Claims:WE CLAIM
1. A cerebral protection system comprising:
• an outer sheath including a proximal end, a distal end and a lumen;
• an inner tube including a proximal end, a distal end and a lumen, the inner tube being provided inside the lumen of the outer sheath;
• a trans aortic catheter including a proximal end and a distal end, the trans aortic catheter being provided inside the lumen of the inner tube;
• a handle including a switch, the handle being attached at the proximal end of the inner tube and the outer sheath;
• a mesh including a proximal end and a distal end, the mesh being attached towards the distal end of the inner tube;
• a primary thread being connected to the distal end of the mesh on one end and the switch of the handle on another end, the primary thread being present inside the lumen of the inner tube;
wherein a clockwise or anticlockwise rotation of the switch results in opening or closing of the distal end of the mesh respectively.
2. The cerebral protection system as claimed in claim 1 wherein the primary thread is connected to the distal end of the mesh using a plurality of secondary threads.
3. The cerebral protection system as claimed in claim 1 wherein the proximal end of the mesh is attached by means of crimping.
4. The cerebral protection system as claimed in claim 3 wherein the proximal end of the mesh includes a marker.
5. The cerebral protection system as claimed in claim 1 wherein the mesh has a pore size in range of 10 µm to 400 µm.
6. The cerebral protection system as claimed in claim 1 wherein the trans aortic catheter includes a balloon expandable heart valve. , Description:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(Section 10 and Rule 13)

1. TITLE OF THE INVENTION:
CEREBRAL PROTECTION SYSTEM

2. APPLICANTS:
Meril Life Sciences Pvt Ltd, an Indian company, of the address Survey No. 135/139 Bilakhia House Muktanand Marg, Chala, Vapi-Gujarat 396191

3. The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF INVENTION
[1] The present disclosure relates to a medical device, more specifically relates to a cerebral protection system.
BACKGROUND
[2] Accumulation of calcium in a native heart valve gradually increases with age which leads to formation of a stenosed heart valve. Such a condition is termed as aortic valve stenosis or aortic stenosis (AS). If the stenosed heart valve is not replaced, it may cause fatal consequences like inefficient pumping of blood or complete heart arrest in some cases. Currently, a process named transcatheter aortic valve replacement (TAVR) is recognized as the most credible method for replacing stenosed heart valve owing to the fact that it is a minimally invasive procedure.
[3] However, while replacing the stenosed heart valve via the TAVR process, break down of calcium particles of the stenosed heart valve may take place. Such calcium particles may be released in the bloodstream and block carotid and/or other arteries that cause fatal consequences such as a stroke. For example, the calcium particles may travel to the brain along the bloodstream and cause brain haemorrage. Therefore, to prevent the migration of calcified particles to the carotid and/or other arteries, various cerebral protection devices are used.
[4] Though cerebral protection devices are intended to overcome the disadvantages of TAVR, the conventionally utilized cerebral protection devices pose threats to the human body. The conventional cerebral protection devices do not have adequate closure arrangement post capturing of the emboli. Such insufficiency may result in the release of the captured emboli, back into the arteries during retrieval of the cerebral protection device from the human body.
[5] Further, in conventional devices, apart from a puncture for deploying an artificial heart valve, an additional puncture is required for introduction of a cerebral protection device into the human body. In such cases, a large amount of contrast media (dye) is required, which may have ill effects on kidney of a patient leading to renal damage or renal failure. Handling said two punctures at the same time may be tedious, complex and also may require a superior technical expertise. Further, due to dual puncture, the chances of infection, stroke, blood loss and/or local vascular injury may also increase. In addition to this, the major disadvantage of the conventional cerebral protection systems is that they fail to cover all sub arteries at aorta. Hence, efficient avoidance of migration of the emboli is not achieved.
[6] Therefore, there exists a need for an improved cerebral protection system which overcomes the hurdles offered by existing systems.
