The Relationship of Tension-Free Vaginal Tape Insertion and the Vascular Anatomy Tristi W. Muir, MD, Paul K. Tulikangas, MD, Marie Fidela Paraiso, MD, and Mark D. Walters, MD OBJECTIVE: To describe the proximity of the major vessels in the retropubic space and anterior abdominal wall to the tension-free vaginal tape needle. METHODS: Tension-free vaginal tape needles were inserted bilaterally in ten cadavers. Dissection of the superficial epigastric, inferior epigastric, external iliac, and obturator vessels was performed. Measurements from the lateral aspect of the needle to the medial edge of the vessels were recorded. In an additional cadaver, three planes were created by placing a string from the midlabia to the shoulder, mid– biceps brachii muscle, and 6 cm lateral to the mid– biceps brachii muscle of the cadaver’s extended, ipsilateral arm. An operator, blinded to the retropubic space anatomy, passed the needle in these planes bilaterally. The distances from the needle to the external iliac and obturator vessels were measured. RESULTS: All vessels measured were lateral to the tensionfree vaginal tape needle. The mean distance from the tension-free vaginal tape needle to the obturator vessels was the closest: 3.2 cm (range 1.6 – 4.3 cm). The mean distance from the tension-free vaginal tape needle to the superficial epigastric vessels was 3.9 cm (range 0.9 – 6.7); to the inferior epigastric vessels, 3.9 cm (range 1.9 – 6.6 cm); and to the external iliac vessels, 4.9 cm (range 2.9 – 6.2 cm). When the needle was directed 6 cm lateral to the mid– biceps brachii muscle, the external iliac vein was punctured. CONCLUSION: The major vessels in the retropubic space and anterior abdominal wall lie 0.9 – 6.7 cm lateral to the tension-free vaginal tape needles. If the tension-free vaginal tape needle is laterally aimed or rotated, major vascular injury can occur. (Obstet Gynecol 2003;101:933– 6. © 2003 by The American College of Obstetricians and Gynecologists.)
The tension-free vaginal tape (Gynecare, a division of Ethicon Inc., Sommerville, NJ) procedure has emerged as a popular corrective operation for genuine stress urinary incontinence. Four- to 6-year follow-up data in From the Department of Obstetrics and Gynecology, The Cleveland Clinic Foundation, Cleveland, Ohio; and University of Connecticut Health Center, Farmington, Connecticut.
women with genuine stress urinary incontinence, recurrent genuine stress urinary incontinence, intrinsic sphincter deficiency, and mixed urinary incontinence who underwent a tension-free vaginal tape procedure were recently published.1– 4 The tension-free vaginal tape cure rates were 74 – 85% and demonstrated durability with time. The tension-free vaginal tape procedure introduces unique aspects to the sling procedure. Small anterior vaginal and abdominal wall incisions are used, and there is minimal periurethral and suprapubic dissection. This allows for a more rapid recovery with less postoperative pain than with most other incontinence procedures.5 The polypropylene mesh is placed at the midurethra with less tension than traditional pubovaginal slings, reducing anatomic distortion and postoperative voiding dysfunction.6,7 The technique of mesh placement is unique. A curved, 5-mm needle is placed transvaginally through the periurethral endopelvic fascia, traversing the retropubic space in an upward direction and piercing the anterior abdominal wall close to the pubic symphysis. Most previously described sling procedures employ a downward pass with a smaller-diameter needle and frequently use blunt finger dissection in the retropubic space to guide the needle safely into the vagina. This new technique of needle passage has resulted in major vessel injuries and retropubic hematomas that generally have not been described with sling procedures.8 –12 We believe that these vascular injuries and hematomas usually result when the upward needle passage deviates in a lateral or cephalad direction from a “safe zone” in the retropubic space and anterior abdominal wall. The purpose of this study was to describe the surgical and vascular landmarks of the tension-free vaginal tape needle placement. MATERIALS AND METHODS Ten fresh-frozen cadavers were used for the study. Each cadaver was placed in dorsal lithotomy position with the legs in candy cane leg holders. Bilateral, 1-cm abdominal skin incisions were made 2 cm from the midline and 1 cm
