Guide for an endoscope, particularly a colonoscope, and an endoscopy system including said guide

Abstract

The present invention relates to an endoscopy guide, particularly suitable for colonoscopy applications. The present invention is directed to an endoscopy system, particularly directed to a colonoscopy, comprising a tubular guide element (1) and an anchor head (2), the tubular guide element (1) having a longitudinal cavity (3), the anchor head (2) comprising an expandable container (4) configured to contain a ferromagnetic agent, the expandable container (4) being in communication with said longitudinal cavity (3), the endoscopy system further comprising a ferromagnetic agent configured to be movable within said longitudinal cavity for filling / emptying the expandable container (4), the ferromagnetic agent being an aqueous suspension of carbonyl iron.

Description

[Technical field]

[0001] The present invention relates to an endoscopic guide for a catheter or endoscope, and is particularly suitable for use in colonoscopy.

[0002] Examples of such instruments include colonoscopes, enteroscopes, gastroscopes, duodenoscopes, and echoscopes. [Background technology]

[0003] Endoscopic guides (or "guidewires" in technical terms) are used in particular in the field to position and act as guides for catheters. The catheters are usually slidably mounted over the guidewire. In this regard, the catheter is provided with a working channel in which the guide itself is located with its assembly.

[0004] Various types of endoscopic guides are known from the prior art depending on their intended use.

[0005] One type of endoscopic guide provides an anchor head that allows the guide to remain in place and act as a support for manipulation of the catheter and endoscope.

[0006] In this regard, in certain embodiments, the guide comprises an inflatable balloon which, when introduced and positioned within the lumen of the organ, is inflated with air until it interferes with the wall of the lumen itself, thus remaining occluded in place.

[0007] While such guides having expandable anchor heads have been used, they suffer from significant drawbacks.

[0008] Another limitation of some of these solutions is that the lumen in which the guide head is located is occluded, especially in the case of an inflatable balloon, where the occlusion is complete.

[0009] Moreover, such anchor heads are difficult to use in certain endoscopic fields, for example in the case of colonoscopy, due to the anatomical shape of the organ in which the guide is introduced. Indeed, the diameter of the lumen of the colon can vary from 2-3 cm to 6-8 cm, depending on the part to be examined and the presence or absence of pathological conditions or anatomical abnormalities. This can lead to the need for rather large balloons.

[0010] Furthermore, fixation via the balloon is obtained by friction occurring between the balloon and the surface of the organ mucosa. As a result, lesions may occur in the organ wall. In the case of colonoscopy, the blockage due to friction results in the need to stretch the balloon more and increase the pressure on the organ wall in order to obtain a more stable fixation. However, this maneuver carries the risk of leading to excessive stretching of the organ, causing pain or even tissue tearing. Furthermore, especially in elderly people or in certain pathological conditions, the organ may be distended or relaxed and may not offer resistance to the balloon expansion. In this condition, balloon expansion is not only dangerous but also ineffective.

[0011] However, to ensure reliable operation of the guides in colonoscopes and endoscopes in general, it is necessary to obtain a firm and stable fixation.

[0012] In particular, colonoscopy requires care when guiding the colonoscope to the end of the large intestine, called the cecum, because the large intestine has a tortuous path and loose walls, which can lead to the formation of loops that can impede the progress of the tip of the colonoscope or stretch the walls of the colon, resulting in pain and the risk of lacerating the organs. In these cases, the physician must either clear the path as much as possible and proceed by guiding the colonoscope to the cecum, or in any case manipulate the instrument in an appropriate manner to explore the entire organ.

[0013] It should also be noted that the main difference between a colonoscope and a standard catheter is the greater mass of the former. The increased mass of a catheter or endoscope requires a more rigid guide. However, the guides currently used in endoscopy cannot be made of particularly rigid materials, since a rigid tip could damage the internal organs.

[0014] Many of the problems associated with prior art devices have been overcome by endoscopy guides and endoscopy systems including same, such as those described in European Patent EP3399901A1 to the present applicant. Such patent describes a system for magnetically fixing the tip of an endoscopy guide by introducing a magnetic fluid consisting of an aqueous suspension of iron powder, magnetite, maghemite, or ferrofluid into an inflatable balloon. Fixation is obtained by applying a magnetic field of suitable strength from the outside. Summary of the Invention [Problem to be solved by the invention]

[0015] Although such systems allow adequate fixation to the wall of the colon without obstructing the organ lumen and without damaging the organ tissue, they suffer from various drawbacks.

[0016] The first problem is that the guide catheter is prone to so-called kinking during the introduction step along the tortuous path of the large intestine.

[0017] It was also found that by using the volumes of magnetic fluid and the concentrations of magnetizable particles contained therein provided in the prior patents, excessive viscosity of the fluid was obtained, which resulted in long times to fill and empty the balloon and excessive force required to be applied by the operator to fill it.

