Claims: A catheter comprising: a. an outer tube having a distal end and a proximal end, the outer tube comprising a plurality of holes towards the distal end; b. an inner tube coaxially placed with the outer tube, the inner tube having a 5 distal end and a proximal end, the distal end of the inner tube permanently attached to the distal end of the outer tube, the inner tube comprises a rigid material; and c. an expandable member mounted towards the distal end of the outer tube, the expandable member enclosing the plurality of holes. 10 2. The catheter as claimed in claim 1, wherein the outer tube comprises a polymer. 3. The catheter as claimed in claim 1, wherein the outer tube comprises a multi-sectional outer tube. 4. The catheter as claimed in claim 1, wherein the outer tube comprises an 15 antifungal and/or antibacterial . 5. The catheter as claimed in claim 1, wherein the outer tube comprises a plurality of markers disposed on its surface. 6. The catheter as claimed in claim 1, wherein the distal end of the inner tube has a curvature of predefined angle, the curvature can be one of 60-80°C for frontal 20 sinus, 0-30°C for sphenoid sinus, or 85-135°C for maxillary sinus. 7. The catheter as claimed in claim 1, wherein the distal end of the inner tube comprises a malleable material to provide a curvature of a predefined angle to the inner tube.
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8. The catheter as claimed in claim 1, wherein the distal end of the inner tube is coupled to an atraumatic tip. 9. The catheter as claimed in claim 1, wherein the inner tube comprises a lumen through which a fiber optic cable is provided. 10. The catheter as claimed in claim 9, wherein the fiber optic cable is fixedly 5 coupled to the inner tube. 11. The catheter as claimed in claim 9, wherein the fiber optic cable is movably coupled to the inner tube. 12. The catheter as claimed in claim 1, wherein the plurality of holes assists in inflating/deflating the expandable member on passage of a fluid. , Description:FIELD OF THE INVENTION [001] The present disclosure relates generally to devices, and more particularly to dilation instruments.
BACKGROUND 5 [002] Paranasal sinus includes four paired air filled spaces namely Frontal sinus, Ethmoid sinus, Sphenoid sinus and Maxillary sinus surrounding the nasal cavity. The paranasal sinus is lined with mucous producing epithelial tissue. Mucous produced by the epithelial tissue slowly drains out of sinus through an opening known as an ostium. Inflammation of the epithelial tissue of the passageways may block the 10 cavities through which mucous is drained out leads to a condition known as sinusitis. The term “sinusitis” refers generally to any inflammation or infection caused by bacteria, viruses, fungi (molds), allergies or combinations thereof. [003] One of the ways to treat sinusitis is to use drugs such as anti-inflammatory drugs or antibiotics. However, a number of patients do not respond to drug therapy. 15 Other way to treat sinusitis is to open paranasal sinus via surgery. One of such surgeries is functional endoscopic sinus surgery (FESS). However, FESS can cause significant post-operative pain as some FESS procedures are associated with significant post-operative bleeding and, as a result, nasal packing is frequently placed in the patient's nose for some period of time following the surgery. Such 20 nasal packing can be uncomfortable and can interfere with normal breathing, eating, drinking etc. [004] Another technique to treat sinusitis is by using balloon sinuplasty. In balloon sinuplasty, a dilatation catheter such as a balloon catheter or other type of dilator is advanced through the nose or some other entry path into a patient's nose to a 25
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position within the ostium of a paranasal sinus or other location, without requiring removal or surgical alteration of other intranasal anatomical structures. [005] The dilatation catheter is then used to dilate the ostium or other anatomical structures. In some cases, a tubular guide such as a guide tube may be initially inserted through the nose and advanced to a position near the sinus ostium, to 5 reach the affected paranasal sinus. However, introduction of the tubular guide may result in repeated intrusion of devices into the patient's paranasal cavity and may correspondingly result in increased tissue trauma, increased post-operative recovery time, and/or increased surgery time (and thus cost) involved in the procedure.