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above the pubic bone. The vaginal epithelium was grasped in the midline of the anterior vaginal wall. A 1.5-cm sagittal incision 1 cm proximal to the external urethral meatus was made. Minimal dissection was performed bilaterally under the vaginal epithelium to develop lateral periurethral spaces to the inferior pubic rami. The tension-free vaginal tape needle was positioned under the vaginal epithelium in the lateral periurethral space. The needle was inserted through the urogenital diaphragm in a plane directed toward the cadaver’s ipsilateral shoulder. After piercing the urogenital diaphragm, the needle was angled to ascend vertically through the retropubic space, with the surgeon trying to maintain contact with the back of the pubic symphysis. The needle was brought up through the abdomen at the 1-cm incision site and clamped in place with a Kelly clamp. The second needle was inserted on the contralateral side in a similar fashion and clamped in place with a Kelly clamp. Vertical abdominal skin incisions were made bilaterally in the vertical plane of the anterior superior iliac spine, from the level of the umbilicus extending caudad onto the anterior thigh. A transverse skin incision was made from the vertical incision to approximately 1 cm lateral to the tension-free vaginal tape needle. Dissection was performed to identify the superficial epigastric vessels, inferior epigastric vessels, external iliac vessels, and the obturator vessels. The point at which the vessel was closest to the tension-free vaginal tape needle, in a plane parallel to the floor, in the retropubic space or anterior abdominal wall, was measured. The distances were measured from the lateral edge of the needle to the medial edge of the vessel. Measurements were made using calipers, which were then placed on a measuring tape to determine the distance; this distance was recorded. The first author made all of the measurements. In a cadaver in which the retropubic dissection was completed, an experienced surgeon (MDW) passed the tension-free vaginal tape needle in three planes while maintaining contact with the back of the pubic bone. The cadaver’s arm was extended perpendicular to the sagittal plane of the body. A barrier was constructed such that the surgeon was blinded to the anatomy of the retropubic space. The three planes were constructed sequentially by placing a string from the cadaver’s mid–labia majora to the following: point 1, the ipsilateral shoulder; point 2, the mid– biceps brachii muscle; and point 3, 6 cm lateral to the mid– biceps brachii muscle (Figure 1). The distances from the lateral aspect of the tension-free vaginal tape needle to the medial aspect of the obturator vessels and external iliac vein were measured as described above. This procedure was performed bilaterally and measurements recorded.
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Figure 1. The tension-free vaginal tape needle is directed in three planes during insertion: the plane from mid–labia majora to the ipsilateral shoulder (a), the plane from mid–labia majora to the mid– biceps brachii muscle (b), and the plane from the mid–labia majora to 6 cm beyond the mid– biceps brachii muscle (c). Muir. TVT and Vascular Anatomy. Obstet Gynecol 2003.
RESULTS All tension-free vaginal tape needles passed through the retropubic space lateral to the bladder. All vessels measured in the ten cadavers were lateral to the tension-free vaginal tape needle. The mean distances from the tension-free vaginal tape needle to the vessels studied were 3.2– 4.9 cm (Table 1 and Figure 2). The ranges of Table 1. Mean Distance and Range From the Lateral Margin of the TVT Needle to the Medial Edge of Vessels in the Anterior Abdominal Wall and Retropubic Space Vessel
Distance from the vessel to the TVT needle
Superficial epigastric Inferior epigastric External iliac Obturator
3.9 (0.9–6.7) 3.9 (1.9–6.6) 4.9 (2.9–6.2) 3.2 (1.6–4.3)
TVT ⫽ tension-free vaginal tape. Numbers are expressed as mean cm (range).
