Update on Percutaneous Ablation for Sarcoma.

PURPOSE OF REVIEW: To provide an update on the current state of percutaneous thermal ablation in the treatment of sarcoma. RECENT FINDINGS: Data continue to accrue in support of ablation for local control and palliation of specific sarcoma subtypes such as extra-abdominal desmoid fibromatosis and for broader indications such as the treatment of oligometastatic disease. The synergistic possibilities of various combination therapies such as cryoablation and immunotherapy represent intriguing areas of active investigation. Histotripsy is an emerging non-invasive, non-thermal ablative modality that may further expand the therapeutic arsenal for sarcoma treatment. Percutaneous thermal ablation is a valuable tool in the multidisciplinary management of sarcoma, offering a minimally invasive adjunct to surgery and radiation therapy. Although there remains a paucity of high-level evidence specific to sarcomas, ablation techniques are demonstrably safe and effective for achieving local tumor control and providing pain relief in select patients and are of particular benefit in those with metastatic disease or requiring palliative care.

Normal and Abnormal Appearances of the Ovaries during Assisted Reproduction: Multimodality Imaging Review.

Infertility is a common diagnosis that prompts many couples and individuals to seek assisted reproductive technology (ART) for assistance with conception. These technologies have become increasingly used in the United States in the past several decades, with 326 468 ART cycles performed in 2020, resulting in 75 023 live births. This ubiquity of ART also increases the likelihood that radiologists will encounter both normal and abnormal imaging findings associated with these treatments. Thus, radiologists of all subspecialties should be familiar with the multimodality appearance of the ovaries and pelvis in patients undergoing ART treatments. Furthermore, it is imperative that radiologists understand the appearance expected during different stages of the ART process. During stimulated ovulatory cycles, it is normal and expected for the ovaries to appear enlarged and to contain numerous cystic follicles, often with a small to moderate volume of pelvic free fluid. After oocyte retrieval, hemorrhagic ovarian follicles and a small to moderate volume of blood products in the cul-de-sac can be expected to be seen. Multiple nonemergency and emergency complications are related to ART, many of which can be seen at imaging. The most encountered emergency complications of ART include ovarian hyperstimulation syndrome, ectopic pregnancy, heterotopic pregnancy, multiple gestations, ovarian torsion, and procedural complications related to oocyte retrieval. These complications have important clinical implications, thus necessitating accurate and timely detection by the radiologist and the clinical team. ©RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

A Single-Institution Experience in Percutaneous Image-Guided Cryoablation of Lymph Node Metastases.

OBJECTIVE. The purpose of this study was to assess the feasibility, safety, and efficacy of percutaneous cryoablation for the treatment of lymph node metastases. MATERIALS AND METHODS. In this single-institution retrospective study 55 patients were identified who underwent CT-guided cryoablation of metastatic lymph nodes between November 2006 and September 2019. Patient demographics, disease characteristics, and procedural details were recorded. The primary endpoints were technical success and major complications. The secondary endpoints were time to local and time to distant progression. Complications were graded according to the Society of Interventional Radiology consensus guidelines. RESULTS. The study sample comprised 55 patients (42 men, 13 women; mean age 64 ± 12 years) who underwent 61 cryoablation procedures to treat 65 lymph node metastases. Targeted nodes measured 1.7 ± 1.2 cm in mean short-axis diameter. Technical success was achieved in 60 of 61 cryoablation procedures (98%). Adjunctive maneuvers performed to protect adjacent structures included hydrodissection (n = 40), ureteral stenting (n = 3), and neural monitoring (n = 3). There were two Society of Interventional Radiology major complications (3%): pneumothorax (n = 1) and bleeding (n = 1). Local tumor control was achieved in treatment of 53 of 65 (82%) nodal metastases within a median of 25 months (range, 1-121 months) of follow-up. Local progression occurred in 12 of 65 cases (18%); the median time to recurrence was 11 months. CONCLUSION. Percutaneous cryoablation of nodal metastases is feasible and safe. Further investigation is warranted to assess the long-term efficacy of this technique and to define its role in oncologic care.

Challenges in Diagnosis and Management of Hemobilia.

Hemobilia, or hemorrhage within the biliary system, is an uncommon form of upper gastrointestinal (GI) bleeding that presents unique diagnostic and therapeutic challenges. Most cases are the result of iatrogenic trauma, although accidental trauma and a variety of inflammatory, infectious, and neoplastic processes have also been implicated. Timely diagnosis can often be difficult, as the classic triad of upper GI hemorrhage, biliary colic, and jaundice is present in a minority of cases, and there may be considerable delay in the onset of bleeding after the initial injury. Therefore, the radiologist must maintain a high index of suspicion for this condition and be attuned to its imaging characteristics across a variety of modalities. CT is the first-line diagnostic modality in evaluation of hemobilia, while catheter angiography and endoscopy play vital and complementary roles in both diagnosis and treatment. The authors review the clinical manifestations and multimodality imaging features of hemobilia, describe the wide variety of underlying causes, and highlight key management considerations.©RSNA, 2021.

Imaging pediatric acute appendicitis during the coronavirus disease 2019 (COVID-19) pandemic: collateral damage is variable.

