System for enhancing visibility in the epidural space

Information

  • Patent Grant
  • 6925323
  • Patent Number
    6,925,323
  • Date Filed
    Monday, August 12, 2002
    22 years ago
  • Date Issued
    Tuesday, August 2, 2005
    19 years ago
  • Inventors
  • Examiners
    • Lucchesi; Nicholas D.
    • Rodriguez; Cris L.
    Agents
    • Bracewell & Patterson LLP
    • Whittle; Jeffrey S.
Abstract
A system for enhancing visibility in the epidural space is provided that improves visibility in the epidural space of a patient for more effectively conducting therapeutic surgery therein. The method includes the steps of distending a portion of the epidural space of a patient by filling the portion of the epidural space with a fluid supplied from a catheter and positioning a portion of an optical scope in the distended portion of the epidural space by inserting the optical scope through the same catheter that supplies the distending fluid to thereby provide a visual image of the epidural space.
Description
FIELD OF THE INVENTION

This invention relates to surgical methods, and more particularly to methods of epidural surgery in and around the epidural space.


BACKGROUND OF THE INVENTION

Back pain, and particularly lower back pain, is a major expense to society and is one of the most common disabling problems of those of working age. Injuries to the back vary from herniated disks of the spine to muscle strains and nerve damage. In the back or posterior end of the human body, the epidural space is potential space located in and extending the length of the spine. The epidural space is defined along one edge or side by the dura mater which surrounds the spinal cord. The epidural space is further defined along a second edge or side by the periosteum of the bony vertebrae or by the ligamentum-flavum at the vertebral interspaces. Along the interior surface of the ligamentum-flavum lies the venus plexus, a complex configuration of veins. The epidural space contains fat, connective tissue, blood vessels, lymphatic vessels, nerve fibers, and other structures. Various lesions, cystical masses, and nerve damage can occur in and around the epidural space which causes various back problems for the human body.


Although applying anesthesia to the epidural space has been known for procedures such as child birth or the like, the anatomy of the epidural space and related structures has not been fully investigated. Conventionally, the insertion of a catheter, fluid introducer, or the like for inducing spinal anesthesia directly into the subarachnoid space of the spinal column, such as seen in U.S. Pat. No. 5,232,442 by Johnson, et al. entitled “Method And Apparatus For Inducing Anesthesia”, has been through fluoroscopic or radiographic observation. Fluoroscopic observation techniques have also been used to try to locate the various sources of problems associated with back pain such as seen in U.S. Pat. No. 5,215,105 by Kizelshteyn, et al. entitled “Method Of Treating Epidural Lesions”. The fluoroscopic techniques are helpful for general guidance of instruments or other devices, but fail to give the physician or other medical personnel a detailed picture of structures within vessels or cavities, such as the epidural space, and therefore are limited in identifying the source of back pain problems.


Also, endoscopes have been used whereby internal areas or organs within a body vessel or cavity may be observed by inserting an elongated insertable part of the endoscope through a tube or sleeve inserted into a body vessel or cavity, or directly into the body vessel or cavity itself, such as seen in U.S. Pat. No. 5,195,541 by Obenchain entitled “Method Of Performing Laparoscopic Lumbar Discectomy”. An endoscope, as used herein, is an instrument for examining the interior of a bodily canal or hollow organ. A catheter, on the other hand, is a tube inserted into a bodily channel, such as a vein, to maintain an opening to a body vessel or cavity. These endoscopes, however, are relatively large with respect to a catheter and, therefore, do not cooperate with a catheter for performing delicate surgery such as the type surrounding the back or spinal column.


Further, fiber optic scopes or fiberscopes have been used for various types of surgery such as surrounding the heart. These fiberscopes often are inserted into a vein or an artery for viewing blockage or the like within the vein or artery. The epidural space, however, has not fully been explored using visual techniques because the epidural space, as described above, does not take the form of a vein or artery. Because the epidural space collapses around an instrument or device inserted therein such as a catheter, an endoscope, a fiberscope, or a cutting tool, the space has not been considered for optical scope viewing or for performing many types of epidural surgical procedures.


Therefore, there is still a need for a method of epidural surgery that allows a physician to effectively enter the epidural space of a patient, visually observe and document a problem area which could be the source of back pain in the patient, and therapeutically treat the problem area in or around the epidural space in a minimal amount of time and with minimal amount of cutting and other potential damage to the patient during surgery.