SUMMARY
[7] The present invention discloses a cerebral protection system. The cerebral protection system includes an outer sheath including a proximal end, a distal end and a lumen, an inner tube including a proximal end, a distal end and a lumen. The inner tube being provided inside the lumen of the outer sheath. A trans aortic catheter including a proximal end and a distal end, the trans aortic catheter being provided inside the lumen of the inner tube. A handle including a switch, the handle being attached at the proximal end of the inner tube and the outer sheath. A mesh including a proximal end and a distal end, the mesh being attached towards the distal end of the inner tube. A primary thread being connected to the distal end of the mesh on one end and the switch of the handle on another end, the primary thread is present inside the lumen of the inner tube. Further, the clockwise or anticlockwise rotation of the switch results in opening and closing of the distal end of the mesh respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
[8] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale.
[9] FIG. 1 illustrates a cross-sectional side view of a cerebral protection system in accordance with an embodiment of the present invention.
[10] FIG. 2 illustrates the position of the mesh of the cerebral protection system in aorta after deployment in accordance with an embodiment of the present invention.
[11] FIG. 3 illustrates the handle of the cerebral protection system mechanism in accordance with an embodiment of the present invention.
[12] FIG. 4 represents a structural arrangement of the mesh in accordance with an embodiment of the present invention.
[13] Fig. 5 illustrates a flow chart of the process in accordance with an embodiment of the present invention.
[14] FIG. 6a-b illustrates the cerebral protection system in different stages during the deployment process.
DETAILED DESCRIPTION OF THE INVENTION
[15] Prior to describing the invention in detail, definitions of certain words or phrases used throughout this patent document will be defined: the terms "include" and "comprise", as well as derivatives thereof, mean inclusion without limitation; the term "or" is inclusive, meaning and/or; the phrases "coupled with" and "associated therewith", as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have a property of, or the like; Definitions of certain words and phrases are provided throughout this patent document, and those of ordinary skill in the art will understand that such definitions apply in many, if not most, instances to prior as well as future uses of such defined words and phrases.
[16] Particular embodiments of the present disclosure are described herein below with reference to the accompanying drawings; however, it is to be understood that the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structures.
[17] In accordance with the present disclosure, a cerebral protection system is disclosed. The cerebral protection system of the present invention is inserted with an prosthetic device, say a heart valve using a trans-aortic catheter. The cerebral protection system and the prosthetic device may be introduced inside a human body via a single puncture and/or using a single sheath. The single puncture reduces chances of infection, blood loss, local vascular injury etc. in the patient.
[18] The cerebral protection system is positioned before sub-arteries of aorta, more specifically, the brachiocephalic artery. The deployment of the cerebral protection system at such a position results in coverage of all the sub-arteries of the aorta thereby, eliminating any chance of a stroke.
[19] Further, the cerebral protection system may be employed to capture the emboli post implantation of the artificial heart valve.
[20] In various embodiments, the cerebral protection system is used in association with the TAVR procedure.
[21] The cerebral protection system of the present invention is equipped with filtering and capturing capabilities i.e. first the cerebral protection system filters the bloodstream and then the system captures emboli of a predefined size. The emboli may include thrombus, calcified particles, atheroma, debris, etc. In an embodiment, the cerebral protection system filters and captures emboli of size in a range of 50µm to 200µm to occlude the blood vessels of the brain or other vital organs, thereby providing protection against a silent stroke.
[22] In an embodiment, the cerebral protection system includes a mesh which may be opened and closed in order to capture the emboli. The said opening and closure of the mesh is mediated by a plurality of threads as described in detail below. The threads may be controlled by a roller switch. Such an arrangement reduces any chance of release of the captured emboli from the cerebral protection system back into the arteries during the retrieval of the cerebral protection system.
[23] Now referring specifically to diagrams, FIG. 1 represents a cross-sectional view of a cerebral protection system 100. The cerebral protection system 100 may be introduced into a human body through a trans-femoral approach. In an embodiment, the cerebral protection system 100 is introduced via a trans-aortic approach by advancing the system 100 through a descending aorta into an aortic arch. In an alternate embodiment, the cerebral protection system 100 is introduced via a trans-apical approach.
[24] The cerebral protection system 100 includes a trans aortic catheter 200, an inner tube 102, a mesh 104, an outer sheath 106 and a handle 108.
