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Oral Presentations

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FRIDAY, NOVEMBER 11, 2005 (12:00 NOON–12:10 PM)

FRIDAY, NOVEMBER 11, 2005 (12:10 PM–12:20 PM)

Plenary 12—Basic Research

Plenary 12—Basic Research

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Comparison of Lateral Thermal Spread in Four Electrosurgical Devices Using Real-Time Thermography Advincula AP, Ko AC, Ganju R, Burke WM, Reynolds RK. University of Michigan, Ann Arbor, Michigan; University of Michigan, Ann Arbor, Michigan; Elastic Design, LLC, San Bruno, California; University of Michigan, Ann Arbor, Michigan; University of Michigan, Ann Arbor, Michigan

Adaptative Media Remodeling of the Uterine Artery During Pregnancy Abilez O, Alsac J, Nezhat CH, Heikkinen M, Zarin C, Nezhat C. Stanford University Medical Center, Palo Alto, California; Stanford University Medical Center, Palo Alto, California; Palo Alto, California; Palo Alto, California; Stanford University Medical Center, Palo Alto, California; The Center for Minimally Invasive Surgery, Palo Alto, California

Study Objective: To compare the actual lateral thermal spread of four commonly used electrosurgical devices. Design: A protocol was approved by the University Committee on Use and Care of Animals. Funding was secured through an unrestricted educational grant from industry. A porcine model involving 4 anesthetized and opened pigs was utilized to gather data under live blood-flow conditions. Each pig was assigned to one of four 5 mm electrosurgical devices: Gyrus Plasmakinetic Bipolar Cutting Forceps, Enseal Vessel Sealer, Ligasure Atlas V Vessel Sealer (LS1500), and SonoSurg Ultrasonic Scissors. In-situ dynamic thermography was undertaken with a thermal imaging camera. Thermal imaging measurements were taken during typical power cycles of the individual devices. Real-time temperatures were measured by utilizing a 54° centigrade contour lateral to the margin of the jaws of the device. Peak temperatures were obtained from the tissue within the jaws of each device. Setting: Animal surgery operating room at the University of Michigan School of Medicine. Intervention: Application of the electrosurgical devices to five targeted vessels: right renal artery, right and left lumbar vein, right and left iliac artery. Measurements and Main Results: The preliminary mean lateral thermal spread and peak temperatures for the 4 devices respectively are as follows: Enseal-1.10 mm (95%CI 0.92–1.28) and 86.9°C, Gyrus–2.78 mm (95%CI 1.88 –3.68) and 104.7°C, Ligasure 3.23 mm (95%CI 0.95–5.51) and 96.9°C, and SonoSurg 2.98 mm (95%CI 2.08 –3.88) and 180°C. Statistical differences between the four devices were calculated using the Paired Student’s t-test. Given the minimal lateral thermal spread, only the Enseal comparisons are reported. Enseal versus Gyrus: 1.68 mm (95%CI 0.95–2.41), Enseal versus Ligasure: 2.13 mm (95%CI 0.004 – 4.26), Enseal versus SonoSurg: 1.88 mm (95%CI 1.13–2.63). Conclusion: The Enseal device produces lower peak temperatures and demonstrably less thermal spread to surrounding tissues.

Study Objective: The purpose of this study was to compare the morphological changes in the arterial wall of the abdominal aorta (AA), the femoral artery (FA), and the uterine artery (UA), in response to blood flow (BF) variations induced by pregnancy on a rabbit model. Design: Prospective experimental study. Setting: Basic Science Laboratory. Patients: Three groups of rabbits: 7 control rabbits before pregnancy, 8 rabbits at 3 weeks of pregnancy, and 7 rabbits at 3 weeks postpartum. Intervention: Blood flow, morphometry, and histology was performed on the abdominal aorta (AA), femoral artery (FA), and uterine artery (UA) in 3 groups of rabbits: 7 control rabbits before pregnancy, 8 rabbits at 3 weeks of pregnancy, and 7 rabbits at 3 weeks postpartum. BF in these 3 arteries was measured at the same standard location for each of them, using the electromagnetic flow meter (Nihon Kohden). After death by an injection, the vessels were perfusion-fixed immediately with 4% paraformaldehyde through the suprarenal AA. Specimens of each vessel were taken at the same level and further fixed in 4% paraformaldehyde for 24 hours for paraffin sections. Morphometry and histology were performed on paraffin sections with staining of hematoxylin and eosin and Weigern-Van Gieson’s procedure for elastin staining. Arterial dimensions, including lumen radius (LR), medial cross sectional area (MCSA), media thickness (MT), and SMC medial density were measured with computer-assisted digitizer. Wall shear stress, in newtons per square meter (Pa), was calculated assuming Poiseuilee flow: WSS (Pa) ⫽0.03X4 (BF)/60 pi (LR) 3. Measurements and Main Results: BF was significantly elevated in each vessel about 2.5-fold during pregnancy compared to control, and decreased significantly 3 weeks after delivery. During pregnancy, the lumen radius increased significantly in each vessel compared to control, in order increase the wall shear stress in the AA, to keep it to the same level as control in the FA and to decrease it in the UA. This adaptation of the arterial wall did not require any significant morphometric changes in the AA and the FA, but the UA presented a significant media thickening, elastin laminae degradation, and SMC hypertrophy during pregnancy. The morphometric changes in the UA media were reversible after delivery.

