Large-lumen self-tapping drainage port with custom-made high-ratio threads

Abstract

Systems, devices, and methods for installing a large-diameter drainage port to drain material from a patient. The systems and devices include a port, an installation handle, and / or an adapter. The port has tapered, asymmetrical threads to create an optimal amount of friction between the bone and the port during installation, allowing the port to be securely threaded into a borehole with a large diameter-to-depth ratio. The method includes rotating the port into the borehole using the installation handle and then attaching an adapter to the port. A negative pressure device in fluid communication with the adapter allows material to be drained from the patient through the large-diameter port.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This non-provisional application claims priority to U.S. Provisional Application No. 63 / 478,779, entitled "SYSTEMS AND DEVICES FOR LARGE BORE HOLE INTRACRANIAL ACCESS AND EVACUATION," filed January 6, 2023, by the same inventors. [Background technology]

[0002] 1. Field of the Invention The present invention relates generally to systems, devices, and methods for providing intracranial access. More particularly, the present invention relates to large-lumen evacuation ports and methods for creating large-bore access to improve surgical outcomes.

[0003] 2. Brief description of the prior art Chronic subdural hematoma (CSDH) represents a dangerous and potentially debilitating condition that affects a significant proportion of the population in the United States and worldwide, particularly the elderly. CSDH involves the collection of blood between the arachnoid and dura mater layers on the brain surface and can be caused by rupture of venous, arterial, and capillary networks. These ruptures can result from traumatic events and can be exacerbated by the use of antiplatelet and anticoagulant medications. Furthermore, CSDH can cause weakness, speech impairment, seizures, impaired consciousness, and death.

[0004] Currently, the annual incidence of CSDH worldwide ranges from 1 to 5 cases per 100,000; however, CSDH disproportionately affects the elderly population, with an annual incidence of 58 cases per 100,000 in those over 70 years of age. By 2030, 19% of the U.S. population is projected to be over 65 years of age, thereby increasing the number of people potentially affected by CSDH. Between 1998 and 2007, the annual hospitalization rate for treating subdural hematomas increased from 39 cases per 100,000 to 11.6 cases per 100,000, and the current estimated cost of such hospitalizations is $1.6 billion per year. CSDH is projected to become the most common condition requiring neurosurgical treatment by 2030.

[0005] Current CSDH drainage typically uses a 5 mm drainage port temporarily implanted within the patient to provide external access to the subdural hematoma. However, these smaller ports can often lead to clogging and incomplete drainage, which can subsequently lead to recurrence. Larger ports allow for better access and drainage, but it has been deemed impossible to secure these larger ports within the minimal bone depth available within the skull.

[0006] Therefore, what is needed is an evacuation port configured to be securely installed within a recessed hole having a large diameter and minimal depth. However, in view of the state of the art considered as a whole at the time this invention was made, it was not apparent to those skilled in the art how the shortcomings of the prior art could be overcome.

[0007] All referenced publications are incorporated herein by reference in their entirety. Furthermore, if the definition or use of a term in a reference incorporated herein by reference is inconsistent with or contradicts the definition of that term provided herein, the definition of that term provided herein shall apply and the definition of that term in the reference shall not apply.

[0008] Although certain aspects of the prior art have been discussed to facilitate disclosure of the present invention, applicants do not in any way reject these technical aspects, and it is contemplated that the claimed invention may encompass one or more of the prior art aspects discussed herein.

[0009] The present invention may address one or more of the problems and deficiencies of the prior art discussed above. However, it is believed that the present invention may prove useful in addressing other problems and deficiencies in several technology areas. Accordingly, the claimed invention should not be construed as necessarily limited to addressing any of the specific problems or deficiencies discussed herein.

[0010] Where any document, act, or item of knowledge is referenced or discussed in this specification, such reference or discussion is not an admission that that document, act, or item of knowledge, or any combination thereof, was publicly available, known to the public, part of the general knowledge, or constitutes prior art under any applicable legal provision or was known to be relevant to any attempt to solve any problem to which this specification pertains, at the priority date. Summary of the Invention

[0011] The long-standing and heretofore unmet need for improved systems, devices and methods for performing subdural hematoma evacuation is now met by a new, useful, and non-obvious invention.

