Aneurysm of the left ascending lumbar communicating vein: Its prevalence and possible association with nutcracker phenomenon.

PURPOSE: To evaluate abdominal computed tomography (CT) studies in respect of the prevalence of the left ascending lumbar communicating vein (ALCV) and ALCV aneurysm and to identify possible causes of aneurysm development in the ALCV. METHODS: Contrast-enhanced abdominal CT examinations were retrospectively investigated for the prevalence of the ALCV in the adult population. In patients with ALCV, the diameters of the following vessels were measured: ALCV, left renal vein (LRV) at two levels, compression ratio of the LRV (CR), left gonadal vein, right and left ascending lumbar veins (ALVs). The aortomesenteric angle was also measured for preaortic LRVs. ALCV aneurysm was noted during the assessment. RESULTS: Evaluation was made of 500 patients. ALCV was found in 240 patients (48%), more common in patients with retroaortic LRV and circumaortic LRV than in patients with preaortic LRV (p = 0.003). The mean diameter of the ALCV was 3.85 ± 2.06 mm. ALCV and the left gonadal vein merged to form a common vein draining into the LRV in 23 patients with preaortic LRV (9.6%). Of the patients with ALCV, 19 (8%) had aneurysm. The diameter of the left ALV and CR were significantly greater in patients with aneurysm than in patients without (p = 0.001 and 0.032, respectively). Patients with ALCV aneurysm had a significantly narrower aortomesenteric angle (p = 0.004). CONCLUSION: The results of this study indicated that a narrower aortomesenteric angle and a greater CR might play a role in the development of ALCV aneurysm.

Nutcracker syndrome.

This study represents a concise review of Nutcracker syndrome with its history, incidence, clinical presentation and currently available diagnostic criteria and treatment options. This should help any clinician identify and better serve patients with rare venous disorders such as this. Although the literature is scarce, clinicians should be keen to diagnose and treat patients with this potentially debilitating syndrome.

Caracterización del síndrome de cascanueces / Characterization of Nutcracker Syndrome

Introducción: El síndrome de cascanueces es una anomalía vascular poco buscada y diagnosticada, por su baja incidencia y por la dificultad de sospecharla ante manifestaciones clínicas frecuentes. Objetivo: Examinar las características clínicas e imagenológicas de los pacientes diagnosticados con el síndrome de cascanueces. Método: Estudio descriptivo retrospectivo y prospectivo en pacientes atendidos en el Hospital Pediátrico Universitario William Soler entre enero de 2013 - diciembre de 2017. Cuando se sospechó el síndrome se realizó ultrasonido buscando la dilatación de la vena renal izquierda y el ángulo de salida de la arteria mesentérica superior. En 7 de los pacientes se realizó angio-TAC. Se revisaron variables epidemiológicas, clínicas, de laboratorio e imagenológicas. Presentación de los casos: Del total de 9 pacientes en que se diagnosticó la anomalía vascular, 6 (66,7 por ciento) pertenecen al sexo masculino. La edad media al diagnóstico fue 11,4 años (rango: 7-15). Se diagnosticó cascanueces anterior en 7 (77,7 por ciento), posterior en 1 (11,1 por ciento) y síndrome de Wilkie con fenómeno cascanueces asociado en 1 (11,1 por ciento). En el 100 por ciento de los casos hubo dolor abdominal o lumbar, asociado a hematuria en 4, orinas espumosas en 4 y varicocele izquierdo en 2 de los 6 varones (33,3 por ciento). Conclusiones: El síndrome de cascanueces debe buscarse en los pacientes que presentan dolor abdominal, lumbar o en flanco izquierdo en forma recurrente, episodios de hematuria recurrente o proteinuria ortostática. En el varón con varicocele izquierdo debe descartarse esta posibilidad. El fenómeno cascanueces, puede diagnosticarse cuando se investiga al paciente por causa no relacionada(AU)

Introduction: Nutcracker syndrome (NCS) is a vascular anomaly which is rarely searched and diagnosed due to its low incidence and because of the difficulty to suspect on it among other frequent clinical manifestations. Objective: To examine clinical and imaging characteristics of patients diagnosed with NCS. Methods: Descriptive, retrospective and prospective study in patients admitted in William Soler University Pediatric Hospital in the period from January, 2013 to December, 2017. When it was suspected the presence of the syndrome, it was made an ultrasound looking for dilation of the left renal vein and the output angle of the superior mesenteric artery. In 7 patients it was made an angio-TAC. The epidemiologic, clinical, laboratory and imaging variables were reviewed. Presentation of cases: From the total of 9 patients diagnosed with a vascular anomaly; 6 (66,7 percent) were males. The mean age was 11,4 years (range 7-15 years). It was diagnosed front NCS in 7 patients (77.7 percent), back NCS in 1 patient (11.1 percent) and Wilkie syndrome with associated NCS in 1 patient (11.1 percent). 100 percent of the cases presented abdominal or lumbar pain related to hematuria (4 patients), foaming urine (4 patients) and left varicocele in 2 of the male patients (33.3 percent). Conclusions: Nutcracker syndrome should be searched in patients presenting frequent abdominal, lumbar or left side pain, recurrent hematuria or orthostatic proteinuria episodes. In males with left varicocele should be discounted this possibility. Nutcracker phenomenon can be also diagnosed when the patient is being investigated due to not related causes(AU)

Prevalence of left renal vein compression (nutcracker phenomenon) signs on computed tomography angiography of healthy individuals.

