to the tapered portion 734 of guide body portion 704. As discussed for other embodiments herein, the internal chamber 1300 and the internal chamber 1310 can contain an MRI visible material, such as any of those disclosed above. In such forms, the guide device 700 can be used in an MRI guided medical procedure in the same fashion as the guide devices 100, 100' and 100" disdosed above.

[0089] Stabilizing member cavity 770 is formed by the first and second cavity portions 772 and 774.

[0090] In some forms in which guide device 700 is used in conjunction with a stabilizing member, after opening the device 700 and separating it from the needle or other tissue penetrating instrument, the stabilizing member will remain on the tissue penetrating instrument. Where the needle / instrument has already been inserted into patient tissue and there is a desire to further insert it, if needed, the stabilizing member can be manually slid proximally along the shaft of the needle / instrument to provide a length of the shaft distal of the stabilizing member that is suitable for the further insertion.

[0091] Figure 14 is a rear-view of one embodiment of a hinged guide device 700' in an open position. Figure 15 is a top-down view of the hinged guide device of Figure 14. Hinged guide device 700' comprises a first guide body portion 702' and a second guide body portion 704' joined by a hinge 706'. Figure 16A is a perspective view of first guide body portion 702'.

[0092] Figure 168 is a bottom-up view of first guide portion 702'. Figure 17A is a perspective view of second guide body portion 704'. Figure 17B is a bottom-up view of second guide body portion 704'. First guide body portion 702' comprises first sidewall 710' and first groove 712' extending longitudinally along the length of first sidewall 710' from proximal end 714' to distal end 716'. Second guide body portion 704' comprises second sidewall 720' and second groove 722' extending longitudinally along the length of second sidewall 720' from proximal end 724' to distal end 726'. Guide device 700' comprises a tapered distal end 730' comprising tapered distal end portion 732' of first guide body portion 702' and tapered distal end portion 734' of second guide body portion 704'. When in the closed configuration constituting the passageway the first side wall 710' and second side wall 720' are brought together to form a passageway, preferably in the form of a lumen, defined by the walls of first groove 712' and second groove 722'. The passageway extends the length of guide device 700'. Locking arm 750' may be positioned on either of the guide body portions. In the illustrated embodiment locking arm 750' is positioned near the proximal end of first guide body portion 702'. Receiving area 752' is configured to receive and engage a projection of the locking arm 750' in a detent locking arrangement to secure the device in the closed position. In accordance with some forms, receiving area 752' may comprise a ridge of other structure suitable to engage a surface of locking arm 750'. Devices of the present disclosure may include one or more capping members as described above. In the embodiments illustrated at Figures 16A and 17A, first capping member 718' is positioned at the proximal end of first guide body portion 702', and second capping member 728' is positioned at the proximal end of the second guide body portion 704'. Devices of the present disclosure may also comprise a first gripping tab 760' and a second gripping tab 762'. In the illustrated embodiment, first internal chamber 1300' defined by first internal chamber wall 1308', and second internal chamber 1310' is defined by second internal chamber wall 1318'. The gripping tabs 760' and 762', and other gripping tabs disclosed herein, may have a convoluted gripping surface, for example ridged gripping surface having a plurality of ridges or a knurled surface. Such convoluted surfaces can provide an enhanced frictional grip (e.g. with a thumb and / or finger) of the gripping tabs as compared to a corresponding smooth surface. In some forms, a layer 820' of a second material can be attached (e.g. bonded) to an underlying first material of the gripping tab 760' and / or 762' or other gripping tabs herein, optionally wherein the second material provides a convoluted gripping surface as discussed above. The second material can be a polymeric material that is softer and / or provides a surface having a higher coefficient of friction than the first (e.g. polymeric) material.

[0093] In accordance with some forms, first guide portion 702' and second guide portion

[0094] 704' are configured to receive a pin 1800 to join the guide portions together. In certain embodiments one or more barrels is positioned on each of the first and second guide portions and configured to receive a pin. In the illustrated embodiments, barrel 1600 is positioned on first guide body portion 702'. Barrel 1600 defines a portion of barrel lumen 1602 sized to receive pin 1800. Barrels 1700 and 1702 are positioned on second guide body portion 704'. Barrels 1700 and 1702 define further portions of barrel lumen 1602. While the illustrated embodiment is shown with one barrel positioned on the first guide body portion and two barrels positioned on the second guide body portion, it is within the scope of the disclosure to provide any suitable number of barrels on either of the guide body portions. In beneficial forms, the guide body portions 702' and 704' will be hingedly connected and will be configured to limit the range of pivotal motion between them as they move between the open and closed positions. For example, moving toward the closed position, the pivotal motion can be stopped when the faces 710' and 720' of the respective guide body portions contact one another. Moving toward the open position, the pivotal motion can be stopped by a stop surface on the first guide body portion 702' contacting a stop surface on the second guide body portion 704'. In the illustrated embodiment, stop arms