[0018] Additionally, the frequent formation of clusters and / or agglomerates of ferromagnetic particles within the balloon after application of the magnetic field further slows or prevents emptying at the end of operation.

[0019] Clusters and / or agglomerates of the same ferromagnetic particles can in some cases already form in pre-filled syringes during storage, thus hindering the filling of the balloon and rendering the system in place for the latter unusable.

[0020] It is therefore an object of the present invention to provide an endoscopic guide for a catheter or endoscope which overcomes one or more of the technical problems set out above with respect to known magnetic anchor systems.

[0021] In particular, it is an object of the present invention to produce an endoscopic guide that can be operated more quickly with less effort or risk of blockage compared to known endoscopic guides with magnetic anchors, and that can be easily manufactured at a relatively affordable price to be a disposable system. [Means for solving the problem]

[0022] To achieve one or more of the objectives and aims set out above, as well as other objectives identified below, This is achieved by: 1) an endoscopy system, in particular an endoscopy guide for a colonoscope, comprising a tubular guide element and an anchor head, the tubular guide element comprising a longitudinal cavity, the anchor head comprising at least one expandable container configured to house a ferromagnetic agent, the expandable container being in communication with the longitudinal cavity, the endoscopy system further comprising a ferromagnetic agent configured to be movable within the longitudinal cavity for filling / emptying the container, the ferromagnetic agent being an aqueous suspension of carbonyl iron.

[0023] Other objects of the present invention are as follows:

[0024] 2) An endoscopy system according to point 1), further comprising a magnetic field source configured to apply a holding force of 5 Newtons or more to the ferromagnetic agent in a lateral pulling direction at a distance between 2 centimeters and 10 centimeters from the ferromagnetic agent.

[0025] 3) A system according to points 1) or 2), further comprising a syringe pre-filled with said ferromagnetic agent.

[0026] 4) The carbonyl iron has a purity of 97.5% or more, or 99.5% or more; D10 = 3-4.5 microns or about 4.1 microns D50=5-10 microns or about 9.5 microns D90=4-30 microns or 26 microns The system according to any one of points 1) to 3), comprising spherical particles having a particle size profile of:

[0027] 5) The system according to any one of points 1) to 4), wherein the aqueous suspension of carbonyl iron contains 45% to 60% by weight, or 50% to 55% by weight, or 52% to 53% by weight of carbonyl iron, relative to the total weight of the suspension.

[0028] 6) The system according to any one of points 1) to 5), wherein the aqueous suspension of carbonyl iron contains 2.5% to 4.5% by weight of tribasic sodium citrate relative to the total weight of the suspension and / or 5% to 8% by weight of sodium chloride relative to the total weight of the suspension.

[0029] 7) A system according to any one of points 1) to 6), wherein the tubular guide element has a single lumen and an outer diameter of less than 2.6 mm or about 2.5 mm, and the inner diameter of the lumen of the tubular guide element is between 1.6 mm and 1.75 mm, or about 1.7 mm.

[0030] 8) A system according to any one of points 1) to 7), wherein the expandable container comprises or consists of an expandable balloon and is sized to have a volume of 22 to 28 ml or about 25 ml, a length in an expanded state of 55 to 65 mm or about 60 mm, and a transverse diameter of 20 to 30 mm or about 25 mm.

[0031] 9) A system according to any one of points 1) to 8), wherein the syringe has a cylinder into which the piston is slidably inserted and a removable gripping flange.

[0032] 10) The system according to point 9), in which the cylinder has an open end into which the piston can be inserted and a joint end opposite the open end with a connector for a tubular guide element, the open end having an outwardly protruding annular shoulder, the connector being of the male "Luer Lock" type and comprising a cylindrical sleeve having an internal thread and a nozzle arranged coaxially within the cylindrical sleeve.

[0033] 11) A system according to points 9) or 10), wherein the piston has a body extending along a longitudinal axis between a proximal portion and a distal portion, preferably of a structure having flaps arranged in a cross shape.

[0034] 12) The system according to point 11), wherein the distal portion of the piston comprises a tip, a seal flange and a stop flange, and wherein when the syringe is pre-filled with the ferromagnetic agent and assembled, the stop flange is positioned flush with the annular shoulder of the cylinder, thereby determining the thrust position of the piston.

[0035] 13) A system according to any one of points 10) to 12), wherein the gripping flange has a recess sized to be coupled to the open end of the cylinder and a groove surrounding the recess and having a portion protruding toward the interior of the recess, the groove being configured to be inserted into the annular shoulder.

[0036] 14) An endoscopic examination kit comprising an endoscope guide according to any one of points 1) to 8), a syringe according to any one of points 9) to 13), and optionally a catheter.

