Patent Application
20150057648
The present invention relates to a medical device and method for treating blood vessels, and more particularly to a laser treatment device and method for causing closure of varicose veins.
Veins are thin-walled and contain one-way valves that control blood flow. Normally, the valves open to allow blood to flow into the deeper veins and close to prevent back-flow into the superficial veins. When the valves are malfunctioning or only partially functioning, however, they no longer prevent the back-flow of blood into the superficial veins. As a result, venous pressure builds at the site of the faulty valves. Because the veins are thin walled and not able to withstand the increased pressure, they become what are known as varicose veins which are veins that are dilated, tortuous or engorged.
In particular, varicose veins of the lower extremities are one of the most common medical conditions of the adult population. Symptoms include discomfort, aching of the legs, itching, cosmetic deformities, and swelling. If let untreated, varicose veins may cause medical complications such as bleeding, phlebitis, ulcerations, thrombi and lipodermatosclerosis.
Traditional treatments for varicosities include both temporary and permanent techniques. Temporary treatments involve use of compression stockings and elevation of the diseased extremities. While providing temporary relief of symptoms, these techniques do not correct the underlying cause that is the faulty valves. Permanent treatments include surgical excision of the diseased segments, ambulatory phlebectomy, and occlusion of the vein through chemical or thermal ablation means.
Surgical excision requires general anesthesia and a long recovery period. Even with its high clinical success rate, surgical excision is rapidly becoming an outmoded technique due to the high costs of treatment and complication risks from surgery. Ambulatory phlebectomy involves avulsion of the varicose vein segment using multiple stab incisions through the skin. The procedure is done on an outpatient basis, but is still relatively expensive due to the length of time required to perform the procedure.
Chemical occlusion, also known as sclerotherapy, is an in-office procedure involving the injection of an irritant chemical into the vein. The chemical acts upon the inner lining of the vein walls causing them to occlude and block blood flow. Although a popular treatment option, complications can be severe including skin ulceration, anaphylactic reactions and permanent skin staining. Treatment is limited to veins of a particular size range. In addition, there is a relatively high recurrence rate due to vessel recanalization.
The use of embolic adhesives is also becoming more popular for treatment of varicose veins. Complications may include revascularization or incomplete vein closure that requires additional follow-up treatments and unwanted migration of the embolic adhesive.
Thermal ablation treatments, such as radiofrequency or laser energy, are becoming the most typical treatment for varicose veins. Endovascular laser therapy is a relatively new treatment technique for venous reflux diseases. Most prior art methods for laser ablation deliver the laser energy by a flexible optical fiber that is percutaneously inserted into the diseased vein prior to energy delivery. An introducer catheter or sheath is typically first inserted into the saphenous vein at a distal location and advanced to within a few centimeters of the saphenous-femoral junction of the great saphenous vein. Once the sheath is properly positioned, a flexible optical fiber is inserted into the lumen of the sheath and advanced until the fiber tip is near the sheath tip but still protected within the sheath lumen.
Known methods of thermal ablation using laser energy to treat varicose veins typically use with wavelengths between 810-1470 nm and targets absorption by the hemoglobin and/or water in the blood. As the hemoglobin and/or water in blood begin to rapidly heat as a result of energy absorption this creates a “thermal heat zone” or “heat bubble” inside the vessel. The “thermal heat zone” or “heat bubble” commonly leads to radiant or transient heating of the target zone, usually the inner cell lining of the varicose vein, and additionally non-target, healthy tissue surrounding the diseased vessel. One problem with radiant or transient heating is non-target tissue surrounding diseased vein wall, specifically the vein fascia containing nerves, may absorb the heat energy causing tissue temperature to rise above the pain and cell damage threshold of 45-50 degrees Celsius. This high absorption of energy by non-target tissue in turn causes unwanted symptoms in the patient, including vessel perforation, bruising, nerve damage, skin burns, patient pain, and general discomfort during and after treatment. To limit such symptoms tumescent injections are used prior to treatment.