[0095] 802' are positioned on barrels 1700 and 1702. Each stop arm 802' comprises a stop surface 804' that contacts a wall surface 806' on the first guide body portion 702' to limit the pivotal motion. These and other structures that can limit pivotal motion, for example limit hinge structures, can be used in embodiments herein. In certain preferred forms, the pivotal motion of the guide body portions 702' and 704' relative to one another can be limited to less than about 90 degrees, for example in the range of about 10 degrees to about 90 degrees, or in the range of about 20 degrees to about 60 degrees. In addition, or alternatively, the pivotal motion of the guide body portions 702' and 704' toward the open position will be stopped to leave the outer gripping surfaces 812' and 814' of the gripping tabs 762' and 760' spaced from one another a distance of at least about 20mm to about 50mm or at least about 25mm to about 40mm. This limited range of pivotal motion and / or spacing can facilitate a user maintaining a firm and steady grip (e.g. with a thumb and finger) on the gripping surfaces 812' and 814' and thereby on the guide device 700', during and after squeezing the gripping tabs 762' and 760' toward one another to open the device 700'.

[0096] Figure 18A is a perspective view of one embodiment of a pin 1800. Figure 18B is a bottom-up view of the pin of figure 18A. In the illustrated embodiment, pin 1800 comprises an elongate shaft 1802 and a head 1804 having a larger diameter than that of shaft 1802. In this way, shaft 1802 may be inserted through the barrel lumen up to head 1804 which has a larger diameter than the barrel lumen. In some forms, pin 1800 comprises flat surface 1806 configured to contact a portion of first and second guide portions 702' and 704'. In accordance with some forms, the guide body may include one or more protrusions configured to prevent removal of pin 1800 from barrel lumen 1602. In the illustrated embodiment, ledge 1402 is positioned on first guide body portion 702' proximal to head 1804 such that if pin 1800 is moved in a proximal direction contact with ledge 1402 prevents removal of pin 1800. In the illustrated embodiment, ledge 1412 is positioned on second guide body portion 704' proximal to head 1804 such that if pin 1800 is moved in a proximal direction contact with ledge 1412 prevents removal of pin 1800.

[0097] In accordance with some forms, each of the guide body portions may be constructed from one or more pieces, for example from one or more molded pieces. In one example a guide body portion, similar to those shown in Figures 16A and 17 A may be assembled from two molded pieces. In one example, a first piece of first guide body portion 702' comprises the piece of first guide body portion 702' extending distal to line X, and a second piece of first guide body portion 702' comprises the piece of first guide portion 702' extending proximal to line X. Additionally or alternatively, a first piece of second guide body portion

[0098] 704' comprises the piece of second guide body portion 704' extending distal to line Y, and a second piece of second guide body portion 704' comprises the piece of second guide portion 704' extending proximal to line X. In this way the present disclosure provides for methods of making or assembling a device as disclosed herein comprising attaching a first piece of a guide body portion, for example the first and / or second guide body portion, to a second piece of a guide body portion to form a complete guide body portion. Such attaching is preferably fluid sealed, and may be accomplished by any suitable means for example, gluing, welding, melting, or mechanical interlocking. In one example, ledge 1402 is positioned on the first piece of first guide body portion 702' and ledge 1412 is positioned on the first piece of second guide body portion 704'. Assembly of a device, for example a device as shown in Figure 14 may comprise the step of attaching a first piece of a first guide body portion to a first piece of a second guide body portion. Such attaching may comprise aligning barrels positioned on each of the first piece of a first guide body portion and the first piece of a second guide body portion to form a barrel lumen and inserting a pin through the barrel lumen. As detailed above the pin may include an enlarged head portion. Such methods may further comprise attaching a second piece of the first guide body portion to the first piece of the first guide body portion, and / or attaching a second piece of the second guide body portion to the first piece of the second guide body portion. In this way, the ledge portion of the second piece of the first and / or second guide body portions is positioned after the pin is inserted into the barrel lumen. Once positioned the ledge portion(s) obstructs removal of the pin from the barrel lumen. In accordance with some forms, the present disclosure provides for methods for preparing a device for guided placement of a tissue penetrating instrument. Such methods may include the step of loading a tissue penetrating instrument into the passageway of a device as disclosed herein. In embodiments in which the guide body is movable from an open to a closed position, the tissue penetrating instrument is preferably loaded into the device with the guide body in the open position. In this way, in advantageous embodiments, the instrument can be moved laterally (transverse to the passageway to be constituted) between the plurality of guide body portions with the guide body in the open position and then the guide body moved to the closed position to constitute the passageway around the instrument. In some forms, a stabilizing member may be positioned on the tissue penetrating instrument prior to loading of the instrument into the guide body. In this way, movement of the guide body from the open to the closed position, as disclosed above, can also capture the stabilizing member in a cavity formed by the guide body in the closed position.

