Faculty Bibliography

OBJECTIVES: Nutcracker syndrome, or mesoaortic compression of the left renal vein (LRV), with associated symptoms related to venous hypertension in the left kidney, is a rare entity that may result in severe symptoms requiring operative intervention. We report on three patients who presented with nutcracker syndrome, including one patient with a circumaortic LRV resulting in posterior nutcracker syndrome, who underwent successful endovascular treatment with renal vein stenting. A review of existing literature on endovascular management of nutcracker syndrome follows. METHODS: Three women (age range 28 to 43 years) presented with symptoms and imaging studies consistent with nutcracker syndrome. Symptoms included pelvic and flank pain in all three patients, and episodes of hematuria in two. Imaging studies demonstrated compression of the LRV between the superior mesenteric artery and aorta in two of the patients. The third patient was noted to have a circumaortic LRV. RESULTS: All three patients underwent venography and LRV stenting. Stents included a 12 x 40 mm self-expanding nitinol stent, 14 x 60 mm Wallstent, and 16 x 40 mm Wallstent. All patients were placed on clopidogrel post-operatively. The duration of follow-up ranged from six to twenty-seven months. At follow up, all three patients reported significant symptomatic improvement, and duplex ultrasonography demonstrated stent patency in all. CONCLUSIONS: Nutcracker syndrome is a rare condition that can be successfully treated with renal vein stenting via an endovascular approach. Results are encouraging at follow-up periods beyond two years.

INTRODUCTION:: Iatrogenic arterial injury is an uncommon but recognized complication of posterior spinal surgery. The spectrum of injuries includes vessel perforation leading to hemorrhage, delayed pseudoaneurysm formation, and threatened perforation by screw impingement on arterial vessels. Repair of these injuries traditionally involved open direct vessel repair or graft placement, which can be associated with significant morbidity. METHODS:: We identified five cases of iatrogenic arterial injury during or after posterior spinal surgery between July 2004 and August 2009 and describe the endovascular treatment of these five patients. RESULTS:: In two patients, intraoperative arterial bleeding was encountered during posterior spinal surgery. The posterior wounds were packed, temporarily closed, and the patients were placed supine. Angiography in both patients demonstrated arterial injury necessitating repair. Covered stent grafts were deployed through femoral cutdowns to exclude the areas of injury. In three additional patients, postoperative computed tomography imaging demonstrated pedicle screws abutting or penetrating the thoracic or abdominal aorta. In all three patients, angiography or intravascular ultrasound (IVUS), or both, confirmed indention or perforation of the aorta by the screw. Aortic stent graft cuffs were deployed through femoral cutdowns to cover the area of aortic contact before hardware removal. All five patients did well and were discharged home in good condition. CONCLUSIONS:: Endovascular repair of arterial injuries occurring during posterior spine procedures is feasible and can offer a safe and less invasive alternative to open repair

Endovenous laser ablation (EVLA) and radiofrequencey ablation have become the procedures of choice for the treatment of superficial venous insufficiency. Their minimally invasive technique and safety profile when compared with operative saphenectomy have led to this change. As EVLA has replaced saphenectomy as the procedure of choice, the distribution of complications has changed. We evaluated the most common and most devastating complications in the literature including burns, nerve injury, arterio-venous fistula (AVF), endothermal heat-induced thrombosis and deep venous thrombosis. The following review will discuss the most frequently encountered complications of treatment of superficial venous insufficiency using EVLA. The majority of the complications described can be avoided with the use of good surgical technique and appropriate duplex ultrasound guidance. Overall, EVLA has an excellent safety profile and should be considered among the first line for treatment of superficial venous reflux.

Background: The treatment of venous insufficiency using endovenous laser ablation or radiofrequency ablation may result in endothermal heat induced thrombosis (EHIT), a form of deep venous thrombosis. This study sought to assess the effect of ablation distance peripheral to the deep venous system on the incidence of EHIT. Methods: This study was a retrospective review of a prospectively maintained database from 4/2007 to 7/2011. Consecutive patients undergoing great saphenous vein (GSV) or small saphenous vein (SSV) ablation were evaluated. Previous to 2/2011, all venous ablations were performed 2cm peripheral to the saphenofemoral or saphenopopliteal junctions (Group I). Subsequent to 2/2011, ablations were performed 2.5cm peripheral to the respective deep system junctions (Group II). The primary outcome was the development of EHIT II or greater, i.e. thrombus protruding into the deep venous system. Secondary outcomes included procedure-site complications such as hematomas and saphenous nerve injury. Chi-square tests were performed for all discrete variables, and unpaired Students t-tests were performed for all continuous variables. P<.05 was considered statistically significant. Results: A total of 3,526 procedures were performed, Group I (N=2672) and Group II (N=854). General demographics and CEAP classification did not differ significantly between the two groups. EHIT demonstrated a trend towards diminished frequency in Group II (Group I: 2.8% vs Group II: 1.6%, P=.077). There were no reported cases of EHIT III or IV in this patient cohort. Patients in Group I were treated using anticoagulation 56% of the time, and patients in Group II were treated using anticoagulation 100% of the time. The frequency of procedure site complications was low and did not differ significantly between the two groups. Conclusions: This study suggests that changing the treatment distance from 2cm to 2.5cm peripheral to the deep venous junction may result in a diminished incidence of EHIT. Ongoing evaluation is required to validate these results and to reaffirm the durability of the technique

In 2001, the use of endovenous laser ablation (EVLA) was introduced to the United States to treat superficial venous insufficiency. EVLA has subsequently undergone a rapid rise in popularity and usage with a concomitant decrease in traditional operative saphenectomy. Since its inception, the use of EVLA to treat superficial venous insufficiency has advanced significantly. The efficacy of treatment has been validated using both hemoglobin-specific laser wavelength and water-specific laser wavelength lasers. Currently, laser optimization is focusing on reducing postprocedural sequelae. The clinical parameters that correlate best with improved postoperative recovery use lower power/energy settings, water-specific laser wavelength lasers, and jacket or radial-emitting tips. Future study is still required to assess the durability of treatment at lower power and energy settings coupled with jacket or radial-emitting tip fibers. Long-term follow-up using duplex imaging is recommended to ensure persistent treatment success

Cystic adventitial disease (CAD) is a well described disease entity that commonly affects the popliteal artery, presenting as a rare cause of non-atherosclerotic claudication. The traditional surgical approaches are cyst resection and bypass, or cyst evacuation or aspiration. We report the case of a 58-year-old female with CAD of the popliteal artery treated successfully with cyst resection and bypass using an autologous graft. We reviewed the literature over the last 25 years on management and outcomes of CAD of the popliteal artery. We identified a total of 123 cases; most cases were treated using a traditional repair, while 3 cases used an endovascular approach. The overall success rate using bypass was 93.3%, compared to 85% in the evacuation/aspiration cohort. All cases treated endovascularly resulted in failure. While no consensus exists regarding the preferred modality to treat CAD, we believe that resection of the cyst and bypass affords the best outcomes