Tumescent injections, typically a fluid mixture of lidocaine and saline with or without epinephrine, are administered along the entire length of the great saphenous vein using ultrasonic guidance and the markings previously mapped out on the skin surface. The typical tumescent injection process is time consuming and may take up to 30 minutes to complete. The tumescent injections perform several functions, including pain relief; acting as a thermal barrier between the vein wall and surrounding tissue, and a compressive force to reduce the vein diameter providing better contact with the ablation device. The anesthesia inhibits pain caused from application of laser energy at higher wavelengths to the vein resulting in tissue temperatures to rise above the pain and cell damage threshold of 45-50 degrees Celsius. The tumescent injection also provides a barrier between the vessel and the adjacent tissue and nerve structures, which restricts some of the heat damage to within the vessel. However, this barrier does not prevent all non-target tissue damage. As described in more detail below, an object of the current invention is to eliminate the need for tumescent injections. Further, patients can still experience pain and discomfort from undergoing endovenous laser treatment, especially if the tumescent administered is insufficient. Lastly, the requirement of tumescent anesthesia adds to the economic cost of the overall procedure.
With some of the prior art treatment methods, contact between the energy-emitting face of the treatment device and the inner wall of the varicose vein is recommended to ensure complete collapse of the diseased vessel. For example, U.S. Pat. No. 6,398,777, issued to Navarro at al, teaches either the means of applying pressure over the laser tip or emptying the vessel of blood to ensure that there is contact between the vessel wall and the fiber tip. One problem with direct contact between the laser fiber tip and the inner wall of the vessel is that it can result in vessel perforation and extravasation of blood into the perivascular tissue. This problem is documented in numerous scientific articles including “Endovenous Treatment of the Greater Saphenous Vein with a 940-nm Diode Laser: Thrombotic Occlusion After Endoluminal Thermal Damage By Laser-Generated Steam Bubble” by T. M. Proebstle, MD, in Journal of Vascular Surgery, Vol. 35, pp. 729-736 (April, 2002), and “Thermal Damage of the Inner Vein Wall During Endovenous Laser Treatment: Key Role of Energy Absorption by Intravascular Blood” by T. M. Proebstle, MD, in Dermatol Surg, Vol 28, pp. 596-600 (2002), both of which are incorporated herein by reference. When the fiber contacts the vessel wall during treatment, intense direct laser energy is delivered to the vessel wall. Conversely, by preventing direct contact between fiber and vein wall the energy is delivered to the vessel wall by indirect or radiant thermal energy from the gas bubbles caused by heating of the blood. Laser energy in direct contact with the vessel wall causes the vein to perforate at the contact point and surrounding area. Blood escapes through these perforations into the perivascular tissue, resulting in post-treatment bruising and associated discomfort.
Another problem created by the prior art methods involving contact between the fiber tip and vessel wall is that inadequate energy is delivered to the non-contact segments of the diseased vein. Inadequately heated vein tissue may not occlude, necrose or collapse, resulting in incomplete treatment.
Additionally, most conventional endovenous laser treatments use forward firing lasers which require high power densities to boil or heat the blood, creating bubbles which are necessary for 360 degree circumferential treatment of the targeted vein. High power densities can cause perforations, bruising, nerve damage, thermal damage to non-targeted tissue and other complications causing the patient additional pain. High power densities also cause charring of blood on the fiber tip.
Therefore, it would be desirable to provide an endovascular treatment device and method that applies lower power density energy directly to the tissue lining the vessel wall which can be uniformly applied to the vessel while avoiding thermal damage to non-targeted tissue.
It is also desirable to provide an endovascular treatment device and method which protects the optical fiber fom direct contact with the inner wall of vessel during the emission of laser energy to ensure consistent thermal heating across the entire vessel circumference thus avoiding vessel perforation and/or incomplete vessel collapse.
