Dmitry Rabkin

Microcoil Embolization for Acute Lower Gastrointestinal Bleeding

PurposeTo assess outcomes after microcoil embolization for active lower gastrointestinal (GI) bleeding.MethodsWe retrospectively studied all consecutive patients in whom microcoil embolization was attempted to treat acute lower GI bleeding over 88 months. Baseline, procedural, and outcome parameters were recorded following current Society of Interventional Radiology guidelines. Outcomes included technical success, clinical success (rebleeding within 30 days), delayed rebleeding (>30 days), and major and minor complication rates. Follow-up consisted of clinical, endoscopic, and pathologic data.ResultsNineteen patients (13 men, 6 women; mean age ± 95% confidence interval = 70 ± 6 years) requiring blood transfusion (10 ± 3 units) had angiography-proven bleeding distal to the marginal artery. Main comorbidities were malignancy (42%), coagulopathy (28%), and renal failure (26%). Bleeding was located in the small bowel (n = 5), colon (n = 13) or rectum (n = 1). Technical success was obtained in 17 patients (89%); 2 patients could not be embolized due to vessel tortuosity and stenoses. Clinical follow-up length was 145 ± 75 days. Clinical success was complete in 13 (68%), partial in 3 (16%), and failed in 2 patients (11%). Delayed rebleeding (3 patients, 27%) was always due to a different lesion in another bowel segment (0 late rebleeding in embolized area). Two patients experienced colonic ischemia (11%) and underwent uneventful colectomy. Two minor complications were noted.ConclusionMicrocoil embolization for active lower GI bleeding is safe and effective in most patients, with high technical and clinical success rates, no procedure-related mortality, and a low risk of bowel ischemia and late rebleeding.

Fracture and migration of a suprarenal inferior vena cava filter in a pregnant patient.

Placement of retrievable inferior vena cava (IVC) filters as prophylaxis for pulmonary embolism (PE) is an increasingly attractive option for patients who require temporary IVC filtration. However, experience thus far with retrievable filters in pregnant patients is limited. This report describes a suprarenally placed Recovery IVC filter in a pregnant woman with PE despite therapeutic anticoagulation. After failed induction of labor and uneventful cesarean section, the patient returned for filter retrieval 167 days after initial placement. Fracture and inferior migration of the filter was observed, and subsequent attempts at filter retrieval were unsuccessful.

Thoracic Duct Embolization and Disruption for Treatment of Chylous Effusions: Experience with 105 Patients

PURPOSE To review the indications, technical approach, and clinical outcomes of thoracic duct embolization (TDE) and thoracic duct disruption (TDD) in patients with symptomatic chylous effusions. MATERIALS AND METHODS A total of 105 patients who underwent 120 consecutive TDE/TDD procedures were retrospectively reviewed. Data including cause of effusion, procedural technique, and pre- and postprocedural effusion volume were analyzed. Technical and clinical success were evaluated for each procedure, with technical success defined as successful interruption of the thoracic duct by embolization or needle disruption and clinical success defined as resolution of effusion without surgical intervention. RESULTS The technical success rate was 79% (95 of 120); 53 TDEs were performed, resulting in a 72% clinical success rate (n = 38), whereas 42 TDDs showed a 55% clinical success rate (n = 23; P = .13). Procedures to treat postpneumonectomy chylous effusions had a success rate of 82% (14 of 17), compared with 47% (nine of 19) in postpleurectomy subjects (P < .05). Clinically successful cases had lower 24-, 48-, and 72-hour postprocedural effusion volumes versus clinically unsuccessful cases (P < .05), as well as greater rates of reduction in effusion volume at these time points (P < .05). Clinical success rate in subjects with traumatic effusions was higher than in subjects with nontraumatic effusions (62% [60 of 97] vs 13% [one of eight]; P < .05), and 6.7% of subjects (n = 7) experienced minor complications. CONCLUSIONS TDE and TDD are safe and effective minimally invasive treatments for traumatic thoracic duct injuries. In the present series, factors affecting procedural success included etiology of effusion, postprocedural effusion volume, and rate of postprocedural effusion volume reduction.

Nitinol Properties Affecting Uses in Interventional Radiology

NITINOL is gaining increasing popularity among the manufacturers of endoluminal devices. At the same time, most interventional radiologists know little about its unique properties. A thorough understanding of the physical properties of nitinol, however, is important for optimizing selection and deployment of endoluminal devices in a given clinical scenario. This article reviews the unique physical characteristics of nitinol that influence its use in interventional radiology. This information is intended to aid in the selection of nitinol-based interventional devices and provide better understanding of technical aspects of their deployment and mechanism of action after implantation.

Transarterial and Transvenous Embolotherapy of Arteriovenous Fistulas in the Transplanted Pancreas

Arteriovenous fistula (AVF) is a rare but well-documented complication of pancreatic allotransplantation. Small, tortuous vessels in the head of the transplanted pancreas may complicate transarterial embolization. The authors recently encountered two women who developed clinical pancreatitis after right pelvic transplant placement with documented AVF in the head of the transplanted pancreas. In the first patient, embolization was successfully performed transarterially. In the second patient, transarterial embolization was not feasible due to the small caliber and extreme tortuosity of the pancreaticoduodenal arcade and transvenous embolic occlusion was successfully performed. Both patients recovered with normalization of enzyme levels and pain reduction.