[25] In an embodiment, the trans aortic catheter 200 is an innermost component of the cerebral protection system 100. The trans aortic catheter 200 may be provided inside the inner tube 102. The trans aortic catheter 200 may be used to deploy a heart valve 202. In an embodiment, the trans aortic catheter 200 includes a proximal end 201a and a distal end 201b. The trans aortic catheter 200 may include a balloon 204 towards the distal end 201b. The heart valve 202 may be balloon-expandable or self-expandable. As per the illustrated embodiment of FIG. 1, the heart valve 202 is mounted over the balloon 204 of the trans aortic catheter 200 for its expansion at a treatment site.
[26] In an embodiment, the inner tube 102 is provided over the trans aortic catheter 220. The inner tube 102 may be a static component of the cerebral protection system 100.The inner tube 102 may include a predefined length. The length of the inner tube 102 may be in a range of 70cm to 180cm. In an embodiment, the length of the inner tube 102 is in a range of 100cm to 130cm. Likewise, the inner tube 102 may include an inner diameter in a range of 10 Fr to 22 Fr, preferably ranging from 12 Fr to 18 Fr and more preferably ranging from 14 Fr to 16 Fr. In an embodiment, the inner diameter of the inner tube 102 is 14 Fr to 16 Fr. The inner tube 102 may include a wall thickness in a range of 50µm to 500µm. In an embodiment, the wall thickness of the inner tube 102 is range from 120µm to 250µm. Hence, owing to the wall thickness of the inner tube 102, an outer diameter of the inner tube 102 may range between 18 Fr to 22 Fr. In an embodiment, the outer diameter of the inner tube 102 is range from 16 Fr to 18 Fr.
[27] The inner tube 102 may be made of a biodegradable polymer material having properties such as elasticity, biocompatibility, flexibility and rigidity in compliance with clinical requirements. The polymer material may include without limitation polytetrafluoroethylene (PTFE), low-density polyethylene (LDPE), high-density polyethylene (HDPE), pebax, polyether ether ketone (PEEK), etc. In an embodiment, the inner tube 102 is made of PTFE.
[28] The inner tube 102 of the cerebral protection system 100 includes a proximal end (not shown) and a distal end 102a. The proximal end may be attached to the handle 108 of the cerebral protection system 100. The proximal end of the inner tube 102 may be affixed with handle 108 by means of glue, UV bonding or adhesive bonding. The mesh 104 may be mounted over the inner tube 102 towards its distal end 102a.
[29] The mesh 104 of the cerebral protection system 100 acts as a blood filter and an emboli collector during the TAVR procedure. In the present invention, the mesh 104 is deployed at a position within the aorta in a way (as shown in fig. 2) such that the mesh 104 covers all sub-arteries of the aorta. Aortic arch has three sub-branches; brachiocephalic artery, left common carotid artery and left subclavian artery which provide blood to different body parts. In an embodiment, the mesh 104 is opened before brachiocephalic artery. Such a positioning renders efficient collection of emboli and prevents heart stroke due to the emboli.
[30] The mesh 104 may be permanently/temporarily attached to the inner tube 102. The mesh 104 may be attached by means of without limitation adhesive bonding, welding or crimping, etc. In an embodiment, the mesh 104 is attached by means of crimping. The mesh 104 may be attached towards the distal end 102a of the inner tube 102. In an embodiment, a marker (not shown) is crimped with the mesh 104 on the distal end 102a of the inner tube 102. The marker may be of any predefined shape. The shape of the marker may include without limitation square, rectangular, oval, triangular, etc. shapes. In an embodiment, a C shaped marker is used. The marker may be made of any fluoroscopic material. The fluoroscopic material may include without limitation platinum, gold, stainless steel, titanium, tantalum or combination thereof. In an embodiment, the marker is made of stainless steel.
[31] The aforesaid attachment of the mesh 104 with the inner tube 102 imparts sufficient strength to the cerebral protection system 100 and helps in eliminating any chances of loosening of the mesh 104 during emboli entrapment.
[32] The mesh 104 may be made of biocompatible materials which may include polymer or metals. The biocompatible materials may include without limitation, nitinol, stainless steel, aluminum, cobalt chromium polyester, polyethylene, etc. In an embodiment, nitinol is used for fabricating the mesh 104. The mesh 104 made of nitinol is biocompatible, kink resistant, elastic, corrosion resistant and has excellent shape memory.
