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:
PARK ASSIST SYSTEM

2. APPLICANT:
Meril Corporation (I) Private Limited, an Indian company of the address Survey No. 135/139, Muktanand Marg, Bilakhia House, Pardi, Vapi, Valsad-396191 Gujarat, India.

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

FIELD OF INVENTION
[1] This invention relates to a delivery device accessory, in particular, the present disclosure relates to an attachment externally fixed on to a catheter shaft which assists an operator in precise positioning of the distal end/portion of the catheter shaft.
BACKGROUND OF INVENTION
[2] A catheter, for example, a delivery device, is a tubular medical device for insertion in a body lumen such as vessels, passageways, vasculatures, canals etc. and/or cavities for various purposes such as diagnostic, therapeutic etc. In addition, a catheter is used for implanting a device for example, a radially collapsible and expandable device, in a body lumen percutaneously. The device may be, for example, a stent (coronary, peripheral, neurovascular, venous etc.), a graft, a structural heart implant, a prosthetic valve or any other such device.
[3] In some cases, a balloon is attached to the distal end of a catheter which may be inserted in the body lumen and navigated to a treatment site. At the treatment site, the balloon may be inflated to press against a diseased lumen to achieve desired clinical results. The balloon may have a coating on its external surface which may be a therapeutic agent. In some cases, the balloon may have a modified external surface. An implantable medical device may be mounted on the external surface of the balloon in a radially collapsed condition. The balloon may be used for varied treatments.
[4] Typically, a catheter has, for example, one or more concentrically arranged shafts/lumens. The device to be implanted, is carried in a radially collapsed condition on one of the shafts of the catheter normally, towards the distal end. The shaft, along with the radially collapsed device, is inserted into the body lumen of a patient through a puncture. For example, a coronary stent or an aortic prosthetic valve may be introduced through a puncture in femoral artery, known as trans-femoral route. The operator then pushes the shaft of the catheter manually though the vasculature of the patient. The shaft has adequate length such that the radially collapsed device can reach the target site where it is to be implanted. After reaching the target site, the device is radially expanded and is thus implanted at the target site.
[5] To a medical practitioner, it is well-known that the distal end of the catheter should be placed precisely at the target treatment site within the body lumen for achieving various clinical purposes such as diagnosis, therapeutic treatment, accurate placement and subsequent deployment of an interventional device, etc. For example, an interventional device mounted in radially collapsed condition on the catheter, should be implanted at an optimal location to ensure its optimal performance. For example, a coronary, peripheral, neurovascular, venous stent should be implanted in such a manner that it covers the lesion in the body lumen adequately and it extends equally on either side of the lesion. Similarly, in case of a prosthetic valve, the implant must be positioned and deployed with accuracy at the desired anatomical location to avoid iatrogenic damage to its surrounding anatomy. Similarly, in case of a therapeutic treatment such as drug delivery, the distal end of the catheter should reach the precise location where the drug is to be delivered. The aforesaid have been included as exemplary applications of a catheter.
[6] However, the accurate placement of such devices is often a challenge. The implantation procedure is controlled manually by a medical practitioner (also referred to as an operator) who monitors it via fluoroscopy or equivalent imaging procedure. The operator attempts to push the radially collapsed device mounted on the delivery catheter, to the target implantation site. Complications arise as the medical practitioner moves the catheter shaft in forward and backward directions manually to position the device accurately using fluoroscopy or equivalent imaging procedure.
[7] There is thus a need to devise a system that can be used in conjunction with a catheter e.g. a delivery device and can help a medical practitioner to position the catheter e.g. delivery device precisely.
SUMMARY OF INVENTION
[8] 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 mere 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 structure.
[9] The present disclosure relates to a park assist system (PAS) that may be used along with a catheter e.g. a delivery device, used in an interventional procedure wherein the catheter needs to be placed with high precision. In an embodiment, the PAS is an attachment externally fixed on to the catheter. That is, the PAS remains outside the body of the patient and assists the operator in precise positioning of the distal end/portion of the catheter. It may be noted that a “catheter” includes a “delivery device”.
[10] The PAS also facilitates access to the target site for diagnosis, therapeutic treatment, accurate placement and subsequent deployment of the interventional device etc. In addition, PAS of the instant disclosure is of versatile nature such that it can be attached to any such catheter where precise positioning of the catheter shaft is required.
[11] It is important to note that PAS can be used with any and every catheter which are used to conduct various functions/treatments (such as diagnostic, therapeutic etc.), or implant a medical device etc., via a medical procedure. The medical procedures include without limitation, clinical and procedural indications such as:
1. Percutaneous Coronary Interventions (PCI) – angioplasty and stenting of coronary arteries
a. Left main stenting
b. Bifurcation stenting
c. Aorto ostial stenting
d. Simple and Complex PCI
e. Overlapping multiple stenting
f. In-stent restenosis
g. Angioplasty using PTCA balloons
h. Drug Coated Balloon treatment
i. Plaque modification balloons such as cutting or scoring balloons of lesion
j. Intravascular lithotripsy balloon catheter
k. Placement of embolic protection devices
2. Peripheral Vascular Interventions (venous and arterial)
a. Stent graft placement in aortic aneurysms – AAA / TAA
b. Stent placement in peripheral vessels
c. Balloon angioplasty in peripheral vessels
d. Drug coated balloon treatment
e. Stent graft placement
f. Cutting and scoring balloon
g. Intravascular lithotripsy balloon catheter
h. Placement of embolic protection devices
3. Imaging of peripheral, neuro, coronary circulation using IVUS or OCT catheters
4. Interventional Neurovascular procedures
a. Intracranial coiling of aneurysms
b. Stent assisted coiling
c. Placement of catheters in arteriovenous malformations
d. Clot retrival
e. Placement of embolic protection devices
f. Flow diverter stent placement
5. Structural Heart interventional procedures
a. TAVI / TAVR
b. Mitral valve repair and replacement
c. Left Atrial Appendage closure
d. Annuloplasty
e. Balloon valvuloplasty
f. Atrial septostomy
g. Tricuspid valve repair and replacement
h. Transcatheter edge to edge repair
i. Pulmonary valve repair and replacement
j. Congenital heart defect treatment in pediatric and adults – ASD, mVSD, PFO, PDA
[12] It is to be noted that the aforesaid procedures are merely examples of the procedures where PAS of the instant disclosure can be used. PAS of the instant invention can be attached to any catheter where precise positioning of the catheter shaft is needed.
[13] The PAS of present disclosure allows the operator to move the shaft of the catheter in a controlled manner by which positioning the shaft of the catheter at the exact target site becomes easy and accurate.
[14] In an embodiment, the present disclosure relates to a park assist system provided on a catheter shaft. The park assist system includes a slider shaft, an inner shaft and a roller. The slider shaft is fixed rigidly onto an outer surface of a catheter shaft. The inner shaft is operatively coupled to the slider shaft. The roller is operatively coupled to a distal portion of the inner shaft. The roller upon rotation, is configured to control a translational motion to the slider shaft via the inner shaft, thereby positioning a distal end of the catheter shaft accurately at a treatment site.
[15] In another embodiment, the present disclosure relates to a park assist system provided on a catheter shaft. The park assist system includes a slider shaft, and a slider projection. The slider shaft is fixed rigidly onto an outer surface of a catheter shaft. The slider projection is fixed onto the slider shaft to control a translational motion to the slider shaft, the slider projection being configured to move in a proximal or a distal direction at a time. The length of the translational motion of the slider shaft, defines extent of axial movement of the catheter shaft in the direction of motion of the slider shaft, thereby accurately positioning a distal end of the catheter shaft at a treatment site.
