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.

BACKGROUND: Mesenteric venous thrombosis (MVT) is a relatively uncommon but potentially lethal condition associated with bowel ischemia and infarction. The natural history and long-term outcomes are poorly understood and under-reported. METHODS: A single-institution retrospective review of noncirrhotic patients diagnosed with MVT from 1999 to 2015 was performed using International Classification of Diseases, Ninth Revision and radiology codes. Patients were excluded if no radiographic imaging was available for review. Eighty patients were identified for analysis. Demographic, clinical, and radiographic data on presentation and at long-term follow-up were collected. Long-term sequelae of portal venous hypertension were defined as esophageal varices, portal vein cavernous transformation, splenomegaly, or hepatic atrophy, as seen on follow-up imaging. RESULTS: There were 80 patients (57.5% male; mean age, 57.9 +/- 15.6 years) identified; 83.3% were symptomatic, and 80% presented with abdominal pain. Median follow-up was 480 days (range, 1-6183 days). Follow-up radiographic and clinical data were available for 50 patients (62.5%). The underlying causes of MVT included cancer (41.5%), an inflammatory process (25.9%), the postoperative state (20.7%), and idiopathic cases (18.8%). Pancreatic cancer was the most common associated malignant neoplasm (53%), followed by colon cancer (15%). Twenty patients (26%) had prior or concurrent lower extremity deep venous thromboses. Most patients (68.4%) were treated with anticoagulation; the rest were treated expectantly. Ten (12.5%) had bleeding complications related to anticoagulation, including one death from intracranial hemorrhage. Four patients underwent intervention (three pharmacomechanical thrombolysis and one thrombectomy). One patient died of intestinal ischemia. Two patients had recurrent MVT, both on discontinuing anticoagulation. Long-term imaging sequelae of portal hypertension were noted in 25 of 50 patients (50%) who had follow-up imaging available. Patients with long-term sequelae had lower recanalization rates (36.8% vs 65%; P = .079) and significantly higher rates of complete as opposed to partial thrombosis at the initial event (73% vs 43.3%; P < .005). Long-term sequelae were unrelated to the initial cause or treatment with anticoagulation (P = NS). CONCLUSIONS: Most cases of MVT are associated with malignant disease or an inflammatory process, such as pancreatitis. A diagnosis of malignant disease in the setting of MVT has poor prognosis, with a 5-year survival of only 25%. MVT can be effectively treated with anticoagulation in the majority of cases. Operative or endovascular intervention is rarely needed but important to consider in patients with signs of severe ischemia or impending bowel infarction. There is a significant incidence of radiographically noted long-term sequelae from MVT related to portal venous hypertension, especially in cases of initial complete thrombosis of the mesenteric vein.

OBJECTIVE: To define the relative importance of fiber type as compared to laser wavelength on tissue injury depth, postoperative pain, and bruising during endovenous laser ablation. METHODS: This study included 213 limbs that were treated with an 810-, 980-, or 1470-nm laser, with bare-tip (BT) or jacket-tip (JT) fibers. Pain scores (10-point scale) and bruising scores (5-point scale) were recorded. Tissue thermal injury depth (mm) was evaluated in vitro for the 810- and 1470-nm wavelengths with BT and JT fibers. RESULTS: The JT fibers had lower pain scores as compared to the BT fibers at 810 nm (1.69 +/- 1.77 vs 3.70 +/- 1.34; P < .0005) and at 980 nm (1.14 +/- 1.06 vs 2.71 +/- 1.80; P < .0005). The JT fibers had lower bruising scores as compared to the BT fibers at 980 nm (0.89 +/- 1.06 vs 2.00 +/- 1.44; P < .0005). The in vitro study showed lower thermal injury depths for the JT as compared to the BT fibers at 810 nm (0.36 mm +/- 0.26 mm vs 1.05 mm +/- 0.34 mm; P < .0005) and at 1470 nm (0.20 +/- 0.16 mm vs 0.71 +/- 0.31 mm; P < .0005). With regard to wavelength, 980-nm laser had lower pain scores as compared to 810-nm laser with BT fibers (2.71 +/- 1.80 vs 3.70 +/- 1.34; P = .015), and with JT fibers, a similar result trended toward significance (1.14 +/- 1.06 vs 1.69 +/- 1.77; P = .057). The 980-nm JT fiber showed less bruising as compared to the 810-nm JT fiber (0.89 +/- 1.06 vs 1.42 +/- 1.19; P = .019). Similarly, the 1470-nm JT fiber showed less bruising as compared to the 810-nm JT fiber (0.94 +/- 1.02 vs 1.42 +/- 1.19; P = .038). The in vitro study showed thermal injury depths that were less for 1470 nm as compared to 810 nm, with JT fibers (0.20 +/- 0.16 mm vs 0.36 +/- 0.26 mm; P = .013) or with BT fibers (0.71 +/- 0.31 mm vs 1.05 +/- 0.34 mm; P =.001). All mean differences between JT and BT fibers were greater than between differing wavelengths. The multivariate analysis for the in vitro study showed a mean difference between 1470 nm and 810 nm of 0.26 mm, P < .0005 favoring 1470 nm and a mean difference between JT and BT fibers of 0.61 mm, P < .0005 favoring the JT fibers. CONCLUSIONS: The use of a JT fiber appeared to be more significant in reducing pain and bruising as compared to a longer wavelength. Moreover, the results appeared additive, and the cohort using 1470 nm with a JT fiber produced the best treatment outcomes. Additional study is required to confirm the efficacy and durability of the various iterations evaluated; however, these data should be taken into consideration when undertaking treatment with endovenous laser ablation.

Forequarter amputation is a radical operation performed for treatment of malignant neoplasms of the shoulder girdle not amenable to limb salvage. Traditional approaches involve bone and soft tissue resection, followed by ligation of the axillary vessels. We describe a technique to minimize blood loss whereby control of the subclavian vessels is performed before amputation of a large tumor associated with extensive venous congestion. A 34-year-old man presented with proximal humeral osteosarcoma. Surgery involved claviculectomy to facilitate vascular control of the subclavian vessels, followed by guillotine amputation at the proximal upper arm level and completion of the amputation as conventionally described.

Although inferior vena cava filter placement is a safe and effective method of reducing the risk of pulmonary embolism, devastating complications can result from thrombosis and migration. Here we present a case of acute renal failure as a result of suprarenal inferior vena cava filter migration and caval thrombosis. We discuss a novel endovascular approach for its management by mechanical aspirational thrombectomy.

Superficial venous incompetence is a common lower limb vascular condition, with venous ulceration representing the most severe sequela of the disease. The treatment of superficial venous incompetence can aid in ulcer healing, and a variety of modalities are available. Successful treatment requires attention to appropriate patient selection and procedural technique.

Tumescent anesthesia refers to the percutaneous administration of large volume anesthetic to cause the target tissue to become swollen or firm. The use of tumescent anesthesia is essential for the treatment of refluxing truncal veins using endothermal technologies. In order to obviate the use of tumescent anesthesia as an adjunct to treatment, one has to evaluate the technologies that do not employ thermal energy as the modality for treatment. These technologies include foam sclerotherapy, mechanicochemical ablation (MOCA), and the use of glue (Sapheon closure system). The following review juxtaposes the literature supporting the use of tumescent-based techniques to the literature supporting the use of tumescent-less techniques.