We reviewed the abdomen CT of patients diagnosed with NCS in our hospital during the last year, with different clinical manifestations, that illustrate the spectrum of this syndrome.
DIAGNOSIS
The first step in the diagnosis is a good examination and medical history.
Doppler Ultrasound is the initial diagnostic imaging technique with a sensitivity of 78% and a specificity of 100%. It allows assessing the decrease in the anteroposterior diameter of the LRV and measuring the maximum flow rate before and after passing through the fork formed by the aorta and the SMA considering diagnosis a distal/proximal ratio >5.
The MDTC is very useful to demonstrate the anatomical arrangement of the vessels, the compression of the LRV between the aorta and the SMA, its secondary dilatation and the collateral venous circulation.
Magnetic resonance angiography allows an excellent anatomical assessment and it is a radiation-free alternative to CT.
Retrograde phlebography confirms the diagnosis by demonstrating a reno-cava pressure gradient >3mmHg (the normal value ranges between o and 1 mmHg). It allows visualization of the compression point of the LRV, collaterals, reflux into the gonadal veins, and stagnation of the contrast in the LRV.
TREATMENT
In asymptomatic patients, with limited clinical conditions or in pubertal patients in whom the condition may remit after development, the treatment is conservative. It consists of rest, hydration, an increase in body mass that increases abdominal fat, and secondarily the aortomesenteric angle and ultrasound monitoring.
In symptomatic patients, it can be surgical with techniques that release the renal vein, transposition of the LRV or SMA, gonad-cava or LRV bypass, and nephrectomy.
Interventional endovascular therapy with stent placement and embolization of varicose veins is increasingly booming and displaces the open surgical procedure.