[0037] 15) The kit according to point 14), in which said syringe is filled with said suspension of carbonyl iron.

[0038] 16) The kit of point 14), comprising a glass vial filled with the ferromagnetic agent as a powder and a syringe pre-filled with saline or comprising a glass vial with a suspension of the ferromagnetic agent and an empty syringe.

[0039] These two versions of the kit allow the powder to be stored for long periods of time.

[0040] The invention further relates to an endoscopy system, preferably a system for colonoscopy, as defined in the appended claims, comprising an endoscope guide according to the invention cooperating with an external magnetic field source, the magnetic field source being associated with a device that is preferably manually operable, i.e. without any moving device or auxiliary support. In a particular embodiment, the manually operable device is a handpiece, the magnetic field source of which is movable between an active position and a safe or rest position, in which in the active position the magnetic field source is close to the operating end of the handpiece and in which in the safe or rest position the magnetic field source is remote from the operating end of the handpiece.

[0041] Further features and advantages will become apparent from the description of preferred, but not exclusive, embodiments of the invention illustrated by way of non-limiting examples. [Brief description of the drawings]

[0042] [Figure 1A] FIG. 1A is a cross-sectional view of a first embodiment of a syringe for ferromagnetic fluid according to the present invention. [Figure 1B] FIG. 1B is a side view of the syringe of FIG. 1A in the direction A. FIG. [Diagram 2] FIG. 2 is a cross-sectional view of a detail of the syringe of FIG. 1A. [Diagram 3] FIG. 3 is a cross-sectional view of different details of the syringe of FIG. 1A. [Figure 4A] FIG. 4A is a perspective view of another detail of the syringe of FIG. 1A. [Figure 4B] FIG. 4B is a plan view of another detail of the syringe of FIG. 1A. [Diagram 5]FIG. 5 is a longitudinal cross-sectional view of the piston of the syringe of FIG. 1A. [Figure 6] FIG. 6 is a cross-sectional view of a tubular guide element of a system according to the invention. [Figure 7] FIG. 7 is a side view of the expandable container of the system of the present invention in an inflated state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] To better understand the present invention, it is first useful to explain how a diagnostic colonoscopy is performed.

[0044] A colonoscope is a flexible endoscope characterized by a tip (approximately 15 cm long), a body (approximately 130 cm long), and a manipulator. The tip is movable and houses the camera, the light, and the orifice of the operating channel. The tip can be manipulated by moving a knob located on the manipulator. The body is flexible and can be selected in certain models to perform certain endoscopic operations. The cables transmitting the images, the power supply, and the tie rods connecting the knob to the tip slide inside the body.

[0045] In addition to a knob for orienting the tip, the manipulator is also characterized by an external orifice for the manipulation channel, and by controls for aspirating or blowing air, and for recording images or videos.

[0046] Diagnostic colonoscopy aims to examine the entire surface of the colon mucosa to identify pathological changes that may require further diagnostic or therapeutic intervention. The tip of the colonoscope, equipped with a camera and a light, needs to reach the last part of the large intestine, called the cecum. If the instrument does not actually reach the cecum, the doctor cannot see if there are pathological changes in the unexplored part.

[0047] Positioning of the colonoscope is accomplished by an endoscope guide, which extends from the distal end of the colonoscope and moves forward into the lumen of the colonoscope to guide its passage until it has advanced as deeply as possible. Similar procedures are performed for introducing other endoscopes as well as for introducing catheters into the venous system.

[0048] Unlike other hollow tubular organs, such as the arteries, the large intestine has a large diameter and its walls can stretch for several centimetres, and in certain parts the organs can be mobile, sometimes up to 30 centimetres, into the abdominal cavity.

[0049] These anatomical features prevent the insertion of catheters or guides in sections longer than 10-30 cm. In fact, when a catheter is inserted into the rectum via the anus, it has a tendency to roll up on itself due to the large diameter of the lumen and the curvature of the viscera. Thus, unlike what is done in the field of blood vessels, catheterization of the large intestine is difficult to perform unless it is a short section. Catheters and endoscopic guides do not have sufficient mobility or sufficient resistance at the tip, even during X-ray examination. The resistance of an endoscope, catheter, or endoscopic guide means the ability to transmit thrust from the body of the instrument to the tip. The more rigid the endoscope, the higher the resistance. However, an endoscope that is too rigid cannot be easily maneuvered along the tortuous path of the large intestine. Colonoscopes are designed to be a compromise between sufficient flexibility and sufficient resistance.

[0050] However, if the colonoscope is excessively bent, its strength will gradually decrease. For example, if the colonoscope forms a loop during a colonoscopy, the colonoscope cannot transmit thrust from the body to the tip, and the endoscopist cannot advance the instrument and its camera further. In such a case, if the endoscopist pushes the instrument by hand, it will only transmit force to the wall of the organ, causing pain and risk of trauma, and the tip will not advance.