[16] In another embodiment, the present disclosure relates to a method to control a position of a distal end of a catheter shaft using a park assist device. The method commences by fixing a slider shaft onto an outer surface of a catheter shaft. A rotational motion is imparted to a roller coupled to a distal portion of an inner shaft. The inner shaft is operatively coupled to the slider shaft. A translational motion of the slider shaft is controlled via the inner shaft. The translational motion of the slider shaft corresponds to the rotational motion of the roller. A translational motion of the catheter shaft is controller to control a position of the distal end of the catheter shaft. The translational motion of the catheter shaft corresponds to the rotational motion of the roller.
[17] In another embodiment, the present disclosure relates to a method to control a position of a distal end of a catheter shaft using a park assist device. The method commences by fixing a slider shaft onto an outer surface of a catheter shaft. A translational motion is imparted to a slider projection in a proximal or a distal direction at a time. The slider projection is coupled to the slider shaft. A translational motion of the slider shaft is controlled. The translational motion of the slider shaft corresponds to the translational motion of the slider projection. An axial movement of the catheter shaft is controlled in the direction of the translational motion of the slider projection to control a position of the distal end of the catheter shaft. The extent of axial movement of the catheter shaft corresponds to the length of the translational motion of the slider projection.
BRIEF DESCRIPTION OF DRAWINGS
[18] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the apportioned 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 instrumentality disclosed herein. Moreover, those in the art will understand that the drawings are not to scale.
[19] Fig. 1 depicts a park assist system (or PAS) 100 according to an embodiment of the present disclosure.
[20] Fig. 1a depicts a cross-sectional view of the PAS 100 according to an embodiment of the present disclosure.
[21] Fig. 1b depicts an exploded view of the PAS 100 according to an embodiment of the present disclosure.
[22] Fig. 2 depicts a handle 110 of the PAS 100 according to an embodiment of the present disclosure.
[23] Fig. 2a depicts an upper part 110a and a lower part 110b of the handle 110 of the PAS 100 according to an embodiment of the present disclosure.
[24] Fig. 3 depicts a roller 120 of the PAS 100 according to an embodiment of the present disclosure.
[25] Fig. 3a depicts a proximal view of the roller 120 of the PAS 100 according to an embodiment of the present disclosure.
[26] Fig. 4 depicts an end cap 130 of the PAS 100 according to an embodiment of the present disclosure.
[27] Fig. 4a depicts a cross-sectional view of the end cap 130 of the PAS 100 according to an embodiment of the present disclosure.
[28] Fig. 5 depicts an inner shaft 140 of the PAS 100 according to an embodiment of the present disclosure.
[29] Fig. 5a depicts a cross-sectional view of the inner shaft 140 of the PAS 100 according to an embodiment of the present disclosure.
[30] Fig. 6 depicts a slider shaft 150 of the PAS 100 according to an embodiment of the present disclosure.
[31] Fig. 6a depicts a cross-sectional view of the slider shaft 150 of the PAS 100 according to an embodiment of the present disclosure.
[32] Fig. 6b depicts a proximal view of the slider shaft 150 of the PAS 100 according to an embodiment of the present disclosure.
[33] Fig. 7 depicts a cross-sectional view of a locking ring 160 of the PAS 100 according to an embodiment of the present disclosure.
[34] Fig. 8 depicts a locking nut 170 of the PAS 100 according to an embodiment of the present disclosure.
[35] Fig. 8a depicts a perspective view of the locking nut 170 of the PAS 100 according to an embodiment of the present disclosure.
[36] Fig. 9 depicts a marking 11 on a catheter shaft 10 coupled to the PAS 100 according to an embodiment of the present disclosure.
[37] Fig. 9a depicts the marking 11 on the catheter shaft 10 once the shaft is moved according to an embodiment of the present disclosure.
[38] Fig. 10a depicts a window 110c on the handle 110 of the PAS 100 according to an embodiment of the present disclosure.
[39] Fig. 10b depicts scale markings 110d on the catheter shaft 10 coupled to the PAS 100 according to an embodiment of the present disclosure.
[40] Fig. 11A depicts a flowchart of a method 1100 of assembling the catheter shaft 10 and the PAS 100 according to an exemplary embodiment of the present disclosure.
[41] Fig. 11B depicts a flowchart of a method 1200 of operation of the PAS 100 according to an exemplary embodiment of the present disclosure.
[42] Fig. 12 depicts PAS 200 with a slider projection 280 according to an embodiment of the present disclosure.
[43] Fig. 12a depicts a cross-sectional view of PAS 200 with the slider projection 280 according to an embodiment of the present disclosure.
[44] Fig. 12b depicts the slot 213 on the handle 210 of PAS 200 according to an embodiment of the present disclosure.
[45] Fig. 12c depicts an exploded view of the PAS 200 according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF ACCOMPANYING DRAWINGS
[46] 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, coupled 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.
[47] Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment, but mean “one or more but not all embodiments” unless expressly specified otherwise. The terms “including,” “comprising,” “having,” and variations thereof mean “including but not limited to” unless expressly specified otherwise. An enumerated listing of items does not imply that any or all of the items are mutually exclusive and/or mutually inclusive, unless expressly specified otherwise. The terms “a,” “an,” and “the” also refer to “one or more” unless expressly specified otherwise.
[48] Although the operations of exemplary embodiments of the disclosed method may be described in a particular, sequential order for convenient presentation, it should be understood that the disclosed embodiments can encompass an order of operations other than the particular, sequential order disclosed. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Further, descriptions and disclosures provided in association with one particular embodiment are not limited to that embodiment, and may be applied to any embodiment disclosed herein. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed system, method, and apparatus can be used in combination with other systems, methods, and apparatuses.
[49] Furthermore, the described features, advantages, and characteristics of the embodiments may be combined in any suitable manner. One skilled in the relevant art will recognize that the embodiments may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments. These features and advantages of the embodiments will become more fully apparent from the following description and apportioned claims, or may be learned by the practice of embodiments as set forth hereinafter.
[50] The present disclosure discloses a park assist system (or PAS). The PAS is used to provide fine control over advancement/retraction of a catheter (for example, a delivery catheter) within a patient’s vasculature. In an embodiment, the PAS is an attachment externally fixed on to the catheter system which assists the operator in precise positioning of the distal end/portion of the catheter with ease and thus also facilitates reaching the target site for diagnosis, therapeutic treatment, accurate placement and subsequent deployment of the interventional device etc. Reaching exact implantation site is not easy as the operator has to move the catheter shaft in forward and backward directions to position the device accurately using fluoroscopy or equivalent imaging procedure. The PAS of this invention allows the operator to move the shaft of the catheter in a controlled manner by which positioning the device at the exact target site becomes easy and quite accurate. In addition, the PAS of the present disclosure is of versatile nature such that it can be attached to any such catheter where precise positioning of its distal end/portion is required.
[51] In this description, the proximal side/end of the catheter, PAS or any of its components refers to the side/end towards the operator and the distal side/end refers to the side/end away from the operator. The proximal end/side of the individual parts in the description is denoted as P while the distal end/side of the individual parts is denoted as D.
[52] In an embodiment where the translational movement of a catheter shaft is achieved by a controlled rotational movement, the catheter shaft is locked with a slider shaft having external threads which mate with the threads provided on the inner surface of an inner shaft to which a roller is attached at the distal end. The catheter shaft passes through the PAS of the present disclosure such that the shaft can slide through the roller and the inner shaft but is locked with the slider shaft. Rotating the roller rotates the first shaft which moves the slider shaft axially. As the slider shaft is locked with the catheter shaft, the catheter shaft (and hence the catheter as a whole) moves axially with the second shaft.