[0099] Any or all of the components described herein can be provided within sterile packaging for providing a medical product, or a variety of medical products, to a user. For example, one or more guide bodies may be provided in a single sterile package or kit. A physician can choose the sizes or types of guide body he or she wishes to use during an MRI procedure, for example to accommodate a specific needle or other implement.

[0100] Alternatively, sterile kits containing predetermined needles and guide bodies may also be provided. Additionally, or alternatively such kits may include an MRI visible material to be added to the guide body, for example within the chamber(s) designed therefor as discussed above. Packages or kits of the components described herein can include additional devices or tools which may be useful in the particular medical procedure being performed.

[0101] The following specific example is provided to promote a further understanding of certain aspects of the present disclosure. It will be understood that this example is illustrative, and not limiting in character.

[0102] Example 1

[0103] A device for MRI guided placement of a needle as shown in Figures la-ld was used to position and orient a 20-gauge FNA needle using a biplanar set of magnetic resonance images. In this experiment a biplanar MRI was used to display a transverse plane (TRA) and a sagittal plane (SAG). Figure 5A shows the device positioned over the target path in the transverse plane. As shown in Figure SB, the device was then positioned with the distal tip over the target path in the sagittal plane, while maintaining position in the transverse plane.

[0104] As also shown in Figure 5B, a depression in the tissue was created by the distal tip of the device as it was positioned over the guidance path created at the intersection of two imaging planes. The device was adjusted over the entry point of the guidance path until its center-most cross section (e.g. the passageway) is visible in each imaging plane and the needle was inserted along the axis of insertion at least two centimeters into the tissue (Figure 5C). With the needle partially inserted into the tissue, Figure 5D shows the MRI guided placement device removed from the imaging planes and needle advanced along the guidance path until a targeted region of the tissue is reached.

[0105] It is intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention. All publications and patent applications cited in this specification are herein incorporated by reference as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Further, any theory, mechanism of operation, proof, or finding stated herein is meant to further enhance understanding of the present invention, and is not intended to limit the present invention in any way to such theory, mechanism of operation, proof, or finding. While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only selected embodiments have been shown and described and that all equivalents, changes, and modifications that come within the spirit of the inventions as defined herein or by the following claims are desired to be protected.

Claims

CLAIMSWhat is claimed is:

1. A device for magnetic resonance imaging (MRI) guided placement of a needle, the device comprising: a guide body comprising an MRI visible material and defining an elongate passageway configured to receive and guide a shaft of a tissue penetrating instrument along an axis for insertion into a patient.

2. The device of claim 1, wherein the passageway is a groove extending along a side wall of the guide body.

3. The device of claim 2, wherein the groove has a bottom wall surface for receipt against a sidewail surface of the shaft to guide the shaft.

4. The device of any one of claim 2 or 3, wherein the groove has at least a portion that narrows in a direction toward a bottom wall of the groove.

5. The device of any one of claim 2 through 4, wherein the groove comprises a bottom wall surface, and wherein the bottom wall surface is contoured to conform to a portion of a circumference of the shaft.

6. The device of claim 5, wherein the bottom wall surface is concave curve.

7. The device of claim 6, wherein a cross-section of the bottom wall surface forms an arc of a circle.

8. The device of any one of claims 1 through 7, wherein the guide body defines an internal chamber, and wherein the MRI visible material is received within the internal chamber.

9. The device of any one of claims 1 through 8, wherein the guide body comprises a flat outer wall portion, and wherein the passageway extends through the flat wall portion.

10. The device of any one of claims 1 through 9, wherein the passageway comprises a groove, and wherein the groove has a first segment having a first depth and a second segment having a second depth different from the first depth.

11. The device of claim 10, wherein the second depth is less than the first depth.

12. The device of any one of claims 10 or 11, wherein the second depth is less than a diameter of the shaft.

13. The device of any one of claims 10 to 12, wherein the groove has a third segment, with the second segment positioned between the first segment and the third segment, and wherein the third segment has a third depth greater than the second depth.

14. The device of any one of the preceding claims, wherein the passageway extends from a proximal end of the guide body to a distal end of the guide body.