[0051] To overcome this drawback, an endoscope guide was proposed in the above-mentioned patent EP 3 399 901 A1 to the applicant, which makes it possible to carry out a method for introducing a colonoscope, said method comprising the steps of: introducing a distal end of a colonoscope through the patient's anus until a point of obstruction is reached, i.e., a point at which the colonoscope cannot be advanced; advancing the endoscopic guide to a distance of 4-10 cm past the distal end of the colonoscope; introducing a magnetic or ferromagnetic material into the expandable vessel of the endoscope guide such that the vessel reaches an expanded state; applying an external magnetic field by a magnetic field source to the region of the abdomen where the expandable container having the magnetic or ferromagnetic agent is located, attracting the container to a fixed point on the wall of the colon with a holding force of the magnetic or ferromagnetic agent of at least 5 Newtons in a lateral pulling direction; tensioning the endoscopic guide by applying a pulling force of at least 5 Newtons to a proximal end of the endoscopic guide; advancing the colonoscope to a fixation point on the container; repeating the above steps until a fixation point in the cecum is reached. Contains:

[0052] Pulling the endoscopic guide is intended to keep the guide tensioned, thus at least partially reducing the curvature of the colonic loop, even in this case, to facilitate sliding of the endoscope and facilitate the introduction of a relatively stiff endoscope.

[0053] As mentioned above, when carrying out the above mentioned method, the endoscopy system described in EP 3399901 A1 highlighted some important problems which made its use disadvantageous for diagnostic applications.The present invention was therefore born out of the need to overcome such important problems.

[0054] Next, the system according to the present invention will be described with reference to the drawings.

[0055] The endoscopy system according to the present invention is an endoscopic guide, in particular for a colonoscope, comprising a tubular guide element 1 and an anchor head 2, the tubular guide element 1 comprising a longitudinal cavity 3, the anchor head 2 comprising an expandable container 4 configured to accommodate a ferromagnetic agent, the expandable container 4 being in communication with said longitudinal cavity 3, the endoscopy system further comprising a ferromagnetic agent configured to be movable within said longitudinal cavity for filling / emptying the expandable container 4.

[0056] In a preferred embodiment, the system further comprises a syringe 5 pre-filled with the above-mentioned ferromagnetic agent, or a syringe pre-filled with saline, and a vial with the ferromagnetic agent as a powder for reconstituting the mixture before the endoscopic procedure, or a vial with a suspension of the ferromagnetic agent, and an empty syringe which is filled before the endoscopic procedure by aspirating the mixture from the glass vial.

[0057] The tubular guide element 1 has a proximal end 1a adjacent to the operator, and a distal end 1b.

[0058] The anchor head 2 can be located at or adjacent to the distal end 1b of the tubular guide element 1, while a connecting device 6 is located at the proximal end 1a, preferably removably connected to the tubular guide element 1. The connecting device 6 is configured to be removably connected to said pre-filled syringe 5.

[0059] According to the invention, the tubular guide element 1 has at least one longitudinal cavity 3 and the anchor head 2 is provided with an expandable reservoir 4 for containing said ferromagnetic agent.

[0060] The tubular guide element 1 preferably has a single lumen (i.e. only one longitudinal cavity 3), but in some variations has further cavities (e.g. two cavities in the case of a dual lumen) for the passage of air, fluid or endoscopic accessories, in which case it may be provided with a sheath defining each further lumen, which sheath may terminate beyond the anchor head 2.

[0061] It is important that the endoscope guide has a sufficiently wide lumen so that the ferromagnetic agent can flow quickly and easily while reducing kinking. In this regard, the tubular guide element 1 of the endoscope guide of the present invention preferably has an outer diameter D of less than 2.6 mm and an inner diameter of the lumen of the tubular guide element 1 of 1.6 mm to 1.75 mm.

[0062] In a particularly preferred embodiment, the tubular guide element 1 has an outer diameter of about 2.5 mm and an inner diameter of about 1.7 mm, resulting in a wall thickness S of about 0.4 mm. This sizing is particularly advantageous both in terms of reducing kinking and in terms of insertion into flexible optical endoscopes with diameters starting from 3.2 mm. The term "about" means more or less dimensional variation within the bounds of normal measurement or manufacturing tolerances.

[0063] Instead, the overall length of the tubular guide element 1 is preferably such that the catheter can be exchanged for another catheter, e.g. a catheter of a different type, during the process. Typically, the tubular guide element 1 is between 2.5 and 4 meters in length.

[0064] The expandable reservoir 4 is arranged in communication with the longitudinal cavity 3 of the tubular guide element 1 .

