Nutcracker syndrome: diagnosis and therapy

Nutcracker syndrome (NCS) is an extrinsic compression of the left renal vein (LRV) by the superior mesenteric artery (SMA) anteriorly and aorta posteriorly resulting in renal vascular congestion manifesting as hematuria, proteinuria, orthostatic hypotension, pain, or even renal dysfunction. Long-standing venous compression can encourage collateral drainage pathways through gonadal and pelvic veins, which may explain reported symptom and syndrome overlap with pelvic congestion syndrome. Diagnosis can be challenging and variable, frequently involving a combination of ultrasound Doppler, cross-sectional, and invasive imaging. Often, intravascular pressure measurements are required to prove a renocaval pressure gradient to aid in a definitive diagnosis. Conservative management is appropriate, especially in children, who tend to outgrow the disorder. In the interim, medical management with angiotensin converting enzyme inhibitors (ACEIs) is a useful therapy to manage orthostatic hypotension in the pediatric population. In adults, invasive therapies are more frequently pursued. These are aimed at relieving the extrinsic compression on the LRV. The standard of care is renal vein transposition, with renal autotransplantation reserved for recalcitrant cases. Endovascular stenting is a less invasive option. Laparoscopic placement of an exovascular stent is a newer therapy intended to minimize trauma to the LRV. In this review, we will discuss the clinical manifestations, diagnostic criterion, imaging features, and conservative and surgical therapies for this condition.

Venous thoracic outlet syndrome

Venous thoracic outlet syndrome (vTOS) is a spectrum of disease caused by external compression of the subclavian vein as it passes through the costoclavicular space. Paget-Schroetter's Syndrome (PSS) or effort thrombosis is a subtype of vTOS where compression and microtrauma to subclavian vein from repetitive arm movements results in venous thrombosis. PSS or effort thrombosis mostly affects young otherwise healthy active individuals, and this further highlights the importance of this condition. Early diagnosis and aggressive early intervention aimed at complete resolution of acute symptoms and minimizing the risk of recurrence is ultimately important and increases the likelihood of the full restoration of limb function. Several noninvasive imaging techniques are currently available to confirm the initial diagnosis including Doppler ultrasound, contrast-enhanced computed tomography, and magnetic resonance imaging. Following diagnosis, multiple algorithms exist for the management of PSS and almost all require a multidisciplinary approach. Like any other condition involving the thrombosis of deep venous system, initial step in the management is anticoagulation. Catheter-directed therapies (CDT) have also a pivotal role as the initial treatment to resolve the acute thrombosis and establish venous patency. CDT combined with medical anticoagulation and surgical decompression are the components of most treatment algorithms for the management of patients suffering from PSS.

A systematic review of automated feeder detection software for locoregional treatment of hepatic tumors

PURPOSE

The purpose of this study was to perform a systematic review of current literature describing the efficacy and technical outcomes of transarterial liver therapies using automated feeder detection (AFD) software.

MATERIALS AND METHODS

This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. A structured search was performed in the PubMed, SCOPUS, and Embase databases of patients undergoing locoregional therapy of liver tumors utilizing AFD software. Demographic data, procedure data (including radiometrics) and tumor response rate were recorded. Where available, performance of AFD was compared to conventional digital subtraction angiography (DSA) and cone-beam CT (CBCT) without AFD.

RESULTS

A total of 14 full-text manuscripts met inclusion criteria, comprising 1042 tumors in 604 patients (305 men, 156 women; mean age, 68.6±6.0 [SD] years), including 537 patients with hepatocellular carcinoma, 8 with metastases from neuroendocrine tumors, and 59 patients without reported etiology. Reported sensitivity of AFD ranged between 86% and 98.5%, compared to DSA alone (38% - 64%) or DSA in combination with CBCT (69% - 81%). Three studies reported tumor response by modified response evaluation criteria in solid tumors (mRECIST) guidelines, with complete response in the range of 60% - 69%.

CONCLUSION

AFD is a promising new technology for the identification of intrahepatic and extrahepatic tumor-feeding arteries and should be considered a useful adjunct to conventional DSA and CBCT in the treatment of liver tumors.