It is another purpose to provide and endovascular treatment which eliminates the need for tumescent anesthesia thus avoiding the time, pain and cost associated with the administration of tumescent.
It is another purpose to provide an endovascular treatment device and method which decreases peak temperatures at the working end of the fiber during the emission of laser energy thus avoiding the possibility of fiber damage and/or breakage due to heat stress caused by thermal runaway.
It is yet another purpose to provide an endovascular treatment device and method which is fast, effective and low in cost enabling the use of existing laser generator capital equipment.
Various other purposes and embodiments of the present invention will become apparent to those skilled in the art as more detailed description is set forth below. Without limiting the scope of the invention, a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention.
According to one aspect of the present invention, an endovascular laser treatment device for causing closure of a blood vessel is provided. The treatment device uses an optical fiber having a core through which a laser light travels and is adapted to be inserted into a blood vessel. A cladding layer is arranged around the core such that the laser energy is maintained within the core. The fiber core may be etched, scored, cut, or otherwise abrasively altered such that slits or grooves are placed into the fiber core. At a distal end portion of the device, the cladding layer may have slits, holes, or openings to expose the core. The power density of the laser energy escaping through the etching of the core and slits of the cladding may be controlled by the variable pitch or surface area of the etches and slits along the ablation zone. It is an object of this invention to provide an energy device capable of 360 degree, side, radial, or circumferential thermal ablation of the blood vessel. The distal end portion of the device may be coaxially surrounded by a sleeve, diffusor, or spacer which aids in the emission of the laser energy as it passes through the slits.
As described in more detail below, the energy delivery device may provide substantially lower power density emission, as compared to traditional forward firing energy deliver devices currently known in the art. The reduced power density emission is accomplished by increasing the surface area of exposed fiber core through which laser energy may be emitted. The exposed surface area, or ablation zone, is created by removing the cladding and optionally a portion of the core, in a pattern of etches or slits near the distal portion of the fiber. The pattern may include etches which are angled relative to the longitudinal axis of the device and which vary in pitch, width and/or spacing. The reduced power density lowers peak temperatures in the blood vessel and advantageously prevents thermal runaway, unwanted radiate heating to healthy tissue, and device damage. The reduction in power density also reduces the possibility of vessel perforations, prevents bruising, post-operative pain and other clinical complications.
In another embodiment of the invention, the distal end portion is further coaxially surrounded by a spacer. The spacer may take the form of an expandable member, such as a balloon or arms, a non-expandable member, such as a diffuser cap, or another spacer type element that is intended to keep the ablation zone of the fiber from direct contact with the vein wall. If the spacer is an expandable balloon this may prevent the fiber from coming into direct contact with the blood vessel and aids in the emission of laser energy to evenly treat the vessel wall. The balloon spacer and fiber embodiment includes a dual lumen outer shaft having an inflation/deflation lumen and a lumen sized for passage of the fiber.
A method for causing closure of a blood vessel is provided. The method involves inserting into a blood vessel an optical fiber having etches in the fiber core and slits or removed cladding layer at a distal portion of the device. Advantageously, the etching and slits enable a controlled power density emission along the ablation zone at the distal end of the fiber. The power density can be controlled so that the modality of treatment is not radiant heating, as currently used in the art by both laser and RF devices, but rather direct and controlled heating of the inner layer of endothelial cells lining the vein wall. The controlled heating of the inner layer of endothelial cells lining the vein wall reduces the possibility of vessel wall perforations and bruising. Therefore, this method may not require the administration of tumescent anesthesia before the procedure.
A method for causing closure of a blood vessel using a balloon spacer is also provided. In this embodiment, the distal end portion is also surrounded by a balloon, which, when in an inflated state, is in contact with the vessel wall. An outer shaft is inserted into the blood vessel, the outer shaft providing an inflation/deflation lumen and a lumen for passage of the fiber. The inflation/deflation lumen passes a gas or liquid, including but not limited to carbon dioxide gas, to inflate the balloon once the balloon is within the treatment site. When laser energy passes through the slits, the balloon further aids in radial treatment of the blood vessel while preventing the fiber from coming in direct contact with the vessel wall. The administration of tumescent anesthesia is not required in this method.
