US 20070123924 A1
A balloon catheter for treatment of a patient's lacrimal system is applied transnasally without the use of a guide wire or a curve retention member. The catheter is formed of a stainless steel hypotube and is of sufficient stiffness and column strength to enable the deflated catheter to be pushed from the patient's nasal cavity through a prepared small-tight opening, which is formed through the lateral nasal wall and lacrimal fossa, into the lacrimal sac. The catheter has a proximal shaft and a distal segment positioned by a bend at an angle of 70° to 115°, preferably 90°, to the proximal shaft. An inflatable member is mounted about the distal segment and is adhesively bonded to the distal end of the proximal shaft, the bend, and the proximal end of the distal segment and to the distal portion of the distal segment. The prepared, small-tight opening is formed by pushing small holes through the medial sac, lacrimal fossa, and lateral nasal wall with an instrument and coalescing the holes to form the prepared small-tight opening. The catheter is introduced into the nasal cavity and rotated, or moved, to align the distal segment with the prepared opening. The distal segment is then pushed through the prepared opening, and fluid under pressure is applied to the catheter to inflate the inflatable member and dilate the prepared opening.
1. A device for dilating an opening between a patient's lacrimal sac and nasal cavity to treat the: lacrimal system, comprising:
a tubular body, said tubular body having a proximal end, a proximal segment, a distal end, a distal segment, said distal segment having a fixed angle relative to said proximal segment, and said tubular body having sufficient compressive strength to resist buckling and sufficient lateral stiffness to retain said angle when correctly utilized during treatment;
a luer, said luer fixedly attached to said proximal end;
an inflatable member, said inflatable member being proximate to said distal segment, said inflatable member, when inflated, having a center region sufficiently dimensioned to dilate said opening.
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This is a divisional of U.S. patent application Ser. No. 10/259,630, filed Sep. 30, 2002, now U.S. Pat. No. 7,169,163 issued Jan. 30, 2007.
This invention relates to a method and catheter for treating the lacrimal system and, more particularly, to a transnasal method of treating the lacrimal system and a balloon catheter used in this method.
To fully understand the invention, it is necessary to consider the anatomy and physiology of the lacrimal system. The orbital portion of the lacrimal gland is located in the superotemporal orbit and produces the aqueous layer of the tear film. Ductules from the orbital portion of the lacrimal gland pass through the adjacent palpebral lacrimal gland to empty in the superior conjunctival cul-de-sac. Smaller accessory lacrimal glands in the upper and lower lids also contribute to tear production The tears bathe the surface of the eye and then drain into the puncta and canaliculi in the medial upper and lower lids. The tears flow from the canaliculi into the lacrimal sac down the nasolacrimal duct into the nose.
The nasolacrimal duct can become obstructed on either a congenital or acquired basis When the nasolacrimal duct becomes obstructed, tears can no longer drain from the surface of the eye through the lacrimal system into the nose. The tears well up over the eye and spill over the lids onto the face. The patient has to constantly dab the eye with a tissue. In addition, tears stagnate in the lacrimal sac, bacteria multiply, and in many cases the lacrimal sac becomes infected (dacryocystitis). Dacryocystitis causes the lacrimal sac to become swollen, red and painful. Pus exudes from the sac and constantly covers the eye. In time, the dacryocystitis does not respond to antibiotics and surgery becomes necessary. At present, there is no medical therapy for acquired nasolacrimal duct obstruction other than antibiotics to temporarily suppress infection.
The condition can, however, be corrected surgically. Dacryocystorhinostomy (DCR) is the surgery required to correct nasolacrimal duct obstruction. In a DCR, a new opening (ostium) is created between the lacrimal sac and the nose. This allows tears to flow from the lacrimal sac through the DCR ostium into the nose. An external or incisional DCR required an incision on the side of the nose. In an open DCR, the surgeon creates a large 17 mm plus diameter opening in the bone and nasal muscosa. This procedure has significant morbidity, a prolonged recovery, and the threat of scarring and hemorrhage. In contrast, an endoscopic DCR has much less morbidity, no incision, and a quick recovery time. An endoscopic DCR may be performed using a balloon catheter, a laser, or traditional surgical instruments. A laser endoscopic DCR requires expensive and time-consuming lasers, and has a low success rate. An endoscopic DCR with traditional instruments places the eye and surrounding structures at risk because tissue is removed from the lacrimal sac and lateral nasal wall, with the instruments in the nasal cavity going toward the eye and orbit. Bleeding and edema may make it difficult to identify the relevant structures.