[0012] The present invention includes an evacuation port having an internal lumen and an externally threaded portion. The threaded portion includes threads configured to engage the sidewall of an implantation hole having a diameter greater than its depth. In some embodiments, the threaded portion has a length along the longitudinal axis of the port between about 3 mm and about 6 mm and a minor diameter greater than the depth of the hole, e.g., in some cases about 6 mm or greater.

[0013] In some embodiments, the minor diameter is consistent throughout the threaded portion, and the minor diameter is equal to the diameter of the embedment hole when the evacuation port is embedded in the embedment hole, or is less than 1 mm smaller than the diameter of the embedment hole when the evacuation port is embedded in the embedment hole.

[0014] The threads on the port may further include a tapered portion that merges into a non-tapered portion when moving proximally. The tapered portion may taper at an angle between about 1° and about 20° and may extend less than 5 mm from the distal end of the port. The tapered portion may extend at least 2 mm, and the non-tapered portion may extend at least 2 mm. The threads may also include a variable root depth between adjacent crests of the threads and a consistent pitch.

[0015] The threads may have an asymmetric profile such that the upper flank angle is different from the lower flank angle, e.g., the upper flank angle may be greater than the lower flank angle. The upper flank angle may be between about 23° and about 40°, and the lower flank angle may be between about 1° and about 22°. The threaded portion may further include one or more self-tapping features cut into the tapered portion of the thread on the port. Some embodiments include longitudinally aligned columns of self-tapping features cut into the tapered portion of the thread.

[0016] The evacuation port further includes an attachment mechanism adjacent the proximal end configured to engage the port installation handle such that rotation of the port installation handle causes rotation of the port. The evacuation port is also configured to engage the adapter to form a fluid channel between the adapter and the port.

[0017] The present invention further includes a system and / or kit for draining material from a patient. The system / kit includes a port and an adapter. The port and adapter can be any of the designs described herein, including the designs described in the previous paragraph. The port is configured to be placed within an implanted hole formed in the patient and includes an internal lumen and an externally threaded portion. The threaded portion has threads with an asymmetric profile and includes a tapered portion connected to a non-tapered portion moving proximally. The threaded portion also includes a reduced diameter of about 6 mm or greater.

[0018] The adapter is configured to engage the proximal end of the port to form a fluid channel between the adapter and the port. The adapter further includes a hose attachment mechanism, which may be a hose barb, a luer fitting, or other attachment mechanism known in the art.

[0019] The system further includes a port placement handle configured to engage a portion of the port such that rotation of the port placement handle causes rotation of the port.

[0020] The present invention further includes a method of placing a port to evacuate material from a patient. The method includes rotating a port into a bore formed in a patient's bone, attaching an adapter to the port to form a fluid channel between the adapter and the port, operably coupling tubing to the adapter, and generating negative pressure through the tubing to evacuate material through the port, the adapter, and the tubing. In some embodiments, the step of rotating the port includes attaching a port placement handle to a portion of the port such that rotation of the port placement handle causes rotation of the port. Also, the port and adapter used in this method may be of any of the designs described herein.

[0021] These and other important objects, advantages and features of the present invention will become apparent as the present disclosure proceeds.

[0022] The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts exemplified in the disclosure hereinafter described, the scope of the invention being indicated in the claims.

[0023] For a more complete understanding of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0024] [Figure 1A] FIG. 10 is a perspective view of an evacuation port according to one embodiment of the present invention. [Figure 1B] FIG. 10 is an elevational view of an exhaust port according to one embodiment of the present invention. [Figure 1C] 1B shows highlighted detail B. [Figure 1D] FIG. 10 is an enlarged cross-sectional view of the threaded portion of one embodiment of the port. [Figure 1E] FIG. 10 is an exploded perspective view of an evacuation port and port plug according to one embodiment of the present invention. [Figure 1F] FIG. 10 is a cross-sectional view of an evacuation port and port plug according to one embodiment of the present invention. [Figure 2A] FIG. 1 is a perspective view of an installation handle according to one embodiment of the present invention. [Figure 2B] FIG. 10 is a cross-sectional view of an installation handle according to one embodiment of the present invention. [Figure 3A] FIG. 1 is a perspective view of an adapter according to one embodiment of the present invention. [Figure 3B] 1 is a cross-sectional view of an adapter according to one embodiment of the present invention. [Figure 3C] FIG. 1 is an exploded view of an adapter, according to one embodiment of the present invention. [Figure 3D] 1 is a cross-sectional view of an adapter secured to a port, according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] In the following detailed description of the preferred embodiment, reference is made to the accompanying drawings which form a part hereof, and which show, by way of illustration, specific embodiments in which the invention may be practiced. It is understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.

