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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Comparison of Inversion (“flipping”) Rates Among Different Port Designs: A Single-Center Experience

PurposeTo compare incidence of port inversion among different types of implantable venous access devices.Materials and Methods Records of patients who underwent imaging-guided subcutaneous port placement without port fixation between July 2001 and April 2015 were reviewed with use of a quality assurance database. 1930 patients with complete follow-up (death or explant) were included in the study. Collected data included date and indication for port placement, port type, venous access site, immediate and long-term complications, indication for removal, and total number of catheter days. BMI of patients with inverted ports was also calculated.Results Port inversion within the pocket was observed in 18 patients (0.9%) including 7/82 (9%) of Dignity ports, 4/126 (3%) of Vaxcel plastic arm ports, 3/142 (2%) of Smartports, 2/100 (2%) of Powerports, 1/14 (7%) of Vaccess ports, and 1/1421 (0.07%) of Vortex LP ports. Among these designs, the inversion rate was significantly lower in Vortex LP ports (0.1%) (P < 0.05). There was a trend toward higher inversion rate of Dignity ports, which have a rectangular design with a relatively narrow base. Mean dwell in inverted ports was 114 days (7–580).Conclusion The incidence of port inversion without suture fixation of the port base to the pocket is extremely low. The present study shows differences in inversion incidence based on port design.Level of Evidence: Case Series, Level IV.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Ischemic Gastric Conditioning by Preoperative Arterial Embolization Before Oncologic Esophagectomy: A Single-Center Experience

PurposeSurgical esophagectomy is the gold standard treatment of early-stage esophageal cancer. The procedure is complicated with significant morbidity; the most severe complication being the anastomotic leakage. Anastomotic fistulas are reported in 5–25% of cases and are mainly due to gastric transplant ischemia. Here, we report our experience of ischemic pre-conditioning using preoperative arterial embolization (PreopAE) before esophagectomy.Materials and MethodsThe medical records of all patients who underwent oncologic esophagectomy from 2008 to 2015 were retrospectively reviewed. Patients were divided into two groups: patients who received PreopAE, and a control group of patients who did not benefit from ischemic pre-conditioning. The target arteries selected for PreopAE were the splenic artery, left gastric artery, and right gastric artery. Evaluation of the results was based on anastomotic leakage, postoperative mortality, technical success of PreopAE, and complications related to the embolization procedure.ResultsForty-six patients underwent oncologic esophagectomy with PreopAE and 13 patients did not receive ischemic conditioning before surgery. Thirty-eight PreopAE were successfully performed (83%), but right gastric artery embolization failed for 8 patients. Anastomotic leakage occurred in 6 PreopAE patients (13%) and in 6 patients (46%) in the control group (p = 0.02). The mortality rate was 2% in the PreopAE group and 23% in the control group (p = 0.03). Eighteen patients suffered from partial splenic infarction after PreopAE, all treated conservatively.ConclusionPreoperative ischemic conditioning by arterial embolization before oncologic esophagectomy seems to be effective in preventing anastomotic leakage.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Median Arcuate Ligament Syndrome: A Single-Center Experience with 23 Patients

BackgroundMedian arcuate ligament syndrome (MALS) is a rare entity that occurs when the median arcuate ligament of the diaphragm is low-lying, causing a compression to the underlying celiac trunk. We reviewed the vascular changes associated with MALS in an effort to emphasize the seriousness of this disease and the complications that may result.MethodsThis is a retrospective descriptive analysis of 23 consecutive patients diagnosed with MALS between January 1, 2012 and December 31, 2015 at a tertiary medical center. Computed tomographic (CT) scans, medical records, and patient follow-up were reviewed.ResultsThe number of patients included herein was 23. The median age was 56 years (17–83). Sixteen patients (69.6%) had a significant arterial collateral circulation. Eleven patients (47.8%) were found to have visceral artery aneurysms; 4 patients (36.4%) bled secondary to aneurysm rupture. All ruptured aneurysms were treated with endovascular approach. The severity of the hemodynamic changes appears to be greater with complete occlusion,ConclusionsMALS causes pathological hemodynamic changes within the abdominal vasculature. Follow-up is advised for patients who develop a collateral circulation. Resulting aneurysms should preferably be treated when the size ratio approaches three. Treatment of these aneurysms can be done via an endovascular approach coupled with possible celiac artery decompression to restore physiologic blood flow.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