Postembolization syndrome: changes in white blood cell counts immediately after uterine artery embolization.

Postembolization syndrome (PES) after transcatheter uterine artery embolization (UAE) is classically described as including self-limited pain, nausea, vomiting, and fever. However, the expected components of PES after UAE might also include leukocytosis, the incidence and magnitude of which have not yet been determined. A retrospective review of 78 patients who underwent elective UAE for symptomatic leiomyomas showed an increase in white blood cell (WBC) counts within 24 hours after the procedure in 86% of patients, with clinically defined leukocytosis (WBC count >11,000/microL) present in 21% of patients. Interventional radiologists and other clinicians involved in the care of these patients should expect such changes and not be alarmed regarding early infectious complications.

Reinsertion of Accidentally Dislodged Catheters through the Original Track: What is the Likelihood of Success?

PURPOSE To determine the success rate for reinsertion of interventional radiology-placed catheters that were accidentally removed by using the existing percutaneous track and to investigate factors that influence success rate. MATERIALS AND METHODS The authors performed a retrospective analysis of 225 patients who presented with dislodged catheters (24 tunneled central venous catheters, 170 gastrostomy/jejunostomy tubes, 25 nephrostomy catheters, five biliary catheters, and one transhepatic hemodialysis catheter) and underwent attempts for reinsertion between 1999 and 2007. Data obtained from the radiology information system included the type of catheter and the indwelling and reinsertion times. RESULTS The overall success rate for reinsertion was 87%. Success of reinsertion was associated with longer catheter indwelling times compared to patients who failed reinsertion (254 vs 100 days, P < .01). Success of reinsertion was associated with shorter reinsertion times compared to patients who failed reinsertion (1.1 vs 2.7 days, P < .05). CONCLUSIONS Reinsertion of catheters by using the cutaneous track can be performed successfully during the first days after dislodgement. Success rates vary on the basis of catheter type and indwelling and reinsertion times.

Safety and Utility of Transjugular Liver Biopsy in Hematopoietic Stem Cell Transplant Recipients

PURPOSE Hematopoietic stem cell transplant (HSCT) recipients are at high risk in the setting of percutaneous liver biopsy as a result of comorbid coagulopathy and ascites, and are commonly referred to undergo transjugular liver biopsy. The present study was performed to assess the safety and utility of transjugular liver biopsy in HSCT recipients and to analyze the correlation between corrected hepatic sinusoidal pressure gradient (CHSPG) and pathologic diagnoses. MATERIALS AND METHODS Data from reports of transjugular liver biopsy procedures, pathology reports, and laboratory values of 141 consecutive HSCT recipients who underwent transjugular liver biopsy with pressure measurement between January 2005 and August 2011 in a single institution were retrospectively reviewed and analyzed. RESULTS A total of 166 biopsy procedures were performed in 141 patients. Technical success rate was 98.8%. Biopsy was diagnostic in 95.7% of patients. There were three major complications (1.8%), including one death. CHSPG in patients with venoocclusive disease (VOD) was significantly higher (P<.001) than in those without VOD (16.2 mm Hg±9.2 vs 5.6 mm Hg±3.7). A CHSPG of 10 mm Hg or higher was 90.8% specific and 77.3% sensitive for VOD. CONCLUSIONS The present data show that transjugular liver biopsy is a relatively safe procedure that provides important information for the clinical management of patients with HSCT. Measurement of CHSPG during the procedure can support the diagnosis of VOD.

CT demonstration of a rapidly growing transitional cell carcinoma of the ureter and renal pelvis

Transitional cell carcinoma (TCC) is the most common urothelial malignancy. We present a case of an exceptionally aggressive TCC involving the renal pelvis and ureter. To our knowledge, an upper tract TCC of such rapid growth has not been reported.

Impact of Unilateral Common Iliac Vein Occlusion on Trapping Efficacy of the Greenfield Filter: An in Vitro Study☆

RATIONALE AND OBJECTIVES The purpose of this study was to assess the effect of unilateral common iliac vein occlusion on the capturing efficacy of the Greenfield filter in vitro. MATERIALS AND METHODS A stainless steel over-the-wire Greenfield filter was placed in the Silastic inferior vena cava module of a pulsatile circuit. Three 30-mm blood clots in sets of five were injected through the modules right iliac limb with the circuit in four experimental conditions: vertical position, both iliac limbs patent (VP); vertical position, left iliac limb occluded (VOC); horizontal position, both iliac limbs patent (HP); and horizontal position, left iliac limb occluded (HOC). Each experiment was repeated 15 times, resulting in 75 clots per condition and a total of 300 clot introductions. RESULTS Clot trapping efficacy was 36 of 75 (48%) for VP, 41 of 75 (55%) for VOC, 32 of 75 (43%) for HP, and 26 of 75 (35%) for HOC. Cross comparisons of the four conditions revealed a marginally significant difference (P = .0138 with a corrected test-wise alpha = .0125) only between horizontal and vertical positions with unilateral common iliac limb occlusion. CONCLUSION Unilateral common iliac vein occlusion decreases the capturing efficacy of the Greenfield filter in the horizontal position in vitro. In patients with unilateral common iliac vein occlusion, use of inferior vena cava filters with higher capturing efficacy may be considered.