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Figure 2. The relationship of the tension-free vaginal tape (TVT) needle to the vascular anatomy of the anterior abdominal wall and retropubic space. Numbers represent the mean distance from the lateral aspect of the tension-free vaginal tape needle to the medial edge of the vessels. a ⫽ artery; v ⫽ vein. Muir. TVT and Vascular Anatomy. Obstet Gynecol 2003.
measurements from each blood vessel are shown in Table 1, thus reflecting the nearest that the tensionfree vaginal tape needle came to each blood vessel. The tension-free vaginal tape needle was 0.9 cm from the superficial epigastric vessels in one cadaver, and 1.6 cm from the obturator vessels in another cadaver. The distances from the tension-free vaginal tape needle to the external iliac vessels and obturator vessels varied when the operating surgeon directed the tensionfree vaginal tape needle laterally (Table 2). The external iliac and obturator vessels were more than 3.5 cm from the tension-free vaginal tape needle when the surgeon directed the tension-free vaginal tape needle toward the cadaver’s ipsilateral shoulder. When directed 6 cm lateral to the midportion of the biceps brachii muscle, one pass of the tension-free vaginal tape needle penetrated the external iliac vein. DISCUSSION Major vascular injuries have occurred with the tensionfree vaginal tape procedure.8 –12 A United States Food Table 2. Distance From the TVT Needle to External Iliac and Obturator Vessels When the Insertion Is Directed in Three Planes
Mid-biceps brachii muscle
External iliac Obturator
3.6, 3.8 3.9, 4.0
1.6, 1.7 2.5, 2.5
6 cm lateral to mid-biceps brachii muscle 0, 0.6 0.9, 1.2
TVT ⫽ tension-free vaginal tape. Numbers represent the needle passage on each side in one cadaver (cm).
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and Drug Administration Web site, which includes selfreported surgical complications, describes injuries to the inferior epigastric, obturator, external iliac, and femoral vessels.8 Two deaths secondary to vascular injury are included in the data. Case reports recently have been published, describing retropubic hematomas requiring transfusion and catastrophic bleeding requiring surgical intervention as a result of the tension-free vaginal tape procedure.9 –11 The Austrian registry describes a reoperation rate of 0.7% for hematomas after tension-free vaginal tape placement in 2798 patients.12 Our study demonstrates that the major vascular structures of the pelvis are lateral to the ideal placement of the tension-free vaginal tape needle. Lateral deviation of the tension-free vaginal tape needle may occur with a variety of situations. Bladder perforation occurs in approximately 2.7% of patients undergoing the tension-free vaginal tape procedure.12 A surgeon may purposefully direct the tension-free vaginal tape needle laterally to avoid bladder perforation. The tension-free vaginal tape needle also may assume a lateral course if the patient moves while under local anesthesia.10 The external iliac vessels and the obturator vessels are also cephalad to the ideal placement of the needle. The lateral pubic ramus curves in a cephalic direction. Therefore, if the placement of the tension-free vaginal tape needle is directed laterally, the back of the pubic bone will direct the needle cephalad as the surgeon traverses the retropubic space directly behind the pubic bone. Deviation in a cephalad direction also may occur if the surgeon loses control of the needle following perforation of the urogenital diaphragm. Vascular and bowel injury can occur.