15. The device of any one of the preceding claims, wherein the guide body comprises a tapered distal end.

16. The device of any one of the preceding claims, wherein a proximal end of the guide body comprises a capping member, and wherein the capping member defines a portion of the passageway.

17. The device of any one of the preceding claims, wherein the passageway extends into the guide body such that when present the shaft within the passageway is partially surrounded by MRI visible material.

18. The device of any one of the preceding claims, wherein the guide body is configured to visibly mark the axis under MRI visualization; optionally, wherein the guide body is configured to be imaged by MRI in a plane having first and second regions of MRI visiblematerial flanking the passageway and the passageway is free of or has less of the MRI visible material in said plane, such that the passageway is visually contrasted to the regions.

19. The device of any one of the preceding claims, also comprising: a actuator arranged to engage and move the instrument along the axis.

20. The device of claim 19, comprising: a spring positioned between an actuation arm of the actuator and the guide body such that movement of the actuation arm in a distal direction causes compression of the spring.

21. The device of any one of claims 19 or 20, wherein the actuator comprises an instrument engagement member configured to grip the proximal instrument end, the engagement member having an open portion so as to allow release of the proximal instrument end.

22. The device of any one of claims 1 to 21, wherein the tissue penetrating instrument is a needle and / or wherein the guide body includes a plurality of guide body portions that are reversibly arrangeable relative to one another to constitute the elongate passageway in a closed position or deconstitute the elongate passageway in an open position.

23. A combination, comprising the device of any one of the preceding claims and a tissue penetrating instrument having a shaft receivable in the passageway.

24. The combination of claim 23, wherein the shaft has a shaft length which is at least 2 centimeters longer than a length of the passageway.

25. A method of magnetic resonance imaging (MRI) guidance, comprising: positioning a guide body comprising an MRI visible material, the guide body defining an elongate passageway configured to receive and guide a shaft of a tissue penetrating instrument along an axis for insertion into a patient, said positioning comprising aligning the axis with a target path through patient tissue; anddisplaying an MRI generated image including the target path and the guide body.

26. The method of claim 25, wherein during the positioning the shaft of the tissue penetrating instrument is received in the passageway.

27. The method of claim 25, also comprising: inserting the tissue penetrating instrument at least partially into patient tissue along the target path.

28. The method of claim 27, comprising: removing the guide body from the instrument while the instrument is at least partially inserted into patient tissue.

29. The method of claim 28, comprising: advancing the instrument to a target region along the target path after said removing of the guide body.

30. The method of any one of claims 25 through 29, wherein: said displaying comprises utilizing biplanar MRI to visualize the target path in a first plane and a second plane, and wherein said positioning comprises positioning the axis along the target path in each of the first plane and the second plane.

31. The method of any one of claims 25 through 30, wherein: the positioning is conducted all or in part, manually by hand.

32. The method of any one of claims 25 through 30, wherein: the positioning is conducted all or in part, robotically.

33. The method of claim 32, wherein the robotically positioning is conducted with the guide body on a robotic arm.

34. A device for guided placement of a needle, the device comprising:a guide body defining an elongate passageway configured to receive and guide a shaft of a tissue penetrating instrument along an axis for insertion into a patient, the guide body including a plurality of guide body portions that are reversibly arrangeable relative to one another to constitute the elongate passageway in a closed position or deconstitute the elongate passageway in an open position.

35. The device of claim 34, wherein: the plurality of guide body portions includes a first guide body portion defining an elongate first groove and a second guide body portion defining an elongate second groove.

36. The device of claim 35, wherein the first guide body portion is movably connected to the second guide portion, optionally wherein the first guide body portion is hingedly connected to the second guide portion.

37. The device of claim 36, wherein the first guide body portion and the second guide body portion are pivotable relative to one another from the open position to the closed position, wherein in the closed position the first groove and the second groove are brought together to constitute the elongate passageway.

38. The device of any one of claims 34 to 37, wherein: with the plurality of guide body portions arranged to constitute the elongate passageway, the guide body also defines a cavity positioned along the elongate passageway and configured to receive a stabilizing member friction fitted around and slidable relative to the shaft of the tissue penetrating member.

39. The device of any one of claims 34 to 38, wherein at least one of the plurality of guide body portions comprises an MRI visible material.

40. The device of any one of claims 34 to 38, wherein each of the plurality of guide body portions comprises an MRI visible material.

41. The device of claims 39 or 40, wherein the plurality of guide body portions includes a first guide body portion that defines a first internal chamber, and wherein an MRI visible material is received within the first internal chamber.

42. The device of claim 41, wherein the plurality of guide body portions includes a second guide body portion that defines a second internal chamber, and wherein an MRI visible material is received within the second internal chamber.