[0026] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally used in its sense including "and / or" unless the context clearly dictates otherwise.

[0027] All numerical designations, such as measurements, potencies, physical properties, strengths, and other designations (including ranges), are approximations that may vary up or down by increments of 1.0 or 0.1, as appropriate. It should be understood that all numerical designations are preceded by the term "approximately" or "about," even if not necessarily explicitly stated. As used herein, "approximately" or "about" refers to an acceptable error range for a particular value as determined by one of ordinary skill in the art, which is partially determined by how the value is measured or determined. For example, the term "about" may refer to ±10% of the numerical value.

[0028] As used herein, "subject" or "patient" is used to describe a human or other animal to which treatment is administered.

[0029] As used herein, "target area" is used to describe an area of ​​a subject requiring treatment, such as the skull of a subject experiencing symptoms resulting from a subdural hematoma.

[0030] The present invention includes systems, devices, and methods for placing a drainage port within a burr hole and evacuating material through the drainage port. In some embodiments, the drainage port is placed within a burr hole having a diameter-to-depth ratio greater than 1, allowing for more complete drainage of, for example, a subdural hematoma while reducing recurrence rates. Improved systems, devices, and methods for evacuating subdural hematomas are described in more detail in the following sections. While the present invention is described herein with respect to cranial surgery, it should be noted that the system, its components, and methods of use can be used in other patient anatomies and / or to perform other surgeries.

[0031] During development of the present invention, it was determined that placing a port in an implantation hole larger than 5 mm was prone to error and prevented the port from remaining securely in the bone. The reason for these problems was that the skull has a minimum thickness ranging from about 4.7 mm to about 14.7 mm, with an average thickness of about 8 mm. Therefore, it was determined that a very precise hole with a port having specific characteristics was required to be securely embedded in the skull. More specifically, it was determined that a specific small diameter relative to the inner diameter of the implantation hole and a specific set of thread characteristics were required for the port to remain securely embedded.

[0032] While the present application and drawings specifically refer to the implantable device as evacuation port 100, it should also be noted that alternative implantable devices with the same thread characteristics and clearances may be used to better attach the implantable device to bone or other objects. The various characteristics described herein allow port 100 to be inserted and secured in bones having minimal thicknesses. In other words, port 100 can be secured within implant holes having large diameter-to-depth ratios. Specifically, the present invention allows port 100 to be securely attached with diameter-to-depth ratios greater than 1, including, but not limited to, about 6:3, 7:3, 14:3, 15:3, and even up to 20:2.

[0033] The present invention includes an evacuation port 100 configured to be securely threaded into a recessed hole having a diameter-to-depth ratio of 1 or greater. In some embodiments, the present invention includes a system, or kit, or method that uses one or more of the following components: evacuation port 100, installation handle 200, and / or adapter 300.

[0034] 1, the evacuation port 100 includes a proximal end 102, a distal end 104, and an internal lumen 105 extending between the two ends. Once implanted, the evacuation port 100 provides the patient with access to an interior region through the internal lumen 105.

[0035] In one embodiment, the exit port 100 can be implanted for approximately 29 days or less. The exit port 100 is made from titanium, stainless steel, ceramic, polyetheretherketone (PEEK), combinations thereof, or similarly hard biocompatible materials. In one embodiment, the force required to rotate the exit port 100 (discussed in more detail below) can be increased by increasing the surface roughness of the exit port 100, such as by blasting the surface of the exit port 100 with oxides or glass beads.

[0036] The exhaust port 100 is sized and shaped such that the minor diameter of the exhaust port 100 (i.e., the diameter of the shaft from which the threads 110 extend outward) is less than or approximately equal to the diameter of the recessed hole, such that the exhaust port 100 is receivable within the recessed hole and the port 100 can self-orient to axially align with the recessed hole using the recessed hole's sidewalls. In one embodiment, the minor diameter of the exhaust port 100 is between about 6 mm and 16 mm. In some embodiments, the clearance between the recessed hole and the minor diameter of the port 100 is 0.25 mm. In some embodiments, the clearance between the recessed hole and the minor diameter of the port 100 is 1 mm or less.