SUMMARY OF THE INVENTION

The present invention provides a method of epidural surgery that improves visibility in the epidural space of a patient for more effectively conducting therapeutic surgery therein. The method of epidural surgery involves distending a portion of the epidural space by filling the portion of the epidural space with a fluid supplied from a catheter positioned in the epidural space and positioning a portion of an optical scope in the distended portion of the epidural space by inserting the optical scope through the catheter to thereby provide a visual image of the epidural space. The method of epidural surgery also allows a physician, or other medical personnel, to control and manipulate the catheter and an imaging source while simultaneously using surgical tools, such as fiberoptic scopes or the like, and fluids needed for medical operations to thereby allow the physician to positionally locate, isolate, and view problem areas within the epidural space. Because the method of epidural surgery minimizes cutting and other potential damage to the patient during surgery, the invention provides a method of epidural surgery that often can be performed as an outpatient procedure.





BRIEF DESCRIPTION OF THE DRAWINGS

Some of the objects and advantages of the present invention having been stated, others will become apparent as the description proceeds when taken in conjunction with the accompanying drawings, in which:



FIG. 1 is a fragmentary skeletal view of a human body illustrating spinal column regions thereof;



FIG. 2 is a fragmentary view of a spinal column illustrating the position of the epidural space therein;



FIG. 3 is an elevational plan view of a surgical operation on a patient having a catheter positioned through an opening in the sacrum region and into the epidural space by a physician for therapeutic treatment of a problem area according to a first embodiment of the present invention;



FIG. 4 is perspective view of an imaging apparatus for the methods according to the present invention;



FIG. 5 is a side elevational view of a catheter having a fiberscope inserted therein for the methods according to the present invention;



FIG. 6 is a perspective view of a catheter having a fiberscope inserted therein for the methods according to the present invention;



FIG. 7 is fragmentary top elevational view of a catheter for the methods according to the present invention;



FIG. 8 is an enlarged cross-sectional view of a first embodiment of a catheter taken along line 88 of FIG. 7 for the methods according to the present invention;



FIG. 9 is an enlarged cross-sectional view of a second embodiment of a catheter taken along line 88 of FIG. 7 for the methods according to the present invention;



FIG. 10 is an enlarged distal end plan view of a catheter taken from a distal end thereof for the methods according to the present invention;



FIG. 11 is enlarged fragmentary top plan view of a distal end of a catheter and having phantom lines therein illustrating the positioning of the multiple lumens within the catheter for the methods according to the present invention;



FIG. 12 is enlarged fragmentary side plan view of a distal end of a catheter for the methods according to the present invention;



FIG. 13 is a block diagram of a method of epidural surgery according to a first embodiment of the present invention; and



FIG. 14 is a block diagram of a method of epidural surgery according to a second embodiment of the present invention.





DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The present invention now will be described more fully hereinafter with reference to the accompanying drawings in which a preferred embodiment of the invention is shown. Like numbers refer to like elements throughout.


In the back region or posterior end of the human body, as best illustrated in FIGS. 1 and 2, the epidural space 20 is potential space located in and extending the length of the spine 18. As illustrated in the fragmentary view of a spinal region 18 in FIG. 2, the epidural space 20 has a generally cylindrical or crescent type shape and is defined along one edge or side by the dura mater 22 which surrounds the spinal cord 19. The epidural space is further defined along a second edge or side by the periosteum of the bony vertebrae 23 or by the ligamentum-flavum 24 at the vertebral interspaces 25. Along the interior surface of the ligamentum-flavum 24 lies the venus plexus 26, a complex configuration of veins. The epidural space 20 is a collapsible potential space that contains fat, connective tissue, blood vessels, lymphatic vessels, nerve fibers, and other structures. Various lesions, cystical masses, and nerve damage can occur in and around the epidural space which causes various back problems for the human body. For example, fibrosis ranging from soft to tougher scar tissue may form randomly or in layers and adhere to the dura mater 22 and the periosteum of the body vertebrae 20 or the ligamentum-flavum 24 which form lesions extending across the epidural space 20. These lesions can be caused by post operative scarring of nerves such as from laminectomy procedures. A ruptured, leaking, or torn disk can also cause lesions which are often the source of back pain.


The method of epidural surgery according to the present invention improves visibility in the epidural space 20, of a patient for more effectively conducting therapeutic surgery in and around the epidural space 20 such as applying a steroic fluid, performing a diskectomy, or disrupting a fibrotic lesion. The method of epidural surgery according to the present invention involves distending a portion of the epidural space 20 by filling the portion of the epidural space 20 with a fluid, preferably a liquid such as a normal saline solution, supplied from a catheter 30 positioned in the epidural space 20. As best shown in FIGS. 3-6, a portion of an optical scope 60 is positioned in the distended portion of the epidural space 20 by inserting the optical scope 60 through the catheter 30 to thereby provide a visual image 100 of the epidural space 20.