The following descriptions and the associated drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and/or functions; it should be appreciated that different combinations of elements and/or functions can be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and/or functions than those explicitly described above are also contemplated.
A first embodiment of the present invention is shown in
As known in the art, cladding 10 is intended to prevent light waves from escaping or being emitted from the core 5. Light energy travels in the path of least resistance. As light waves travel down the core 5 and encounter the etching of the core 5 and slits 15 of the cladding 10 the waves will begin to escape through the grooves and lists and be emitted into the surrounding vessel. The majority of the light energy will be delivered from the radial energy emitting section 4 because this section of the fiber has the most proximal exposed core surface area which permits light energy to pass through. However, depending on the power of the laser energy and the path of the light waves it is possible that a small percentage of light energy may also be emitted from the distal tip 19, as shown and described in more detail below. The light escaping from the distal tip 19 is not intended to have the power density sufficient to ablate tissue. Rather it is merely the remaining light energy—which will typically be around less than 5% of the overall light energy—that has not escaped along the radial energy emitting section 4.
In one exemplary aspect, the fiber may be a 600 micron fiber, the core 5 may be about 0.600 mm+/−0.010 mm in diameter and the thin cladding layer 10 may have 0.030 mm+0.005/−0.010 mm outer diameter. In another aspect, the fiber may be a 400 micron fiber, the core 5 having a 0.400 mm+/−0.010 mm diameter and a cladding of 0.030 mm+0.005/−0.010 mm. The fiber 3 may be comprised of a silica based core 5 and a polymer cladding layer 10 (e.g., fluoropolymer). In another aspect, the optical fiber 3 may be comprised of a glass core 5 and a glass (e.g., doped silica) cladding layer 10. For this embodiment, the outer surface of the cladding layer 10 and inner surface of the sleeve 17 may have an interference fit.
Referring to
Referring to
Referring now to
After the grooves 14 have been etched into the core 5, an outer cap 16, which may be made from glass or fused silica similar to the sleeve described above, is placed over the core 5 and attached to the jacket 9 using an adhesive or other known method in the art. The outer cap 16 gives the fiber 3 a convex distal tip 19. This convex shaped tip 19 helps ease the advancement of the fiber. The outer cap 16 is sized such that there is a space between the outer cap 16 and core 5 creating an air gap 23 around the distal end of core 5. The light energy remains inside the fiber core 5 as a result of the cladding layer 10 and the air gap 23 which acts as an additional cladding layer only for the section of core 5 that does not have any grooves 14. The light energy remains inside the fiber core 10 as a result of the cladding layer 10 and the air gap 23 which acts as an additional cladding layer.
The air gap 23 will be present and fill this void as seen in
The outer cap 16 may also has concave 27 shape along its inner wall at its distal end. The inner wall concave shape 27 may facilitate reflection of any remaining forward emitting light back through the core 5. As the laser energy travels down the fiber 3 toward the distal tip 19, the small percentage of forward firing light energy will reach the concave shape 27 and reflect the light back towards the core 5 and thereby reduce the amount of light passing through the distal tip 19 of the outer cap 16.
It is an advantage of this invention that the power density of the laser energy emitted along the radial energy emitting section 4 can be precisely controlled using variable pitches of the grooves 14. It is intended that this device will have a lower overall power density that what is currently used in forward firing lasers in the art but still have enough power density to cause thermal death to the inner cell wall of the target vein. The purpose of lowering the overall power density is to prevent unwanted vessel wall perforations or unwanted radiant heating that damages healthy tissue surrounding the target vessel. Currently tumescent anesthesia is used in part to act as a heat barrier between the energy device and the healthy surrounding tissue to decrease this unwanted radiant heating of non-targeted tissue. This device may solve the problem of unwanted radiant heating and not require the use of tumescent by controlling the amount of power density and light escaping the fiber along the radial energy emitting section 4.
