Automated Quantitative Imaging Measurements of Disease Severity in Patients with Nonthrombotic Iliac Vein Compression.

PURPOSE: An automated segmentation technique (AST) for computed tomography (CT) venography was developed to quantify measures of disease severity before and after stent placement in patients with left-sided nonthrombotic iliac vein compression. MATERIALS AND METHODS: Twenty-one patients with left-sided nonthrombotic iliac vein compression who underwent venous stent placement were retrospectively identified. Pre- and poststent CT venography studies were quantitatively analyzed using an AST to determine leg volume, skin thickness, and water content of fat. These measures were compared between diseased and nondiseased limbs and between pre- and poststent images, using patients as their own controls. Additionally, patients with and without postthrombotic lesions were compared. RESULTS: The AST detected significantly increased leg volume (12,437 cm3 vs 10,748 cm3, P < .0001), skin thickness (0.531 cm vs 0.508 cm, P < .0001), and water content of fat (8.2% vs 5.0%, P < .0001) in diseased left limbs compared with the contralateral nondiseased limbs, on prestent imaging. After stent placement in the left leg, there was a significant decrease in the water content of fat in the right (4.9% vs 2.7%, P < .0001) and left (8.2% vs 3.2%, P < .0001) legs. There were no significant changes in leg volume or skin thickness in either leg after stent placement. There were no significant differences between patients with or without postthrombotic lesions in their poststent improvement across the 3 measures of disease severity. CONCLUSIONS: ASTs can be used to quantify measures of disease severity and postintervention changes on CT venography for patients with lower extremity venous disease. Further investigation may clarify the clinical benefit of such technologies.

Technical Feasibility and Clinical Effectiveness of Transjugular Intrahepatic Portosystemic Shunt Creation in Pediatric and Adolescent Patients.

PURPOSE: To examine the technical feasibility and clinical efficacy of transjugular intrahepatic portosystemic shunt (TIPS) creation in children and adolescents. MATERIALS AND METHODS: Retrospective review was performed of 59 patients (mean age 12.6 y [range, 1.5-20 y], mean weight 47.5 kg [range, 11.4-112.2 kg], mean Model for End-stage Liver Disease/Pediatric End-stage Liver Disease score 12.5 [range, 6-33]) who underwent 61 TIPS attempts at 3 tertiary children's hospitals from 2001 to 2017 for acute esophageal or gastroesophageal variceal bleeding, primary and secondary prevention of variceal bleeding, and refractory ascites. Pediatric liver disease etiologies included biliary atresia, cystic fibrosis, and ductal plate anomalies. Technical, hemodynamic, and clinical success and patency rates were reported at 1, 6, 12, and 24 months. Statistical analysis evaluated reasons for clinical failure. Kaplan-Meier analysis measured clinical success, patency, and transplant-free survival. RESULTS: Technical success was 93.4% (57/61) in 59 consecutive patients. Most common TIPS indications were treating and preventing esophageal and gastroesophageal variceal bleeding (57/59; 96.6%). Hemodynamic success was 94% (47/50). Clinical success was 80.7% (45/56). Two-year clinical success for acute variceal bleeding and ascites was 94.1% and 100%, respectively. Overall patency at 1, 6, 12, and 24 months was 98.0%, 97.8%, 94.3%, and 91.3%. Two-year transplant-free survival was 88.8%. Overall and major complication rates were 21.2% (13/61) and 8.2% (5/61), with 3 mortalities. Gradient reduction < 12 mm Hg correlated with clinical success (P < .01). CONCLUSIONS: TIPS creation in pediatric patients is technically feasible and clinically efficacious for treatment and prevention of esophageal and gastroesophageal variceal hemorrhage. High 2-year clinical success, patency, and survival rates should encourage providers to consider portosystemic shunts as a bridge to liver transplantation.

Quantification of Activity Lost to Delivery-System Residual and Decay in Yttrium-90 Radioembolization.

PURPOSE: To measure the decay activity loss and delivery system residual activity loss of yttrium-90 (Y90) radioembolization treatments across resin and glass microsphere activities. MATERIALS AND METHODS: For Y90 administrations between December 2009 and June 2017 at the study institution, the prescribed activity, prepared activity, and delivered activity were recorded. Six hundred sixty-two administrations were reviewed-345 glass (0.21-8.52 GBq) and 317 resin (0.18-3.28 GBq). Twenty-five patients (all resin) were excluded for arterial stasis or catheter clogging. The percentage and actual losses of activity lost to decay and to delivery system residual were calculated for glass and resin microspheres. RESULTS: The median time between activity premeasurement and administration was 2.20 hours, resulting in a median activity lost to decay of 0.030 GBq or 2.35%, with no significant difference observed between glass and resin despite differences in preparation (P = .0697). Resin showed significantly higher activity lost to delivery system residual than glass (0.039 GBq vs 0.010 GBq, 3.01% vs 0.61%, P < .001). The percent activity lost to residual varied with activity prepared, with a maximum of 20.1% and 16.2% for the smallest activities of resin and glass, respectively. CONCLUSIONS: Residual activity loss differs between glass and resin microspheres. For resin microspheres in particular, percent residual activity loss increases with lower prepared activities. Protocols for activity calculation and preparation, patient dosimetry, and regulatory compliance must take these losses into consideration prospectively.