According to first and second embodiments of the present invention, the catheter 30 may be one of the numerous types of catheters known to those skilled in the art, but preferably is a multi-lumen, steerable catheter 30 as best illustrated with reference to FIGS. 5-12. The multi-lumen, steerable catheter 30 preferably has a multiple durometer tube portion 40 extending outwardly from a handle portion 35 such as disclosed and described in copending U.S. patent applications Ser. No. 07/908,403 filed on Jul. 6, 1992 and Ser. No. 07/970,490 filed on Nov. 2, 1992 which are hereby incorporated herein by reference. The optical scope 60 is preferably an 0.88 millimeter (mm) fiberscope, known to those skilled in the art, that may be inserted through a lumen 41 of the steerable catheter 30, and preferably through a fiberoptic sheath 61 as shown in FIG. 5 and have a portion 62 thereof extend into the epidural space 20. The fiberscope 60 preferably communicates with an imaging apparatus such as disclosed and described in copending U.S. patent application Ser. No. 07/963,431 filed on Oct. 12, 1992 which is also hereby incorporated herein by reference. As such, further details of the steerable catheter 30, the optical scope 60, and the imaging apparatus 80 will not be discussed except in relation to the operation thereof for the methods of epidural surgery according to the present invention.


By providing the combination of the steerable catheter 30, the fiberscope 60, and the imaging apparatus 80, as illustrated in the elevational plan view of FIG. 3, a physician 17, or other medical personnel, can control and manipulate the catheter 30 and the imaging source 82 of the imaging apparatus 80 while simultaneously using surgical tools, such as cutting instruments or the like, and fluids needed for medical operations to thereby allow the physician to positionally locate, isolate, and view problem areas on a television monitor 84, i.e., cathode ray tube display device, within the epidural space 20. The imaging apparatus 80 enables the physician to not only observe the visual image 100 of the distended portion of the epidural space 20, but also provides a means for recording and documenting the problem area such as the video cassette recording 86 mounted below the imaging source 82 and television monitor 84 on the portable stand 88. Since the steerable catheter 30 is preferably quite flexible and maneuverable within the epidural space 20, as best shown in FIGS. 6 and 7, the method also provides less radical interspinal surgical operations because problem areas can more effectively be observed and accessed with the optical scope 60 and steerable catheter 30 combination.


Because the imaging apparatus 80 is mounted on a stand 88 having wheels 87, as best shown in FIGS. 5, the physician 17, and other medical personnel, can position the apparatus 80 close to the operation site. The control panel 83 and imaging source 82 of the imaging apparatus 80 provides image 100 adjustments, focus, and magnification to assist in viewing the epidural space 20 and the problem area when the portion of the epidural space 20 is distended by the liquid. It will be understood that the distended portion of the epidural space 20 to be viewed is preferably an amount of the epidural space 20 less than the entire boundaries thereof, the boundaries or peripheries being previously defined and described with reference to FIG. 3.


More particularly with reference to the block diagrams illustrated in FIGS. 13 and 14, and the elevational plan view of a surgical operation in FIG. 3, the method of epidural surgery according to the present invention includes inserting a needle through the skin of a patient 120, preferably through a sacrum region 125 (FIG. 13) or a lumbar region 135 (FIG. 14) of the patient 120, and into the epidural space 20 to thereby provide an opening from the skin into the epidural space 20 of the patient 120.


As illustrated in FIG. 1, the sacrum region 125 is at a lower end of the spinal column 18 below L-5 and adjacent the pelvic region 28. The sacrum 125 is a triangular shape bone formed generally by five fused vertebrae, i.e., sacral vertebrae, that are wedged dorsally between the two hip bones of the pelvic region 28 in this region of the human anatomy. It will also be understood by those skilled in the art that the invention is also applicable to various animals for veterinarian epidural procedures. The lumbar region 135 extends from L-1 to L-5 between the sacrum region 125 at a lower end and the thorax region (T-1 to T-12) at an upper end. The thorax region (T-1 to T-12) from an upper part 150 (T-12) lumbar region 135 to neck.


As illustrated in FIG. 13, according to a first embodiment of a method of epidural surgery 160 according to the present invention, the patient is scrubbed in the sacrum region 125, preferably in an area around the sacral canal and up to the level of T-8 (FIG. 1) with wide prep iodine, as shown by block 161. The patient 120 is draped, the physician 17 is scrubbed, and dressed in a sterile gown (FIG. 3). The entry site is prepared and a one percent (1%) Xylocaine solution is injected to create a skin wheel. The patient 120 is then sedated with Versed which is individually titrated to the patient's needs. The patient is also monitored with pulse oximetry, EKG, and a blood pressure monitor.


