Posterior nutcracker syndrome

Renal vein compression syndromes are rare causes of hematuria and can be divided into anterior and posterior nutcracker syndrome. When the left renal vein is compressed between the aorta and the superior mesenteric artery it causes anterior nutcracker syndrome. The posterior nutcracker syndrome is very rare and is considered when the left renal vein is compressed between the aorta and vertebral column. Symptoms of nutcracker syndromes may include intermittent left flank pain associated with hematuria, proteinuria, and sometimes with symptoms of pelvic congestion. Diagnosis is often difficult and plan for treatment is always challenging and requires careful evaluation of the patient's history and workup findings. We present a rare case report of a posterior nutcracker syndrome diagnosed in a young lady with long-standing symptoms that required surgical intervention.     

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

Compression of the left renal vein between the aorta and the superior mesenteric artery has been termed the nutcracker syndrome. Obstruction of left renal vein outflow results in venous hypertension with the formation of intra- and extrarenal collaterals and/or the development of gonadal vein reflux. To date, a variety of clinical symptoms due to mesoaortic compression of the left renal vein (nutcracker syndrome) have been described. It is not known what pathophysiological variables play a role in the different clinical manifestations of nutcracker syndrome. We report two patients representing the two different forms of the condition. In the first, hematuria and left flank pain resolved in a young man after successful renocaval reimplantation. In the second, symptoms of pelvic congestion due to pelvic varices improved in a middle-aged woman after successful embolization of the gonadal vein and pelvic collaterals. This report reviews the pathophysiology, presentation, diagnosis including radiographic findings, management options, as well as the current literature on nutcracker syndrome.     

Young woman with nutcracker syndrome without main clinic manifestation: Hematuria—Case report

IntroductionThe nutcracker syndrome occurs due to the compression of the left renal vein between the aorta and the superior mesenteric artery. The diagnosis of the syndrome is often difficult and under diagnosed. The main clinical manifestations are hematuria and pelvic or back pain.Presentation of caseA 25 years old female patient with severe abdominal pain in the lower abdomen without hematuria. Diagnosis with nutcracker syndrome after performing computed tomography. Presented the first episode of pain with 17 years old and was diagnosed at age 25.DiscussionIn the nutcracker syndrome anatomical changes do not generate specific symptoms, causing the disease to be underdiagnosed. In this syndrome, there is increased pressure on the left renal vein, generating several signs and symptoms, and hematuria is one of present. Our patient did not have hematuria. Because of common symptoms, it makes nutcracker syndrome difficult diagnosis, confusing with other diseases, especially with nephrolithiasis. It is usually diagnosed after exclusion of other diseases.ConclusionThe diagnosis of nutcracker syndrome is done after exclusion of other causes of chronic pelvic pain. In most cases, macroscopic and microscopic hematuria are present but was unobserved in this case. Making it more difficult diagnosis.     

Surgical treatment of posterior nutcracker syndrome

Posterior nutcracker syndrome (PNS) is a rare condition due to left renal vein (LRV) hypertension, caused by compression of the LRV between the vertebral column and the abdominal aorta. Diagnosis of PNS is challenging, as symptoms are variable and not specific. Therapeutic options are debated, and either conservative, open, or endovascular approaches have been advocated as both safe and effective. We report our experience with a case of PNS in a 17-year-old woman, who presented with a 2 year history of recurrent hematuria associated to severe left flank and back pain, successfully treated with anterior transposition of the LRV.     

腹腔镜下左肾静脉外支架固定术治疗左肾静脉压迫综合征的临床分析

目的 探讨腹腔镜下左肾静脉外支架固定术治疗左肾静脉压迫综合征的临床疗效.方法 左肾静脉压迫综合征患者5例.男4例,女1例.年龄20～35岁,平均25岁.肉眼血尿3例,活动后加重,合并蛋白尿1例;左腰酸痛伴左精索静脉曲张2例.术前彩色多普勒超声及CT三维血管重建均提示左肾静脉压迫明显.扩张段与受压段直径比值均＞3.膀胱镜检查3例可见左输尿管口喷血尿.5例均于全麻下行腹腔镜下左肾静脉受压段外支架固定术治疗,术中用人造血管固定于下腔静脉与生殖静脉之间形成血管外支架以克服左肾静脉受压.结果 5例手术均顺利完成.手术时间65～70 min,平均67 min.术中出血量10～15 ml,平均13 ml.术中术后无明显外科并发症,术后恢复顺利,术后5～6 d出院.肉眼血尿消失3例,左精索静脉曲张减轻2例.术后随访9～39个月,平均28个月,1例术前肉眼血尿、术后仍有轻微镜下血尿,4例尿常规检查正常.5例其余症状均消失,超声检查示左肾静脉血流通畅、受压现象消失.结论 腹腔镜下左肾静脉外支架固定术采用人造血管环绕左肾静脉抵抗肠系膜上动脉压迫,是治疗左肾静脉压迫综合征的一种可供选择的微创技术,手术简单、方便、安全有效,创伤小、痛苦少、恢复快.     