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Journal of Minimally Invasive Gynecology, Vol 12, No 5, September/October Supplement 2005

Conclusion: While the AA and the FA seem to have a passive media remodeling to BF variations induced by pregnancy, the UA shows an adaptative media remodeling.

FRIDAY, NOVEMBER 11, 2005 (11:40 AM–11:50 AM) Plenary 13—Endometriosis 111

FRIDAY, NOVEMBER 11, 2005 (11:30 AM–11:40 AM) Plenary 13—Endometriosis 110 Histological Analysis of Endometrioma: What the Surgeon Needs to Know Muzii L, Bianchi A, Bellati F, Cristi E, Pernice M, Zullo MA, Angioli R, Benedetti Panici PL. Rome, Italy; University Campus Bio-Medico, Rome, Italy; University “La Sapienza” of Rome, Rome, Italy; Rome, Italy; University Campus Bio Medico, Rome, Italy; University Campus Bio Medico, Rome, Italy; University Campus Bio Medico, Rome, Italy; University “La Sapienza” of Rome, Rome, Italy Study Objective: To evaluate by thorough pathological analysis the histological features of the endometrioma wall. Design: Prospective series of consecutive patients (Canadian Task Force Classification II-2). Setting: Tertiary care, university hospital. Patients: Fifty-nine consecutive patients with ovarian endometriomas. In 11 patients the endometrioma was bilateral, for a total number of 70 excised cysts. Intervention: Patients underwent operative laparoscopy with the stripping technique for excision of the ovarian endometrioma. A thorough histology examination was performed on the entire cyst wall specimen. Measurements and Main Results: Histological examination confirmed the endometriotic nature of the cyst in 100% of the cases. The inner wall of the endometrioma was covered by endometriotic tissue in 60% of the entire surface (ranging from 10% to 98%). The mean cyst wall thickness was 1.4 mm, ranging from 0.8 mm to a maximum of 3.4 mm. The maximal depth of endometriosis penetration in the endometrioma wall was 0.6 mm, ranging from 0.1 to 2.0 mm. In 99% of the cases the maximal penetration of the endometriotic tissue was less than 1.5 mm. Conclusion: Studies form the literature inconsistently report the histological confirmation of the endometriotic nature of the endometrioma to be somewhere between 0% and 100%. In the present study, we demonstrate that the endometrioma wall contains endometriotic tissue in 100% of the cases. However, the endometriotic tissue may cover the inner cyst wall for a surface that varies between 10% and 98% of the entire wall. This tissue may reach a depth of 2 mm, but for most of the surface it rarely penetrates more than 1.5 mm. These histological data may help the gynecological laparoscopist to select the surgical approach that maximally preserves the healthy ovarian tissue.

Deeply Infiltrating Endometriosis: Pathogenetic Implications of the Anatomical Distribution Chapron C, Bricou A, Chopin N, Borghese B, Dousset B, Vacher-Lavenu M. Paris, France; Bauderlocque Hospital, Paris, France; Bauderlocque Hospital, Paris, France; Bauderlocque Hospital, Paris, France; CHU Cochin, Paris, France; CHU Cochin, Paris, France Study Objective: Investigate if the knowledge of the anatomic distribution of histologically proved deeply infiltrating endometriosis (DIE) lesions contributes to understand pathogenesis. Design: Observational study between June 1992 and December 2004 (retrospective study between 1992 and 2000; prospective study between 2001 and 2004). Patients: Continuous series of 426 patients suffering from pelvic pain who underwent complete surgical exeresis for DIE. Intervention: DIE lesions were classified according to four different possibilities: (1) DIE lesions were classified as located in the anterior or posterior pelvic compartment. By definition anterior DIE was defined as bladder DIE and posterior DIE included the other pelvic DIE locations: uterosacral ligament (USL), vagina, ureter and intestine. (2) DIE were classified as left, median and right. By definition we classified as left DIE lesions the following (left USL, left ureter, sigmoid colon, descending colon), as median DIE lesions the following (bladder, vagina, rectum, rectosigmoid junction, transverse colon, small intestine, omentum) as right DIE lesions the following (right USL, right ureter, ascending colon, appendix, ileocecum junction). (3) DIE lesions were classified as pelvic or abdominal. We classified as abdominal DIE lesions the following: descending colon, transverse colon, ascending colon, appendix, ileocecum junction, small intestine, and omentum. All the other DIE locations (bladder, USL, vagina, ureter, rectum, rectosigmoid junction, sigmoid colon) were considered as pelvic DIE lesions; (4) DIE lesions that could presented right and/or left distribution (ureter, USL, . . .) were classified as unilateral or bilateral. Measurements and Main Results: These 426 patients presented 759 histologically proved DIE lesions: bladder (48 lesions; 6.3%); USL (400 lesions, 52.7%); vagina (123 lesions, 16.2%); ureter (16 lesions, 2.1%); intestine (172, 22.7%). Pelvic DIE lesions are significantly more often located in the posterior compartment of the pelvis (682 DIE lesions (93.4%) versus 48 DIE lesions (6.6%); p ⬍ 0.0001). Pelvic DIE lesions are significantly more frequently located on the left side. Patients with unilateral pelvic DIE lesions the anatomic distribution is significantly different in the three groups: left (172 lesions; 32.0%), median (284 lesions; 52.8%) and right (82 lesions; 15.2%) (p ⬍ 0.0001). Patients with lateral lesions, left DIE lesions (172 lesions; 67.8%)