By controlling the groove 14 pitch, groove size, groove 14 depth, groove 14 surface area and number of the grooves 14 along the radial energy emitting section 4 it will be possible to control and/or customize the power density of the emitted light energy along the entire length of the radial energy emitting section 4. Light energy travels in the path of least resistance so the amount of energy that is released along the radial energy emitting section 4 through the proximal edge 24 of the radial energy emitting section 4 is generally greater than the energy being released at the distal edge of the slits 26, for any given uniform slit pattern. In other words, there will be less available light energy to escape through the grooves 14 closer to the distal edge 26 of the radial energy emitting section 4. By varying the spacing, pitch, and other slit pattern characteristics, the energy emitted along the length of the emitting section 4 can be controlled. The proximal edge 24 of the radial energy emitting section 4 has grooves 14 that are spaced apart and few in number. As the groove 14 pitch moves towards the distal edge 26 the grooves 14 and pitch will become more numerous and closer together with a steeper pitch. The reason for increasing number of grooves 14 towards the distal edge 26 is to allow the maximum available light energy to escape in an effort to equalize the amount of light energy escaping along the radial energy emitting section 4. It is an intention of this device that the power density along the length of the radial energy emitting section 4 will be equal and sufficient enough to generate heat in the range of the 45-50 C at the vessel wall, the cell death threshold, but insufficient to cause unwanted radiant heating of non-target tissue, and thereby eliminating or minimizing the need for tumescent anesthesia.
The grooves 14 may be configured in any configuration stated above, but in this embodiment they are helical and have a groove pattern length 15A of approximately up to 15 mm. Furthermore, the groove pattern length 15A is comprised of a first or proximal zone 31, a second or intermediate zone 32, and a third or distal zone 33. The three zones preferably divide the groove length 15A into three equal sections. The zones are created to release a uniform radial band of laser energy. Therefore the grooves 14 will be configured so that the energy output of the first zone will equal the energy output of the second zone which will equal the energy output of the third zone 33. As seen in
The laser generator may generate up to 10 Watts of laser energy, In one embodiment using 5 Watts of power about less than 0.5 Watts of the laser energy will be emitted from the distal tip 19 which results in approximately 4.5 Watts of laser energy that will uniformly and radially be emitted from the radial energy emitting section 4. However, if desired, the amount of laser energy that is released out of the distal tip 19 can be increased by removing the concave distal end 27 from the outer cap 16, changing the angle of the reflective surface 27 or by changing the configuration of the grooves 14.
As shown in
Referring to
In yet another patter (not shown), it may be possible to have multiple radial energy emitting sections along the length of the device. For such an embodiment sections of the cladding layer may be removed and the exposed core may have grooves etched in any of the patters previously described. The advantage of having multiple radial energy emitting sections along the length of the device is that the treatment time may be reduced because the amount of treatment zones that can have energy delivered will increase.
As seen in
As shown in
As shown in
Referring to an alternative embodiment as shown in
The spacer 120 of this embodiment may be a balloon and may be made out of PTFE, latex or other similar material well-known in the art to make medical grade balloons. The spacer 120 is comprised of a body 122, a distal tapering cone 126, a proximal tapering cone 121, and a distal neck 123. In the deployed state, an outer wall of the spacer 120A (
As used herein, the outer shaft 34 can be a sheath, dilator or any other tubular device designed to aid in insertion and advancement of the optical fiber 3 through a blood vessel. The homeostasis valve 35 is a passive one-way valve that prevents the backflow of blood from the through-lumen 36 while simultaneously allowing the introduction of fibers, guidewires, and other interventional device to the outer shaft 34. The valve 35 is located within the lumen 36 of the hub 30. The valve 35 is made of elastomeric material such as a PTFE or silicone, as commonly found in the art. The valve 35 opens to allow insertion of the fiber 3 and then seals around the inserted fiber 3. However, the valve 35 does not open in response to pressure from the distal side of the device in order to prevent back-flow of blood or other fluids. The valve 35 also prevents air from entering the outer shaft 34.