[53] In another embodiment where the translational movement of a catheter shaft is to be achieved by a controlled sliding motion, the catheter shaft is locked with a slider shaft which the operator can slide in a controlled manner. A holder (or slider) is provided on the slider shaft that protrudes out from the PAS which the operator may manipulate to achieve the translational motion.
[54] In an exemplary procedure, the operator pushes the distal end of the catheter inside a body lumen till it is in the vicinity of the target treatment site within the vasculature of the patient, under guidance of fluoroscopy or equivalent imaging procedure. The operator is then required to adjust the distal end/portion of the catheter in a controlled manner so as to reach the treatment site with precision. The PAS of the present disclosure helps the operator in this task. The rotation of the roller or sliding handle on PAS imparts axial movement to the entire catheter. Rotating the roller in one direction moves the catheter in for example, a forward direction; while rotating the roller in the opposite direction moves the catheter in for example, a backward direction. Further, due to controlled rotation of the roller, the axial movement of the catheter is also controlled. Alternately, the operator may use the sliding motion to move the catheter back and forth in a controlled manner. The operator can control the speed and the extent of the translational movement of the catheter by controlling the speed of rotation of the roller or the sliding movement. In this manner, the operator can precisely position the distal end/portion of the catheter with ease using the PAS of the present disclosure.
[55] Now referring to the figures, Fig. 1 depicts an exemplary embodiment of a PAS 100 operationally coupled to an exemplary catheter shaft 10 (for example, a delivery catheter). In an exemplary embodiment, the PAS 100 is coupled to a proximal portion of the catheter shaft 10 such that the PAS 100 remains outside a human body during medical procedures. The diameter of the catheter shaft 10 on which the PAS 100 is to be attached, is complementary to the lumen of the PAS 100. That is, the PAS 100 is required to be sized for the catheter shaft 10 on which it is intended to be used.
[56] The extent of the controlled axial movement of the catheter shaft 10 may be different depending on its function. Hence, the overall length of the PAS 100 may vary depending upon the function/requirement, the convenience of the medical practitioner and the requirements of the procedure for which the catheter is used, etc. Hence, the overall length of the PAS 100 may be selected keeping in mind all these requirements for a specific catheter shaft 10. The overall length of the PAS 100 is the length defined between its proximal end P and the distal end D.
[57] Fig. 1a depicts a cross-sectional view of the PAS 100 with a catheter shaft 10 and Fig. 1b depicts an exploded view of the PAS 100 without the catheter shaft 10. The PAS 100 extends between a proximal end P and a distal end D. The PAS 100 includes a plurality of components including, but not limited to, a handle 110, a roller 120, an end cap 130, an inner shaft 140, a slider shaft 150, a locking ring 160, a locking nut 170, etc. operationally coupled as described in the later part of the description.
[58] As depicted in Fig. 1a, the end cap 130 is situated at the proximal end P while the roller 120 is situated at the distal end D. The handle 110 is positioned between the roller 120 and the end cap 130. To a skilled person, it will be apparent that the PAS 100 of the present disclosure can function even when orientation of the PAS 100 is reversed i.e. the roller 120 is positioned at the proximal end P and the end cap 130 is positioned at the distal end D. In an exemplary embodiment, the overall length of the PAS 100 is around 100-110 mm. However, the length of the PAS 100 may be shorter or longer depending on requirements as described later.
[59] In the embodiment described above, the PAS 100 of the present disclosure uses rotational movement of the roller 120 for axially moving the catheter shaft 10. In this embodiment, the catheter shaft 10 is locked with the slider shaft 150 having external threads which mate the internal threads provided on the inner surface of the inner shaft 140 to which the roller 120 is attached at the distal end D. The catheter shaft 10 passes through the PAS 100 of the present disclosure such that the catheter shaft 10 can slide through the roller 120, the end cap 130 and the inner shaft 140 but is locked with the slider shaft 150. Rotating the roller 120 rotates the inner shaft 140 which moves the slider shaft 150 axially. As the slider shaft 150 is locked with the catheter shaft 10, the catheter shaft 10 as a whole, moves axially with the slider shaft 150. In other words, the catheter shaft 10 moves in the direction of the slider shaft 150. Thus, by controlled rotation of the roller 120, a distal end of the catheter shaft 10 is positioned accurately at the treatment site. Rotating the roller 120 in one direction moves the slider shaft 150 and the catheter shaft 10 in, for example, a forward direction. While rotating the roller 120 in the opposite direction moves the slider shaft 150 and the catheter shaft 10 in, for example, a backward direction.
[60] The handle 110 of the PAS 100 is depicted in Fig. 2. The handle 110 extends between the proximal end P and the distal end D of the PAS 100. The handle 110 may be made of any biocompatible polymeric material (for example, polycarbonate, polyethylene, polypropylene etc.), biocompatible metallic material (for example, stainless steel, titanium etc.) or any combination thereof. In an exemplary embodiment, the handle 110 is made from polycarbonate.
[61] In an exemplary embodiment, as shown in Fig. 2, the handle 110 is a hollow cylinder such that it defines a lumen that houses few of the components of the PAS 100. For example, the handle 110 houses the inner shaft 140, the slider shaft 150, the locking ring 160, the locking nut 170, etc.
[62] The distal end D of the handle 110 includes an end portion 111 configured to receive the roller 120 (described later). The proximal end P of the handle 110 is provided at least partially with external threads 113 configured to receive the end cap 130 (described later). Alternate ways of coupling end cap 130 with the proximal end P of the handle 110 are within the teachings of the present disclosure.
[63] As shown in an exemplary depiction of Fig. 1a, an inner surface of the lumen of the handle 110 is provided with at least one annular groove 117 and at least one axially extending groove 119. The annular groove 117 may be disposed towards the distal end D and configured to receive at least a portion e.g. a flanged portion of the inner shaft 140 (described later). The axially extending groove 119 may be disposed towards the proximal end P configured to receive at least a portion of the slider shaft 150 e.g. projections (described later). In an exemplary embodiment, the handle 110 is provided with one annular groove 117 and two axially extending grooves 119.
[64] As depicted in Fig. 2a, the handle 110 may be made of two parts viz. an upper part 110a and a lower part 110b. The upper part 110a and the lower part 110b may be removably coupled via a plurality of interlocking projections 115 and grooves (not shown) provided within the thickness of the handle 110. The upper part 110a and the lower part 110b of the handle 110 help in easy assembly of the PAS 100. Alternately, the handle 110 may be a single integral unit.
[65] Alternately, instead of the interlocking projections 115 and grooves, the upper part 110a and the lower part 110b may be coupled with the help of other functionally equivalent structures/techniques known in the art and the same is within the scope of the teachings of the present disclosure.
[66] Fig. 3 depicts a side view of the roller 120. The roller 120 may be made of any biocompatible polymeric material (for example, polycarbonate, polyethylene, polypropylene etc.), biocompatible metallic material (for example, stainless steel, titanium etc.) or any combination thereof. In an exemplary embodiment, the roller 120 is made from polycarbonate.
[67] In an exemplary embodiment, as shown in Fig. 3, the roller 120 is bullet shaped. However, it may be of any shape convenient for its operation.
[68] The roller 120 defines a first tubular opening 121 disposed at the proximal end P and a second tubular opening 123 disposed towards the distal end D.
