Systematic Review
Forty articles met our selection criteria, as described in Figure 1. Of these, four were case series. [9, 37, 38, 43] The remaining 36 articles were individual case reports. [4-8, 10-36, 39-42]. From these forty articles, 66 individual cases were reported. Our seven clinical cases were included for a total of 73 cases. (Table 1)
The majority of the patients were young females complaining of left flank pain and/or hematuria. Age at diagnosis ranged from 18 to 77. Mean age was 36 and median was 34. Eight-two percent of patients were below age 50. The majority of patients (79.5%) were female. The most common presenting symptom was left flank pain (61.6%), followed by hematuria (52.1%), which included both gross and microscopic hematuria. About a third of patients (37.0%) complained of pelvic pain. Notably, 24.7 percent experienced urogenital symptoms such as pelvic congestion syndrome, dyspareunia, dysmenorrhea, urinary frequency, dysuria, or testicular and scrotal pain. A handful of patients (12.3%) had concomitant superior mesenteric artery syndrome (SMAS) and 11.0 percent had concomitant May-Thurner syndrome (MTS).
LRV location was mostly anterior. Only three patients had posterior NCS–one of our clinical cases and two case reports. [14, 17]. Location was not described in 37 percent of cases. Forty-one patients had anterior compression, which is 56.2 percent of the total and 89.1 percent of cases that reported location. One case described a patient with an anterior and posterior LRV, both of which were compressed. [13] Another report described compression of the LRV by a dilated splenic vein, in a patient with splenomegaly. [29] Imaging revealed enlarged gonadal veins, adnexal varices, or varicocele in 42.5 percent of cases.
Some form of computed tomography (CT) was used in the vast majority of cases (93.2%). This includes CT abdomen pelvis, CT angiogram (CTA), and CT venogram (CTV). Of the five cases that did not use CT, four used MRI. One case used Doppler ultrasound alone to diagnose NCS. In 21 cases (28.8%), ultrasound was used in combination with one of the forms of CT. Angiography, venography, and intravascular ultrasound (IVUS) were also used but generally as part of an intervention rather than primary diagnosis. Exploratory laparotomy or diagnostic laparoscopy was also seen in three cases when a diagnosis other than NCS was suspected.
Treatment modality was variable, although endovascular stenting was most common, appearing in 38.4% of cases. Other endovascular therapies included embolization of a left ovarian vein and a left second lumbar vein respectively in two cases. Two of the LRV stent cases also included embolization of the left ovarian vein. Medical management, including anti-hypertensives, pain medication, and nutritional support were found in only 12.3 percent of cases. There were a wide variety of non-endovascular procedures done. The most common was LRV transposition, done in 15.1 percent. Four of these were noted to have been done with a retroperitoneal approach. There were six cases (8.2%) in which robot-assisted laparoscopic extravascular LRV stenting was performed. Other surgical options included robot-assisted laparoscopic LRV PTFE cuff placement (3 cases), LRV bypass with femoral vein graft (1 case) or PTFE (1 case), gonadal vein transposition (2 cases), varicocele ligation, gonadal vein ligation, renal autotransplant, splenectomy, and nephrectomy. Five cases did not provide information on treatment, symptoms resolved spontaneously, or treatment of another condition (i.e. SMAS) resulted in relief of symptoms.