腹腔镜下左肾静脉外支架固定术治疗左肾静脉压迫综合征的临床分析

目的 探讨腹腔镜下左肾静脉外支架固定术治疗左肾静脉压迫综合征的临床疗效.方法 左肾静脉压迫综合征患者5例.男4例,女1例.年龄20～35岁,平均25岁.肉眼血尿3例,活动后加重,合并蛋白尿1例;左腰酸痛伴左精索静脉曲张2例.术前彩色多普勒超声及CT三维血管重建均提示左肾静脉压迫明显.扩张段与受压段直径比值均＞3.膀胱镜检查3例可见左输尿管口喷血尿.5例均于全麻下行腹腔镜下左肾静脉受压段外支架固定术治疗,术中用人造血管固定于下腔静脉与生殖静脉之间形成血管外支架以克服左肾静脉受压.结果 5例手术均顺利完成.手术时间65～70 min,平均67 min.术中出血量10～15 ml,平均13 ml.术中术后无明显外科并发症,术后恢复顺利,术后5～6 d出院.肉眼血尿消失3例,左精索静脉曲张减轻2例.术后随访9～39个月,平均28个月,1例术前肉眼血尿、术后仍有轻微镜下血尿,4例尿常规检查正常.5例其余症状均消失,超声检查示左肾静脉血流通畅、受压现象消失.结论 腹腔镜下左肾静脉外支架固定术采用人造血管环绕左肾静脉抵抗肠系膜上动脉压迫,是治疗左肾静脉压迫综合征的一种可供选择的微创技术,手术简单、方便、安全有效,创伤小、痛苦少、恢复快.

Abstract：

Objective To report the experience in the use of laparoscopic extravascular stent for the treatment of the nutcracker syndrome. Methods Five patients (4 men and 1 woman) aged 20 to 35 years (mean 25) underwent laparoscopic extravascular stent of the left renal vein (LRV) for treatment of nutcracker syndrome associated with severe recurrent gross hematuria and left gonadal vein varices. All patients met the criteria for establishing the diagnosis of nutcracker syndrome. Ultrasonography, computed tomography, and magnetic resonance imaging revealed visible entrapment of the LRV between the superior mesenteric artery and aorta. Bleeding from the left ureteral orifice was detected by cystoscopy in 3 cases. An externally reinforced graft was selected to form an external stent around the LRV to relieve the compression. Results The mean operation time was 67 min (65-70min). No complications occurred during surgery. The postoperative follow-up was 9 to 39 months (mean 28). Total relief was achieved in 4 men without a relapse of symptoms and abnormalities were not found in urine tests. There was partial relief for the female patient due to microscopic hematuria after the operation. In all the 5 cases, Color Doppler ultrasonography showed that the blood outflow was smooth, the inner diameter and flow velocity of the aortomesenteric portion of the LRV were both decreased, and the gonadal vein varices had diminished in diameter. Conclusions The laparoscopic extravgscular stent of the renal vein could be a feasible approach for re-establishing free renal venous outflow in patients with nutcracker syndrome. This slightly invasive treatment could eliminate the symptoms of the condition.     

腹腔镜下左肾静脉外支架固定术治疗左肾静脉压迫综合征的临床分析

目的 探讨腹腔镜下左肾静脉外支架固定术治疗左肾静脉压迫综合征的临床疗效.方法 左肾静脉压迫综合征患者5例.男4例,女1例.年龄20～35岁,平均25岁.肉眼血尿3例,活动后加重,合并蛋白尿1例;左腰酸痛伴左精索静脉曲张2例.术前彩色多普勒超声及CT三维血管重建均提示左肾静脉压迫明显.扩张段与受压段直径比值均＞3.膀胱镜检查3例可见左输尿管口喷血尿.5例均于全麻下行腹腔镜下左肾静脉受压段外支架固定术治疗,术中用人造血管固定于下腔静脉与生殖静脉之间形成血管外支架以克服左肾静脉受压.结果 5例手术均顺利完成.手术时间65～70 min,平均67 min.术中出血量10～15 ml,平均13 ml.术中术后无明显外科并发症,术后恢复顺利,术后5～6 d出院.肉眼血尿消失3例,左精索静脉曲张减轻2例.术后随访9～39个月,平均28个月,1例术前肉眼血尿、术后仍有轻微镜下血尿,4例尿常规检查正常.5例其余症状均消失,超声检查示左肾静脉血流通畅、受压现象消失.结论 腹腔镜下左肾静脉外支架固定术采用人造血管环绕左肾静脉抵抗肠系膜上动脉压迫,是治疗左肾静脉压迫综合征的一种可供选择的微创技术,手术简单、方便、安全有效,创伤小、痛苦少、恢复快.     