[0037] To secure the evacuation port 100 within the interior sidewall defining the bore, the evacuation port 100 includes a helical thread 110 extending away from the body 108 of the evacuation port 100. Thus, upon insertion of the evacuation port 100 into the bore, the helical thread 110 engages and secures with the interior sidewall defining the bore, thereby forming a mechanical connection between the evacuation port 100 and the interior sidewall defining the bore. The high-ratio threads of the evacuation port 100 create an optimal amount of friction between the bone and the evacuation port 100, such that, in one embodiment, the evacuation port 100 is prevented from rotating with a force of less than about 2.1 Nm. In one embodiment, the friction is such that the evacuation port 100 is prevented from rotating with a force less than the maximum torque that an average human hand can exert through an object with a diameter of 2 inches (5.08 cm). However, it should be understood that other friction values ​​can be achieved depending on the desired rotational force threshold.

[0038] The helical thread 110 forms a series of ridges 106 and roots 107 about the longitudinal axis of the port 100. As best shown in FIG. 1C , at least a portion of the thread 110 tapers inward toward the central longitudinal axis of the port 100 moving distally. In other words, some of the ridges 106 have a smaller lateral extent moving toward the distal end 104, thereby forming a tapered portion 112 of the thread 110. The tapered portion 112 of the thread 110 is closer to the terminal distal end 104 of the exhaust port 100; therefore, when the distal end 104 of the exhaust port 100 is embedded in an embedding hole, the smaller outer diameter of the tapered majority of the thread 110 initially engages the sidewall of the embedding hole. As the tapered portion 112 engages the sidewall and the evacuation port 100 rotates during insertion, the greater lateral extent of the ridge 106 of the tapered portion 112 engages the sidewall of the recessed hole, thereby improving and facilitating placement of the evacuation port 100 within the recessed hole.

[0039] In some embodiments, the taper angle ω is approximately 7.5°. In some embodiments, the taper angle ω is between approximately 1° and 20°. Furthermore, the tapered portion 112 extends approximately 3 mm relative to the length of the port 100. In some embodiments, the tapered portion 112 extends at least 3 mm. In some embodiments, the tapered portion 112 extends in the range of approximately 2 mm to 5 mm.

[0040] Tapered portion 112 transitions to a non-tapered portion 114 to adequately secure port 100 to the surrounding bone within the implantation hole. Non-tapered portion 114 extends approximately 2 mm relative to the length of port 100. In some embodiments, non-tapered portion 114 extends at least 2 mm.

[0041] Additionally, to improve stability of the evacuation port 100 during placement, the body 108 of the port 100 includes a generally consistent minor diameter throughout the threaded portion. As previously discussed, the consistent minor diameter is approximately equal to or slightly smaller than the diameter of the borehole. Furthermore, in one embodiment, the threads 110, despite their consistent pitch, include variable root depths between the crests 116 resulting from the tapered portion 112. Thus, threaded portions with smaller crests have larger root sizes, and threaded portions with larger crests have smaller roots, similarly facilitating placement of the evacuation port 100 within the borehole. This variable root depth, created by the taper, improves the ability of the evacuation port 100 to continuously engage bone during placement.

[0042] Referring now to FIG. 1D , the thread profile is asymmetrical relative to a central axis extending from ridge 106 to body portion 108, such that upper flank angle ρ1 is not equal to lower flank angle ρ2. In some embodiments, upper flank angle ρ1 is greater than lower flank angle ρ2, and thus the thread is "backward sloping." In some embodiments, upper flank angle ρ1 is between about 23° and about 40°. In some embodiments, upper flank angle ρ1 is about 30°. In some embodiments, lower flank angle ρ2 is between about 1° and about 22°. In some embodiments, lower flank angle ρ2 is about 15°.

[0043] By varying the upper and lower flank angles, upon engagement between the exhaust port 100 and the interior sidewall of the recessed hole, the exhaust port 100 experiences greater pull-out strength compared to a standard thread profile, thereby reducing the likelihood of the exhaust port 100 dislodging in the absence of sufficient force. For example, in one embodiment, the pull-out force is 178 N or greater and the removal torque is 2.1 Nm or greater. In some embodiments, the upper and / or lower flank angles can vary over the length of the thread 110. In some embodiments, the upper and / or lower flank angles remain consistent over the length of the thread 110.