SUMMARY 10 [006] In accordance with an embodiment of the present invention, a catheter that overcomes the aforesaid drawbacks is provided. The catheter may be a balloon catheter used in sinuplasty. The catheter includes an outer tube having a distal end and a proximal end, the outer tube comprising a plurality of holes towards the distal end; an inner tube coaxially placed with the outer tube, the inner tube comprises a 15 rigid material, the inner tube having a distal end and a proximal end, the distal end of the inner tube permanently attached to the distal end of the outer tube; and an expandable member mounted completely towards the distal end of the outer tube and enclosing the plurality of holes, thereby eliminating the need for a guidewire. [007] The catheter of the above construction is a single-piece device in which the 20 various components are fixed and not movable with respect to each other.
BRIEF DESCRIPTION OF THE DRAWINGS [008] 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 25
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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. Wherever possible, like elements have been indicated by identical numbers. [009] FIG. 1 illustrates a two dimensional cross-sectional view of a balloon catheter 5 in accordance with an embodiment of the present invention. [010] FIG. 2 illustrates a perspective view of a balloon catheter in accordance with an embodiment of the present invention. [011] FIG. 3 illustrates a flow chart depicting insertion of a balloon catheter into sinus in accordance with embodiment of the present invention. 10
DESCRIPTION OF THE PREFERRED EMBODIMENTS [012] This disclosure is not limited to particular embodiments described, but includes variations that may be practiced as per the teachings of the present disclosure. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be 15 limiting. [013] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It must be noted that as used herein, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates 20 otherwise. Thus, for example, reference to “a tube” includes a plurality of such tubes and reference to “the shaft” includes reference to one or more shafts and equivalents thereof known to those skilled in the art, and so forth. [014] In accordance with the present disclosure, there is provided a dilation instrument with navigational capabilities for dilating an opening of a paranasal sinus 25
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in a human or animal subject. The term opening of a paranasal sinus as used herein shall, unless otherwise stated, include any and all trans-nasally accessible opening in a paranasal sinus or air cell including but not limited to; natural ostia, surgically altered natural ostia, surgically created openings, antrostomy openings, ostiotomy openings, burr holes, drilled holes, ethmoidectomy openings, natural or man-made 5 passageways, etc. [015] The present invention discloses a balloon catheter more particularly to a balloon sinuplasty catheter used in the treatment of patients suffering from chronic sinusitis, which is easy to operate and construct. The balloon catheter can be delivered to a patient easily as it is a single fixed assembly and post treatment, 10 recovery time is very less as it does not cause any damage to the epithelial lining of the nasal tissue as the balloon catheter can be inserted to the desired location in one go. [016] Referring specifically to drawings, FIG. 1 illustrates a cross-sectional view of a catheter 100 which includes an outer tube 10, an inner tube 20, an fiber optic cable 15 30, an expandable member 40, one or more markers 50, an atraumatic tip 60, and a rigid tube 70. [017] The outer tube (or flexible shaft) 10 has a proximal end 12 and a distal end 14 with a lumen 16 extending from the proximal end 12 to the distal end 14 to provide a passage way for components like inner tube 20. The outer tube 10 may be made 20 of a flexible polymer such as nylon, plutonium, High-density polyethylene (HDPE), pebax, etc. The outside diameter of the outer tube 10 may range from 1.5 mm to 2 mm with a wall thickness ranging from 0.125 to 0.3 mm in accordance with the paranasal anatomy of a patient. In an embodiment, the outer tube includes an antifungal and/or antibacterial . 25