[33] The mesh 104 may be prepared by any efficient technique known in the art for example, laser cutting or braiding. In an embodiment, the mesh 104 is prepared by braiding technique. In braiding technique, approximately 6 to 80 nitinol wires, preferably 20 to 60, and more preferably 30 to 42 nitinol wires may be used for fabricating the mesh 104. In an embodiment, 32 to 40 nitinol wires are used for braiding of the mesh 104. The diameter of the nitinol wires may range from 20 µm to 400 µm. In an embodiment, the diameter of the nitinol wire used for braiding of the mesh 104 is in a range of 120µ to 170µ. The utilization of nitinol wires of aforesaid number and diameter for fabrication of the mesh 104 imparts superior radial support and structural stability.
[34] Braiding of the wires is carried out using a braiding machine. During the braiding process, parameters such as number of carriers, wire diameter, numbers of wires, number of holes on a mandrel, braiding angle, braiding height are considered for obtaining a mesh with desired design, porosity and strength. In an embodiment, the braiding angle largely affects the porosity of the mesh 104. The porosity of the mesh 104 is a critical parameter for efficient filtering and/or collection of the emboli present in a blood stream. The braiding angle for fabrication of the mesh 104 may range between 50° to 140°. In an embodiment, the braiding angle is 90° to 110°. Further, the braiding height may play a significant role in achieving desired braiding angle. The braiding height may refer to a position on the mandrel where the wires interlace into a braid. In an embodiment, the braiding height ranges from 30 cm to 90 cm.
[35] Owing to the aforesaid braiding angle, the pore size of the mesh 104 may lie between 10µm to 400µm. In an exemplary embodiment, the pore size of the mesh 104 is 100µm to 150µm. The pore size of the mesh 104 may be optimized depending upon the size of the emboli which are required to be filtered and/or captured in the mesh 104. In an embodiment, the mesh 104 of the present invention entraps the emboli of size 40 microns and above.
[36] The mesh 104 may be manufactured in any shape depending upon the requirement of treatment. The shape may depend upon the anatomy of the application site and intended use, for example, the conical shaped mesh may be used for filtering and capturing particles in a circular anatomy (lumen) while a tabular shaped mesh may be used for deflection of the blood flow in the circular anatomy (lumen). The shape of the mesh may include without limitation tubular, flat, conical, etc. shapes. In an embodiment, the shape of the mesh 104 is conical as shown in fig. 1 when in open state. The length of the mesh 104 may range from 30 mm to 170 mm. In an embodiment, the length of the mesh 104 is 90mm.
[37] In an embodiment, the mesh 104 includes a proximal end 104a and a distal end 104b. The proximal end 104a of the mesh 104 may be a static end. On the contrary, the distal end 104b of the mesh 104 is a dynamic end and has the capability to open and close. In an embodiment, the distal end 104b of the mesh 104 is provided with a marker (not shown) for better radiopacity and/or accurate positioning of the mesh 104.
[38] The mesh 104 may alternate between an open state and a closed state. In the open state, the distal end 104b of the mesh 104 is flared. The diameter of the distal end 104b in the open state may range from 20 mm to 40 mm. In an embodiment, the diameter of the distal end 104b in the open state is 30mm. In an embodiment, the diameter of the mesh 111 in the closed state is in a range of 4.5 mm to 5.5 mm. On the contrary, in the closed state, the distal end 104b of the mesh 104 remains in compressed/constricted state. The diameter of the distal end 104b in the closed state ranges from 1 mm to 7 mm. In an embodiment, the diameter of the distal end 104b in the closed state is range from 4.5 mm to 5.3 mm.
[39] The switching of the mesh 104 from the open state to the closed state (or vice versa) is mediated by the handle 108 via a plurality of secondary threads and a primary thread. (further elaborated in FIG. 4).
[40] The outer sheath 106 of the cerebral protection system 100 is a tube like structure with a predefined length. The length of the outer sheath 106 may be in a range of 50 cm to 140 cm. In an embodiment, the length of the outer sheath 106 is 80 cm to 120 cm. The diameter of the outer sheath 106 may be in a range of 10 Fr to 30 Fr. In an embodiment, the diameter of the outer sheath 115 is 16 Fr to 24 Fr.