[69] Fig. 3a depicts the roller 120 when viewed from the proximal end P. In an exemplary embodiment, as shown in Fig. 3a, the first tubular opening 121 has a larger diameter than the diameter of the second tubular opening 123. The first tubular opening 121 operationally couples the roller 120 to the handle 110. For example, the first tubular opening 121 of the roller 120 is coupled to the end portion 111 of the handle 110 such that the roller 120 is able to rotate freely with respect to the handle 110. In an exemplary embodiment, the first tubular opening 121 of the roller 120 is snap-fitted (or press-fitted) over the end portion 111 of the handle 110 thus, securing the roller 120 to the handle 110 such that the roller 120 is free to rotate relative to the handle 110. The press-fit between the roller 120 and the handle 110 should be tight enough to prevent disengagement of the roller 120 from the handle 110 and still be free enough to allow rotation of the roller 120. To prevent disengagement of the roller 120 from the handle 110, various methods may optionally be used such as, providing one or more projections on the inside of the first tubular opening 121 and corresponding cavities on the surface of the handle 110 where the roller 120 is press-fitted. Any other method known in art may be used for preventing the roller 120 from disengagement from the handle 110.
[70] In place of the snap-fit coupling between the roller 120 and the handle 110, any other functionally equivalent technique known in the art may be used and the same is within the scope of the teachings of the present disclosure.
[71] The roller 120 includes a plurality of pins 123a (hereinafter, pins 123a). Specifically, the pins 123a may be provided around the second tubular opening 123. For example, Fig. 3a shows four pins 123a. The pins 123a may extend towards the proximal end P within the roller 120. The second tubular opening 123 of the roller 120 along with the pins 123a are operationally coupled to a portion of the inner shaft 140 (described later).
[72] As shown in exemplary Fig. 3, an outer surface of the roller 120 may be provided with a plurality of ridges 120a to enable the operator of the PAS 100 to have fine control on the rotation of the roller 120.
[73] Fig. 4 depicts the end cap 130 of the PAS 100. The end cap 130 is secured to the proximal end P of the PAS 100. The end cap 130 may be made of any biocompatible polymeric material (for example, polycarbonate, polyethylene, polypropylene etc.), biocompatible metallic material (for example, stainless steel, titanium etc.) or any combination thereof. In an exemplary embodiment, the end cap 130 is made from polycarbonate.
[74] Fig. 4a depicts a cross-sectional view of the end cap 130. As shown in Fig. 4a, the end cap 130 may define an opening 131 that has a larger diameter on the distal side D and a smaller diameter on the proximal side P. The smaller diameter on the proximal side P is complementary to the diameter of the catheter shaft 10 to enable the catheter shaft 10 to pass through (as shown in Fig. 1a). For example, the smaller diameter on the proximal side 101a may be fractionally more than the diameter of the catheter shaft 10 so that the catheter shaft 10 can easily slide through it. At least a portion of an inner surface of the opening 131 of larger diameter is provided with a plurality of internal threads 131a. In an exemplary embodiment, the plurality of internal threads 131a is provided towards the distal end D of the end cap 130. The plurality of internal threads 131a engages the external threads 113 of the handle 110 to secure the end cap 130 to the proximal end P of the handle 110.
[75] Instead of the internal threads 131a and the external threads 113, other functionally equivalent techniques may be used to couple the end cap 130 to the handle 110 and the same is within the scope of the teachings of the present disclosure.
[76] Fig. 5 depicts the inner shaft 140 of the PAS 100. The inner shaft 140 may be made of any biocompatible polymeric material (for example, polycarbonate, polyethylene, polypropylene etc.), biocompatible metallic material (for example, stainless steel, titanium etc.) or any combination thereof. In an exemplary embodiment, the inner shaft 140 is made from polycarbonate.
[77] In an exemplary embodiment, as shown in Fig. 5, the inner shaft 140 is a hollow cylinder defining a lumen. The inner shaft 140 includes an outer surface and an inner surface.
[78] The outer surface of the inner shaft 140 may be provided with at least two flanged portions. In the exemplary depiction, the outer surface is provided with a first flanged portion 141 and a second flanged portion 143 spaced from each other. The first flanged portion 141 is provided with at least one hole 141a. In an embodiment, the number of holes 141a provided on the first flanged portion 141 is equal to the number of pins 123a provided within the roller 120.
[79] As shown in Fig. 1a, the first flanged portion 141 is disposed within the roller 120 such that the pins 123a are disposed within the hole/s 141a of the first flanged portion 141. The disposition of the pins 123a within the hole/s 141a helps to transfer the rotational motion of the roller 120 to the inner shaft 140. When the roller 120 is rotated, the handle 110 is held stationary but the inner shaft 140 rotates along with the roller 120.
[80] In place of the pins 123a and the holes 141a, other functionally equivalent structures/techniques (for example, adhesive, wires, suturing etc.) may be used to couple the roller 120 with the inner shaft 140 and the same is within the scope of the teachings of the present disclosure.
[81] As shown in Fig. 1a, the second flanged portion 143 is disposed within the groove 117 of the handle 110. The disposition of the second flanged portion 143 within the groove 117 of the handle 110 restricts axial movement of the inner shaft 140 with respect to the handle 110. However, the inner shaft 140 is free to rotate with respect to the handle 110 by mimicking the rotational motion of the roller 120.
[82] The proximal end P of the inner shaft 140 is a free end.
[83] Fig. 5a depicts cross-sectional view of the inner shaft 140. At least a portion of the inner surface of the lumen of the inner shaft 140 is provided with a plurality of internal threads 145 configured to engage with at least a portion of the slider shaft 150 (described later).
[84] The length of the inner shaft 140 may depend upon the desired extent of the movement of the catheter shaft 10 on which PAS 100 is fixed, which in turn depends on the requirements of the medical practitioner/procedure. In an exemplary embodiment, the length of the inner shaft 140 is around 48 mm.
[85] Fig. 6 depicts the slider shaft 150 of the PAS 100. The slider shaft 150 may be made of any biocompatible polymeric material (for example, polycarbonate, polyethylene, polypropylene etc.), biocompatible metallic material (for example, stainless steel, titanium etc.) or any combination thereof. In an exemplary embodiment, the slider shaft 150 is made from polycarbonate.
[86] In an exemplary embodiment, as shown in Fig. 6, the slider shaft 150 is a hollow cylinder defining a lumen L (as shown in Fig. 6a). The lumen L of the slider shaft 150 surrounds the catheter shaft 10 (as shown in Fig. 1a). Hence, the diameter of the lumen L of the slider shaft 150 is based on the outer diameter of the catheter shaft 10 such that the catheter shaft 10 can slide through the lumen L.
[87] At least a first portion of an outer surface of the slider shaft 150 is provided with a plurality of first external threads 151. In an exemplary embodiment, as shown in Fig. 6, the plurality of first external threads 151 is disposed towards the distal end D of the slider shaft 150. The slider shaft 150 is at least partially disposed within the inner shaft 140 (as shown in Fig. 1a) such that the first external threads 151 at least partially engage with the internal threads 145 of the inner shaft 140. The length of the internal threads 145 (on the inner shaft 140) and the length of the first external threads 151 (on the slider shaft 150) set the limit of axial movement of the catheter shaft 10 on which the PAS 100 is coupled. Hence, these lengths may depend upon the desired extent of the movement of the catheter shaft 10 on which PAS 100 is fixed, which in turn depends on the requirements of the medical practitioner/procedure.
[88] At least a second portion of the outer surface of the slider shaft 150 is provided with a plurality of second external threads 153. In an exemplary embodiment, as shown in Fig. 6, the plurality of second external threads 153 is disposed towards the proximal end P of the slider shaft 150. The plurality of second external threads 153 is configured to at least partially receive the locking nut 170 (described later).
