Sarah B. White

The Small-Caliber Esophagus: Radiographic Sign of Idiopathic Eosinophilic Esophagitis

PURPOSE To evaluate a small-caliber esophagus at barium esophagography with idiopathic eosinophilic esophagitis (IEE) and determine if there is a useful threshold diameter for suggesting this diagnosis. MATERIALS AND METHODS The institutional review board approved this retrospective study and waived informed consent. This study was HIPAA compliant. A search of the radiology database (by using the search term small-caliber esophagus) revealed 10 patients with a small-caliber esophagus at barium esophagography who had IEE (defined as more than 20 eosinophils per high-power field in endoscopic biopsy specimens). Images were reviewed to characterize findings and determine the length of narrowing. Luminal diameters were measured at three levels for nine patients and nine control subjects, and mean diameter, range, and standard deviation were determined at each level. An analysis of variance test was performed to determine whether the difference between the range of mean thoracic esophageal diameters in patients with IEE versus that in control subjects was significant. RESULTS All 10 patients had long-segment but variable-length narrowing of the thoracic esophagus (mean length, 15.4 cm) with tapered margins. The mean diameter at the aortic arch, carina, and one vertebral body above the gastroesophageal junction was 13.9, 14.3, and 15.1 mm, respectively, for patients with small-caliber esophagus versus 20.2, 30.3, and 28.7 mm for control subjects. The mean overall diameter was 14.7 mm for patients with small-caliber esophagus versus 26.3 mm for control subjects. In the nine patients in whom the luminal diameter was measured, the mean thoracic esophageal diameter was 20 mm or less; all nine control subjects had a mean thoracic esophageal diameter greater than 20 mm. The difference in the range of mean thoracic esophageal diameters between these two groups was highly significant (P < .0001), so 20 mm was a useful threshold diameter for suggesting this diagnosis. CONCLUSION The small-caliber esophagus of IEE is characterized at barium esophagography by long-segment but variable-length narrowing of the thoracic esophagus, with a mean length of 15.4 cm, a diameter of 20 mm or less, smooth contours, and tapered margins.

Management of Endoleaks following Endovascular Aneurysm Repair.

Endovascular aneurysm repair (EVAR) has emerged as a viable alternative to open repair for abdominal aortic aneurysms. Endoleaks are a complication unique to EVAR and can occur in up to 25% of patients. In this article, the management of endoleaks following EVAR will be discussed.

90Y Radioembolization of Colorectal Hepatic Metastases Using Glass Microspheres: Safety and Survival Outcomes from a 531-Patient Multicenter Study

Hepatic metastases of colorectal carcinoma are a leading cause of cancer-related mortality. Most colorectal liver metastases become refractory to chemotherapy and biologic agents, at which point the median overall survival declines to 4–5 mo. Radioembolization with 90Y has been used in the salvage setting with favorable outcomes. This study reports the survival and safety outcomes of 531 patients treated with glass-based 90Y microspheres at 8 institutions, making it the largest 90Y study for patients with colorectal liver metastases. Methods: Data were retrospectively compiled from 8 institutions for all 90Y glass microsphere treatments for colorectal liver metastases. Exposure to chemotherapeutic or biologic agents, prior liver therapies, biochemical parameters before and after treatment, radiation dosimetry, and complications were recorded. Uni- and multivariate analyses for predictors of survival were performed. Survival outcomes and clinical or biochemical adverse events were recorded. Results: In total, 531 patients received 90Y radioembolization for colorectal liver metastases. The most common clinical adverse events were fatigue (55%), abdominal pain (34%), and nausea (19%). Grade 3 or 4 hyperbilirubinemia occurred in 13% of patients at any time. The median overall survival from the first 90Y treatment was 10.6 mo (95% confidence interval, 8.8–12.4). Performance status, no more than 25% tumor burden, no extrahepatic metastases, albumin greater than 3 g/dL, and receipt of no more than 2 chemotherapeutic agents independently predicted better survival outcomes. Conclusion: This multiinstitutional review of a large cohort of patients with colorectal liver metastases treated with 90Y radioembolization using glass microspheres has demonstrated promising survival outcomes with low toxicity and low side effects. The outcomes were reproducible and consistent with prior reports of radioembolization.

Long-Term Patency and Clinical Analysis of Expanded Polytetrafluoroethylene-Covered Transjugular Intrahepatic Portosystemic Shunt Stent Grafts.