The "nutcracker phenomenon" with orthostatic proteinuria: case reports

The nutcracker phenomenon refers to compression of the left renal vein between the aorta and the superior mesenteric artery. Clinical features are hematuria, abdominal pain, left flank pain, pelvic or scrotal discomfort due to varicocele or ovarian vein syndrome. In this report, 2 patients with orthostatic proteinuria, in whom nutcracker phenomenon was detected as a cause, are presented. One of them had posterior nutcracker with also asymptomatic varicocele that was detected during ultrasonographic examination. Nutcracker phenomenon is a rare but important clinical condition that should be considered in the differential diagnosis of patients with proteinuria and hematuria.     

The left renal entrapment syndrome: diagnosis and treatment

A retrospective analysis was performed to review 20 patients with left renal vein (LRV) entrapment syndrome. All cases were diagnosed based on ultrasonography, magnetic resonance angiography, and renal venography. Technical success was achieved in all patients. Transposition of superior mesenteric artery was performed in three cases, transposition of LRV in two, and stent implantation in the LRV in 15. Stent migration occurred in one case, and stent reimplantation was performed. One case suffered from hematoma after transposition of the superior mesenteric artery, and reoperation was performed. Follow-up was made from 6 months to 6 years after the operation. Abnormalities were not found in the urine test of 18 patients and their symptoms disappeared. Two cases still had microscopic hematuria after exercise. All surgical operations are effective for nutcracker syndrome except excessive invasiveness. Stent may be one of the mainstream therapies because of its minimal invasiveness.     

Left renocaval venous bypass with autologous great saphenous vein for nutcracker syndrome

Nutcracker syndrome results from left renal vein compression by the abdominal aorta and the superior mesenteric artery. The consecutively increased renal venous pressure results in hematuria, proteinuria, flank pain, left-sided varicocele, pelvic congestion, and others. We report a 25-year-old man with nutcracker syndrome who underwent successful left renocaval venous bypass with autologous great saphenous vein. The patient's condition clearly improved, with no clinical relapse after treatment. Ultrasound imaging showed patency of the venous bypass and decreased venous hypertension. This technique is a feasible choice for surgical treatment of nutcracker syndrome, with a low incidence of complications and satisfactory results.     

Endovascular management of nutcracker syndrome after migration of a laparoscopically placed extravascular stent

Nutcracker syndrome results from compression of the left renal vein between the superior mesenteric artery and the aorta, leading to symptoms of hematuria and left flank pain. Management options include endovascular or laparoscopic extravascular stent placement, which is very appealing given the minimally invasive nature of these procedures. We report a case of migration of a laparoscopically placed extravascular stent for nutcracker syndrome that was treated successfully by endovascular stent placement.     

Actitud expectante en el síndrome del cascanueces

Nutcracker syndrome is caused by compression of the left renal vein between the aorta and the superior mesenteric artery where it passes in the fork formed at the bifurcation of these arteries. The phenomenon results in left renal venous hypertension. The syndrome is manifested by left flank and abdominal pain, with or without unilateral haematuria. The nutcracker syndrome has been treated in various ways. We report one case of the syndrome and discuss the place of surveillance in its management.     

Endovenous removal of dislodged left renal vein stent in a patient with nutcracker syndrome

Stent migration and dislodgment is a potential complication after endovenous stenting of the left renal vein (LRV) for nutcracker syndrome. Our purpose is to describe the technique for endovenous removal of such a dislodged stent that was used in a 36-year-old woman with nutcracker syndrome initially treated with renal vein transposition. Recurrent renal vein compression and symptoms developed and a 14 × 20-mm self-expanding stent was placed in the LRV and was noted to be dislodged into the inferior vena cava on the first post-procedure day. Through right internal jugular access, the stent was stabilized by cannulating a cell of the stent using a guide wire and an angled angiographic catheter. A 20Fr sheath was then placed via right femoral vein access into the inferior vena cava. The stent lumen was cannulated from femoral approach and the stent straightened with a stiff wire. An 18-mm angioplasty balloon was then used to capture the stent. The stent was then compressed with two 25-mm loop snares while simultaneously deflating the balloon as it was pulled into the 20Fr sheath and removed. The LRV was restented with an 18 × 40-mm self-expanding stent. Stenting of LRV for nutcracker syndrome can result in stent migration. Endovenous removal of such a dislodged self-expanding stent is feasible. Our technique emphasizes stent stabilization with cell cannulation and capture over a larger diameter balloon.     