The stopcock 40 and side arm tubing 38 provide multiple fluid/gas paths for administering optional procedural fluids and gases during a treatment session as described in more detail below. The stopcock 40 may be a three-way valve with a small handle (not shown) that can be moved to alter the fluid/gas path. The position of the handle controls the active fluid/gas path by shutting off the flow from one or both ports of the stopcock 40.
The fiber 3 runs coaxially within the through-lumen 36 of the outer shaft 34. During manufacture, the fiber is permanently bonded to the hub 30 using an adhesive or other known technique. Advantageously, the adhesive secures the fiber 3 to the hub 30 so that there can be no independent movement of the fiber 3 relative to the outer shaft 34 during use. When the fiber 3 is inserted through the outer shaft 34 and fiber 3 is bonded to the hub 30, the laser treatment device is in a locked operating position. In that operating position, the fiber tip 19 extends past the distal tip 37 of the outer shaft 34 by a set amount to expose the distal end section 12. The tip 37 ends within the balloon spacer 120 so that it allows carbon dioxide gas to pass through the inflation/deflation lumen 115 from the side-arm lumen 38 where the administration of the carbon dioxide gas is controlled by the stopcock 40.
Referring to
The outer shaft 34 may be a dual lumen catheter having an inflation/deflation lumen 115 and a second lumen sufficient for passage of the fiber 3 as shown in
As shown in
Methods of using the optical fiber device for endovenous treatment of varicose veins and other vascular disorders will now be described with reference to
A micropuncture sheath/dilator assembly is then introduced into the vein over the guidewire. A micropuncture sheath dilator set, also referred to as an introducer set, is a commonly used medical kit, for accessing a vessel through a percutaneous puncture. The micropuncture sheath set includes a short sheath with internal dilator, typically 5-10 cm in length. This length is sufficient to provide a pathway through the skin and overlying tissue into the vessel, but not long enough to reach distal treatment sites. Once the vein has been accessed using the micropuncture sheath/dilator set, the dilator and 0.018 inch guidewire are removed, leaving only the micropuncture introducer sheath in place within the vein. A 0.035 inch guidewire is then introduced through the introducer sheath into the vein. The guidewire is advanced through the vein until its tip is positioned near the sapheno-femoral junction or other starting location within the vein.
After removing the micropuncture sheath, a treatment sheath/dilator set is advanced over the 0.035 inch guidewire until its tip is positioned near the sapheno-femoral junction or other reflux point. Unlike the micropuncture introducer sheath, the treatment sheath is of sufficient length to reach the location within the vessel where the laser treatment will begin, typically the sapheno-femoral junction. Typical treatment sheath lengths are 45 and 65 cm. Once the treatment sheath/dilator set is correctly positioned within the vessel, the dilator component and guidewire are removed from the treatment sheath.
The optical fiber assembly 1 is then inserted into the treatment sheath lumen and advanced until the fiber assembly distal end is flush with the distal tip of the treatment sheath. A treatment sheath/dilator set as described in U.S. Pat. No. 7,458,967, incorporated herein by reference, may be used to correctly position the protected fiber tip with spacer assembly 1 of the current invention within the vessel. The treatment sheath is retracted a set distance to expose the fiber tip, typically 1 to 2 cm. If the fiber assembly has a connector lock as described in U.S. Pat. No. 7,033,347, also incorporated herein by reference, the treatment sheath and fiber assembly are locked together to maintain the 1 to 2 cm fiber distal end exposure during pullback, as seen in
At this time, prior art methods require the administration of tumescent anesthesia along the vein, which can take up to 30 minutes. The present invention emits laser energy radially, directing the energy to the vessel wall and as a result, only requires a low power density, which eliminates perforations and thermal damage to surrounding tissue and nerves. Therefore the present invention may not require the administration of tumescent anesthesia. However, if tumescent is required then the physician may inject at this time.