[0065] In a preferred embodiment, the mutual arrangement of the container 4 and the tubular guide element 1 is as shown, i.e., the expandable container 4 is positioned adjacent to the distal end of the tubular guide element 1 which traverses the expandable container 4 and protrudes therefrom with an end 1c.

[0066] The length of the end 1c may vary from a few millimeters to several centimeters and, in the second case, is preferably soft and flexible so as not to injure the mucosa if the guide is pressed against the wall of the internal organ.

[0067] In this embodiment, the expandable reservoir 4 thus extends around the tubular guide element 1 and completely surrounds it over at least a given axial length.

[0068] In another embodiment (not shown), the expandable reservoir 4 is instead positioned to cover the distal end 1 b of the tubular guide element 1 which opens into the retractable reservoir 4 .

[0069] The expandable container 4 is expandable and contractible manually, preferably elastically, so as to switch from a contracted state in which it is substantially attached to the body portion of the tubular guide element 1 to an expanded state in which it protrudes externally from the body portion of the tubular guide element 1, or vice versa, and is switched from the contracted position to the expanded position, or vice versa, by filling or emptying the expandable container 4 with a ferromagnetic agent.

[0070] The expandable container 4 comprises or alternatively consists of an expandable balloon. The retractable balloon can be elastic, semi-elastic or inelastic. Examples of expandable balloons are those commonly used in endoscopy, for example nylon balloons or balloons made of polyether-polyamide block copolymers or composites with polyamides. Such copolymers with polyamides and their compounds are known and are described in detail in patent publication WO2007 / 132485A1.

[0071] In a preferred embodiment, the expandable container 4 is sized to have a volume of 22-28 ml, more preferably about 25 ml, a length of 55-65 mm, more preferably about 60 mm, and a transverse diameter of 20-30 mm, more preferably about 25 mm, when in the expanded state, so as not to obstruct the lumen of the large intestine, the diameter of which varies between 3 and 7 cm depending on the cross-section observed.

[0072] Optionally, the tubular guide element 1 is provided with a valve arranged upstream of the expandable container 4, i.e. closer to the operator, and adapted to prevent backflow of the ferromagnetic agent when the expandable container 4 is filled with the ferromagnetic agent.

[0073] The Applicant has discovered, after lengthy and precise experiments, that the ferromagnetic agent most suitable for the purposes of the present invention is an aqueous suspension of so-called carbonyl iron.

[0074] Carbonyl iron is a high purity iron (97.5% for grade S and at least 99.5% for grade R) prepared by chemical decomposition of purified pentavalent carbonyl iron. It usually appears as a gray powder consisting of spherical particles. Most of the impurities are carbon, oxygen, and nitrogen. Its most common uses are in powder metallurgy, metal injection molding, and various specialty products. Carbonyl iron powder is used medicinally to treat iron deficiency and as an iron food supplement due to its low toxicity.

[0075] For the purposes of the present invention, the particle size profile is preferably D10=3-4.5 microns, more preferably about 4.1 microns; D50=5-10 microns, more preferably about 9.5 microns; D90 = 4-30 microns, more preferably about 26 microns Carbonyl iron is used.

[0076] The particle size of the ferromagnetic particles is Direct observation using an electron microscope, Measurement by the method of "laser light scattering" of aqueous suspensions using a particle size laser analyzer (Malvern Mastersizer 3000) and the LALLS (low angle laser light scattering) technique using Fraunhofer calculation theory. etc. can be measured by known methods.

[0077] The aqueous suspension of carbonyl iron according to the present invention is preferably a suspension in which carbonyl iron is present in purified water at 45% to 60% by weight, preferably 50% to 55% by weight, more preferably 52% to 53% by weight, based on the total weight of the suspension. Preferably, the aqueous suspension further contains 2.5% to 4.5% by weight of tribasic sodium citrate based on the total weight of the suspension, and / or 5% to 8% by weight of sodium chloride based on the total weight of the suspension.

[0078] The tribasic sodium citrate aids in the dispersion of the carbonyl iron particles in the suspension.

[0079] Sodium chloride acts to inhibit bacterial growth.

[0080] The aqueous suspension of carbonyl iron is preferably degassed, for example by bubbling with an inert gas such as nitrogen or argon, so as to avoid oxidation processes of the iron due to oxygen absorbed in the water.

[0081] The syringes are preferably vacuum packed under an inert gas atmosphere such as nitrogen or argon, and the bags used have an aluminum coating to limit the passage of oxygen.

[0082] The use of the aqueous suspension of carbonyl iron according to the invention is mentioned to have several advantages over known solutions, namely: i) increased magnetic response, which allows for reduced usage of aqueous dispersion and therefore less filling of the expandable container 4; ii) the particles are spherical, resulting in a lower viscosity aqueous suspension, reducing the risk of cluster and / or agglomerate formation; iii) Carbonyl iron is widely available in the market, has moderate cost and low toxicity, making it suitable for pharmaceutical use.

