Third Crystalline Form of P(NDI2OD-T2) with Pronounced End-on Texture.

We report the observation of a third crystalline polymorph, "form III", of the well-studied electron-transporting conjugated polymer P(NDI2OD-T2) that exhibits end-on texture. This third polymorph of P(NDI2OD-T2) is distinguished from other polymorphs by having two monomer units incorporated along the backbone-stacking direction, resulting in a doubling of the c axis of the unit cell. Form III crystallites are realized by melt-annealing a thin film followed by slow cooling. The distinct packing of this third polymorph is established through the application of grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements combined with peak simulation of candidate unit cells. The discovery of a third polymorph of P(NDI2OD-T2) provides a fresh opportunity for studying structure/function relationships of this important semiconducting polymer.

Percutaneous closure of right coronary to superior vena cava fistula.

Coronary artery to superior vena cava (SVC) fistula is a very rare congenital anomaly of the heart. It typically follows the course of sinoatrial-nodal branch. It can originate from the right coronary or circumflex artery. In the majority of cases, it terminates in the SVC close to the right atrium junction. Only five cases were treated in literature successfully through a transcatheter approach. We present a case with a symptomatic right coronary artery to SVC fistula treated with a unique percutaneous embolization using a guidewire loop/balloon occlusion technique. Controlled access and embolization of the fistula was achieved by through-and-through guidewire access across the coronary fistula from the arterial groin access to the venous groin access with balloon occlusion of the coronary artery fistula while detachable coils were positioned.

Fistulojejunostomy Versus Distal Pancreatectomy for the Management of the Disconnected Pancreas Remnant Following Necrotizing Pancreatitis.

BACKGROUND: A disconnected distal pancreas (DDP) remnant is a morbid sequela of necrotizing pancreatitis. Definitive surgical management can be accomplished by either fistulojejunostomy (FJ) or distal pancreatectomy (DP). It is unclear which operative approach is superior with regard to short- and long-term outcomes. METHODS: Between 2002 and 2014, patients undergoing either FJ or DP for DDP were retrospectively identified at a center specializing in pancreatic diseases. Patient demographics, perioperative, and postoperative variables were evaluated. RESULTS: Forty-two patients with DDP secondary to necrotizing pancreatitis underwent either a FJ (n = 21) or DP (n = 21). Between the two cohorts, there were no significant differences in overall lengths of stay, pancreatic leak rates, or readmission rates (all p > 0.05). DP was associated with higher estimated blood loss, increased transfusion requirements, and worsening endocrine function (all p < 0.05). At a median follow-up of 18 months, four patients that underwent a FJ developed a recurrent fluid collection requiring re-intervention. Overall, FJ was successful in 80% of patients as compared to a 95% success rate for DP (p = 0.15). CONCLUSIONS: Although DP was associated with higher intraoperative blood loss, increased transfusion requirements, and worsening of preoperative diabetes, this procedure provides superior long-term resolution of a DDP when compared to FJ.

Routine use of U-tube drainage for necrotizing pancreatitis: a step toward less morbidity and resource utilization.

BACKGROUND: A U-tube drainage catheter (UTDC) is a novel intervention for necrotizing pancreatitis, with multiple benefits: bidirectional flushing, greater interface with large fluid collections, less risk of dislodgement, and creation of a large-diameter fistula tract for potential fistulojejunostomy. We report the first clinical experience with UTDC for necrotizing pancreatitis. METHODS: From 2011 to 2014, all patients undergoing UTDC for necrotizing pancreatitis at our institution were identified. Clinical variables including patient, disease, and intervention-specific characteristics as well as long-term outcomes populated our dataset. RESULTS: Twenty-two patients underwent UTDC for necrotizing pancreatitis; the median follow-up was 10.2 months. Necrotizing pancreatitis was most commonly owing to gallstones (n = 9; 41%), idiopathic disease (n = 5; 23%), and alcohol abuse (n = 4; 18%). During the course of UTDC and definitive operative therapy (when required), patients had median hospital stays of 31 days, 6 interventional radiology procedures, and 6 CT scans. Operative intervention was not necessary in 9 patients (41%). Among the other 13 patients, 4 patients underwent distal pancreatectomy/splenectomy, 8 had a fistulojejunostomy performed, and 1 underwent both procedures. CONCLUSION: UTDC for necrotizing pancreatitis patients is associated with effective drainage and low morbidity/hospital resource utilization. With skilled interventional radiologists and multidisciplinary coordination, this technique is a valuable means of minimizing morbidity for patients with necrotizing pancreatitis.

Varicocele retrograde embolization with boiling contrast medium and gelatin sponges in adolescent subjects: a clinically effective therapeutic alternative.

PURPOSE: Varicoceles occur in approximately 15% of adolescent male subjects and may impair future fertility. The present study describes a varicocele treatment technique involving percutaneous retrograde embolization with boiling hot contrast medium and gelatin sponge pledgets. MATERIALS AND METHODS: A retrospective review of medical records and imaging of all patients who underwent percutaneous retrograde varicocele embolization from 2005 to 2010 was performed. Pre- and postembolization symptoms, physical findings, and ultrasound findings were documented. Fifteen patients (16 embolizations) were identified, with an average age of 15.9 years (range, 12-18 y). Nine were referred because of persistent varicocele after surgical ligation. Three had grade 2 and nine had grade 3 varicoceles. Two had grade 1 varicoceles; one was painful and one was associated with poor semen quality. One varicocele was not clinically evident, but was associated with persistently decreased testicular size. Nine patients had pain or discomfort, and six had no discomfort. Clinical resolution was defined by a combination of symptom resolution and a lack of physical examination findings of varicocele or findings of treated varicocele. RESULTS: Fifteen of the 16 embolizations (94%) were technically successful. Clinical resolution was documented in 14 of 15 patients (95%); one patient experienced a recurrence at 30 months, which was successfully reembolized. One patient experienced temporary paresthesia of the left thigh. There were no major postprocedural complications. Mean follow-up duration was 11 months. CONCLUSIONS: Retrograde embolization of varicoceles in adolescent subjects with the use of boiling hot contrast medium and gelatin sponges is a promising technique that appears effective.