After the patient is scrubbed and prepared, a needle, preferably an 18-gauge Touhy needle, is used to access the sacral foramen, as shown by block 162. The ligamentum-flavum 24 (FIG. 2) is pierced and the needle tip is inserted in the sacral hiatus. Under fluoroscopic guidance, as shown by block 163, a guide wire, preferably a 0.035-inch straight tip floppy guide wire, is inserted and advanced through the needle and into the epidural space. The guide wire is preferably radiopaque and formed of stainless steel with a Teflon coating. The physician 17 then preferably fluoroscopically observes the position of the guide wire in the epidural space 20 and advances the guide wire to a spinal level where a suspected problem area within the epidural space 20 may have originated. As shown by block 164, the needle is extracted from the epidural space 20 and preferably discarded.


The catheter 30, and preferably a multi-lumen, steerable catheter, is then inserted over the guide wire and into the opening to the epidural space 20, as shown by block 165. The guide wire functions as a guidance device as the catheter 30 is advanced into the sacral hiatus. Because the catheter 30 is preferably a steerable catheter, the handle 35 and flexible distal end 45 ease the advancement and positioning of the catheter 30 within and around the epidural space 20. Fluid is supplied, and preferably continuously supplied, to a lumen 42 of the steerable catheter 30 to thereby distend a portion of the epidural space 20. The fluid is preferably a liquid such as a normal saline solution. A normal saline bag can be accessed with an I.V. set and coupled to a fluid pressure regulator 70, which includes a three-way stop-cock 71 or valve for fluid regulation. A 20 cubic centimeter (cc) syringe 72 is then coupled to a second port of the three-way stop-cock 71. An access port to a lumen 42 of the catheter 30 is also preferably coupled to a third port of the stop-cock 71. The fluid may also enter through tube portion 38 at a proximal end 37 at the handle portion 35 of the catheter 30 (as best shown in FIG. 6). The 20 cc syringe 72 is used first to extract all the air bubbles from the I.V. set and then fill the I.V. set with a normal-saline, liquid solution for distention of the epidural space. Twenty cc's of saline can be infused into the epidural space 20, as shown by block 166. The 20 cc's are sufficient to increase the pressure in a portion of the epidural space 20 and create a cavity in which the nerve root or other structures can be observed. The position of the steerable catheter 30 within the epidural space may also be fluoroscopically observed. The catheter 30, like the guide wire, is also preferably radiopaque. Under such circumstances, the physician can advance the steerable catheter 30 under the fluoroscopical observation to the suspected problem area.


As shown by block 167, an optical scope 60, preferably a fiber optic scope or fiberscope, is then inserted preferably within another lumen 41 of the multi-lumen, steerable catheter 30. The fiberscope 60 can enter an access port in the handle portion 35, as best shown in FIG. 6, or enter at a proximal end 37 of the handle portion 35 as shown in FIG. 3 or 4. It will also be understood that the fiberscope 60 can be inserted prior to the advancement of the catheter 30 in the epidural space 20. A portion of the optical scope 60 is advanced within the lumen 41 of the steerable catheter 30 and into the distended portion of the epidural space 20. The optical scope 60 preferably is not radiopaque and preferably will not extend into the epidural space 20 more than about one centimeter (cm). With the fluid distending a portion of the epidural space 20, the optical scope 60 can also be positioned within the distal tip 45 of catheter 30 and still view the distended portion of the epidural space 20. The optical scope 60 illuminates the distended portion of the epidural space 20 to thereby visualize and display the epidural space 20 and a problem area therein with the imaging apparatus 80, as shown by block 168. The catheter 30 can be manipulated to place the distal end 45 into an optimal position to avoid any adhesions or naturally occurring fat globules that could hinder the flow of drugs such as a steroic fluid or that could hinder positioning of instruments or devices used in surgical procedures. As shown by block 169, the catheter 30 is manipulated until the problem area such as an inflammation is recognized by its redness, increased vascularity, or other systems. The problem area is then observed and documented. As shown by block 171, a treatment is then performed to the problem area within the epidural space such as the applying of a steroic fluid to a nerve area, disrupting a fibrotic lesion, performing a diskectomy, or other types of procedures. These therapeutic treatments preferably include positioning a distal end 45 of the steerable catheter 30 adjacent the problem area within the epidural space 20 and treating the problem area within the epidural space 20 through a lumen 41 or 42 of the steerable catheter 30.


After performing the treatment, the catheter 30 is then slowly extracted and a dressing is placed at the site of entry, as shown by blocks 172, 173. The patient is observed, preferably for about two hours, then discharged, as shown by block 174. The patient's chart is completed and a one week follow-up appointment may be made.


As illustrated in FIG. 14, according to a second embodiment 180 of a method of epidural surgery of the present invention, a lumbar region 135 of the patient 120 is scrubbed and prepped, preferably in and around the L3-L4 area (FIG. 1), as shown by block 181. In this second embodiment, in contrast to the first embodiment as illustrated in FIG. 2, the patient 120 is preferably in a sitting position to spread the L1-L5 vertebrae to make access easier. It will also be understood that other sites of entry along the spinal column 18, besides the sacrum or caudal region 125 and lumbar region 135 of the patient 120, may be performed according to the present invention.