[0044] In one embodiment, the thread 110 includes one or more cutting flutes 118. The cutting flutes 118 function as a self-tapping feature to allow the thread 110 to engage bone within the sidewall of the implant hole. The cutting flutes 110 may be in the form of flute relief disposed throughout a portion of the thread 110. As shown in FIG. 1C, the cutting flutes 118 are disposed within a tapered section 112 where the thread 110 first encounters bone upon implantation.

[0045] In some embodiments, the cutting flutes 118 are circumferentially spaced around the port 100. The cutting flutes may be diametrically opposed and / or equally spaced around the circumference of the port 100. The cutting flutes 118 may be longitudinally offset along the same vertical line to form a "column" of aligned cutting flutes 118, as shown in FIG. 1C.

[0046] The cutting flutes 118 form air passages. Accordingly, some embodiments include cutting flutes 118 that lie below the outer surface of the patient's bone when the port 100 is fully implanted. As a result, at least a portion of the threads 110 without the cutting flutes 118 engages the bone to form a seal between the port 100 and the sidewall of the implantation hole. Accordingly, in some embodiments, the cutting flutes 118 extend approximately 3 mm or less from the distal end of the port 100 or the distal end of the threads 110. In some embodiments, the cutting flutes 118 extend approximately 4 mm or less from the distal end of the port 100 or the distal end of the threads 110. In some embodiments, the cutting flutes 118 extend approximately 5 mm or less from the distal end of the port 100 or the distal end of the threads 110.

[0047] During installation of the evacuation port 100 within the borehole, the distal end of the thread 110, which has the smallest major diameter, begins the installation process by beginning to thread into the interior sidewall defining the borehole. The continuous threading of the tapered portion 112 improves the pullout strength of the evacuation port 100. The threading of the non-tapered portion 114 is achieved with sufficient torque to overcome frictional forces, thereby securing the thread 110 deeper within the borehole with each subsequent threaded engagement.

[0048] Embodiments of the system may further include a port plug 120, shown in FIGS. 1E-1F. The port plug 120 has a proximal end 122 formed in part by a top disk 124 and a user-graspable structure 126 to allow for easy removal of the port plug 120. The port plug 120 further includes a distal end 128 having a body portion 130 extending between the top disk 124 and the distal end 128. One or more interference disks 132 are located between the top plate 124 and the distal end 128. The top plate 124 has a diameter larger than the diameter of the lumen 105, while the interference disks 132 are equal to or slightly larger than the diameter of the lumen 105 to seal the lumen 105. In some embodiments, the interference disks 132 and / or the plug 120 are constructed from an elastomeric or other flexible material capable of providing a sufficient seal.

[0049] Embodiments of the evacuation port 100 include an attachment mechanism 134 at or near the proximal end 102 of the port 100. The attachment mechanism 134 is configured to temporarily engage an external device. The attachment mechanism 134 may include a series of bayonet mounts 136 as shown in FIG. 1A, although it should be understood that the bayonet mounts 136 may have alternative shapes, sizes, and quantities.

[0050] The present invention also includes a medical device kit. The kit includes one or more of the evacuation port 100, installation handle 200, and / or adapter 300 having one or more of the features described herein. The installation handle 200 is configured to aid in aligning and securing the evacuation port 100 within the implantation cavity, as shown in FIG. 2 . To that end, the distal end 202 of the installation handle 200 is configured to engage the attachment mechanism 134 such that rotation of the installation handle 200 causes rotation of the port 100. This engagement can be achieved through an opening 204 in the distal end 202 of the installation handle 200. The opening 204 includes the receptacle necessary to secure one or more bayonet mounts 136 such that rotation of the installation handle 200 causes rotation of the port 100.

[0051] The attachment mechanism 134 is also configured to operably couple a negative pressure device such that the negative pressure device is configured to remove material (such as that associated with a subdural hematoma) from the implant hole and / or from the patient via the evacuation port 100. Some embodiments do this via an adapter 300, shown in FIG. 3 . The adapter 300 includes a proximal end 302 with a hose barb 304 or other component for fluidly connecting to a hose. The distal end 304 of the adapter 300 is configured to temporarily engage the evacuation port 100 to form a seal within the evacuation port 100. In one embodiment, engagement of the adapter 300 with the port 100 is sufficient to form a vacuum seal ranging from approximately 17 cmH2O to 100 cmH2O or greater.