Safety and Feasibility of Ultrasound-Guided Gastric Access for Percutaneous Transabdominal Gastrostomy Tube Placement

Background

The aim of the study was to evaluate the safety and feasibility of ultrasound guidance gastric access for percutaneous retrograde transabdominal gastrostomy (G)-tube placement.

Methods

Twenty-eight patients undergoing 31 percutaneous retrograde transabdominal G-tube placements utilizing ultrasound-guided gastric accesses were retrospectively identified.

Results

All patients had successful placement of G tubes with ultrasound-guided gastric access. There were no cases of aspiration or peritonitis. Average fluoroscopy time was 2.7 ± 1.4 min and average radiation dose was 220 ± 202 µGym².

Conclusions

Ultrasound-guided access for gastrostomy placement is safe and feasible and can be performed with minimal fluoroscopy times resulting in low patient and operator radiation dose.

Transcatheter Embolization of Cystic Artery Pseudoaneurysms Secondary to Acute Cholecystitis

Cystic artery pseudoaneurysm is a rare entity most closely associated with trauma to the biliary vasculature (usually iatrogenic) or inflammation from adjacent cholecystitis. Most cases are treated intraoperatively during cholecystectomy. We describe 3 cases of cystic artery pseudoaneurysms secondary to acute cholecystitis, 2 with active hemobilia, treated with transcatheter embolization at our institution.

Endovascular Treatment of a Dorsalis Pedis Artery Pseudoaneurysm

Pseudoaneurysm of the dorsalis pedis artery (DPA) is an extremely rare entity that most commonly occurs secondary to trauma or surgery. All reported cases describe surgical treatment. We illustrate a case of enlarging DPA pseudoaneurysm causing pain and disability in a 49-year-old woman who was treated with transcatheter embolization and pseudoaneurysm aspiration resulting in near-immediate resolution of symptoms.

The MILLER banding procedure as a treatment alternative for dialysis access steal syndrome: a single institutional experience

OBJECTIVE

To describe a single institutional experience with minimally invasive limited ligation endoluminal-assisted revision (MILLER) for treatment of dialysis access steal syndrome (DASS).

MATERIALS AND METHODS

Twenty patients were retrospectively identified that underwent 30 MILLER band procedures for DASS at our institution from March 2010 to December 2014. Technical success was defined by successful creation of MILLER band with preservation of flow for hemodialysis. Clinical success was defined as complete resolution of signs and symptoms with preservation of dialysis access in a 1-month postprocedural period. Primary MILLER band patency, postintervention-assisted primary access patency, and postprocedure secondary access patency are reported.

RESULTS

Technical success was achieved in all patients. Clinical success was achieved in 75% of patients after one banding procedure and in 95% of patients after two banding procedures. One patient experienced access thrombosis following the initial banding procedure which was subsequently treated and did not lead to loss of access. MILLER band patency was 83% at 1 month and 77% at 6 months. Postintervention-assisted primary patency was 95%, 93%, and 92% at 3 months, 6 months, and 1 year, respectively. Postintervention secondary patency was 86%, 68%, and 59% at 3 months, 6 months, and 1 year, respectively.

CONCLUSIONS

MILLER banding offers a less-invasive alternative to surgical therapy that appears to be safe and permits preservation of dialysis access.

Isolation and characterization of Erythrobacter sp. strains from the upper ocean

Seven strains of marine aerobic anoxygenic phototrophs belonging to the genus Erythrobacter were isolated. The strains were characterized regarding their physiological and biochemical properties, 16S rDNA and pufM gene sequences, morphological features, substrate preference, as well as pigment and lipid composition. All strains had functional type-2 reaction centers containing bacteriochlorophyll, served by small, light-harvesting complex 1, and were photosynthetically competent. In addition, large pools of carotenoids were found, but only some of the accessory pigments transfer energy to the reaction centers. All of the isolates were facultative photoheterotrophs. They required an organic carbon substrate for growth; however, they are able to supplement a significant fraction of their metabolic requirements with photosynthetically derived energy.