[89] The slider shaft 150 is provided with at least one projection 155. The number of projections 155 correspond to the number of axially extending grooves 119 provided within the handle 110. In an exemplary embodiment, as shown in Figs. 6 and 6b, the slider shaft 150 is provided with two projections 155. The projection/s 155 slide/s within the axially extending groove/s 119 of the handle 110 thereby preventing the slider shaft 150 to rotate with respect to the handle 110 and guide the axial movement of the slider shaft 150. In an exemplary embodiment, there are two projections 155 each disposed on either side of the slider shaft 150 to guide the axial movement of the slider shaft 150 within the handle 110 which has corresponding axially extending grooves 119.
[90] At least a portion of the slider shaft 150, defines a cavity 157 (as shown in Fig. 6a) located towards the proximal end P, that may be diametrically larger than the lumen L of the slider shaft 150. The cavity 157 helps to accommodate the locking ring 160 along with the catheter shaft 10 (described later). The second external threads 153 are disposed on this portion as shown in Figs. 6 and 6a.
[91] Fig. 7 depicts a cross-sectional view of the locking ring 160 of the PAS 100. The locking ring 160 is made of an elastomeric material (that can be pressed) such as silicone or any other similar material known in the art. In an exemplary embodiment, the locking ring 160 is cylindrical in shape.
[92] The locking ring 160 may define an internal diameter ‘D1’ and an external diameter ‘D2’. The internal diameter ‘D1’ of the locking ring 160 is either smaller than or equal to the diameter of the catheter shaft 10 on which the PAS 100 is to be coupled. The external diameter ‘D2’ of the locking ring 160 corresponds to the diameter of the cavity 157 of the slider shaft 150.
[93] Fig. 8 depicts the locking nut 170 of the PAS 100. The locking nut 170 may be made of any biocompatible polymeric material (for example, polycarbonate, polyethylene, polypropylene etc.), biocompatible metallic material (for example, stainless steel, titanium etc.) or any combination thereof. In an exemplary embodiment, the locking nut 170 is made from polycarbonate.
[94] Fig. 8a shows perspective view of the locking nut 170. As shown in Fig. 8a, the locking nut 170 includes, without limitation, a cap 171 and a cylindrical portion 173. The cap 171 along with the cylindrical portion 173 defines an annular cavity 157 therebetween.
[95] At least a portion of an inner surface of the cap 171 is provided with a plurality of internal threads 171a. The internal threads 171a of the locking nut 170 engage with the second external threads 153 of the slider shaft 150 to secure the locking nut 170 to the slider shaft 150. The second external threads 153 of the slider shaft 150 are disposed at least partially within the annular cavity 157 of the locking nut 170.
[96] Additionally or optionally, an outer surface of the cap 171 is provided with a plurality of ridges 171b. The plurality of ridges 171b helps the operator of the PAS 100 to easily secure the locking nut 170 on the slider shaft 150 over the second external threads 153 (described later).
[97] The cylindrical portion 173 defines a lumen configured to receive the catheter shaft 10. Hence, the diameter of this lumen is based on the diameter of the catheter shaft 10 such that the catheter shaft 10 can easily slide through this lumen. The cylindrical portion 173 of the locking nut 170 is at least partially disposed within the cavity 157 of the slider shaft 150. The diameter D1 of the opening in the locking ring 160 (Fig. 7), as described above, is preferably sized such that it fits tightly over the outer shaft of the catheter. In the preferred embodiment, the diameter D1 is marginally smaller than the outer diameter of the catheter shaft 10. When the locking nut 170 is tightened over the second external threads 153 of the slider shaft 150, it applies a pressure on the locking ring 160. Due to elastic nature of the locking ring 160, the locking ring 160 presses against the catheter shaft 10 and is rigidly attached to the catheter shaft 10. Hence, the axial movement of the slider shaft 150 is transmitted to the catheter shaft 10 and the catheter moves along with the slider shaft 150 in the axial direction. The coupling of the slider shaft 150 and the catheter shaft 10 in this manner enables the catheter shaft 10 to mimic the linear motion of the slider shaft 150.
[98] The second tubular opening 123 in the roller 120, the lumen of the inner shaft 140, the lumen of the slider shaft 150, lumen 173 in the locking nut 170 and the lumen 131 in the end cap 130 are sized to accommodate the outer shaft of the catheter shaft 10 such that the outer shaft of the catheter shaft 10 can move freely in the axial direction within PAS 100.
[99] In an exemplary embodiment, the working of PAS 100 of the preferred embodiment is now described. Fig. 9 shows the PAS 100 with the slider shaft 150 towards the distal end D. When the roller 120 is rotated in one direction, the handle 110 remains stationary and the inner shaft 140 is rotated in the same direction but does not move axially. The internal threads 145 inside the inner shaft 140, which are engaged with the first external threads 151 of the slider shaft 150, rotate the slider shaft 150. The slider shaft 150 is free to move axially within the inner shaft 140 and the handle 110, hence it moves towards the distal direction along with the locking ring 160 and the locking nut 170. When the roller 120 is rotated in the other direction, the slider shaft 150 moves towards the distal direction along with the locking ring 160 and the locking nut 170.
[100] Fig. 9a shows the PAS 100 with the slider shaft 150 moved to the proximal position. As mentioned above, the axial movement of the slider shaft 150 is transmitted to the catheter shaft 10 and the catheter shaft 10 moves along with the slider shaft 150 in axial direction in a controlled manner. This movement can easily be controlled by the operator.
[101] The relation between the direction of rotation of the roller 120 (clockwise/anticlockwise) and the direction of the axial movement (distal/proximal) of the slider shaft 150 can be arranged in any manner based on the direction of the internal threads 145 and the first external threads 151. For example, in the preferred embodiment of the PAS 100, the slider shaft 150 moves towards the distal direction when the roller 120 is rotated anticlockwise and the slider shaft 150 moves towards the proximal direction when the roller 120 is rotated clockwise.
[102] The limit of this axial movement of the catheter shaft 10 depends on the length of the internal threads 145 of the inner shaft 140 and length of the first external threads 151 of the slider shaft 150 as mentioned earlier. The lengths of the inner shaft 140 and the slider shaft 150 are determined based on the lengths of their respective threads. The length of the handle 110 and the length of the PAS 100 are determined based on lengths of the inner shaft 140, slider shaft 150, the extent of axial movement of the catheter shaft 10 and other components housed within the handle 110.
[103] The extent of the axial movement of the slider shaft 150 depends on the convenience of the operator i.e. how close the operator can push the distal end/portion of the catheter shaft 10 manually to the desired treatment site conveniently. For example, if the extent of the axial movement is 20mm, the operator should manually push the distal end of the catheter shaft 10 within 20 mm of the desired treatment site. Thereafter, the operator rotates the roller 120 in a direction which makes the PAS 100 to move the catheter shaft 10 (and its distal end) towards the desired treatment site. As this movement is controlled by the rotational movement of the roller 120 and the configuration of the internal threads 145 and first external threads 151, the operator can easily move the distal end of the catheter shaft 10 precisely to the desired treatment site under guidance of fluoroscopy or equivalent imaging procedure.
[104] A skilled person may choose the value of the extent of the axial movement of the slider shaft 150 based on her/his knowledge about the comfort level of the operator for specific catheter shaft 10 and treatment requirements. Normally, the extent of axial movement may vary between 15 mm and 30 mm. However, it can be less than 15 mm or more than 30 mm depending on the treatment requirements. The lengths of internal threads 145 and first external threads 151 and the overall dimensions of PAS 100 may be adjusted based on the chosen extent of axial movement of the slider shaft 150.