PURPOSE To evaluate long-term patency and symptomatic recurrence rates following transjugular intrahepatic portosystemic shunt (TIPS) creation with expanded polytetrafluoroethylene (ePTFE)-covered stent grafts and to determine the necessity of extended clinical follow-up beyond 2 years after TIPS creation. MATERIALS AND METHODS A retrospective review including 262 TIPSs created with ePTFE-covered stent grafts between July 2002 and October 2012 was performed. Primary, primary assisted, and secondary patency rates were calculated. Assessment of clinical data included technical, hemodynamic, and clinical success rates, as well as mortality after TIPS creation. RESULTS Primary patency rates at 2, 4, and 6 years were 74%, 62%, and 50%, respectively. Primary assisted patency rates at 2, 4, and 6 years were 93%, 85%, and 78%, respectively. Secondary patency rates at 2, 4, and 6 years were 99%, 91%, and 84%, respectively. Technical and hemodynamic success rates were 99% and 93%, respectively. Clinical success rates for refractory ascites were 66% (complete response) and 90% (partial response); clinical success rate for bleeding/varices was 90%. Mortality rates at 2, 4, and 6 years after TIPS creation were 27%, 38%, and 46%, respectively. At the median wait time until transplantation, patients had an 84% chance of being alive. TIPS dysfunction developed in 21% of patients; 30% of revisions occurred later than 2 years during follow-up. CONCLUSIONS Beyond 2 years after TIPS creation, patency rates gradually decrease, mortality rates continue to increase, and the chance of recurrent ascites or bleeding remains present. Together, these findings suggest that continued clinical follow-up beyond 2 years is necessary in patients with a TIPS created with an ePTFE-covered stent graft.

Neutrophil-to-lymphocyte ratio as a predictor of outcomes for patients with hepatocellular carcinoma: A Western perspective

Neutrophil‐to‐lymphocyte ratio (NLR) is simple, inexpensive, and has been proposed to be predictive in hepatocellular carcinoma (HCC) in Europe and Asia. We aimed to evaluate whether NLR at presentation in a Western center provides any prognostic value compared to other common prognostic scores.

Multimodality Imaging to Assess Immediate Response to Irreversible Electroporation in a Rat Liver Tumor Model

PURPOSE To compare changes on ultrasonographic (US), computed tomographic (CT), and magnetic resonance (MR) images after irreversible electroporation (IRE) ablation of liver and tumor tissues in a rodent hepatoma model. MATERIALS AND METHODS Studies received approval from the institutional animal care and use committee. Forty-eight rats were used, and N1-S1 tumors were implanted in 24. Rats were divided into groups and allocated for studies with each modality. Imaging was performed in normal liver tissues and tumors before and after IRE. MR imaging was performed in one group before and after IRE after hepatic vessel ligation. US images were graded to determine echogenicity changes, CT attenuation was measured (in Hounsfield units), and MR imaging signal-to-noise ratio (SNR) was measured before and after IRE. Student t test was used to compare attenuation and SNR measurements before and after IRE (P < .05 indicated a significant difference). RESULTS IRE ablation produced greater alterations to echogenicity in normal tissues than in tumors. Attenuation in ablated liver tissues was reduced compared with that in control tissues (P < .001), while small attenuation differences between ablated (42.11 HU ± 2.11) and control (45.14 HU ± 2.64) tumors trended toward significance (P = .052). SNR in ablated normal tissues was significantly altered after IRE (T1-weighted images: pre-IRE, 145.95 ± 24.32; post-IRE, 97.80 ± 18.03; P = .004; T2-weighted images, pre-IRE, 47.37 ± 18.31; post-IRE, 90.88 ± 37.15; P = .023). In tumors, SNR differences before and after IRE were not significant. No post-IRE signal changes were observed after hepatic vessel ligation. CONCLUSION IRE induces rapid changes on gray-scale US, unenhanced CT, and MR images. These changes are readily visible and may assist a performing physician to delineate ablation zones from the unablated surrounding parenchyma.

Image-guided biopsy in the era of personalized cancer care: Proceedings from the society of interventional radiology research consensus panel

Alda L. Tam, M.D., Howard J. Lim, M.D., Ignacio I. Wistuba, M.D., Anobel Tamrazi, M.D., Ph.D., Michael D. Kuo, M.D., Etay Ziv, M.D., Ph.D., Stephen Wong, Ph.D., Albert J. Shih, Ph.D., Robert J. Webster III, Ph.D., Gregory S. Fischer, Ph.D., Sunitha Nagrath, Ph.D., Suzanne E. Davis, M.M.S., M.B.A., Sarah B. White, M.D., and Kamran Ahrar, M.D. Departments of Interventional Radiology (A.L.T., K.A.) and Translational Molecular Pathology (I.I.W.); and the Division of Cancer Medicine, Research Planning and Development (S.E.D.); The University of Texas M.D. Anderson Cancer Center, Houston, TX; the Division of Medical Oncology (H.J.L.), University of British Columbia, British Columbia Cancer Agency, Vancouver, British Columbia, Canada; the Division of Vascular and Interventional Radiology (A.T.), Johns Hopkins University School of Medicine, Baltimore, MD; the Department of Radiological Sciences (M.D.K.), David Geffen School of Medicine at UCLA, Los Angeles, CA; the Departments of Interventional Radiology and Computational Biology (E.Z.), Memorial Sloan Kettering Cancer Center, NY, NY; the Houston Methodist Research Institute, Houston, TX and Weill Cornell Medical College of Cornell University, NY, NY (S.W.); the Departments of Mechanical and Biomechanical Engineering (A.J.S.) and the Departments of Chemical and Biomedical Engineering (S.N.), University of Michigan, Ann Arbor, MI; the Department of Mechanical Engineering (R.J.W. 3rd), Vanderbilt University, Nashville, TN; the Automation and Interventional Medicine (AIM) Robotics Lab (G.S.F.) in the Department of Mechanical Engineering, Worcester Polytechnic Institute, Worcester, MA; and, the Division of Vascular and Interventional Radiology (S.B.W.), Medical College of Wisconsin, Milwaukee, WI

Intra-voxel incoherent motion MRI in rodent model of diethylnitrosamine-induced liver fibrosis.