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Attention to maintaining a position behind the pubic bone is important throughout the procedure. The tension-free vaginal tape needle may be misdirected at the site of insertion. If a position behind the pubic bone is not initiated when the needle is directed toward the anterior abdominal wall, the needle may traverse the labia majora in front of the pubic bone, and injury to the femoral vessels can occur. An understanding of the unique aspects of an upward pass versus a downward pass through the retropubic space is essential. During a traditional sling procedure, the surgeon’s finger may be placed in the retropubic space to guide the needle, or touch sensation may be gained by tapping the back of the pubic bone with the downward pass needle. A small deviation at the point of insertion will lead to a magnified deviation at the exit point of the needle. With a blind upward pass behind the pubic bone, awareness of the tip of the tension-free vaginal tape needle may be lost. A small lateral or cephalad deviation at the point of insertion may not be detected until the needle is palpated through the anterior abdominal wall, and this may result in a vascular injury. To avoid vascular injury, the surgeon should direct the tension-free vaginal tape needle in a plane from the mid–labia majora toward the ipsilateral shoulder while maintaining a position directly behind the pubic bone. With the patient draped and an anesthesia screen in place, it may be difficult for the surgeon to visualize the ipsilateral shoulder for needle passage. Subsequent to preparation of the patient, but prior to draping, a marking pen may be used to mark the plane from the insertion point to the ipsilateral shoulder. The surgeon should stay in this plane and avoid lateral or cephalad deviation. Newly published manufacturer’s recommendations by Gynecare (2001 Gynecare TVT Professional Education Program Speaker’s Guide) state that Allen-type stirrups should be used for positioning to help avoid vascular injury. To date, however, the type of leg stirrups and the degree of flexion at the hips in positioning the patient and their effect on the vascular anatomy associated with the tension-free vaginal tape procedure have not been published. The tension-free vaginal tape procedure is an exciting, new, effective outpatient procedure that may be performed under local anesthesia. As the procedure grows in popularity, fewer retropubic colposuspension procedures may be done. With a decline in open or laparoscopic retropubic operations, surgeons may be less familiar with the anatomy of the retropubic space. The unique upward pass approach to sling placement with tensionfree vaginal tape has been associated with injury to the external iliac, obturator, and femoral vessels; these injuries have not been described with a downward pass procedure. The surgeon performing the tension-free vaginal tape
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procedure must have an understanding of the anatomy of the retropubic space and anterior abdominal wall to try to avoid rare, but life-threatening, complications. REFERENCES 1. Nilsson CG, Kuuva N, Falconer C, Rezapour M, Ulmsten U. Long-term results of the tension-free vaginal tape (TVT) procedure for surgical treatment of female stress urinary incontinence. Int Urogynecol J 2001;12 Suppl 2:S5–8. 2. Rezapour M, Ulmsten U. Tension-free vaginal tape (TVT) in women with recurrent stress urinary incontinence—a longterm follow up. Int Urogynecol J 2001;12 Suppl 2:S9–11. 3. Rezapour M, Falconer C, Ulmsten U. Tension-free vaginal tape (TVT) in stress incontinent women with intrinsic sphincter deficency (ISD)—a long-term follow-up. Int Urogynecol J 2001;12 Suppl 2:S12–4. 4. Rezapour M, Ulmsten U. Tension-free vaginal tape (TVT) in women with mixed urinary incontinence—a longterm follow-up. Int Urogynecol J 2001;12 Suppl 2:S15–8. 5. Ulmsten U, Henriksen L, Johnson R, Varhos G. An ambulatory surgical procedure for treatment of female urinary incontinence. Int Urogynecol J 1996;7:81–6. 6. Klutke JJ, Carlin BI, Klutke CG. The tension-free vaginal tape procedure: Correction of stress incontinence with minimal alteration in proximal urethral mobility. Urology 2000;55:512–4. 7. Atherton MJ, Stanton SL. A comparison of bladder neck movement and elevation after tension-free vaginal tape and colposuspension. Br J Obstet Gynaecol 2000;107:1366–70. 8. Centers for Devices and Radiological Health. U.S. Food and Drug Administration Manufacturer and User Facility Device Experience Database. Available at: http://www. fda.gov/cdrh/maude.html. Accessed 2002 Apr 17. 9. Vierhout ME. Severe hemorrhage complicating tensionfree vaginal tape (TVT): A case report. Int Urogynecol J 2001;12:139–40. 10. Zilbert AW, Farrell SA. External iliac artery laceration during tension-free vaginal tape procedure. Int Urogynecol J 2001;12:141–3. 11. Walters MD, Tulikangas PK, LaSala C, Muir TM. Vascular injury during tension-free vaginal tape procedure for stress urinary incontinence: A case report. Obstet Gynecol 2001;98:957–9. 12. Tamussino KF, Hanzal E, Kolle D, Ralph G, Riss PA. Tension-free vaginal tape operation: Results of the Austrian registry. Obstet Gynecol 2001;98:732–6. Address reprint requests to: Mark D. Walters, MD, The Cleveland Clinic Foundation, Department of Obstetrics and Gynecology, 9500 Euclid Avenue, A81, Cleveland, OH 44195; E-mail: email@example.com. Received May 14, 2002. Received in revised form September 23, 2002. Accepted November 4, 2002.
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