The nutcracker syndrome: its role in the pelvic venous disorders.

BACKGROUND: Symptoms of pelvic venous congestion (chronic pelvic pain, dyspareunia, dysuria, and dysmenorrhea) have been attributed to massive gonadal reflux. However, obstruction of the gonadal outflow may produce similar symptoms. Mesoaortic compression of the left renal vein (nutcracker syndrome) produces both obstruction and reflux, resulting in symptoms of pelvic congestion. We describe the diagnosis and management of nine patients studied in our institutions. MATERIALS AND METHODS: From a group of 51 female patients with pelvic congestion symptoms studied at our institutions, there were nine patients with symptoms of pelvic congestion, microscopic hematuria, and left-sided flank pain. The diagnosis of the nutcracker syndrome was suspected based on clinical examination, Doppler scan, duplex ultrasound scan, computed tomography scan, and magnetic resonance imaging. The diagnosis was confirmed by retrograde cine-video-angiography with renocaval gradient determination and catheterization of both internal iliac venous systems. All patients had a renocaval pressure gradient >4 mm Hg (normal, 0-1 mm Hg). Renal compression was relieved by external stent (ES) in two patients, internal stent (IS) in one patient, and gonadocaval bypass (GCB) in three. GCB was preceded by coil embolization of internal iliac vein tributaries connecting with lower-extremity varicose veins in three patients. Three patients deferred surgery and are under observation. Mean follow-up time was 36 months (range, 12-72 months). RESULTS: Hematuria disappeared postoperatively in all patients. ES and IS normalized the renocaval gradient and resulted in significant alleviation of symptoms (90% improvement on a scale of 0-10 where 0 = no improvement and 10 = greatest improvement). Two patients with GCB had a residual gradient of 3 mm Hg. The third patient normalized the gradient. In this group, improvement of symptoms was 60%. Patients awaiting surgery are being treated conservatively (elastic stockings, hormones, and pelvic compression). They have shown only moderate improvement. CONCLUSION: The nutcracker syndrome should be considered in women with symptoms of pelvic venous congestion and hematuria. The diagnosis is suspected by compression of the left renal vein on magnetic resonance imaging or computed tomography scan and confirmed by retrograde cine-video-angiography with determination of the renocaval gradient. Internal and external renal stenting as well as gonadocaval bypass are effective methods of treatment of the nutcracker syndrome. IS and ES were accompanied by better results than GCB. Surgical and radiologic interventional methods should be guided by the clinical, radiologic, and hemodynamic findings.     

Nutcracker syndrome. Report of a case and review of the literature

Nutcracker syndrome is caused by compression of left renal vein between the aorta and the superior mesenteric artery. This phenomenon results in left renal venous hypertension, left gonadal vein varices and unilateral hematuria. We report a typical case of nutcracker syndrome and we review the literature in an effort to explain this pathology.     

Endovascular stenting in the treatment of pelvic vein congestion caused by nutcracker syndrome: lessons learned from the first five cases