Where there is blood, there is a way: unusual collateral vessels in superior and inferior vena cava obstruction.

Obstruction of the superior vena cava (SVC) or inferior vena cava (IVC) is most commonly an acquired condition, typically caused by malignancy, benign conditions such as mediastinal fibrosis, and iatrogenic causes such as venous catheterization. In the event of chronic occlusion, collateral pathways must develop to maintain venous drainage. The major collateral pathways seen with SVC or IVC obstruction are well described and include the azygos-hemiazygos, internal and external mammary, lateral thoracic, and vertebral pathways. In addition, several unusual collateral pathways may be seen with SVC or IVC obstruction; these include systemic-to-pulmonary venous, cavoportal, and intrahepatic collateral pathways. In patients with systemic-to-pulmonary venous collateral vessels, the systemic veins drain directly into the left side of the heart, resulting in a right-to-left shunt. The collateral veins consist of mediastinal connections between the innominate veins and the superior pulmonary veins through bronchial venous plexuses around the airways, hilar vessels, and pleura. The cavoportal collateral pathways consist of collateral formation between the SVC or IVC and a tributary to the portal system. They include the caval-superficial-umbilical-portal pathway, caval-mammary-phrenic-hepatic capsule-portal pathway, caval-mesenteric-portal pathway, caval-renal-portal pathway, caval-retroperitoneal-portal pathway, and intrahepatic cavoportal pathway. These types of collateral pathways may result in unusual enhancement patterns in the liver. An understanding of these unusual collateral pathways is essential in a patient with caval occlusion who presents with signs and symptoms of a right-to-left shunt or has unusual enhancing lesions in the liver.

Embolization of an arterioportal fistula by injection of D-stat into the portal venous outflow.

Arterioportal fistulas may occur in liver transplant recipients after percutaneous biopsy. This report describes a case in which a 13-year-old liver transplant patient developed an arterioportal fistula after multiple liver biopsies and underwent coil embolization; however, at that time, there were at least two small arterial feeders that were not amenable to subselection. He later developed recurrent variceal bleeding, and repeat angiogram revealed multiple tiny serpentine feeding arteries. Because these arteries could not be subselectively catheterized, the collagen-thrombin mixture, D-Stat, was used to occlude the portal venous outflow of the arterioportal fistula. Subsequent angiography demonstrated successful complete occlusion of the arterioportal fistula.

Biliary duct ablation with N-butyl cyanoacrylate.

PURPOSE: To assess the efficacy of percutaneous insertion of n-butyl cyanoacrylate (NBCA) in the ablation of bile ducts in patients with persistent postsurgical bile leaks in which traditional means of treatment have failed. MATERIALS AND METHODS: Ablation of bile ducts with NBCA was performed in six patients (two men and four women). The average length of follow-up was 27 months (range, 13-46 months). Four patients presented after hepatic lobectomy with a persistent bile leak, one patient presented after cholecystectomy with a chronically obstructed bile duct, and one patient presented after cholecystectomy from intraoperative bile duct injury. After access to the biliary system was obtained, a cholangiogram was obtained. After the desired duct was isolated, it was copiously irrigated with saline solution. A glue solution containing NBCA glue, Ethiodol, and tantalum powder was delivered into the duct through a polyethylene catheter that had been irrigated with dextrose solution. RESULTS: Four patients had problems arising from isolated segmental ductal systems that had no communication with the normal biliary ductal system and were treated successfully on the first attempt. In two patients, there was communication to the main biliary ductal system and a persistent bile leak occurred that required placement of a coil and a second final gluing procedure. The only complication observed was unintentional spillage of glue into the main biliary system in one patient, which was ultimately clinically insignificant. CONCLUSIONS: The use of NBCA glue in obliteration of bile ducts is a safe procedure with excellent results in patients with complications from isolated segmental ducts. Although a repeat procedure may be necessary if the duct communicates with the main biliary tree, the procedure can decrease the morbidity associated with chronic external biliary drainage.

Characterization and aging study of currency ink and currency canine training aids using headspace SPME/GC-MS.

Solid-phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS) was used to characterize the volatile components associated with U.S. currency, U.S. currency inks, and Canadian currency. Compounds that can be attributed to the ink-curing process include series of straight-chain aldehydes, alkenals, acids, alcohols, and ketones and a series of lactones and 2-alkyl furans. Solvent compounds include naphthenic and paraffinic hydrocarbons with a profile typical of petroleum products, alkyl cyclohexanes, various ethylene glycol alkyl ethers, and traces of chlorinated solvents. Trace levels of 2-phenoxyethanol, a solvent often used in ink formulations, were also detected. Environmental contaminants, those compounds found in circulating currency but not in currency ink, include 2,2'-diethyl-1,1'-biphenyl, methyl benzoate and salicylate, menthol, limonene, dimethyl and diethyl phthalate, and ionol. Not including simple hydrocarbons, over 100 compounds were identified in the headspace of currency-related samples.