RATIONALE AND OBJECTIVES To compare the apparent diffusion coefficient (ADC) and the perfusion fraction measured by intra-voxel incoherent motion (IVIM) Magnetic Resonance Imaging (MRI) with liver fibrosis degrees in a rodent model. MATERIALS AND METHODS All experiments received approval from our institutional animal care and use committee. Liver fibrosis was induced in 13 rats by oral gavage with diethylnitrosamine; 4 untreated rats with normal livers were used as controls. Diffusion Weighted MRI was performed and 8 gradient factors (0, 50, 100, 150, 200, 300, 400 and 500s/mm(2)) were acquired. The values of ADC, true diffusion coefficient D and perfusion fraction f were measured based on Li Bihans method. The percentage of liver fibrosis was assessed via quantitative analysis of Masson trichrome staining using an average of 30 fields per section. The MRI measurements were compared to the histological fibrotic grade to evaluate the correlation between them. RESULTS ADC contained the contribution of diffusion and perfusion. The ADC and f values decreased significantly with the increasing fibrosis level (correlation coefficient: ADC: ρ=-0.781, p<0.001; f: ρ=-0.720, p=0.001); but D was poorly correlated with fibrosis level (ρ=-0.502, p=0.040). CONCLUSION The hepatic ADC and the perfusion fraction f were significantly correlated with the liver fibrosis level; however, D was not. This might suggest that hepatic perfusion is altered during the progression of hepatic fibrosis.

Assessment and optimization of electroporation-assisted tumoral nanoparticle uptake in a nude mouse model of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a particularly lethal form of cancer. In 2012, the incidence of PDAC was 43,920. Five-year survival for patients with PDAC is around 6%, regardless of staging, making PDAC one of the deadliest forms of cancer. One reason for this dismal prognosis is chemoresistance to the current first-line therapy, gemcitabine. There are multiple factors that contribute to the chemoresistance observed in pancreatic cancer. Among them, desmoplasia has been increasingly seen as a significant contributor to chemoresistance. To overcome desmoplastic chemoresistance, several novel methods of treatment have been developed. Electroporation is one such novel treatment. High electrical fields are applied to cells to create pores that increase cell permeability. It has been previously demonstrated that electroporation enhances the therapeutic efficacy of anticancer drugs in pancreatic tumor models. Nanoparticle-based drug delivery systems constitute a second novel method to overcome desmoplastic chemoresistance. Due to their intrinsic design advantages, nanoparticles have been shown to increase the effectiveness of chemotherapeutic agents, while further reducing or even eliminating side effects. To date, there have been no studies evaluating the cumulative effect of combining both nanoparticle and electroporation strategies to overcome chemoresistance in PDAC. Our preliminary studies assessed the in vitro and in vivo uptake of doxorubicin-loaded iron oxide nanoparticles as a function of electroporation voltage and timing of administration in pancreatic adenocarcinoma cells. Our studies demonstrated that addition of electroporation to administration of nanoparticles significantly increased the amount of intracellular iron oxide nanoparticle uptake by a PANC-1 cell line in an athymic nude mouse model of PDAC. Further, electroporation-assisted nanoparticle uptake could be significantly altered by changing the timing of application of electroporation.

A Single-Center Experience in Capturing Inpatient Evaluation and Management for an IR Practice

PURPOSE To demonstrate that interventional radiologists can capture work relative value units (wRVUs) for the work that is already being performed providing evaluation and management (E&M) clinical services. MATERIALS AND METHODS A team approach was implemented to optimize revenue capture for inpatient E&M. Structured templates were created for inpatient documentation to ensure that maximum wRVUs were captured. Inpatient billing was audited from fiscal year 2011 (1 year before meeting and structured template creation) through fiscal year 2014. Specifically, data were collected on total charges, collections, wRVUs and total number of inpatient E&M encounters, and the level of the billed encounter. RESULTS Retrospective annual audits revealed that overall inpatient E&M billing charges increased by 722%, whereas collections increased by 831% from 2011 to 2014. The wRVUs increased in 2011 from 181.74 to 1,396.9 (669% increase) in 2014, and the number of inpatient E&M encounters billed increased from 130 to 693 (433% increase) over that same time period. Lower level billing (level I) declined from 30% to 19%, and complex billing levels (level II or higher) increased from 70% to 81%. CONCLUSIONS By implementing a systems approach to revenue management, which includes physician and billing staff meetings and the use of structured templates, billing capture from inpatient E&M services can be improved.