It has been found that a balloon catheter DCR is a much safer and cheaper form of DCR than a laser or an endoscopic DCR with traditional surgical instruments. The balloon catheter is positioned so that it extends from the lacrimal sac through the ostium and extends into the nose. Since the balloon DCR ostium is created by dilatation, rather than by excision or laser energy, there is no threat to the surrounding ocular and orbital structures, and there is less tissue trauma.
As shown in U.S. Pat. Nos. 5,021,043 and 5,169,043, I have previously co-invented balloon catheters for use in the lacrimal system. These balloon catheters are inserted from the eye through the small diameter (about 0.5 mm) delicate punctum and canaliculus into the lacrimal sac extending through the planned ostium into the nose. The deflated profile diameter of the balloon catheter must be very small in order to be pushed through, and avoid damage to, the small diameter and delicate canaliculus. The need for such a small deflated diameter limits the inflated diameter of the balloon to 5 mm. However, a 5 mm diameter ostium is much smaller than the 17 mm plus diameter ostium of an external DCR and leads to a higher stenosis rate of the balloon DCR ostium after surgery. A larger diameter balloon would create a larger-diameter ostium and lead to a higher surgical success rate.
This led to the concept disclosed beginning at column 7, line 29, and
The U.S. Pat. No. 5,169,386 patent also discloses an alternative dilation catheter, which does not use a guide wire, but there is no suggestion that this catheter be inserted transnasally. The catheter is constructed to simulate a standard ophthalmic probe in stiffness, in terms of both column strength and resistance to lateral bending, with sufficient flexibility to enable it to conform to the contours of the lacrimal system. The catheter, as provided, is initially straight, but the catheter may be bent between 0°-30° to simulate the curvature of an ophthalmic probe. A curve retention element is inserted in the catheter to retain the curved shape and to increase the columnar and flexural stiffness of the distal portion of the catheter to enhance its ability to be forced through a constricted portion of the lacrimal system. The catheter is formed of a stainless steel hypotube having an outer diameter of 0.022″ and an inner diameter of 0.017″.
This catheter is not suitable for transnasal insertion. The tube does not have sufficient stiffness and column strength to enable the deflated balloon catheter to be pushed from the nasal cavity through a small, tight opening in the lateral nasal wall and lacrimal fossa into the lacrimal sac. Moreover, the bent distal portion is not angled to a degree necessary for ready insertion through the opening.
A balloon catheter of the invention can be introduced transnasally into the area of a planned DCR ostium. The catheter has a larger deflated profile and, thus, a larger inflated diameter, than a balloon catheter introduced through the delicate canaliculi. The balloon catheter of the invention does not need a guide wire; and, therefore, there is no chance that a guide wire will damage the delicate canaliculi. A larger diameter balloon DCR ostium is less likely to stenose after surgery and results in a better surgical success rate.
The balloon catheter of the invention comprises a hypotube formed of stainless steel of sufficient stiffness and column strength to enable the deflated balloon catheter to be pushed from the nasal cavity through a prepared small, tight opening in the lateral nasal wall and lacrimal fossa into the lacrimal sac. A distal end segment of the hypotube has a rounded bend, placing the distal segment at an angle of 70° to 115°, preferably 90°, to a long proximal segment or shaft. This bend allows the surgeon to rotate or shift the position of the long proximal catheter shaft, thus placing the distal balloon catheter segment in position to enter from the nasal cavity into the lacrimal sac at various angles appropriate to each individual patient. Due to the stiffness and strength of the hypotube, neither a guide wire nor a curve retention element are necessary.
The distal segment of the balloon catheter from the outside of the bend to the end of the catheter is 14 mm which is short enough to allow it to be rotated within the nasal cavity and long enough to allow a balloon of sufficient length and diameter to be attached to the hypotube for dilatation of the balloon DCR ostium.