[0052] In some embodiments, as best shown in FIG. 3C , adapter 300 is a multi-part structure including a barb insert 306, an O-ring 308, and a barb collar 310. Barb collar 310 includes a receiver for receiving attachment mechanism 118 of port 100 and a ramp structure 312 that compresses attachment mechanism 118 into O-ring 308 upon rotation of attachment mechanism 118 relative to barb collar 310. Insert 306 and barb collar 310 sandwich O-ring 308 and attachment mechanism 118 by operably engaging latches 311 on barb collar 310 with retention shoulders 314 on barb insert 306, as shown in FIG. 3D . The outer surface of barb collar 310 can further include a series of surface protrusions to allow for better grip while rotating barb collar 310 relative to port 100.

[0053] It should be understood that other devices can be attached to the exhaust port 100 after installation. Additionally, it should be understood that other attachments can be used to secure these devices to the exhaust port 100, such as through a bayonet mount, undercut, ledge, threads, press fit, or other similar mechanical connection.

[0054] The present invention further includes a method for placing a large bore port within a patient's body and evacuating material from the patient. The method includes rotatably securing the large bore port within an implantation hole within the patient's body at a target site, such as the patient's head. The port may be designed according to port 100, as described herein. The port is rotated until any cutting flutes in the threads are located below the outer surface of the implantation hole.

[0055] The step of rotating the port into the borehole can be accomplished by first attaching an installation handle, such as installation handle 200 described herein, and then rotating the handle, thereby rotating the port. Once the port is fully threaded into the borehole, the method of evacuating material further includes attaching an adapter to the exposed proximal end of the port. The adapter may be designed according to adapter 300 as described herein. If a hose is not already secured to the adapter, the method further includes attaching the hose to the adapter. A negative pressure device is secured to the hose to draw material through a fluid channel formed by the tubing, the adapter, and the port. The negative pressure device is then activated to generate negative pressure to remove material from the patient through the fluid channel.

[0056] The advantages set forth above and those made apparent from the foregoing description are effectively attained. Since certain changes can be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.

[0057] It is also to be understood that the following claims are intended to encompass all of the generic and specific features of the invention described herein, and all statements of the scope of the invention that may be linguistically said to lie therebetween.

Claims

1. 1. An evacuation port configured to be implanted within a patient's head, said evacuation port comprising: an internal lumen; Male thread part and wherein the threaded portion comprises: a thread having a tapered portion leading to a non-tapered portion moving in a proximal direction; Small diameter of about 6 mm or more and a discharge port.

2. 10. The exhaust port of claim 1, further comprising a variable root depth between adjacent thread crests and a consistent pitch.

3. 10. The evacuation port of claim 1, further comprising an attachment mechanism adjacent a proximal end, the attachment mechanism configured to engage the port placement handle such that rotation of the port placement handle causes rotation of the port.

4. The exhaust port of claim 1 , wherein the minor diameter of the port is uniform throughout the threaded portion.

5. The exhaust port of claim 1 , wherein the threads on the port are asymmetrical such that the upper flank angle is greater than the lower flank angle.

6. The exhaust port of claim 1 , wherein the upper flank angle is between about 23° and about 40°.

7. The exhaust port of claim 1 , wherein the lower flank angle is between about 1° and about 22°.

8. The exhaust port of claim 1 , further comprising one or more self-tapping features cut into the tapered portion of the threads.

9. 10. The exhaust port of claim 1, further comprising a longitudinally aligned column of self-tapping features cut into the tapered portion of the threads.

10. 2. The exhaust port of claim 1, wherein the tapered portion of the thread extends longitudinally for at least 2 mm.

11. 2. The exhaust port of claim 1, wherein the non-tapered portion of the thread extends longitudinally for at least 2 mm.

12. The exhaust port of claim 1 , wherein the tapered portion of the threads has a taper angle of between about 1° and 20°.