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[018] In an embodiment, a multi-sectional outer tube can also be used in place of the single section outer tube 10 as described in the present disclosure. [019] The inner tube 20 has a proximal end 22 and a distal end 24. The inner tube is positioned coaxially within the outer tube 10 of the catheter 100. The inner tube 20 is an elongated body with a lumen 26 extending from the proximal end 22 to the 5 distal end 24. The inner tube 20 can be a stainless steel hypotube. Alternately, the inner tube 20 can be made of nitinol, titanium and/or other shape memory alloy. The shape memory alloy enables the inner tube 20 to remember its previous shape if deformed. The outer diameter of the inner tube 20 may range from 1.22 mm to 1.56 mm with a wall thickness ranging from 0.16 to 0.6 mm. 10 [020] The distal end 24 of the inner tube 20 may have a fixed predefined angle with respect to the proximal end 22. Alternately, the distal end 24 of the inner tube 20 may be malleable to bend it with the help of a guiding tool to achieve a required angle for treatment of various sinuses like frontal, ethmoid, maxillary and sphenoid. The angulation of the distal end 24 of the inner tube 20 is customized based upon 15 nasal anatomy for various sinuses. As an example, the front part is curved approximately 60-80°C for frontal sinus, 0-30°C for sphenoid sinus, and 85-135°C for maxillary sinus, etc. [021] In an embodiment, the inner tube 20 includes an illumination means in its lumen 26 such as, a fiber optic cable 30 that extends fully through the lumen 26. 20 Towards the distal end, the fiber optic cable 30 may attain the curvature of the distal end 24 of the inner tube 20. The inner tube 20 is configured to receive light from a light source through the fiber optic cable 30. The fiber optic cable 30 within the catheter 100 can be configured movable along the length of the inner tube 20 or may be fixed at the proximal end of the catheter 100. 25
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[022] The expandable member (or dilation member) 40 such as a balloon is provided over the outer tube 10 to dilate the sinus. For example, the expandable member 40 may be entirely mounted on the outer tube 10. The expandable member 40 may be made of materials such as PET, POC, HDPE or preferably polyether block amide (PEBAX) of a predefined diameter ranging from 3 mm to 8 mm according to the 5 nasal anatomy of a patient. The expandable member 40 may have a proximal neck 42, distal neck 44 and a middle portion 46. Both, the proximal neck 42 and the distal neck 44 are mounted over the outer tube 10 towards distal end 14 of the outer tube 10 by means of for example, thermal bonding using adhesives preferably urethane or any other suitable means. 10 [023] The outer tube 10 is provided with a plurality of holes 18 in the region where the expandable member 40 is mounted. These holes 18 are enclosed by the middle portion 46 of the expandable member 40. Holes 18 on the outer tube 10 can be either circular or non-circular in shape. Holes 18 may be arranged in the form of an array on the outer tube 10 or may be arranged randomly. The holes 18 are provided 15 to inflate or deflate the expandable member 40 during treatment of inflamed sinus by injecting or retrieving a fluid (for example, saline) from the lumen 16 of the outer tube 10. [024] Several position indicators/ markers 50 are provided over the outer tube 10 for adequate positioning of the catheter 100. The markers can be of platinum-20 Iridium alloy or radiopaque materials. The method of securing a marker on the outer tube 10 can be by way of adhesion, swagging or cold forging process, etc. In an embodiment, the markers 50 are secured on the outer tube 10 by means of printing. Each marker band may have a length ranging from 1 mm to 5 mm. [025] The atraumatic tip 60 may be a soft polymer material attached at the distal 25 end 14 of the outer tube 10. The outer tube 10, the inner tube 20 and the
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atraumatic tip 60 may be heat welded at the end of the catheter 100 to close the distal end of the catheter 100. [026] The catheter 100 includes a rigid tube 70. The rigid tube 70 has a proximal end 72 and a distal end 74. A portion of the outer tube 10 is positioned coaxially within the rigid tube 70 of the catheter 100. The rigid tube 70 is an elongated body with a 5 lumen 76 extending from the proximal end 72 to the distal end 74. The rigid tube 70 can be made of an alloy preferably stainless steel and is used to provide stiffness for easy handling of the catheter 100. [027] FIG. 2 illustrates a perspective view of the catheter 100 of FIG. 1 with a multi-port hub 80, for example, a two-port hub. 10 [028] The rigid tube 70 is connected with the two port hub 80 at its proximal end 72. The two port hub 80 typically includes a guiding port 82 and an inflation port 84. Guiding port 82 communicates with the inner lumen 26 of the inner tube 20 which in turn can be provided with a passage for the fibre optic cable 30 as shown in FIG. 1. The inflation port 84 is in fluid communication with the annular lumen 16 15 between the inner tube (not shown) and the coaxially disposed outer tube 10 which in turn is in fluid communication with the interior of the expandable member 40. [029] Though the Figure is depicted with two-port hub, the number of hubs can be varied as per the requirement. [030] FIG. 3 illustrates a flow chart depicting the process of operation of the 20 catheter 100 in accordance with an embodiment of the present invention. In various embodiments, a catheter includes one or more sinus dilation instruments. However, the instrument is sized and shaped for locating a balloon carried thereby at a particular targeted sinus region (e.g., frontal sinus, maxillary sinus, or sphenoid sinus) via a patient's naris or alternatively sized and shaped for accessing the 25
