Aorto-mesenteric compression of the left renal vein as a cause of varicocele in adolescents: a clinical observation of spontaneous recovery

Nutcracker Syndrome—How Well Do We Know It?

Nutcracker phenomenon or renal vein entrapment is classically seen as a compression of renal vein in between abdominal aorta and superior mesenteric artery with patients being asymptomatic or clinically manifested in the form of nutcracker syndrome as proteinuria, hematuria, flank pain, pelvic congestion in women, and varicocele in men. In this report, we are presenting a case of rare variant of nutcracker phenomenon along with brief review of anatomy, pathophysiology, public health, and clinical significance of nutcracker syndrome. On a routine dissection of an adult male cadaver, we noticed an unusual arrangement of the structures at the hilum of the left kidney showing entrapment of renal vein between left anterior inferior and posterior segmental renal arteries. The variation in the course of left anterior inferior segmental renal artery leads to compression of left renal vein at renal hilum. Therefore, we have named this rare abnormal anatomical entity as hilar nutcracker phenomenon. The structures in the right renal hilum are normal. The objective of this paper is to report an unusual but important variant of nutcracker phenomenon and also give collective knowledge of such anatomical variations in renal vasculature that will help in diagnosing and treating such rare renal disorder.

The Nutcracker phenomenon is a rare asymptomatic compression of the left renal vein. Among various types of this condition, the entrapment of the left renal vein between the superior mesenteric artery and abdominal aorta is common. This phenomenon could affect underweight individuals because of the paucity of adipose tissue in the retroperitoneum, which decreases the angle between the superior mesenteric artery and the aorta. Symptomatic compression of the left renal vein is known as Nutcracker syndrome. Duplex sonography of renal veins and contrast-enhanced abdominal computed tomography are commonly used to diagnose the Nutcracker phenomenon and syndrome.

Mesoaortic Compression of the Left Renal Vein (Nutcracker Syndrome): Case Reports and Review of the Literature

The use of multidetector computed tomography (MDCT) in routine abdominal explorations has increased the detection of the nutcracker phenomenon, defined as left renal vein (LRV) compression by adjacent anatomic structures. The embryology and anatomy of the nutcracker phenomenon are relevant as a background for the nutcracker syndrome, a rare cause of hematuria as well as other symptoms. MDCT examples of collateral renal vein circulation (gonadal, ureteric, azygous, lumbar, capsular) and aortomesenteric (anterior) and retroaortic (posterior) nutcracker phenomena in patients with no urologic complaint are shown as well as studies performed on patients with gross hematuria of uncertain origin. Incidental observation of collateral veins draining the LRV in abdominal MDCT explorations of asymptomatic patients may be a sign of a compensating nutcracker phenomenon. Imbalance between LRV compression and development of collateral circulation may lead to symptomatic nutcracker syndrome.

A case of nutcracker syndrome: Treatment by mesoaortic transposition

Gross hematuria of uncommon origin: The nutcracker syndrome

Re: Endovascular Stent Placement for the Treatment of Nutcracker Phenomenon in Three Pediatric Patients

Weight loss as a potential trigger for nutcracker syndrome after a complex surgery: About a case report

BackgroundPosterior nutcracker syndrome is defined by the compression of the left renal vein between the abdominal aorta and a lumbar vertebral body. It can be clinically manifest with intermittent hematuria, gonadal or spermatic reflux resulting in varicocele. Ultrasound is the first-line imaging which require more accurate study with contrast-enhanced computed tomography. Management can be conservative in younger patients with mild hematuria due to the high spontaneous remission rate and invasive with open surgical and endovascular interventions. We describe a very rare case with compression of the left renal vein due to an osteophyte of the spine.Case presentationA 62-year-old Caucasic male came to our radiology department for chronic hepatitis B virus (HBV)-related liver disease follow-up and mild scrotal pain. The ultrasound examination revealed a compression of the left retro-aortic renal vein in the aorto-vertebral space caused by an osteophyte. Duplex Doppler ultrasound revealed flow congestion in the left renal vein and renal failure; power Doppler ultrasound showed left varicocele.ConclusionsDoppler ultrasound is the first-line imaging and allows the detection of all the typical signs of posterior nutcracker: left renal vein stenosis, flow congestion and renal failure. Nutcracker syndrome should be suspected in older patients with left varicocele associated with hematuria. Failure to diagnose and treat these patients could have serious consequences for their health.

The nutcracker syndrome is defined by the compression of the left renal vein between the aorta and superior mesenteric arteries, accompanied by a classic, but less specific, symptomatology. We reported a case of a 37-year-old woman who had been investigated because of intermittent gross hematuria of unknown origin. Computed tomographic angiography revealed compression of the left renal vein as it ran between the superior mesenteric artery and the abdominal aorta, associated with significant dilation of the left ovarian vein. The nutcracker syndrome, caused by compression of the left renal vein by the aorta and superior mesenteric arteries, is probably more prevalent in women, and it is caused by specific situations, such as renal ptosis and paucity of retroperitoneal fat. Hematuria, a typical symptom, is due to rupture of the thin-walled septum separating the veins of the urinary collecting system. Imaging tests may help with the diagnosis. The best treatment is still elusive, but there are several surgical approaches, such as intravascular stenting, and also a conservative management. Diagnosis is usually delayed, and the syndrome should be included in the differential of hematuria of unknown origin.

Nutcracker syndrome due to left-sided inferior vena cava compression and treated with superior mesenteric artery transposition

Double trouble: A case report of concurrent superior mesenteric artery syndrome and nutcracker syndrome in a previously healthy young adult.

We evaluated 3-D computed tomography angiography (3-D CTA) in the diagnosis of the nutcracker phenomenon, and its significance in postoperative follow up. Three-dimensional CTA was used to compare the anatomical relations of the left renal vein with the aorta and the superior mesenteric artery in patients with the nutcracker phenomenon and in a control group. Four patients with the nutcracker phenomenon received a surgical procedure of the transposition of the left renal vein. The 3-D CTA was used for all patients during postoperation follow-up testing. The 3-D CTA showed a compression of the left renal vein between the aorta and the superior mesenteric artery (SMA) and the abnormal acute angle between them. The angles and distances between the SMA and the aorta were 39.3 +/- 4.3 degrees and 3.1 +/- 0.2 mm in the patient groups and 90 +/- 10 degrees and 12 +/- 1.8 mm in the control groups, respectively. Differences in angles and distances were statistically significant between the two groups (P < 0.05). Surgical transposition of the left renal vein was performed successfully. Postoperative 3-D CTA revealed the distance between the SMA and the aorta was nearly normal. The reconstruction imaging of the renal vein by means of 3-D CTA revealed that unusual hematuria was due to compression of the left renal vein; therefore it may be a useful alternative imaging technique instead of conventional examinations. The non-invasive 3-D CTA may be a useful tool in the diagnosis of the nutcracker phenomenon and follow-up testing.

Mesoaortic compression of the left renal vein (the so-called nutcracker syndrome): repair by a new stenting procedure.