DEMOGRAPHICS:Pelvic congestion syndrome (PCS) is a rare and, at times, complex condition which may result from one or more anatomical effects: gonadal vein valvular incompetence, non-thrombotic iliac vein lesions, or left renal vein compression. PCS affects approximately 15% of patients aged 18 to 50 years of age although symptomatic presentations may confound these numbers. May-Thurner syndrome (MTS) is the most common form of non-thrombotic iliac vein lesions in which the left common iliac vein is compressed by the right common iliac artery and the spine. Each of these conditions can be associated with chronic pelvic pain.
HISTORY:We present a case of left-sided MTS inducing right-sided PCS. A 31-year-old female with history of multiparity (G4P4), retroverted uterus, and lower extremity varicose vein disease presented to the clinic with symptoms of right-sided pelvic congestion including swelling and dull pain of the right pelvic region with enlarged pelvic and gluteal veins following her most recent pregnancy. She reported episodic right leg more than left leg swelling. She had previously undergone injection sclerotherapy at an outside facility secondary to her engorged pelvic and gluteal veins without significant improvements in her symptoms.
PLAN:The patient was taken for diagnostic venography, bilateral gonadal vein venogram, and intravascular ultrasound (IVUS). She was found to have mostly normal venous vasculature. Her right gonadal vein was noted to be severely engorged with valvular incompetence and an approximately 90% narrowing of the left iliac vein secondary to right iliac artery compression with left-to-right ilioiliac shunting. She subsequently underwent placement of two self-expanding, bare-metal stents across the high-grade left iliac vein stenosis. Post-completion venography demonstrated significant improvement in the left-to-right ilioiliac shunting and resolution of the stenosis. On follow-up examination, she had resolution of her symptoms, and thus no further intervention was warranted despite the known right gonadal vein reflux disease. (Figure 1)
DISCUSSION:
PCS and MTS are rare conditions but both are treatable with appropriate diagnosis and imaging. Our case demonstrates the complex anatomy that can occur in patients presenting with pelvic congestion-like symptoms. Proper identification of the ultimate etiology can direct correct therapies in these patients. 