[105] In an embodiment, indication of the degree (or extent) of linear movement of the catheter shaft 10 via the PAS 100 may be visually indicated to the operator by providing a marking on the catheter shaft 10 at an appropriate location. For example, Figs. 9 and 9a show this marking 11 on the catheter shaft 10. As shown in Fig. 9, where the slider shaft 150 is in the distal position, the marking 11 on the catheter shaft 10 is seen at a distance L1 from the distal end D of PAS 100. When the slider shaft 150 is moved towards the proximal end P as shown in Fig. 9a, the marking 11 on the catheter shaft 10 moves proximally and seen at a distance L2 which is smaller than the distance L1. In this manner, the operator is informed of the movement of the catheter shaft 10. Additional markings with scale (indicia) may be provided to obtain an indication of exact distance the catheter shaft 10 has moved as described later.
[106] In another exemplary embodiment, as shown in Fig. 10a, the handle 110 is provided with a window 110c optionally with a scale 110c1. An indicator 110c2 may be coupled to the slider shaft 150 such that the indicator 110c2 travels along a length of the window 110c as the slider shaft 150 moves axially. Instead of the indicator 110c2, at least one of the projections 155 of the slider shaft 150 which travels along the length of the window 110c, may be used as an indicator of the travel. The position of the indicator 110c2 and/or the projection 155 with respect to the scale 110c1 is indicative of the degree of linear movement of the catheter shaft 10 with respect to the PAS 100.
[107] Additionally or optionally, the indicator 110c2 and/or the projection (s) 155 may be colored for better visibility / easy identification.
[108] In another exemplary embodiment, as shown in Fig. 10b, the catheter shaft 10 is provided with scale markings 110d. As the catheter shaft 10 slides through the PAS 100, the change in the scale reading with respect to the proximal end P of PAS 100 also changes. This change indicates the extent of the axial movement of the catheter shaft 10. A skilled person will realize that the scale markings 110d may alternately be provided on the catheter shaft 10 extending from the distal end D of the PAS 100 which will also indicate the extent of axial movement of the catheter shaft 10 in similar manner.
[109] After the distal end of the catheter shaft 10 is pushed to the precise treatment site within the lumen of the patient’s body, the operator conducts the treatment (such as drug delivery, implantation of a device etc.). During this procedure, the catheter shaft 10 should be held firmly in position so that the distal end of the catheter shaft 10 is maintained at the precise treatment site. A stand may be used to hold the catheter shaft 10 firmly in position. A skilled person is well familiar with such stands and can easily provide one.
[110] A flowchart of an exemplary method 1100 of assembling the catheter shaft 10 and the PAS 100 of the present disclosure is described in Fig. 11A. For illustrating this method, the example of the PAS 100 with the handle 110 in two parts viz. 110a (upper part) and 110b (lower part) is chosen. Fig. 1b shows all the parts of PAS 100 with the handle 110 in two parts viz. 110a and 110b.
[111] In Step 1102, a location is chosen on the proximal portion of the catheter shaft 10 for fixing the PAS 100 such that when PAS 100 is fixed at this location, it will remain outside the body of the patient during the entire procedure and it is convenient for the operator to operate PAS 100 with ease.
[112] In Step 1104, the PAS 100 is disassembled and the catheter shaft 10 is inserted into all the parts (viz. the roller 120, the inner shaft 140, the slider shaft 150, the locking ring 160, the locking nut 170 and the end cap 130) in a sequence as illustrated in Fig. 1b. As the handle 110 is in two parts, it may be fixed later.
[113] In Step 1106, the slider shaft 150 is fixed onto the outer surface of the catheter shaft 10. The slider shaft 150 is fixed by introducing the locking ring 160 in the cavity 157 of the slider shaft 150 and it is pressed by fixing the locking nut 170 on the second external threads 153 on the slider shaft 150 such that the slider shaft 150 is fixed firmly onto the outer surface of the catheter shaft 10 at the chosen location.
[114] In Step 1108, the inner shaft 140 is fixed onto the slider shaft 150 by threading the inner shaft 140 onto the slider shaft 150. To thread the two, mating internal threads 145 of the inner shaft 140 and the first external threads 151 of the slider shaft 150 are used.
[115] In Step 1110, the roller 120 is fixed to the inner shaft 140 with the help of pins 123a in the roller 120 and the holes 141a in the first flanged portion 141 of the inner shaft 140 (or by other methods as described above such as using adhesive, wires, sutures etc.).
[116] In Step 1112, the two parts 110a and 110b of the handle 110 are assembled such that the second flanged portion 143 of the inner shaft 140 is located in the groove 117 in the handle 110 and the roller 120 is fixed onto the distal end of the handle 110 using methods described above (para 68/69).
[117] In Step 1114, the end cap 130 is threaded onto the handle 110 by engaging internal threads 131a of the end cap 130 with the external threads 113 on the proximal portion of the handle 110.
[118] Fig. 11B illustrates a flowchart of an exemplary method 1200 of operation of the PAS 100, of the present disclosure during a clinical procedure will now be described in a stepwise manner.
[119] The method commences at Step 1202 by coupling the catheter shaft 10 to the PAS 100 as described in the method 1100 of assembly in Fig. 11A above. That is, first a slider shaft 150 is fixed onto an outer surface of a catheter shaft 10 as stated above.
[120] At Step 1204, the distal end of the catheter shaft 10 is inserted into a puncture made in a body lumen of the patient and advanced through the patient’s vasculature such that the PAS 100 remains outside the patient’s body. The catheter shaft 10 is advanced until a distal end of the catheter shaft 10 is in as close proximity to the target treatment site as the operator can conveniently achieve.
[121] At Step 1206, the operator gradually rotates the roller 120 in a pre-defined direction such that the distal end of the catheter shaft 10 approaches the target treatment site. The rotation of the roller 120 rotates the inner shaft 140. The inner shaft 140 mimics the rotational motion of the roller 120 due to the coupling of the distal portion of the inner shaft 140 with the roller 120. The inner shaft 140 rotates within the lumen of the handle 110.
[122] At Step 1208, the rotational motion of the inner shaft 140 is translated to linear motion of the slider shaft 150 within the lumen of the handle 110. The engagement of the internal threads 145 of the inner shaft 140 with the first external threads 151 of the slider shaft 150 and the disposition of the projections 155 within the grooves 119, facilitate the slider shaft 150 to linearly move in the direction depending on the direction in which the roller 120 is rotated. For example, rotating the roller 120 in one direction moves the slider shaft 150 in, e.g., a forward direction. While rotating the roller 120 in the reverse direction moves the slider shaft 150 in, e.g., a backward direction. The user controls the rotational motion of the roller 120 thereby controlling the rotation of the inner shaft 140 and the translational motion of the slider shaft 150. The translational motion of the slider shaft 150 thus, corresponds to the rotational motion of the roller 120.
[123] At Step 1210, the linear motion of the slider shaft 150 is translated to linear motion of the catheter shaft 10. The disposition of the locking ring 160 and the cylindrical portion 173 (of the locking nut 170) within the cavity 157 of the slider shaft 150 enables the catheter shaft 10 to mimic the linear motion of the slider shaft 150. As a result, the catheter shaft 10 moves in the direction of the slider shaft 150. The rotation of the roller 120 in the chosen direction moves the distal end of the catheter shaft 10 towards the target treatment site. The operator continues rotating the roller 120 till the distal end of the catheter shaft 10 reaches the target treatment site location. The translational motion of the distal end of the catheter shaft 10 corresponds to the rotational motion of the roller 120. Thus, the user controls the rotational motion of the roller 120 due to which the translational motion of the catheter shaft 10 is controlled. Thereby, controlling the disposition of the distal end of the catheter shaft 10.
[124] At Step 1212, the catheter shaft 10 may be held firmly in position with the help of, for example, a catheter stand (not shown) and the clinical procedure at the target site is completed.