Once device 1 has in proper treatment position relative to the sapheno-femoral junction, the laser generator 2 is turned on and the laser light enters the optical fiber 3 from its proximal end via the proximal connection to the laser generator 7. While the laser light is emitting laser light through the distal end section 4, the treatment sheath/fiber assembly is withdrawn through the vessel at a variable rate, ranging at 50-80 J/cm for 2-3 millimeters per second, and also depending on the size of the vessel being treated. Alternatively, in another embodiment of the method the physician may withdraw the sheath/fiber assembly in a pulsed manner. The laser energy travels along the optical fiber 3 through the slits 15 and into the vein lumen where the laser energy is uniformly delivered radially to heat the vein wall, thus damaging the vein wall tissue, causing cell necrosis and ultimately causing collapse/occlusion of the vessel. Forward firing of the lasers which require high power densities to boil or heat the blood, creating bubbles which are necessary for 360 degree circumferential treatment of the targeted vein. High power densities can cause perforations, bruising, nerve damage, thermal damage to non-targeted tissue and other complications causing the patient additional pain. High power densities also cause charring of blood on the fiber tip. Advantageously, the method of using this invention does not require high power density in a forward firing direction and therefore these risks are diminished or removed from the treatment.
The outer jacket 9 of fiber 3 may include visual markings/markers. Markings are used by the physician to provide a visual indication of insertion depth, tip position and speed at which the device is withdrawn through the vessel during delivery of laser energy. The markings may be numbered to provide the physician with an indication as to distance from the distal end section of the fiber 12 to the access site during pullback. The markings may be positioned around the entire circumference of the fiber shaft or may cover only a portion of the shaft circumference.
Once the targeted tissue is treated, the laser generator 2 is turned off. The procedure for treating the varicose vein is considered to be complete when the desired length of the great saphenous vein has been exposed to laser energy. Normally, the laser generator is turned off when the fiber tip 19 is approximately 3 centimeters from the access site. The combined sheath/endovascular laser treatment device 1 is then removed from the body as a single unit.
Prior art methods provide a cladding that does not have slits therethrough and thus delivers laser energy via an emitting face at the distal tip of the fiber which causes charring and blood build-up on the tip. By emitting laser energy through the slits 15, the device provides radial treatment and reduces the laser energy emitted out of the distal tip 19. Because minimal energy is emitted from the distal tip 19, treatment using the present invention does not result in charring.
Methods of using the optical fiber device with balloon spacer for endovenous treatment of varicose veins and other vascular disorders will now be described with reference to
In this embodiment, markings can be placed on the catheter 34 instead of jacket 9, as in the previous embodiment so that the physician can measure the rate at which the fiber 3 is being pulled back. The catheter 34/fiber 3 assembly is slowly withdrawn together through the vein. The connection between the fiber connector 31 and hub connector 32 ensures that the distal end section 4 remains exposed beyond the catheter tip 37 by the recommended length for the entire duration of the treatment procedure. Once treatment is complete, the expandable member 120 is deflated and device is removed. This embodiment has the ability to inflate and/or deflate as the device is moved through the vessel to accommodate varying diameter vein segments.
As may be recognized by those of ordinary skill in the pertinent art, blood vessels other than the great saphenous vein and other hollow anatomical structures can be treated using the device and/or methods of the invention disclosed herein.
The above disclosure is intended to be illustrative and not exhaustive. This description will suggest many modifications, variations, and alternatives that may be made by those of ordinary skill in this art without departing from the scope of the invention. Those familiar with the art may recognize other equivalents to the specific embodiments described herein. Accordingly, the scope of the invention is not limited to the foregoing specification.
This application claims priority under 35 U.S.C. 119(e) to U.S. Provisional Application No. 61/867,627, filed Aug. 20, 2013, which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61867627 | Aug 2013 | US |