As shown by block 182, an 18-gauge Touhy needle is inserted into the interspinal space, such as between L3 and L4, using the loss of resistance technique well known to those skilled in the art. The epidural space 20 is confirmed and a guide wire, preferably a 0.035-inch straight floppy top guide wire, is inserted and advanced through the needle to the spinal level where the suspected problem area may be located in and around the epidural space 20, as shown by blocks 185, 186. The needle is then extracted (block 185) and preferably discarded.


As shown by block 187, the catheter 30 is inserted and advanced over the guide wire to the suspected problem area. The epidural space 20 is then infused with a fluid, as previously described with reference to the first embodiment, and distended (block 187). A portion of the optical scope 60 is inserted and advanced through a lumen 41 of the catheter 30 and into the distended portion of the epidural space 20, as shown by block 188. The problem area is observed and documented, and the catheter is manipulated and positioned adjacent the problem area for more effectively performing a therapeutic procedure, such as previously described (blocks 189, 191). A therapeutic procedure is then performed, also as previously described, as shown by block 192. The catheter 30 is then slowly extracted, the entry site is dressed, and the patient is observed (blocks 193-195). A follow-up visit is then scheduled and the patient discharged.


The method of the present invention thereby provides improved visualization of the epidural space and more effective treatment of problems areas therein. The method allows the physician to effectively observe and document the problem area and then determine the most effective treatment for the patient. Since the steerable catheter is preferably quite flexible and maneuverable within the epidural space, the method also provides less radical interspinal surgical operations because problem areas can more effectively be observed and accessed with the optical scope and steerable catheter combination.


In the drawings and specification, there have been disclosed typical preferred embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purposes of limitation. The invention has been described in considerable detail with specific reference to various embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the invention as described in the foregoing specification and defined in the following appended claims.