[0083] Therefore, many of the problems arising in known endoscopy systems are solved by the use of an aqueous suspension of carbonyl iron according to the invention, in particular by increasing the speed for filling and emptying the expandable container 4 (equal attractive forces due to the lower viscosity of the suspension and the smaller amount of suspension required), reducing the operator's efforts (lower viscosity of the suspension and the smaller amount of fluid to be delivered by the syringe) and reducing the risk of kinking of the tubular guide element 1 (smaller internal diameter due to the lower viscosity of the aqueous suspension of a ferromagnetic agent and the smaller amount of suspension required).

[0084] The endoscopy system of the present invention includes an endoscope guide as described above, and further includes an external magnetic field source configured to apply a retaining force to the ferromagnetic agent of greater than 5 Newtons in a transverse pulling direction at a distance of 2 centimeters to 10 centimeters.

[0085] The term "applying a holding force to a ferromagnetic agent against a transverse pulling direction" means a holding force on the ferromagnetic agent against a pull that is substantially perpendicular to the direction of maximum attractive force between the magnet and the ferromagnetic material as determined by the field lines of the magnetic field.

[0086] The holding force of the expandable container 4 against the wall of the colon, which should be greater than 5 Newtons in the transverse pulling direction to allow sufficient pulling of the endoscope guide as described above, depends on both the amount of ferromagnetic agent in the container 4 and the applied magnetic field, which in turn depends on the distance from the source of the magnetic field to the ferromagnetic agent-filled container 4. Typically, such a distance is 2-5 cm for most colon segments. However, this distance is larger in obese patients, for example up to 10 cm.

[0087] The source of the external magnetic field is selected as a function of the type of use of the instrument and the type of patient. Permanent magnets or electromagnets can be used, the former being preferred. For the purposes of the present invention, it is possible to use a magnetic field equivalent to that produced by a permanent magnet of magnetization grade N45 (i.e. a magnet whose maximum magnetic energy per volume that can be stored in the magnet is 45 Megagauss Orsted) in the form of a disk with a diameter of 50-80 mm and a thickness of 30-60 mm. If a permanent magnet is used, it can be made of sintered neodymium, sintered ferrite, plasted neodymium, etc.

[0088] The magnetic field source may preferably be contained in a handpiece specially adapted for this application, such as that described in EP 3399901 A1.

[0089] In a preferred embodiment, the step of applying the magnetic field may be performed by applying such a magnetic field in a stepwise manner. If the magnetic field required in practice were applied too quickly, the container 4 would move suddenly and the patient's internal organs would be stretched suddenly and painfully. The stepwise application of the magnetic field is A) Increasing the applied magnetic field by gradually changing the distance of the external magnetic field source; B) Gradually introducing an aliquot of the ferromagnetic agent into the expandable container 4 while the external magnetic field is already applied. It can be obtained in two ways:

[0090] As can be appreciated, the use of a handpiece specially adapted for this application is preferred, but not essential for the correct use of the endoscope guide of the present invention. In fact, the magnetic field source can be located on a plate or other device fixed above the patient's bed, or can be movably placed above it under manual or automatic control. For example, the permanent or electromagnetic magnetic field source can be connected to a movable arm, e.g. an articulated arm, which can be put into operation by manually operating it, or by controlling its movement by an electric actuator, or automatically operating according to a preselected operating program.

[0091] As mentioned before, the introduction of the ferromagnetic agent occurs by means of a syringe. Emptying of the container 4 can also be obtained in a similar manner.

[0092] A syringe particularly adapted for the purposes of the present invention is shown in FIGS. 1A-5.

[0093] Such a syringe is generally designated by the reference numeral 5 and comprises a cylinder 7 into which a piston 8 is slidably inserted, and a removable gripping flange 9 .

[0094] The cylinder 7 has an open end 7a into which a piston 8 can be inserted and a connecting end 7b opposite the open end 7a and provided with a connector 10 having a connecting device 6 of the tubular guide element 1.

[0095] The open end 7a of the cylinder 7 has an outwardly projecting annular shoulder 11.

[0096] The connector 10, shown in detail in FIG. 3, is preferably of the male "Luer Lock" type and includes a cylindrical sleeve 12 having an internal thread 12a and a nozzle 13 coaxially disposed within the cylindrical sleeve 12.

[0097] The cylinder 7 has a total volume larger than the fill volume (i.e. the volume occupied by the ferromagnetic agent) to facilitate the emptying operation. Preferably, the total capacity is about 35 ml when the fill volume is about 25 ml.