The balloon is formed of inflatable material with a first neck bonded with adhesive to the very distal portion of the distal segment of the hypotube and a second neck bonded with adhesive to the distal end of the proximal shaft, the bend, and the proximal end of the distal segment. This permits a longer working segment of balloon to be used, because the area of adhesion of the balloon includes the bend and the adjacent portion of the proximal long segment of the hypotube. The proximal end of the catheter tube has a luer lock with wings or an expansion to allow the catheter to be attached to tubing from the inflation device. The wings or expansion allow the surgeon to more easily hold, manipulate, and push the balloon catheter.
According to the method of the invention, a very large ostium is formed between the lacrimal sac and the nasal cavity with the use of a very large balloon inserted transnasally. The balloon is deflated to allow the catheter, which is of sufficient stiffness, to be pushed through the prepared opening formed from the nasal cavity through the lateral nasal wall and lacrimal fossa into the lacrimal sac The balloon is then inflated to enlarge the opening and create the very large ostium. The balloon catheter is inserted without the use of a guide wire.
The portion of the distal end after the bend is sufficiently short to enable the catheter to be positioned in the nasal cavity to bring the distal end to the level of the prepared opening. The catheter is then rotated or shifted to align the distal end with the prepared opening, as required by the anatomy of the individual patient. The distal end is then pushed through the prepared opening to position the deflated balloon in the opening. The balloon is then inflated to enlarge the opening to the outer diameter of the inflated balloon, thus forming the very large ostium.
Since the method of the insertion requires insertion of the balloon catheter transnasally, the trauma associated with insertion through the delicate canaliculi is avoided. The catheter and method of the invention provide a satisfactory endoscopic DCR and thus avoid the trauma associated with an external (incisional) DCR. The catheter and method of the invention achieve a high surgical success rate.
As shown in
The catheter 130 has a port 140 in the distal segment 137, which is formed by inserting temporarily a discardable wire segment into the tube 136. This is done before inserting hypotube 136 into luer 144. A transverse slot is cut in the tube 136 approximately 2 mm to 14 mm, preferably 4 mm, from its distal end 184 to form port 40. The slot extends in depth to approximately one third of the diameter of tube 136. A wire wheel is used to remove any burrs, and the discardable core wire is removed and discarded.
Catheter 130 has sufficient column strength and resistance to lateral bending (stiffness) to enable the deflated catheter to be pushed through the initial prepared opening in the lateral nasal wall and lacrimal fossa into the lacrimal sac. This may require considerable pressure in some cases.
A balloon 134 is preferably formed of polyethylene terephthalate and has a length of approximately 4 mm to 30 mm, preferably 14 mm, and a working inflated diameter of 2 mm to 14 mm, preferably 9 mm, for use in the lacrimal system. The balloon has a distal neck 170, a distal tapered region 172, a center region 174, a proximal tapered region 176, and a proximal neck 178. During installation, tube 136 is cleaned with isopropanol and then coated with a primer, “Loctite 770.” The balloon is placed over the distal end of tube 136 to align the distal end of distal neck 170 with distal end 184 of tube 136. An adhesive, such as cyanoacrylate, is used. An acceptable adhesive “Loctite 4081” is available from Loctite Corporation. The adhesive is applied to distal end of distal neck 170 and the proximal end of proximal neck 178 to form bonds 180 and 182, respectively. The adhesive is applied to the balloon necks 170, 178 using a small mandrel such as a wire approximately 0.010″ to 0.014″ in diameter. The adhesive wicks into the necks due to capillary action. Proximal neck 178 and proximal tapered region 176 may be bonded on distal segment 137 of tube 136 or extend over bend 138 onto the distal end portion of proximal segment 139 of tube 136. Extension of the proximal neck 178 onto bend 138 and proximal segment 139 allows a greater length of the working diameter, i.e., center region 174, to be on distal segment 137 of tube 136.
A first step of the method of the invention is shown in
The luer lock 144 on proximal end 142 of balloon catheter 130 connects to the distal end 110 of tube 112 of the inflation device, which supplies fluid under pressure. As seen in
An alternative embodiment of the balloon catheter of the invention is shown in
As shown in
It should be understood that the foregoing description of the invention is intended merely to be illustrative and other modifications, embodiments, and equivalents may be apparent to those skilled in the art without departing from the spirit and scope of the invention.