43. The device of any one of claims 34 through 42, wherein the guide body comprises a tapered distal end with the plurality of guide body portions arranged to constitute the elongate passageway.

44. The device of claim 43, wherein each of the plurality of guide body portions forms a part of the tapered distal end with the plurality of guide body portions arranged to constitute the elongate passageway.

45. The device of any one of claims 34 through 44, wherein a proximal end of each of the plurality of guide body portions comprises a respective capping member; optionally wherein the capping members are configured to together define a portion of the elongate passageway with the plurality of guide body portions arranged to constitute the elongate passageway.

46. The device of any one of claims 34 through 45, wherein the tissue penetrating instrument is a needle.

47. The device of any one of claims 34 to 46, wherein at least one of the plurality of guide body portions defines a first gripping tab.

48. The device of any one of claims 34 to 46, wherein a first of the plurality of guide body portions defines a first gripping tab and a second of the plurality of guide body portions defines a second gripping tab.

49. The device of claim 48, wherein with the plurality of guide body portions arranged to constitute the elongate passageway, the first gripping tab and second gripping tab are spaced from one another and are movable toward one another to deconstitute the elongate passageway.

50. The device of any one of claims 48 or 49, wherein each of the first gripping tab and the second gripping tab extends transversely to a longitudinal axis of the guide body.

51. The device of claim 50, wherein the first gripping tab defines a first outer gripping surface facing opposite of the second gripping tab and the second gripping tab defines a second outer gripping surface facing opposite of the first gripping tab.

52. The device of claim 51, wherein each of the first outer gripping surface and the second outer gripping surface defines a concave curve.

53. The device of claim 51 or 52, wherein each of the first outer gripping surface and the second outer gripping surface defines a convoluted surface pattern.

54. The device of claim 53, wherein the convoluted surface pattern is a ridged surface pattern.

55. The device of claim 37 or of any one of claims 38 to 54 as dependent on claim 37, wherein the first guide body portion and the second guide body portion are configured with stop surfaces that limit their pivotable motion relative to one another between the closed position and the open position.

56. The device of claim 55, wherein the pivotable motion is limited to about 90 degrees or less between the closed position and the open position.

57. The device of claim 55, wherein the pivotable motion is limited to about 60 degrees or less between the closed position and the open position.

58. A combination, comprising the device of any one of claims 34 through 57 and a tissue penetrating instrument having a shaft receivable in the elongate passageway.

59. A method of magnetic resonance imaging (MRI) guidance, comprising: positioning a device according to any one of claims 34 through 57, said positioning comprising aligning the elongate passageway with a target path through patient tissue with the plurality of guide body portions arranged to constitute the elongate passageway; and displaying an MRI generated image including the target path and the guide body.

60. The method of claim 59, wherein during the positioning a shaft of a tissue penetrating instrument is received in the elongate passageway.

61. The method of claim 60, also comprising: inserting the tissue penetrating instrument at least partially into patient tissue along the target path.

62. The method of claim 61, comprising: removing the device from the tissue penetrating instrument while the instrument is at least partially inserted into patient tissue.

63. The method of claim 62, wherein said removing comprises moving the plurality of guide body portions relative to one another to deconstitute the elongate passageway.

64. The method of any one of claims 61 to 63, comprising: advancing the instrument to a target region along the target path after said removing.

65. The method of any one of claims 59 to 64, wherein: said displaying comprises utilizing biplanar MRI to visualize the target path in a first plane and a second plane, and wherein said positioning comprises positioning the axis along the target path in each of the first plane and the second plane.

66. The method of any one of claims 59 to 65, wherein: the positioning is conducted all or in part, manually by hand.

67. The method of any one of claims 59 to 65, wherein: the positioning is conducted all or in part, robotically.

68. The method of claim 67, wherein the robotically positioning is conducted with the guide body on a robotic arm.

69. A method for preparing a device for guided placement of a tissue penetrating instrument, comprising: loading a tissue penetrating instrument into the passageway of a device of any one of claims 1-22, or 34-57.

70. The method of claim 69, wherein said loading is performed with the device in the open position.

71. The method of any one of claims 69 or 70, comprising: positioning a stabilizing member on the tissue penetrating instrument prior to said loading.

72. The method of claim 71, wherein the device comprises a device according to any one of claims 34-57, and wherein the stabilizing member is positionable within a cavity along the passageway.

73. The method of any one of claims 69 through 72, comprising: closing the guide body to constitute the elongate passageway around at least a portion of the tissue penetrating instrument and wherein said loading is performed with the device in the open position.

Images