[0098] The piston 8 has a body portion 8a extending longitudinally between a proximal portion 8b and a distal portion 8c, and preferably comprises a structure 14 having flaps arranged in a cross shape to reduce friction with the inner wall of the cylinder 7 and to form a rigid structure.

[0099] The proximal portion 8b has a thrust button 15 of generous dimensions to allow the operator to apply appropriate pressure. For example, the thrust button 15 may have dimensions of 40mm x 25mm.

[0100] Distal portion 8c has tip 16a, seal flange 16b and stop flange 16c. When syringe 5 is pre-filled with ferromagnetic agent and assembled, stop flange 16c is positioned flush with annular shoulder 11 of cylinder 7, thereby determining the thrust position of piston 8.

[0101] The gripping flange 9, as shown in FIGS. 4A and 4B, has a planar shape, for example an ellipse, and has a flap 17 arranged alongside a recess 18.

[0102] The gripping flange 9 also has a groove 19 surrounding the recess 18 and has a portion 19 a that protrudes toward the inside of the recess 18 .

[0103] The gripping flange 9 is assembled to the pre-filled syringe by inserting the recess 18 into the open end 7 a of the cylinder 7 such that the annular shoulder 11 is inserted into the groove 19 .

[0104] As shown in FIG. 2, gripping flange 9 not only forms a gripping surface for the operator's index and middle fingers when operating the syringe with the thumb resting on thrust button 15, but also enables piston 8 to be held in place by abutment between stop flange 16c of cylinder 7 and protruding portion 19a of gripping flange 9, preventing it from slipping out of cylinder 7.

[0105] The gripping flange 9 is of ample dimensions to allow a comfortable and secure grip by an operator, for example the gripping flange has dimensions of 65mm x 36mm.

[0106] Syringe 5 may be made, for example, of polycarbonate (eg, a material called Makrolon®) or cyclic olefin (co)polymer (designated by the acronyms COP and COC, respectively).

[0107] The invention further relates to an endoscopy kit comprising an endoscopy guide according to the invention, a syringe 5 filled with a pre-set amount of an aqueous suspension of carbonyl iron, and optionally a catheter.

[0108] Another variant of the kit according to the invention comprises: A kit comprising a glass vial filled with a powdered ferromagnetic agent and a pre-filled syringe filled with saline (aqueous solution of NaCl and / or sodium citrate); or A kit comprising a glass vial containing a suspension of a ferromagnetic agent and an empty syringe, It is.

[0109] In a particular embodiment of the kit of the present invention, the syringe 5 is pre-dosed with a suspension of carbonyl iron as described above, preferably in a volume of 20-30 ml, more preferably about 25 ml.

[0110] Obviously, the endoscopy system according to the invention can be operated in exactly the same way as the endoscopy system described in EP 3399901 A1 according to the above mentioned method, which is a further object of the present invention.

[0111] In short, the present invention has found how to achieve the preset task and object by providing an endoscopic guide, in particular for colonoscopes, which allows diagnostic analysis or surgical intervention to remove lesions of the colon to be performed in a fast and complete manner, due to the fact that the colonoscope can be inserted up to the maximum point of the cecum by tensioning the guide. Such tensioning is made possible by the strong fixation obtained by the guide of the present invention, resulting in a considerable amount of ferromagnetic agent that can be introduced into the expandable container 4 and an increased magnetic field that can be applied externally by a handpiece or other magnetic or electromagnetic magnetic field source.

[0112] Furthermore, the endoscope guide can perform at least small movements of the anchor head 2 even when the anchor head 2 is in the occluded position. Indeed, in this regard, the operator can use an external magnetic field to move the anchor head to the appropriate position.

[0113] Furthermore, the operator has available an endoscopic guide which is sufficient to remain in a limited area of ​​the lumen of the organ being introduced to ensure stable fixation, and thus does not have to occlude the entire lumen.

[0114] Last but not least, it has been found that the endoscopic guide and the system comprising such a guide are relatively quick to operate, relatively affordable and easy to manufacture. The risk of kinking of the endoscopic guide is significantly reduced, the viscosity of the aqueous suspension of carbonyl iron is sufficiently low so that the time required to fill and empty the expandable container 4 is short and the effort of the operator is limited, and the risk of formation of clusters and / or agglomerates of the ferromagnetic particles is also low.

[0115] Finally, the guide and the system are relatively safe in case of failure during the performance of the examination: aqueous suspensions of carbonyl iron have low toxicity and are already used in the medical field as iron supplements. This eliminates the risk to the patient in case the expandable container 4 is lost.

[0116] A further advantage of the present invention relates to the possibility of more accurately locating lesions, for example in the case of colonoscopy, and indeed locating (topographically) on the patient's abdomen the location where the colonic lesion was found. Indeed, during use the external handpiece is magnetically coupled to the guide head at the point on the abdominal surface closest to the anchor head, which can advantageously be used to highlight where the lesion is located relative to the abdominal surface.