Claims
  • 1. A system for enhancing visibility in the epidural space, the system comprising: a steerable catheter having a handle portion, a tube portion connected to the handle portion and extending outwardly therefrom, and steering means connected to at least the handle portion for steering distal end portions of the tube portion; said tube portion having a plurality of lumen formed therewithin, including at least a first working lumen and a second working lumen, each of said first and second working lumens having distinct, non-coincident longitudinal axes and being separated from each other by a portion of the elongate tube portion; each of said first and second working lumens being substantially symmetrically positioned along both sides of said tube diameter; a fiber optic scope positioned to extend through the second working lumen of the steerable catheter; and said first working lumen positioned within the steerable catheter for continuously supplying fluid under pressure to the epidural space and for distending the epidural space so that the epidural space is maintained in a distended state to enhance visibility when the fiber optic scope is positioned in the second working lumen of the steerable catheter.
  • 2. A system as defined in claim 1, wherein the handle portion includes a plurality of access portions formed therein, and wherein the plurality of access portion is in fluid communication with a least each of said first and second working lumens, respectively amongst said plurality of lumen.
  • 3. A system as defined in claim 2, wherein said first working lumen includes means connected to the steerable catheter for supplying a continuous pressure to a fluid in communication with the steerable catheter to maintain fluid pressure through the catheter to the epidural space thereby ensuring a continuous flow of fluid to distend and maintain in a distended state the epidural space.
  • 4. A system as defined in claim 1, wherein the first working lumen includes means connected to the steerable catheter for maintaining the epidural space in a distended state when at least portions of said tube portion of the steerable catheter is positioned within the epidural space.
  • 5. A system as define in claim 1, wherein the system further includes a continuous pressure supplier in operable engagement with said first working lumen to supply fluid to the epidural space to thereby maintain the epidural space in a distended state to enhance visibility when the fiber optic scope is positioned in the tube portion of the steerable catheter.
  • 6. A system as defined in claim 1, wherein the system further includes a continuous pressure supplier in operable engagement with said first working lumen to supply a continuous pressure to a fluid in communication with the steerable catheter so as to maintain fluid pressure through the catheter to the epidural space thereby ensuring a continuous flow of fluid to distend and maintain in a distended state the epidural space.
  • 7. A system for enhancing visibility in the epidural space, the system comprising: a steerable catheter comprising: a handle, a tube having a tube diameter, said tube being connected to the handle and extending outwardly therefrom, the tube having a flexible distal portion and at least two lumen defining first and second working lumen extending lengthwise through the tube from the proximal end to the distal end thereof and being substantially parallel to each other, each of said first and second working lumen having distinct, non-coincident longitudinal axes, and being separated from each other by a portion of the tube, each of said first and second working lumen being substantially symmetrically positioned along both sides of said tube diameter, and a controller connected to the handle to control flexible movement of the flexible distal portion of the tube; an epidural space distender comprising a fluid pressure supply positioned to supply fluid pressure through the first working lumen to the epidural space to thereby distend the epidural space and maintain the epidural space in a distended state responsive to the fluid pressure; and an epidural space imager associated with the steerable catheter to provide visual images of the distended epidural space, the imager including a flexible fiber optic scope positioned to extend through the second working lumen of the tube, the tube being responsive to the controller and positioned to flex independently of the movement of the flexible fiber optic scope.
  • 8. A system for enhancing visibility in the epidural space as defined in claim 7, wherein the epidural space distender further comprises a fluid pressure regulator connected to the fluid pressure supplied to the epidural space at a rate sufficient to maintain the epidural space in a distended state.
  • 9. A system as defined in claim 8, wherein the fluid pressure supply of the epidural space distender comprises a pliable container in fluid communication with the first working lumen of the tube.
  • 10. A system as defined in claim 9, wherein the fluid pressure regulator comprises a stop-cock interposed between and in fluid communication with the fluid pressure supply and the first working lumen of the tube, the stop-cock having at least one access port adapted to be coupled with a syringe having a volumetric capacity of at least twenty cubic centimeters (20cc).
  • 11. A system as defined in claim 8, wherein the fluid pressure supply of the epidural space distender comprises a variable pressure fluid container having a distal end positioned to be in fluid communication with the first working lumen of the tube and a proximal end connected to the fluid pressure regulator, the fluid pressure regulator positioned to selectively change the variable fluid pressure of the container.
  • 12. A system as defined in claim 11, wherein the epidural space distender comprises a syringe.
  • 13. A system as defined in claim 7, wherein each of the first and second working lumen having a cross-sectional diameter, the cross-sectional diameter of each of the first and second working lumen being substantially coincident with the diameter of said tube.
  • 14. A system as defined in claim 13, wherein the cross-sectional diameter of the first working lumen is substantially different from the cross-sectional diameter of the second working lumen.
  • 15. A system as defined in claim 7, wherein the epidural space distender comprises a syringe.
  • 16. A system as defined in claim 15, wherein the tube connected to the handle and extending outwardly therefrom defines a first handle and wherein the epidural space distender comprises a second tube, the second tube extending outwardly from the handle, being in fluid communication with the first tube, and having a distal end connected to and in fluid communication with the syringe.
  • 17. A system as defined in claim 7, wherein the handle portion comprises a top portion, at least one side portion extending therefrom in a direction substantially perpendicular to the top portion, and a bottom portion connected to the at least one side portion, the handle further having a medial lateral extent, a distal end lateral extent, and a proximal end lateral extent, and wherein the medial lateral extent is less than both the distal end lateral extent and the proximal end lateral extent to thereby provide the handle a substantially hour-glass configuration readily held in the hand of a user.
  • 18. A steerable catheter comprising: a handle; first and second tubes each connected to the handle and extending outwardly therefrom, the first tube having a tube diameter, a flexible distal portion and at least two lumen defining first and second working lumen extending substantially parallel to each other lengthwise therein, and the second tube having at least one working lumen positioned to be in fluid communication with at least one of the working lumen of the first tube; each of said first and second working lumen having distinct, non-coincident longitudinal axes, and being separated from each other by a portion of the tube; each of said first and second working lumen being substantially symmetrically positioned along both sides of said tube diameter; and a controller connected to the handle to control flexible movement of the flexible distal portion of the first tube.
  • 19. A steerable catheter as defined in claim 18, wherein the handle has an upper portion, a side portion connected to the upper portion, and a lower portion connected to the side portion and underlying the upper portion, wherein the controller is at least partially contained within the handle and includes at least one lobe extending outwardly from the side portion of the handle such that the at least one lobe is readily accessible to a user holding the handle to thereby assist the user in controlling the flexing of the flexible distal portion of the first tube by the user moving the at least one lobe.
  • 20. A steerable catheter as defined in claim 19, wherein the controller comprises a control wheel having a peripheral portion, the at least one lobe connected to and extending outwardly from the peripheral portion of the control wheel.
RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 09/351,388 filed Jul. 13, 1999, now U.S. Pat. No. 6,470,209 which is a continuation of U.S. Ser. No. 09/066,884 filed Apr. 27, 1998, now U.S. Pat. No. 6,010,493, which is a continuation of U.S. Ser. No. 08/957,998 filed Oct. 22, 1997, now U.S. Pat. No. 5,857,996, which is a continuation of U.S. Ser. No. 08/606,084 filed Feb. 23, 1996, now abandoned, which is a continuation of U.S. Ser. No. 08/321,174 filed Oct. 11, 1994, now U.S. Pat. No. 5,496,269, which is a continuation of U.S. Ser. No. 08/129,331, filed Sep. 30, 1993, now U.S. Pat. No. 5,354,266, which is a continuation-in-part of U.S. Ser. No. 07/908,403 filed Jul. 6, 1992, now U.S. Pat. No. 5,342,299, which is a continuation-in-part of U.S. Ser. No. 07/963,431 filed Oct. 19, 1992, now U.S. Pat. No. 5,423,311, which is a continuation-in-part of U.S. Ser. No. 07/970,490 filed Nov. 2, 1992, now U.S. Pat. No. 5,399,164.