[41] An inner diameter of the outer sheath 115 ranges from 12 Fr to 22 Fr. In an embodiment, the inner diameter of the outer sheath 106 is 16 Fr to 18 Fr. The outer sheath 106 may have a thickness in a range of 50 µm to 500µm. In an embodiment, the thickness of the outer sheath 117 is 100µm to 250µm.
[42] The outer sheath 106 may be made of a biodegradable polymer material having properties such as elasticity, biocompatible, adequate flexibility and enough rigidity to meet the clinical requirement. The polymer material may include without limitation polytetrafluoroethylene (PTFE), low-density polyethylene (LDPE), high-density polyethylene (HDPE), pebax, polyether ether ketone (PEEK), etc. In an embodiment, the outer sheath 106 is made of pebax. The outer sheath 106 is kink resistant, smooth and flexible. The outer sheath 106 may act as a holder to keep the mesh 104 in a compressed state during insertion of the cerebral protection system 100 in a body lumen.
[43] The outer sheath 106 includes a proximal end 106a, a distal end 106b and a lumen (not shown). The lumen of the outer sheath 106 provides a passage for components like the inner tube 102 of the cerebral protection system 100. In an embodiment, the outer sheath 106 is disposed over the inner tube 102 and is slidably coupled to the inner tube 102.
[44] The handle 108 is disposed at the proximal end 106a of the outer sheath 106 and the proximal end of the inner tube 102. The handle 108 acts as a holding means for the cerebral protection system 100. Further, the handle 108 includes few components which regulate/control the expansion/contraction and transition of the mesh 104 from the open state to the closed state. The handle 108 may be made of any durable material known in the art, such as a thermoplastic polymer such as Acrylonitrile butadiene styrene (ABS), Polycarbonate, poly vinyl, etc.
[45] The handle 108 of the cerebral protection system 100 includes a proximal end 108a and a distal end 108b. The distal end 108b of the handle 108 includes a slot 110. The slot 110 extends for a predefined length from the distal end 108b towards the proximal end 108a of the handle 108. The slot 110 may be operatively coupled to a pusher switch 110a. In an embodiment, the pusher switch 110a may be slidably coupled with the slot 110 to facilitate the movement of the outer sheath 106. In an embodiment, the pusher switch 110a is equipped to slide within the slot 110 from a point A to point B (and vice versa). Sliding the pusher switch 110a from point A to point B causes backward movement of the outer sheath 106. Forward movement of the outer sheath 106 is caused by sliding of the pusher switch 110a from the point B to point A. It should be noted that the movement of the outer sheath 106 in the present invention is always with respect to the inner tube 102.
[46] The handle 108 may also include a switch, for example, a roller switch 112. In an embodiment, the switch 112 is disposed adjacent to the pusher switch 110a, near point A of the slot 110. The switch 112 may be a knob-type structure which is configured to rotate either clockwise or anti-clockwise by manual intervention. The switch 112 may be used to regulate opening and closing of the mesh 104.
[47] The switch 112 includes a shaft (not shown) which may be placed inside the handle. The shaft may be wrapped with a primary thread. The clockwise/anti-clockwise rotation of the switch 112 results in forward/backward movement of the primary thread. In an embodiment, the switch 112 is rotated in an anti-clockwise direction to cause forward movement of the primary thread in order to open the mesh 104 for entrapment of the emboli. In another embodiment, the switch 112 is rotated in the clock-wise direction to cause backward movement of the primary thread in order to close the mesh 104 post entrapment of the emboli.
[48] In an embodiment, the primary thread is disposed within the lumen of the inner tube 102. The primary thread may be made of but not limited to polyester, nylon, PLGA monofilament, PDO monofilament, etc. In an embodiment, the primary thread is made of nylon. The diameter of the primary thread ranges from 50 microns to 400 microns. In an embodiment, the diameter of the primary thread is 120 to 180 microns.