Recurrence of Lower Urinary Tract Symptoms Following Prostate Artery Embolization for Benign Hyperplasia: Single Center Experience Comparing Two Techniques

PurposeTo compare recurrence of lower urinary tract symptoms (LUTS) recurrence at 12 months following original prostate artery embolization (oPAE) or “proximal embolization first, then embolize distal” (PErFecTED) PAE for benign prostatic hyperplasia (BPH).Materials and Methods105 consecutive patients older than 45 years, with prostate size greater than 30 cm{sup 3}, International Prostate Symptom Score (IPSS) ≥ 8, quality of life (QoL) index ≥ 3, and refractory status or intolerance of medical management were prospectively enrolled between June 2008 and August 2013. The study was IRB-approved, and all patients provided informed consent. Patients underwent oPAE or PErFecTED PAE and were followed for at least 12 months. Technical success was defined as bilateral embolization and clinical success (non-recurrence) was defined as removal of the Foley catheter in patients with urinary retention, IPSS < 8 and QoL index < 3 at 12 months of follow-up. Nonparametric statistics were used to compare the study groups due to the size of the study population and distributions of clinical data.Results97 patients had 12-month data and were categorized as oPAE without recurrence (n = 46), oPAE with recurrence (n = 13), PErFecTED without recurrence (n = 36), or PErFecTED with recurrence (n = 2). Recurrence was significantly more common in oPAE patients (χ{sup 2}, p = 0.026). Unilateral embolization was significantly associated with recurrence among patients who underwent oPAE (χ{sup 2}, p = 0.032).ConclusionsBoth oPAE and PErFecTED PAE are safe and effective methods for treatment of LUTS, but PErFecTED PAE is associated with a significantly lower rate of symptom recurrence.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

A Single-Institution Experience in Percutaneous Image-Guided Biopsy of Malignant Pleural Mesothelioma

PurposeMesothelioma has been considered a difficult pathologic diagnosis to achieve via image-guided core needle biopsy. The purpose of this study was to assess the diagnostic sensitivity of percutaneous image-guided biopsy for diagnosis of pleural mesothelioma.Materials and MethodsRetrospective review was performed to identify patients with a confirmed diagnosis of pleural mesothelioma and who underwent image-guided needle biopsy between January 1, 2002, and January 1, 2016. Thirty-two patients with pleural mesothelioma were identified and included for analysis in 33 image-guided biopsy procedures. Patient, procedural, and pathologic characteristics were recorded. Complications were characterized via standardized nomenclature [Common Terminology for Clinically Adverse Events (CTCAE)].ResultsPercutaneous image-guided biopsy was associated with an overall sensitivity of 81%. No CTCAE clinically significant complications were observed. No image-guided procedures were complicated by pneumothorax or necessitated chest tube placement. No patients had tumor seeding of the biopsy tract.ConclusionPercutaneous image-guided biopsy can achieve high sensitivity for pathologic diagnosis of pleural mesothelioma with a low procedural complication rate, potentially obviating need for surgical biopsy.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Custom-Made Endograft for Endovascular Repair of Thoraco-Abdominal Aneurysm and Type B Dissection: Single-Centre Experience