[125] At Step 1214, the operator retracts the catheter shaft 10 from the patient’s body lumen after the entire procedure is completed.
[126] It may be noted that the Steps 1204, 1212 and 1214 are exemplary as they are related to the clinical treatment. These steps may change based on the specific clinical treatment for which the catheter is used. These exemplary steps are mentioned only to illustrate the functioning of PAS 100.
[127] In an exemplary embodiment, the PAS 100 is used to advance/retract the catheter shaft 10 by 15 mm to 30 mm depending on the lengths of the internal threads 145 of the inner shaft 140 and the first external threads 151 of the slider shaft 150. As mentioned earlier, the extent of movement of the catheter shaft 10 may be less than 15 mm or more than 30 mm depending on the requirements of the medical procedure. This can be achieved by varying the lengths of the internal threads 145 of the inner shaft 140 and the first external threads 151 of the slider shaft 150.
[128] Although the PAS 100 is described with the example of roller 120 to move the slider shaft 150 (and the catheter shaft 10) in forward or backward directions (i.e., in a proximal or a distal direction), other functionally equivalent structures are within the scope of the teachings of the present disclosure.
[129] For example, Figs. 12 and 12a depict another embodiment of the PAS 200. The PAS 200 is structurally and functionally similar as PAS 100 (as described above). However, the PAS 200 does not include the roller 120 and the inner shaft 140 as provided in PAS 100. The PAS 200 is provided with a handle 210, an end cap 230, a slider shaft 250, a locking ring 260, a locking nut 270, etc. The locking ring 260 is same as the locking ring 160 of PAS 100. Similarly, the locking nut 270 and the end cap 230 are same as the locking nut 170 and the end cap 130 in PAS 100. The slider shaft 250 does not include first external threads 151 as provided in the slider shaft 150 of PAS 100.
[130] The PAS 200 includes a slider projection 250. The slider projection 280 is coupled to the slider shaft 250. The slider shaft 250 is fixed onto the outer surface of the catheter shaft 10, as explained earlier. The slider projection 280 is configured to move both in forward direction and backward direction (i.e., either of the proximal or distal direction) at a time. The translational motion of the slider projection 280 is reciprocated by the slider shaft 250. The slider projection 280 controls the translational motion of the slider shaft 250. The handle 210 of this embodiment is somewhat different as it does not include the roller 120, and inner shaft 140 of the PAS 100. The description of components of PAS 200 which are same as the components of PAS 100 is not repeated for sake of brevity and can be referred therefrom.
[131] In this embodiment, the opening 211 for the catheter shaft 10 on the distal portion D of the handle 210 and the opening 212 in the end cap 230 on the proximal portion P of the handle are sized to allow sliding of the catheter shaft 10 and also act as a guide for the catheter shaft 10. Additionally, the axially extending groove 219 provided in the handle 210 (similar to the groove 119 in the handle 110 of PAS 100) acts as a guide for linear movement of the slider shaft 250 with the help of at least one projection 255 on the slider shaft 250 (similar to the projections 155 on the slider shaft 150 of PAS 100 as shown in Fig. 6b). Thus, preventing rotation of the slider shaft 250 with respect to the handle 210. In an exemplary embodiment, the number of projections 255 correspond to the number of axially extending grooves 219 provided within a handle 210. Additional projections may be provided for the slider shaft 250 within the handle 210 as the slider shaft 250 does not include first external threads 151. The additional projection is marked as 255’, depicted in Fig. 12a.
[132] The slider projection 280 protrudes out of the handle 210 through a longitudinal slot 213 in the handle 210. The operator slides the sider projection 280 across the length of the longitudinal slot 213. In response to the sliding motion of the slider projection 280, the slider shaft 250 also slides along the length of the longitudinal slot 213 provided in the handle 210 in forward and backward direction. The slot 213 is shown in Fig. 12b which is the top view of the handle 210. As the catheter shaft 10 is coupled to the slider shaft 250 with the help of the locking ring 260 and locking nut 270 (as described for PAS 100 for the slider shaft 150), it mimics the sliding (linear) motion of the slider projection 280. The operator can hence move the distal end of the catheter shaft 10 in a controlled manner under guidance of fluoroscopy or any other imaging procedure by moving the slider projection 280 in forward and backward directions. The length of axial movement of the catheter shaft 10 depends on the length of a longitudinal slot 213 in the handle 210.
[133] The position of the slider projection 280 on the handle 210 will give an indication of its movement to the operator. In addition, the PAS 200 may be provided with one or more visual indicator/indicia to indicate position of the slider projection 280 on the handle 210 as described with reference to Figs. 9 – 11. Fig. 12b shows an indicia 214 as an example.
[134] Fig. 12c depicts an exploded view of the PAS 200 without the catheter shaft 10. The PAS 200 extends between a proximal end P and a distal end D. Fig. 12c shows all the components of PAS 200 viz. a handle 210, an end cap 230, a slider shaft 250, a locking ring 260, a locking nut 270, etc. The handle 210 is shown in two parts viz. 210A and 210B. However, the handle 210 may be a single integral component. The slider shaft 250 is shown with two projections viz. 255 and 255’. However, there may be a single projection or more than two projections. Two projections are preferable to impart stability to the slider shaft 250 because there is no inner shaft in this embodiment.
[135] The method of assembly of PAS 200 is similar to that of PAS 100 described above in Fig. 11A above with the difference that PAS 200 does not have the inner shaft 140 and the roller 120 and also the slider projection 280 protrudes out from the slot 213 in the handle 210.
[136] The method of operating PAS 200 is similar to that of PAS 100 except that the operator pushes the slider projection 280 in forward and backward direction (in place of rotating the roller) to move the catheter shaft 10 in the desired direction.
[137] The shape of the slider projection 280 shown in this embodiment is exemplary and it may be of any shape that is convenient for easy movement.
[138] In an embodiment where the translational movement is to be achieved by a controlled sliding motion, the catheter shaft 10 is locked with the slider shaft 250 which the operator can slide in a controlled manner. The slider projection 280 is provided on the slider shaft 250 that protrudes out from the handle 210 through a longitudinal slot 213. The operator may impart a translational motion to the slider projection 280 both in the proximal direction and the distal direction at a time.
[139] As the slider projection 280 is coupled to the slider shaft 250, the translational motion of the slider projection 280 is reciprocated by the slider shaft 250 in the corresponding direction (i.e., either of the proximal or distal direction). In other words, the slider projection 280 and the slider shaft 250 move in a same direction. The catheter shaft 10, being coupled to the slider shaft 250, also moves in the corresponding direction. The extent of the axial movement of the catheter shaft 10 corresponds to the length of the translational motion of the slider projection 250. Thus, by controlling the translational motion of the slider projection 280, the user may control the axial movement of the catheter shaft 10. Consequently, controlling a position of the distal end of the catheter shaft 10.
[140] This specification describes the details of a PAS 100/200 of a preferred embodiment. A skilled person can make variations in the construction of various components to achieve the same solution using the basic principles described herein. As mentioned earlier, it will be apparent to a skilled person that the PAS 100/200 of the present disclosure can function even when orientation of the PAS is revered i.e. the roller 120 in PAS 100 is positioned at the proximal end P and the end cap 130 in PAS100/200 is positioned at the distal end D.
[141] 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. , Claims:WE CLAIM:
1. A park assist system (100) provided on a catheter shaft (10), the park assist system (100) comprising:
a slider shaft (150) fixed rigidly onto an outer surface of a catheter shaft (10);
an inner shaft (140) operatively coupled to the slider shaft (150); and
a roller (120) operatively coupled to a distal portion of the inner shaft (140), the roller (120) upon rotation, is configured to control a translational motion to the slider shaft (150) via the inner shaft (140), thereby positioning a distal end of the catheter shaft (10) accurately at a treatment site.