[0117] Although only some specific embodiments of the invention have been described, it is clear that a person skilled in the art can make all the modifications necessary to adapt it to a particular application, without departing from the scope of protection of the invention.

[0118] In practice, the materials used, as well as incidental dimensions and shapes, may vary according to the demands and advances of the art, provided they are suited to a particular application.

Claims

1. Endoscopic examination system, particularly a system for colonoscopy, An endoscopy system, particularly for colonoscopy, comprising an endoscope guide having a tubular guide element (1) and an anchor head (2), wherein the tubular guide element (1) has a longitudinal cavity (3), the anchor head (2) comprises an expandable container (4) configured to contain a ferromagnetic material, the expandable container (4) is in communication with the longitudinal cavity (3), and the endoscopy system further comprises a ferromagnetic material configured to be movable within the longitudinal cavity for filling / emptying the expandable container (4), wherein the ferromagnetic material is an aqueous suspension of carbonyl iron.

2. The system further includes a magnetic field source configured to apply a coercive force of 5 Newtons or more to the ferromagnetic material in the transverse tensile direction at a distance of 2 to 10 centimeters from the ferromagnetic material. The endoscopic examination system according to claim 1.

3. The system further includes a syringe (5) pre-filled with the aforementioned ferromagnetic agent. The system according to claim 1 or 2.

4. The carbonyl iron has a purity of 97.5% or higher, or 99.5% or higher, and its particle size profile is D10 = 3-4.5 microns or approximately 4.1 microns. D50 = 5-10 microns or approximately 9.5 microns. D90 = 4-30 microns or approximately 26 microns It consists of spherical particles, The system according to claim 1 or 2.

5. The aqueous suspension of carbonyl iron contains carbonyl iron in an amount of 45% to 60% by weight, or 50% to 55% by weight, or 52% to 53% by weight, based on the total weight of the suspension. The system according to claim 1 or 2.

6. The aqueous suspension of carbonyl iron contains 2.5% to 4.5% by weight of tribasic sodium citrate and / or 5% to 8% by weight of sodium chloride based on the total weight of the suspension. The system according to claim 1 or 2.

7. The tubular guide element (1) has a single lumen, an outer diameter (D) of less than 2.6 mm or about 2.5 mm, and an inner diameter (d) of the lumen of the tubular guide element (1) of 1.6 mm to 1.75 mm or about 1.7 mm. The system according to claim 1 or 2.

8. The expandable container (4) is equipped with or consists of an expandable balloon, has a capacity of 22 to 28 ml or about 25 ml, and is sized such that when expanded, its length is between 55 to 65 mm or about 60 mm, and its lateral diameter is between 20 to 30 mm or about 25 mm. The system according to claim 1 or 2.

9. The syringe (5) has a cylinder (7) into which a piston (8) is slidably inserted, and a removable gripping flange (9). The system according to claim 3.

10. The cylinder (7) has an open end (7a) into which the piston (8) can be inserted, and a connecting end (7b) on the opposite side of the open end (7a) that has a connector (10) for the tubular guide element (1), the open end (7a) has an annular shoulder (11) that protrudes outward, and the connector (10) is a male "Luer lock" type and has a cylindrical sleeve (12) having an internal thread (12a) and a nozzle (13) coaxially arranged inside the cylindrical sleeve (12). The system according to claim 9.

11. The piston (8) has a body portion (8a) that extends along the longitudinal direction between a proximal portion (8b) and a distal portion (8c), and preferably consists of a structure (14) having flaps arranged in a cross shape. The system according to claim 9.

12. The distal portion (8c) of the piston (8) has a tip portion (16a), a seal flange (16b), and a stop flange (16c), and the syringe (5) is pre-filled with the ferromagnetic agent, and when assembled, the stop flange (16c) is positioned at the same height as the annular shoulder portion (11) of the cylinder (7), thereby determining the thrust position of the piston (8). The system according to claim 11.

13. The gripping flange (9) has a recess (18) sized to fit onto the open end (7a) of the cylinder (7), and a groove (19) surrounding the recess (18) with a portion (19a) protruding toward the interior of the recess (18), wherein the groove (19) is configured to be inserted into the annular shoulder portion (11). The system according to claim 10.

14. An endoscopy kit comprising the endoscope guide described in Claim 1, the syringe (5) described in Claim 9, and optionally a catheter.

15. The syringe (5) is filled with the suspension of carbonyl iron. The kit according to claim 14.

16. A glass vial filled with the ferromagnetic agent as a powder, and a syringe pre-filled with physiological saline (an aqueous solution of NaCl and / or sodium citrate), or A glass vial containing the suspension of the ferromagnetic agent, and an empty syringe. Having, The kit according to claim 14.

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