[49] FIG. 4 represents the structural arrangement in the cerebral protection system 100 for the opening and closing the mesh 104. In an embodiment, as represented in FIG. 4, the distal end 104b of the mesh 104 is knotted with a plurality of secondary threads 114 throughout its circumference. The plurality of secondary threads may include 2-12 threads. In an embodiment, the cerebral protection device 100 includes 3 to 6 secondary threads. The secondary threads 114 may be knotted at predefined positions on the circumference of the distal end 104b of the mesh 104. In an embodiment, the secondary threads 114 may be equidistantly spaced to form a web like structure.
[50] Each secondary thread 114 includes two ends i.e a first end and a second end. The first end of each secondary thread 114 is knotted to a nitinol wire of the distal end 104b of the mesh 104. The second end of each of the secondary threads 114 is knotted together and subsequently, knotted to the primary thread.
[51] As elaborated above, the clockwise/anti-clockwise rotation of the switch 112 results in forward/backward movement of the primary thread. Hence, on forward movement of the primary thread, the secondary threads 114 loosen to allow opening of the mesh 104 to yield a flared distal end 104b of the mesh 104. On the contrary, backward movement of the primary thread generates a force on the secondary threads 114 which causes retrieval of the secondary threads 114 within the lumen of the inner tube 102 to cause closure of the mesh 104.
[52] The secondary threads 114 may be made of but not limited to PLGA, PLA, PDS, Vicryl, Silk, or any elastic material thread. In an embodiment, the threads 114 are made of nylon. The secondary threads 114 have a smooth surface and are elastic and non-breakable. The diameter of the threads 119 may be in a range of 50µm to 200µm. In an embodiment, the diameter of the threads 119 is in a range of 120µm to 180µm.
[53] Fig. 5 illustrates a flow chart that represents an exemplary process of operating the cerebral protection system 100.
[54] At step 501, the cerebral protection system 100 of the present invention is introduced in the human body through a single introducer sheath. The diameter of the introducer sheath may be in a range of 18 Fr to 26 Fr. In an embodiment, the diameter of the introducer sheath is range from 20 Fr to 24 Fr. The usage of the single introducer sheath leads to a single puncture in a patient’s body. Additionally, the usage of the single introducer sheath reduces the learning curve for the physician, other procedural complexities and provides an additional route in case of emergency or other lethal consequences.
[55] At step 503, the cerebral protection system 100 is advanced through the human body to reach the treatment site. The heart valve 202 is then positioned at the treatment site i.e the aorta.
[56] At step 505, the outer sheath 106 is pulled backwards towards the handle 108. The backward movement of the outer sheath 106 may be accomplished via the pusher switch 110a. The pusher switch 110a is manually slid from the point A to the point B of the slot 110. The displacement of the outer sheath 106 leads to the expansion of the mesh 104 (shown in Fig. 6a).
[57] At step 507, the distal end 104b of the mesh 104 is opened (shown in Fig. 6b). In an embodiment, the opening of the mesh 104 is caused by rotating the switch in the anti-clockwise direction. The mesh 104 is positioned, expanded and opened in such a way that the mesh 104 covers all the sub-arteries of the aorta thereby preventing any chance of stroke.
[58] At step 509, the heart valve 202 is expanded for its implantation within the heart by operation of the trans-aortic catheter 200. The heart valve 202 is expanded by inflating the balloon 204 via saline or air (or any conventional means). The implantation of the heart valve 202 causes release of the emboli/debris.
[59] At step 511, the bloodstream passing through the expanded mesh 104 is filtered and the emboli/debris is captured within the mesh 104.
[60] At step 513, post capture of the emboli/debris, the mesh 104 of the cerebral protection system 100 is closed. The closing of the mesh 104 via secondary threads 114 prevents any chance of slippage of the trapped emboli/debris back into the arteries. Hence, the said arrangement for closure of the mesh 104 helps in effective entrapment of the calcified particles.
[61] At step 515, the outer sheath 106 is pushed towards the distal end 104b of the mesh 104 via sliding the pusher switch 110a from the proximal end A to the distal end B of the slot 110. Due to the forward movement of the outer sheath 106, the mesh 104 is compressed and the cerebral protection system 100 is withdrawn from the body.
[62] The scope of the invention is only limited by the appended patent claims. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings of the present invention is/are used.