US Referenced Citations (156)
Number Name Date Kind
922985 Wappler Oct 1909 A
D202552 Rose Oct 1965 S
3470876 Barchiton Oct 1969 A
3500820 Almen Mar 1970 A
3605725 Bentov Sep 1971 A
3625200 Muller Dec 1971 A
3773034 Burns et al. Nov 1973 A
3788304 Takahashi Jan 1974 A
3831017 Auer Aug 1974 A
3892228 Mitsui Jul 1975 A
3948251 Hosono Apr 1976 A
D243115 Ziegler et al. Jan 1977 S
4273111 Tsukaya Jun 1981 A
4279245 Takagi et al. Jul 1981 A
4327723 Frankhouser May 1982 A
4344092 Miller Aug 1982 A
4353358 Emerson Oct 1982 A
4390012 Mizumoto Jun 1983 A
4413278 Feinbloom Nov 1983 A
4417886 Frankhouser et al. Nov 1983 A
4421106 Uehara Dec 1983 A
4433675 Konoshima Feb 1984 A
4475539 Konomura Oct 1984 A
4483326 Yamaka et al. Nov 1984 A
4515592 Frankhouser May 1985 A
4535773 Yoon Aug 1985 A
4539586 Danna et al. Sep 1985 A
4543090 McCoy Sep 1985 A
4545374 Jacobson Oct 1985 A
4551292 Fletcher et al. Nov 1985 A
4563181 Wijayarathna et al. Jan 1986 A
4573448 Kambin Mar 1986 A
4577621 Patel Mar 1986 A
4580551 Siegmund et al. Apr 1986 A
4587972 Morantte, Jr. May 1986 A
4589404 Barath et al. May 1986 A
4590923 Watanabe May 1986 A
4601284 Arakawa et al. Jul 1986 A
4611888 Prenovitz et al. Sep 1986 A
D286280 Holtman et al. Oct 1986 S
4625713 Hiraoka Dec 1986 A
4644960 Johans Feb 1987 A
4649904 Krauter et al. Mar 1987 A
4651202 Arakawa Mar 1987 A
4653476 Bonnet Mar 1987 A
4713057 Huttner et al. Dec 1987 A
4737142 Heckele Apr 1988 A
4745908 Wardie May 1988 A
4748969 Wardle Jun 1988 A
4750475 Yoshihashi Jun 1988 A
4753222 Morishita Jun 1988 A
4758222 McCoy Jul 1988 A
4776844 Ueda Oct 1988 A
4782819 Adair Nov 1988 A
4791912 Tashiro Dec 1988 A
4793326 Shishido Dec 1988 A
4797737 Yazawa Jan 1989 A
4799496 Hargreaves et al. Jan 1989 A
4808157 Coombs Feb 1989 A
4815450 Patel Mar 1989 A
4834710 Fleck May 1989 A
4844053 Dittrich Jul 1989 A
4853773 Hibino et al. Aug 1989 A
4867529 Utsumi et al. Sep 1989 A
4878485 Adair Nov 1989 A
4884133 Kanno et al. Nov 1989 A
4888146 Dandeneau Dec 1989 A
4890602 Hake Jan 1990 A
4893613 Hake Jan 1990 A
4901142 Ikuno et al. Feb 1990 A
4904237 Janese Feb 1990 A
4905666 Fukuda Mar 1990 A
4906230 Maloney et al. Mar 1990 A
4911148 Sosnowski et al. Mar 1990 A
4919112 Siegmund Apr 1990 A
4919653 Martinez et al. Apr 1990 A
4920413 Nakamura et al. Apr 1990 A
4924856 Noguchi May 1990 A
4930521 Metzger et al. Jun 1990 A
4933816 Hug et al. Jun 1990 A
4934340 Ebling et al. Jun 1990 A
4941455 Watanabe et al. Jul 1990 A
D310721 Beisang, III Sep 1990 S
4954129 Giuliani et al. Sep 1990 A
4968295 Neumann Nov 1990 A
4968298 Michelson Nov 1990 A
4972828 Ito Nov 1990 A
4973312 Andrew Nov 1990 A
4973329 Park et al. Nov 1990 A
4979496 Komi Dec 1990 A
4983165 Loiterman Jan 1991 A
4985022 Fearnot et al. Jan 1991 A
4989582 Sakiyama et al. Feb 1991 A
4996974 Ciarlei Mar 1991 A
5004456 Botterbusch et al. Apr 1991 A