OBJECTIVE: We evaluated the frequency of significant left renal vein (LRV) compression, also called the nutcracker phenomenon (NCP), in a normal asymptomatic population. METHODS: The present retrospective descriptive anatomic study analyzed the data from high-definition renal computed tomography (CT) angiography of living kidney donors. A total of 324 CT examinations were evaluated for signs of LRV compression, including the beak sign, aortomesenteric angle <41°, LRV diameter ratio ≥4.9, and beak angle ≥32°. The presence of pelvic varicose veins and the left gonadal vein in the proximal and mid-portion (considered dilated if >0.5 cm) were also evaluated. Anthropometric and laboratory (urine erythrocyte count) data were collected from the medical records. Statistical inference was calculated using Fisher's exact test and Student's t test. RESULTS: The mean aortomesenteric angle was 53.1° in women and 58.7° in men (P = .044). The beak sign and beak angle were present in 15.3% and 9.8%, respectively, and both had a greater prevalence in the women (P = .01). An aortomesenteric angle <41° was identified in 30.5%, with a greater prevalence in women (P < .01). The diameter ratio was positive in 0.7% of the cases, with no difference between the sexes. A left gonadal vein >0.5 cm was more prevalent in women in both the proximal and the mid-portions (P < .01). Although analysis stratified by positive criteria (3 or 4) showed no difference between the sexes, a positive correlation was found with younger age (P < .01). The limitations included the absence of a nutcracker syndrome (NCS) population; the lack of a renocaval pressure gradient, because of the need for intervention; the absence of other types of imaging studies, such as duplex ultrasound scan; and the absence of female parity data. CONCLUSIONS: The NCP and NCS CT criteria were present with a high frequency in healthy individuals. Women and younger individuals showed a greater prevalence of compression findings in the aortomesenteric axis. Revision of the current NCP and NCS criteria with a distinct categorization between sex, age, and body mass index is recommended to better evaluate LRV compressive events.

Association Between Left Renal Vein Entrapment and Varicocele Recurrence: A Cohort Study in 3042 Patients.

The recurrence rates after varicocelectomy vary from 0.9% to 32.2%, especially for patients with the left renal vein entrapment (LRVE). This study aims to study the association between LRVE and varicocele recurrence, and to find the risk factors of LRVE. With the design of a cohort study, we included 3042 varicocele patients who would undergo modified inguinal microscope-assisted varicocelectomy (MHMV). 858 (28.21%) patients with LRVE were as the study group, and 2184 (71.79%) patients without LRVE were as the control group. Compared with the control group, BMI was lower (p < 0.001) in study group. Totally, 18 patients had recurrence after surgery, so the recurrence rate was 0.59%. Seventeen patients (1.98%) in study group and 1 patients (0.05%) in control group had recurrence, and significant statistical difference was found between the two groups (p < 0.001). The risk ratio of LRVE for varicocele recurrence is 43.27. In conclusion, the recurrence rate of our MHMV is the lowest (0.59%). There is association between LRVE and varicocele recurrence, and varicocele patients with LRVE have higher probability of recurrence rate after varicocelectomy. BMI could be a risk factor of LRVE. Thus, for varicocele patients, especially those with lower BMI, attentions should be payed to LRVE.

Nutcracker Syndrome: An Update on Current Diagnostic Criteria and Management Guidelines.

BACKGROUND: Nutcracker syndrome (NCS) describes left renal vein compression between the superior mesenteric artery and the aorta. Although uncommon, it is an important diagnosis due to the important morbidity associated with it, including the risk of chronic kidney disease from long-term left renal vein (LRV) hypertension and the risk of LRV thrombosis. METHODS: This article reviews the literature on NCS, particularly with respect to the diagnostic accuracy of different imaging modalities and the success rates, complications, and long-term follow-up data associated with various surgical interventions. RESULTS AND DISCUSSION: The diagnosis of this condition is based on a stepwise work-up with history and clinical examination, followed by Doppler ultrasonography, computed tomography, magnetic resonance imaging, intravascular ultrasound (IVUS) and phlebography with measurement of the renocaval pressure gradient. Management is determined by symptom severity; often symptom resolution occurs following a conservative approach. However, in some cases, surgical management is required, particularly when conservative management is unsuccessful. When it comes to the surgical management of NCS three main pathways exist: open surgery, laparoscopic surgery and endovascular approaches, with the latter 2 becoming increasingly popular due to their minimal invasiveness. Additionally, cases involving the use of robotic surgery in the management of NCS have been reported. CONCLUSION: Despite the rarity of NCS, its recognition and management are important. This article has explored the evidence basis for conservative, medical and surgical options.

Incidental detection of nutcracker phenomenon on multidetector CT in an asymptomatic population: prevalence and associated findings.

OBJECTIVE: To determine the prevalence of nutcracker phenomenon (left renal vein compression by the superior mesenteric artery) and secondary anatomic findings using multidetector computed tomographic (CT) angiography in an asymptomatic population. METHODS: Ninety-nine consecutive CT angiograms for potential renal transplant donors (mean age, 39.0 years; 42 males) without variant renal vein anatomy were reviewed retrospectively. The diameters of the maximal left renal vein, left renal vein between the aorta and superior mesenteric artery, and draining gonadal and lumbar veins were measured. Sex, age, hematuria, proteinuria, and abdominal or flank pain were recorded. RESULTS: Twenty-three patients had 50% to 70% stenosis, and 4 patients had greater than 70% stenosis of the left renal vein. Dilated gonadal and lumbar veins were found in 16 and 28 patients, respectively. Four patients had hematuria. These findings were not significantly associated with left renal vein compression. CONCLUSIONS: Nutcracker phenomenon and dilated veins originating from the left renal vein are common incidental CT findings and nonspecific for the diagnosis of nutcracker syndrome.