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targeted sinus region through other conventional approaches such as canine fossa or open approach. The expandable member 40 is selectively fluidly connected to the catheter 100 via the inflation port 84. With this construction, use of the catheter 100 in treating the paranasal, maxillary sinus etc. may require optical coupling of the appliance. Once connected, the optical coupling provides the surgeon with visual 5 representations of the catheter 100 relative to the patient's anatomy. [031] The process of operating the catheter commences at the step 101 wherein the catheter is inserted into a blocked nasal passage or nasal ostium. The catheter is aligned with respect to the blocked nasal passage as desired. After accurate alignment of the catheter in the nasal passage, the inflation port 84 is operated to 10 inflate the expandable member 40. At the step 103, a fluid (say, saline) is passed through the inflation port 84 that traverses the entire length of the lumen 16 of the outer tube 10. Towards the distal end 14, the fluid passes from the holes 18 into the area enclosed between the outer tuber 10 and the expandable member 40. The amount of fluid to be passed can be controlled at the inflation port and may vary 15 due to several factors, like the amount of inflation of the expandable member desired, etc. Once the expandable member 40 is inflated, it causes expansion of the sinus ostium or other region of the accessed sinus as required. In other words, the inflated expandable member 40 causes the sinus opening to expand by restructuring and widening the walls of the sinus passageway while maintaining the integrity of 20 the sinus lining. [032] Following restructuring or expansion of the nasal passage, the inflation port is 84 is further operated to deflate the balloon at the step 105. In this step, the fluid is withdrawn from the expandable member 40 with the help of inflation port 84. Techniques used for withdrawing the fluid may include suction etc. 25
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[033] Lastly, the catheter 100 having deflated expandable member 40 is removed leaving the nasal passage widened at the step 107. Infected mucus etc. present inside the blocked sinus may thereafter drain or be removed using an external device. [034] In one embodiment where a fibre optic cable 30 is to be deployed and is 5 movably coupled to the inner tube 20, the fibre optic cable 30 may be inserted after the catheter 100 is placed in order to accurately place the catheter inside the nasal ostium. [035] In another embodiment where a fibre optic cable 30 is to be deployed and is fixedly coupled to the inner tube 20, the fibre optic cable 30 is inserted into the 10 nasal ostium together with the catheter 100. A surgeon may move the catheter as required during placement for illumination of the nasal ostium via the cable 30. [036] In some embodiments, the system includes two or more of the sinus dilation instruments, each sized and shaped for accessing a different sinus region of a patient (via an intranasal approach). Once the surgeon has determined the 15 paranasal sinus to be treated, the surgeon selects the appropriately sized and shaped sinus dilation instrument, optically connects the selected instrument and then performs the procedure as outlined above. [037] The whole catheter assembly 100 is bounded within the handle as an integrated single unit or single piece. In conventional catheter, guide catheter is 20 initially inserted into the nose followed by a guide wire through the guide catheter, a balloon catheter is then passed over the guide wire. The present invention discloses a catheter with a single or an integrated assembly. The features disclosed in the present invention eliminate the need of using separate wires, thereby making the whole process of treatment extremely simplified for doctors. It reduces the time 25 of operation of appliance as it can be delivered to the patient in short time.
[038] In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the disclosure and should not be taken as limiting the scope of the present disclosure.