5010875 Kato Apr 1991 A
5024655 Freeman et al. Jun 1991 A
5042915 Akutsu et al. Aug 1991 A
5053046 Janese Oct 1991 A
5058568 Irion et al. Oct 1991 A
5078702 Pomeranz Jan 1992 A
5084043 Hertzmann et al. Jan 1992 A
5085631 Leighton Feb 1992 A
5090959 Samson et al. Feb 1992 A
RE33854 Adair Mar 1992 E
5101807 Kawashima Apr 1992 A
5125906 Fleck Jun 1992 A
5127393 McFarlin et al. Jul 1992 A
5131382 Meyer Jul 1992 A
5134469 Uchimura Jul 1992 A
5143475 Chikama Sep 1992 A
5151096 Khoury Sep 1992 A
5160559 Scovil et al. Nov 1992 A
5167221 Chikama Dec 1992 A
5168864 Shockey Dec 1992 A
5188594 Zilberstein Feb 1993 A
5195541 Obenchain Mar 1993 A
5197649 Bessler et al. Mar 1993 A
5199417 Muller et al. Apr 1993 A
5199950 Schmitt et al. Apr 1993 A
5215105 Kizelshteyn et al. Jun 1993 A
5217454 Khoury Jun 1993 A
D338958 Jensen Aug 1993 S
5232442 Johnson et al. Aug 1993 A
5242454 Gundlach et al. Sep 1993 A
5251611 Zehel et al. Oct 1993 A
5267573 Evans et al. Dec 1993 A
5271381 Ailinger et al. Dec 1993 A
5273535 Edwards et al. Dec 1993 A
D343678 Snoke et al. Jan 1994 S
5275151 Shockey et al. Jan 1994 A
D347473 Nitzsche May 1994 S
5307803 Matsuura et al. May 1994 A
5325845 Adair Jul 1994 A
5328467 Edwards et al. Jul 1994 A
D349340 Snoke et al. Aug 1994 S
5342299 Snoke et al. Aug 1994 A
D350605 Williams Sep 1994 S
5344397 Heaven et al. Sep 1994 A
D351652 Thompson et al. Oct 1994 S
5354266 Snoke Oct 1994 A
5381782 DeLaRama et al. Jan 1995 A
5396880 Kagan et al. Mar 1995 A
5399164 Snoke et al. Mar 1995 A
5415158 Barthel et al. May 1995 A
D359801 Buyhin et al. Jun 1995 S
5423311 Snoke et al. Jun 1995 A
5437636 Snoke et al. Aug 1995 A
5496269 Snoke Mar 1996 A
5526820 Khoury Jun 1996 A
5531687 Snoke et al. Jul 1996 A
5542924 Snoke et al. Aug 1996 A
D382959 Arpe Aug 1997 S
D384741 Musgrave et al. Oct 1997 S
5857996 Snoke Jan 1999 A
6010493 Snoke Jan 2000 A
Foreign Referenced Citations (16)
Number Date Country
1213571 Mar 1966 DE
3916288 Nov 1989 DE
3916288 Nov 1989 DE
EP0489937 Jul 1990 DE
0 343 094 Jan 1989 EP
0 370 158 May 1990 EP
0389453 Sep 1990 EP
0 489 937 Jun 1992 EP
990417 Sep 1951 FR
2 655 548 Jun 1991 FR
WO8800810 Feb 1988 WO
WO91 01772 Feb 1991 WO
WO9111213 Aug 1991 WO
WO9315648 Aug 1993 WO
WO9427666 Dec 1994 WO
WO 9427666 Dec 1994 WO
Related Publications (1)
Number Date Country
20020198456 A1 Dec 2002 US
Continuations (6)
Number Date Country
Parent 09351388 Jul 1999 US
Child 10216715 US
Parent 09066884 Apr 1998 US
Child 09351388 US
Parent 08957998 Oct 1997 US
Child 09066884 US
Parent 08606084 Feb 1996 US
Child 08957998 US
Parent 08321174 Oct 1994 US
Child 08606084 US
Parent 08129331 Sep 1993 US
Child 08321174 US
Continuation in Parts (3)
Number Date Country
Parent 07908403 Jul 1992 US
Child 08129331 US
Parent 07963431 Oct 1992 US
Child 07908403 US
Parent 07970490 Nov 1992 US
Child 07963431 US