13. 2. The exhaust port of claim 1, wherein the minor diameter is equal to the diameter of the recess when the exhaust port is recessed in the recess, or less than 1 mm smaller than the diameter of the recess when the exhaust port is recessed in the recess.

14. 1. A system for draining a substance from a patient, the system comprising: a port configured to be placed within an implantation cavity formed in the patient, an internal lumen; Male thread part and and wherein the threaded portion comprises: a thread having an asymmetric profile and including a tapered portion connected to a non-tapered portion moving in a proximal direction; Small diameter of about 6 mm or more a port; an adapter configured to engage a proximal end of the port to form a fluid channel between the adapter and the port, the adapter further including a hose attachment mechanism; A system comprising:

15. The system of claim 14 , wherein the hose attachment mechanism is a hose barb.

16. The system of claim 14 , further comprising a port placement handle configured to engage a portion of the port such that rotation of the port placement handle causes rotation of the port.

17. 15. The system of claim 14, wherein the tapered portion tapers at an angle between about 1° and about 20°.

18. 15. The system of claim 14, wherein the tapered portion of the thread extends at least 2 mm relative to the length of the port.

19. 15. The system of claim 14, wherein the non-tapered portion of the thread extends longitudinally for at least 2 mm.

20. 15. The system of claim 14, wherein the threads on the port have an upper flank angle that is greater than a lower flank angle.

21. 15. The system of claim 14, wherein the upper flank angle is between about 23° and about 40°.

22. 15. The system of claim 14, wherein the lower flank angle is between about 1° and about 22°.

23. 15. The system of claim 14, wherein the port further includes one or more self-tapping features cut into the tapered portion of the threads on the port.

24. 15. The system of claim 14, further comprising a longitudinally aligned column of self-tapping features cut into the tapered portion of the thread.

25. 15. The system of claim 14, wherein the threads on the port have a variable root depth between adjacent thread crests and a consistent pitch.

26. The system of claim 14 , wherein the minor diameter of the port is uniform throughout the threaded portion.

27. 15. The system of claim 14, wherein the smaller diameter is equal to the diameter of the recess when the exhaust port is recessed in the recess, or is 1 mm or less smaller than the recess when the exhaust port is recessed in the recess.

28. 1. A method of draining a substance from a patient, the method comprising: rotating a port into an implantation hole formed in the patient's bone, the port comprising: an internal lumen; Male thread part and wherein the threaded portion comprises: a thread having an asymmetric profile, the thread including a tapered portion connected to a non-tapered portion; a small diameter greater than the depth of the embedding hole; rotating the port, attaching an adapter to the port to form a fluid channel between the adapter and the port; operably coupling a tube to the adapter; generating a negative pressure through the tubing to expel material through the port, the adapter, and the tubing; A method comprising:

29. 30. The method of claim 28, wherein rotating the port includes attaching the port placement handle to a portion of the port such that rotation of the port placement handle causes rotation of the port.

30. 30. The method of claim 28, wherein the tapered portion of the threads on the port tapers at an angle between about 1° and about 20°.

31. 29. The method of claim 28, wherein the tapered portion of the threads on the port extends at least 2 mm relative to the length of the port.

32. 29. The method of claim 28, wherein the non-tapered portion of the threads on the port extends longitudinally for at least 2 mm.

33. 29. The method of claim 28, wherein the threads on the port have an upper flank angle that is greater than a lower flank angle.

34. 34. The method of claim 33, wherein the upper flank angle is between about 23° and about 40°.

35. 34. The method of claim 33, wherein the lower flank angle is between about 1° and about 22°.

36. 30. The method of claim 28, wherein the port further includes one or more self-tapping features cut into the tapered portion of the threads on the port, and the port is rotated until the one or more self-tapping features are located below an outer surface of the recessed hole.

37. 30. The method of claim 28, wherein the port further comprises a longitudinally aligned column of self-tapping features cut into the tapered portion of the threads.

38. 29. The method of claim 28, wherein the threads on the port have a variable root depth between adjacent thread crests and a consistent pitch.

39. 29. The method of claim 28, wherein the minor diameter of the port is uniform throughout the threaded portion.

40. 29. The method of claim 28, wherein the smaller diameter is equal to the diameter of the embedment hole when the evacuation port is embedded in the embedment hole, or is 1 mm or less smaller than the embedment hole when the evacuation port is embedded in the embedment hole.

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