Types: Oral presentation

Abstract No: 0203

Authors: J Holdstock1, A White1, T Fernandez-Hart1, D Beckett1, J Nemchand1, M Whiteley1

Institution: 1The Whiteley Clinic, Guildford, United Kingdom

Purpose: In June 2016 we introduced trans-abdominal duplex ultrasound (TADUS) alongside our existing routine trans-vaginal duplex ultrasound (TVDUS) performed for pelvic venous reflux(1). We performed these scans for diagnosis at initial presentation and repeated this at 6-8weeks following Pelvic Vein Embolization (PVE). Our aim was to: 1) Identify the proximal extent of Left Ovarian Vein (LOV) reflux. 2) Evaluate the left renal vein (LRV) and identify or exclude Nutcracker phenomenon as a cause of LOV reflux(2). 3) Compare any change in appearance or caliber of the LRV following PVE.

Materials Methods: 24 female patients (age 26-68, mean 44) underwent PVE between September 2016 and April 2017. TADUS was performed with patients erect and 30 degrees recumbent to examine the LRV (3)(2). Diameters of the hilar and mesoaortic LRV and ratios were recorded at diagnosis and after PVE. A hilar to mesoaortic diameter ratio of greater than 5 raised suspicion of Nutcracker Phenomenon (4). Group 1, 11 patients. All exhibited proximal and distal LOV reflux prior to PVE. 2 presented with debilitating Pelvic Congestion Syndrome (PCS) but no leg Varicose Veins (VV), 7 with leg VV and moderate pelvic symptoms, 2 with leg VV with pelvic communication but no pelvic symptoms. Group 2, 10 patients. 8 with no LOV reflux, 2 exhibiting reflux only in the distal segment of the LOV. All presented with leg VV communicating with the pelvis. Only 2 patients exhibited pelvic symptoms. 3 patients excluded. 1 with May Thurner. 1 with aberrant anatomy. 1 failed embolization of the LOV due to tortuosity.

Results: Group 1: 11 patients with LOV reflux had pre PVE hilar to mesoaortic diameter ratios with a mean of 5.0 and post PVE diameter ratios with a mean 2.0 (p=0.001) Group 2: 10 patients, 8 without LOV reflux and 2 with LOV reflux distally had pre PVE ratios with a mean of 2.1 and post PVE with a mean ratio of 2.0 (p=0.799) 5 patients in Group 1 had hilar to mesoaortic diameter ratios >5 prior to PVE with suspicion of Nutcracker (see table). These 5 included both patients with PCS who experienced complete symptomatic resolution post PVE. Post PVE all patients in Group 1 had diameter ratios

Conclusion: Nutcracker phenomenon has previously been suggested as a cause of LOV reflux, secondary to obstructive flow and increased venous pressure due to compression of the left renal vein between the Aorta and superior mesenteric artery. However, in this study, LOV reflux appeared to cause a siphon effect, with LRV drainage preferentially following the LOV reflux path. This results in physiological narrowing of the mesoaortic LRV. This effect is relieved following successful embolization of the LOV. References: 1 Trans vaginal duplex ultrasonography appears to be the gold standard investigation for the haemodynamic evaluation of pelvic venous reflux in the ovarian and internal iliac veins in women. Whiteley MS, Dos Santos SJ, Harrison CC, Holdstock JM, Lopez AJ 2 A standardized ultrasound approach to pelvic congestion syndrome. Nicos Labropoulos, Patrick T Jasinski, Demetri Adrahtas, Antonios P Gasparis, Mark Meissner. 3 Nutcracker syndrome in children: the role of the upright position examination and superior mesenteric artery angle measurement in the diagnosis. Fitoz S, Ekim M, Ozcakar ZB, Elhan AH, Yalcinkaya F 4 Nutcracker syndrome: diagnosis with Doppler US, SH Kim, SW Cho, HD Kim, JW Chung, JH Park, MC Han