2. The park assist system (100) as claimed in claim 1 wherein, the translational motion of the slider shaft (150) moves the catheter shaft (10) in the direction of the slider shaft (150).
3. The park assist system (100) as claimed in claim 1 wherein, when the roller (120) is rotated in one direction, the slider shaft (150) is configured to move in a forward direction and when the roller (120) is rotated in a reverse direction, the slider shaft (150) is configured to move in a backward direction.
4. The park assist system (100) as claimed in claim 1 wherein, the roller (120) includes a plurality of pins (123a).
5. The park assist system (100) as claimed in claim 1 wherein, the roller (120) is coupled to the inner shaft (140) by at least one of adhesive, wires, or suturing.
6. The park assist system (100) as claimed in claim 1 wherein, outer surface of the inner shaft (140) includes at least two flanged portions spaced from each other.
7. The park assist system (100) as claimed in claim 6 wherein, the at least two flanged portions include a first flanged portion (141) having at least one hole (141a).
8. The park assist system (100) as claimed in claim 7 wherein, the first flanged portion (141) is disposed within the roller (120) such that the pins (123a) of the roller (120) are disposed within the hole/s (141a) of the first flanged portion (141).
9. The park assist system (100) as claimed in claims 4 and 7 wherein, the number of holes (141a) provided on the first flanged portion (141) is equal to number of pins (123a).
10. The park assist system (100) as claimed in claim 6 wherein, the at least two flanged portions include a second flanged portion (143) disposed within a groove (117) of a handle (110) to restrict axial movement of the inner shaft (140) with respect to the handle (110).
11. The park assist system (100) as claimed in claim 10 wherein, the handle (110) is one of a single integral unit or includes an upper part (110a) and a lower part (110b).
12. The park assist system (100) as claimed in claim 10 wherein, the roller (120) is snap-fitted or press-fitted over an end portion (111) of the handle (110).
13. The park assist system (100) as claimed in claim 10 wherein, the roller (120) includes one or more projections inside a first tubular opening (121) that press-fit in corresponding cavities of the handle (110).
14. The park assist system (100) as claimed in claim 1 wherein, an outer surface of the slider shaft (150) includes a plurality of first external threads (151) and a plurality of second external threads (153).
15. The park assist system (100) as claimed in claims 1 and 14 wherein, at least a portion of an inner surface of a lumen of the inner shaft (140) is provided with a plurality of internal threads (145) configured to engage with at least a portion of the first external threads (151) on the slider shaft (150).
16. The park assist system (100) as claimed in claim 14 wherein, the plurality of second external threads (153) at least partially receive a locking nut (170).
17. The park assist system (100) as claimed in claim 1 wherein, the slider shaft (150) is provided with at least one projection (155).
18. The park assist system (100) as claimed in claim 17 wherein, the number of projections (155) correspond to the number of axially extending grooves (119) provided within a handle (110).
19. The park assist system (100) as claimed in claim 1 wherein, the park assist system (100) includes a locking ring (160) having an internal diameter ‘D1’ and an external diameter ‘D2’ such that the internal diameter ‘D1’ is either smaller than or equal to the diameter of the catheter shaft (10) on which the park assist system (100) is to be coupled.
20. The park assist system (100) as claimed in claim 1 wherein, the park assist system (100) includes a locking nut (170) provided with a plurality of internal threads (171a) in at least a portion of its inner surface to engage with the second external threads (153) of the slider shaft (150) to secure the locking nut (170) to the slider shaft (150).
21. The park assist system (100) as claimed in claim 1 wherein, length of axial movement of the catheter shaft (10) depends on the length of the internal threads (145) of the inner shaft (140) and length of the first external threads (151) of the slider shaft (150).
22. A park assist system (200) provided on a catheter shaft (10), the park assist system (200) comprising:
a slider shaft (250) fixed rigidly onto an outer surface of a catheter shaft (10);
a slider projection (280) fixed onto the slider shaft (250) to control a translational motion to the slider shaft (250), the slider projection (280) being configured to move in a proximal or a distal direction at a time;
wherein, the length of the translational motion of the slider shaft (250), defines extent of axial movement of the catheter shaft (10) in the direction of motion of the slider shaft (250), thereby accurately positioning a distal end of the catheter shaft (10) at a treatment site.
23. The park assist system (200) as claimed in claim 22 wherein, the slider projection (280) and the slider shaft (250) are configured to move in a same direction.
24. The park assist system (200) as claimed in claim 22 wherein, an outer surface of the slider shaft (250) includes a plurality of second external threads (153).
25. The park assist system (200) as claimed in claim 24 wherein, the plurality of second external threads (153) at least partially receive a locking nut (270).
26. The park assist system (200) as claimed in claim 22 wherein, the slider shaft (250) is provided with at least one projection (255).
27. The park assist system (200) as claimed in claim 26 wherein, the number of projections (255) correspond to the number of axially extending grooves (219) provided within a handle (210).
28. The park assist system (200) as claimed in claim 27 wherein, the handle (210) is one of a single integral unit or includes an upper part 210A and a lower part 210B.
29. The park assist system (200) as claimed in claim 22 wherein, the park assist system (200) includes a locking ring (260) having an internal diameter ‘D1’ and an external diameter ‘D2’ such that the internal diameter ‘D1’ is either smaller than or equal to the diameter of the catheter shaft (10) on which the park assist system (200) is to be coupled.
30. The park assist system (200) as claimed in claim 24 wherein, the park assist system (200) includes a locking nut (170) provided with a plurality of internal threads (171a) in at least a portion of its inner surface to engage with the second external threads (153) of the slider shaft (250) to secure the locking nut (270) to the slider shaft (250).
31. The park assist system (200) as claimed in claim 22 wherein, the park assist system (200) includes a longitudinal slot (213) in a handle (210).
32. The park assist system (200) as claimed in claim 31 wherein, length of the longitudinal slot (213) defines the length of axial movement of the catheter shaft (10).
33. The park assist system (200) as claimed in claim 31 wherein, the slider projection (280) protrudes outside the longitudinal slot (213).
34. A method to control a position of a distal end of a catheter shaft (10) using a park assist device (100), the method comprising:
a. fixing a slider shaft (150) onto an outer surface of a catheter shaft (10);
b. imparting a rotational motion to a roller (120) coupled to a distal portion of an inner shaft (140), the inner shaft (140) operatively coupled to the slider shaft (150);
c. controlling a translational motion of the slider shaft (150) via the inner shaft (140), the translational motion of the slider shaft (150) corresponds to the rotational motion of the roller (120); and
d. controlling a translational motion of the catheter shaft (10) to control a position of the distal end of the catheter shaft (10), the translational motion of the catheter shaft (10) corresponds to the rotational motion of the roller (120).
35. A method to control a position of a distal end of a catheter shaft (10) using a park assist device (200), the method comprising:
a. fixing a slider shaft (250) onto an outer surface of a catheter shaft (10);
b. imparting a translational motion to a slider projection (280) in a proximal or a distal direction at a time, the slider projection (280) coupled to the slider shaft (250);
c. controlling a translational motion of the slider shaft (250), the translational motion of the slider shaft (250) corresponds to the translational motion of the slider projection (280); and
d. controlling an axial movement of the catheter shaft (10) in the direction of the translational motion of the slider projection (280) to control a position of the distal end of the catheter shaft (10), the extent of axial movement of the catheter shaft (10) corresponds to the length of the translational motion of the slider projection (250).