AimsTo report a series of patients treated with the Jotec custom-made endograft for thoraco-abdominal aneurysms and dissections and identify predictive factors for re-intervention.MethodsWe retrospectively analysed 49 patients unsuitable for surgery, treated between 2011 and 2017 (71.3 ± 9.5 years; 15 females). Indications included Crawford type 4 aneurysm in 25 patients, type 3 in 13, type 2 in 4, type 1 in 2 and chronic aneurysmal dilatation of the false lumen following dissection in 5 cases. Mean aneurysm diameter was 58.7 ± 8.4 mm. The study aims were to assess procedural success, complications rate, mortality and long-term follow-up. We also analysed factors that predicted the need for re-intervention.ResultsThe endograft was successfully deployed in all patients, catheterization of the fenestration and/or branches was achieved in 152/156 (97.4%) vessels. Early complications occurred in 10 patients (3 paraplegia, 3 haemorrhages, pancreatitis, aortic rupture, iliac artery rupture, 2 strokes). Thirty-day mortality was 10.2% and 180-day mortality 14.3%; two non procedure related deaths occurred. Mean follow-up was 23.6 ± 29.9 months [range 1–80]. No patients needed surgical explantation or developed significant renal impairment. Endoleak rate was 34.6% and re-intervention rate 9.7%. The aneurysm sac reduced or was stable in 36/49, and enlarged in 9/49 patients prompting re-intervention. Primary, primary-assisted and secondary patency of fenestrations/branches at 80 months was 90, 96 and 100%. Re-intervention was required more frequently in braches than in fenestrations, most commonly the external type branches.ConclusionsThe results of the Jotec endograft are comparable to other devices, with acceptable complication and re-intervention rates. Fenestration and inner-branch should be preferred due to lower re-intervention rates.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Radiofrequency Wire Recanalization of Chronically Occluded Venous Stents: A Retrospective, Single-Center Experience in 15 Patients

Introduction: Chronically occluded venous stents may be difficult to salvage, necessitating multiple approaches and adjunctive techniques. Radiofrequency wires have been used to cross chronic obstructions in a variety of settings. Herein, radiofrequency wire recanalization (RFWR) of chronically occluded venous stents is presented. Materials and Methods: Fifteen patients (8 males; 7 females) aged 23–74 years (median 42 years) underwent prior venous stenting in the setting of venous occlusions. Seven had an underlying coagulopathy, three had May–Thurner syndrome, three had provoked deep venous thrombosis, one had a dialysis fistula, and one had pacer leads in situ. All indwelling venous stents were chronically occluded and symptomatic. Out of 15 patients, 13 (87%) had iliocaval venous stents, while two (13%) had superior vena cava and/or upper extremity venous stents. After failing conventional and blunt recanalization techniques, RFWR was performed to traverse the chronic occlusions. Technical success and complications were recorded. Results: Fifteen patients underwent 19 procedures. Twelve patients underwent one procedure, two patients had two procedures, and one patient had three procedures. RFWR alone was used in 12/19 (63%) procedures, while 7/19 (37%) required adjunctive sharp recanalization techniques. Technical success or crossing of the occlusion with flow restoration through the occluded segments was achieved in 17/19 (89%). One major and one minor complication occurred. Conclusion: Radiofrequency wire recanalization is an effective adjunct to revise chronically occluded venous stents, potentially increasing procedural success in challenging cases.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

A New Fully Covered Irradiation Stent Versus a Partially Covered Irradiation Stent for Unresectable Malignant Dysphagia: A Single-Center Experience

Purpose: To assess the efficacy and safety of a newly developed fully covered irradiation stent (FCIS) compared with a partially covered irradiation stent (PCIS) in patients with unresectable malignant dysphagia. Materials and Methods: Data of 195 patients [158 (81.0%) males, median age of 75 years (range 49–89 years)] who underwent FCIS or PCIS placement for unresectable malignant dysphagia from January 2012 to November 2017 were retrospectively analyzed. The median follow-up time was 181 days (range 4–547 days). Outcomes were measured in terms of recurrent dysphagia (primary), technical success, clinical success, overall survival, and adverse events. Recurrent dysphagia was analyzed by Fine–Gray regression model. Results: The technical success rate was 97.8% (87/89) in the FCIS group and 99.1% (105/106) in the PCIS group (P = 0.59). The clinical success rate was 100.0% in both groups. There was no statistically significant difference in the recurrent dysphagia rate between the FCIS and PCIS groups (21.8% vs. 28.6%; P = 0.12). Compared with PCISs, FCISs were associated with a decrease in tissue/tumor growth rate (11.5% vs. 21.9%; P = 0.01), while stent migration rates were statistically comparable (11.5% vs. 5.7%; P = 0.23). The median overall survivals were comparable between the FCIS and PCIS groups (164 days vs. 162 days; P = 0.70). A dysphagia score of 4 and metastasis were risk factors for survival. No significant differences were observed in the rates of adverse events, including chest pain, fistula formation, hemorrhage, and aspiration pneumonia (P > 0.05). Conclusion: For patients with unresectable malignant dysphagia, this newly developed FCIS can provide efficacy and safety comparable to those of a PCIS. Compared with PCIS, this FCIS is more successful in preventing tissue/tumor growth, with a comparable stent migration rate.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2018