BACKGROUND: Compression of the left renal vein between the aorta and the superior mesenteric artery is a rare but possibly underestimated condition. Surgical correction (42 cases reported in the literature) can be performed by means of a variety of different techniques. Although endovascular stenting is well accepted for iliocaval occlusive disease, it has been poorly evaluated in this indication. We describe five patients who were treated for nutcracker syndrome by using stenting and analyze the nine cases previously reported. METHODS: From November 2002 to September 2004, five women (mean age, 34.7 years) were admitted for endovascular treatment of a nutcracker syndrome. They all had incapacitating pelvic congestion syndrome, including two with a history of left ovarian vein embolization; moreover, two had left lumbar pain, and three had hematuria. The mean preoperative venous disability score was 2.4. The patients underwent a gynecologic examination and laparoscopy to eliminate other causes of pelvic pain. The laparoscopy revealed large pelvic varicose veins and no signs of endometriosis. Duplex scan, computed tomographic scan, and iliocavography revealed left renal vein compression, with proximal distention and collateral pathways, with dilatation and permanent reflux in the left ovarian vein in the three patients who had not had prior embolization. The mean renocaval pullback gradient was 4.3 mm Hg. A percutaneous endovascular procedure, during in which a self-expanding metallic stent was implanted, was performed under general anaesthesia. RESULTS: Technical success was achieved in all cases. One case of stent migration occurred: the stent was pulled down in the inferior vena cava, with uneventful follow-up (mean, 14.3 months). One month later, patients were all improved and stents were patent at the duplex scan examination, without restenosis. The mean venous disability score was 1. No further left ovarian vein reflux was evident at duplex scan in patients who did not have prior embolization. Pelvic pain recurred in one patient who had initially improved, and endometriosis was diagnosed 15 months after the procedure. Two other patients, who received 40-mm-long stents, had a secondary recurrence of the symptoms caused by stent dislodgement. The two other patients were asymptomatic. CONCLUSIONS: This study shows that stenting is feasible, but some guidelines should be followed, mainly the use of long stents protruding into the inferior vena cava. Stenting can eliminate the symptoms of the condition, and the technique is only very slightly invasive. Further experience and follow-up are needed before accepting such a procedure for treatment of the nutcracker syndrome.     

Transperitoneal laparoscopic left gonadal vein ligation can be the right treatment option for pelvic congestion symptoms secondary to nutcracker syndrome

The nutcracker phenomenon refers to compression of the left renal vein at the origin of the superior mesenteric artery and is often underdiagnosed. This can cause symptoms of pelvic venous congestion with retrograde venous flow and a dilated gonadal vein. Here we describe a case in a 39-year-old female, who following imaging investigations to confirm the diagnosis, underwent transperitoneal laparoscopic ligation of the left gonadal vein. Laparoscopic sterilization was also performed with the aid of the gynecologists. Multiparous women, who are more likely to develop pelvic congestion symptoms, more commonly request sterilization and thus we propose that a dual laparoscopic procedure in these cases could be the treatment of choice.     

Intra-arterial digital subtraction angiography for children with idiopathic renal bleeding: a diagnosis of nutcracker phenomenon

Among children with asymptomatic hematuria, 28 cases of nonglomerular idiopathic renal bleeding were subjected to this series of study. Intra-arterial digital subtraction angiography (DSA) and/or renal venography were performed to investigate the hematuria of unknown etiology. DSA clearly demonstrated the entrapment of the left renal vein (LRV), or nutcracker phenomenon in the majority of our patients (22 out of 28 cases): obstruction of the LRV with well-developed collaterals were found in 8 cases, and in the remaining 14 cases, various degrees of LRV compression were demonstrated. A characteristic real-time DSA image was the congestion of LRV associated with collaterals and/or intermittent venous flow at the compressed segment of LRV. The pullback pressures from LRV to the inferior vena cava (IVC) that were obtained from 5 of these patients demonstrated gradients of 2 mmHg (3 cases), 3 mmHg (1 case), and 5 mmHg (1 case), respectively. The parallel application of ultrasonography has given positive signs for LRV entrapment, although they have not necessarily coincided with the existing criteria of nutcracker phenomenon. Considering the high incidence of LRV entrapment among children with nonglomerular hematuria, most nutcracker phenomenon should be diagnosed on ultrasonography. However, intra-arterial DSA is an important tool to establish the disease entity and ultrasonic criteria.     

"胡桃夹症"临床症状和影像学表现的探讨(附13例报告)

目的：提高对“胡桃夹症”的诊断水平。方法：回顾性分析13例“胡桃夹症”患者的临床资料。结果：10例首发症状为血尿，2例首发症状为左侧阴囊内蚯蚓状肿物，以左侧精索静脉曲张就诊，1例首发症状为蛋白尿。1例女性患者伴月经量增大。男性患者均有左侧精索静脉曲张。血管多普勒超声提示左肾静脉通过腹主动脉和肠系膜上动脉之间有受压征象，径线1．6～6．1inin，平均2．64mm。肾门静脉段呈增粗改变，径线7．1～21．0mm，平均10．9mm。增强CT扫描横断面可见腹主动脉和肠系膜上动脉之间挤压左肾静脉，矢状面可见肠系膜上动脉与腹主动脉成锐角，其间的通道变窄。2例肾静脉造影提示左肾静脉过腹主动脉和肠系膜上动脉段处变窄。4例膀胱镜检查可见左侧输尿管口喷血。结论：血尿、蛋白尿、左侧精索静脉曲张是“胡桃夹症”的重要临床症状。多普勒超声、CT是“胡桃夹症”重要的无创性诊断方法。