Single-Center Experience Implementing the LOINC-RSNA Radiology Playbook for Adult Abdomen/Pelvis CT and MR Procedures Using a Semi-Automated Method

The LOINC-RSNA Radiology Playbook represents the future direction of standardization for radiology procedure names. We developed a software solution (“RadMatch”) utilizing Python 2.7 and FuzzyWuzzy, an open-source fuzzy string matching algorithm created by SeatGeek, to implement the LOINC-RSNA Radiology Playbook for adult abdomen and pelvis CT and MR procedures performed at our institution. Execution of this semi-automated method resulted in the assignment of appropriate LOINC numbers to 86% of local CT procedures. For local MR procedures, appropriate LOINC numbers were assigned to 75% of these procedures whereas 12.5% of local MR procedures could only be partially mapped. For the standardized local procedures, only 63% of CT and 71% of MR procedures had corresponding RadLex Playbook identifier (RPID) codes in the LOINC-RSNA Radiology Playbook, which limited the utility of RPID codes. RadMatch is a semi-automated open-source software tool that can assist radiology departments seeking to standardize their radiology procedures via implementation of the LOINC-RSNA Radiology Playbook.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2019

Surgical Resection for Metastatic Tumors in the Pancreas: A Single-Center Experience and Systematic Review

Background: Metastatic lesion to the pancreas accounts for approximately 2% of pancreatic neoplasms. There is no prospective, randomized or case-controlled study evaluating the role of pancreatic metastasectomy. Methods: The PubMed, EMBASE, and Cochrane Library electronic databases were searched for studies published between January 1, 2001 and December 31, 2017. Studies with five or more patients who received pancreatic metastasectomy and data from our institution (29 patients) were included. The Kaplan–Meier method was used for survival analysis. Results: A total of 414 patients from 20 institutions who underwent pancreatic resections were included. Of the reported 31 kinds of primary neoplasms, renal-cell carcinoma (RCC) comprised the most (54.3%). At the time of diagnosis, although 40.3% patients were asymptomatic, abdominal pain (34.8%) and jaundice (20.6%) were relatively common. As for surgical type, pancreatoduodenectomy, total pancreatectomy, distal pancreatectomy, and enucleation took up 37.9%, 11.4%, 43.5%, and 7.2% respectively. The mortality and morbidity rates were 1.4% and 48.3% respectively. Patients with symptoms at the time of diagnosis had significantly shorter survival compared with asymptomatic patients (p = 0.017). Those with RCC as primary tumor had significantly longer survival compared with non-RCC patients (p < 0.001). Positive margin also predicts worse prognosis (p = 0.035). Conclusions: Pancreatic metastasectomy is safe and associated with acceptable short- and intermediate-term results. In the conditions of RCC as the primary tumor, being asymptomatic, or negative resection margin, a better prognosis after resection can be achieved.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
NASA NTRS1973

Single photon detection and sub-nanosecond timing resolution with RCA C31034 photomultiplier

The very high quantum efficiencies and low dark count rates achieved with selected RCA C31034 photomultipliers make them attractive candidates for single photoelectron fast timing experiments. Single photoelectron plateau counting and a timing resolution of 0.60 nsec (FWHM) were obtained using fast amplifiers, constant fraction timing discriminators, and a pulsed light emitting diode. A redesign of the C31034 incorporating features of the very fast C31024 is suggested to yield even better timing resolution.

Reisse, R.↗