BACKGROUND: Since coronavirus disease 2019 (COVID-19) was declared a worldwide pandemic in March 2020, many authors have noted the collateral damage on non-COVID-19-related illnesses. These indirect effects of the pandemic have resulted in people presenting later and with more severe stages of disease, even if their diagnoses are not directly related to SARS-CoV-2, the virus that causes COVID-19. OBJECTIVE: We studied these indirect effects of COVID-19 on the imaging workup and outcomes for pediatric patients at our center who had acute appendicitis during the pandemic. MATERIALS AND METHODS: We performed a retrospective review of cases in children ≤18 years who were evaluated for acute appendicitis during the same period, March 1 to May 31, in both 2019 and 2020. We compared demographic and clinical data as well as surgical and pathological findings, and we graded imaging findings according to severity. Differences in patient outcomes were assessed using the Wilcoxon rank sum test and the Pearson chi-square test. RESULTS: The total number of pediatric patients evaluated with imaging for acute appendicitis dropped by 43% between 2019 and 2020 (298 vs. 169), but the total number of children treated remained similar (59 vs. 51). There was proportionate use of US and CT in each timeframe but a higher percentage of positive imaging findings in 2020 (50/169, 29.6% vs. 56/298, 18.7% in 2019, P=0.04). There were more imaging examinations with features of complicated appendicitis among positive cases (9/51, 18% vs. 5/59, 8% in 2019, P=0.08) and more pathologically proven perforated cases during the pandemic (14/51, 27% vs. 6/59, 10% in 2019, P=0.11), although these results did not reach statistical significance. There were no changes in surgical management, vital signs, laboratory values, length of stay or complication rates. CONCLUSION: There was a large drop in the number of pediatric patients imaged for acute appendicitis during the acute phase of the COVID-19 pandemic despite similar numbers of patients treated. The utilization trends of US vs. CT remained stable between time periods. The differences in imaging findings and perforation rates were less pronounced compared to other published studies.

Diagnostic Yield of Rescreening Adults for Pulmonary Arteriovenous Malformations.

PURPOSE: To determine the yield of rescreening adult hereditary hemorrhagic telangiectasia (HHT) patients with initial negative screening CT for pulmonary arteriovenous malformations (PAVMs). MATERIALS AND METHODS: Patients with a definite diagnosis of HHT were identified in the University of Toronto, Université de Montréal, and Mayo Clinic HHT databases. Inclusion criteria were: (i) definite diagnosis of HHT; (ii) initial negative PAVM screening based on bubble echocardiography and/or chest CT; and (iii) minimum 2-year imaging follow-up. A positive rescreen was defined as a newly detected PAVM on follow-up CT. Frequency of new PAVMs was calculated at 3 ± 1 years, 5 ± 1 years, 7-9 years, and ≥10 years. The primary endpoint was the rate of new PAVMs at 5 ± 1 years. RESULTS: One hundred seventy-two patients (mean age, 49.6 ± 16.7 years; 59% female) were followed for a median of 7 years. Nine patients (5.2%) had newly detected PAVMs. At the 3-, 5-, 7-, and ≥10-year time points, the cumulative rate of newly detected PAVMs was 1.8% (3/166), 5.0% (7/140), 8.8% (8/91), and 13.8% (9/65), respectively. Median feeding artery diameter was 1.3 mm. One patient had a feeding artery larger than 3 mm discovered after 6 years and was treated with embolization. The overall rate of newly detected PAVMs was 0.7%/patient-year. CONCLUSIONS: There is a definite but low rate of newly detected PAVMs in HHT patients with initial negative screening studies. No new treatable PAVMs were identified at the 5-year mark, although 1 treatable case was identified after 6 years. These findings suggest that a longer screening interval may be warranted.

Comparison of Bleeding Complications between Transplenic versus Transhepatic Access of the Portal Venous System.

PURPOSE: To evaluate the incidence of bleeding complications between transplenic (TS) and transhepatic (TH) access in portal venous interventions. MATERIALS AND METHODS: Retrospective review of patients who underwent TS or TH access for portal venous system interventions from January 2000 to August 2017. Only procedures with clinical and laboratory follow-up were included (n = 148). Twenty-four TS procedures were performed in 22 patients, and 124 TH procedures were performed in 114 patients. The main indications were for angioplasty/stent, embolization of varices/shunt, or portal vein embolization, with no difference between the groups. Mean patient age and sex were not significantly different between the groups (P values .445 and .682, respectively). Mean follow up was 2.3 years (range 0.1-14.2). There was no significant difference between the international normalized ratio (P = .300) and platelets (P = .234) before the procedure between the 2 cohorts. RESULTS: Technical success of vascular access and procedural success was achieved in 22/24 (91.6%) TS procedures and 120/124 (96.8%) TH procedures (P = .238). There was no significant difference in bleeding complications between the 2 groups (3/24 [12.5%] TS vs 10/124 [8.1%] TH; P = .44). There was no significant difference in major bleeding complications (SIR classification ≥ C; 1/24 [4.2%] TS vs 4/124 [3.2%] TH; P = .789).There was no significant difference in the hemoglobin before or after the procedure (g/dL), with average change -1.1 g/dL (range -3.4 to +1.0) in the TS group and 1.0 g/dL (range -4.5 to +1.9) in the TH group (P = .540). Finally, there was no significant difference in proportion of patients requiring blood transfusion after the procedure (P = .520), with 2 (8.3%) in the TS group requiring an average of 4 units (range 2-6) and 17 (13.7%) in the TH group requiring an average of 3.5 units (range 1-26). CONCLUSIONS: These data suggest no significant difference in bleeding complications between TS and TH access for portal venous interventions.

11C-Choline PET/CT for Detection and Localization of Parathyroid Adenomas.

OBJECTIVE: The purpose of this study is to determine the efficacy of 11C-choline PET/CT for the detection of parathyroid adenomas by retrospectively reviewing a large patient population. MATERIALS AND METHODS: In this single-institution retrospective study, 7088 11C-choline PET/CT scans performed of 2933 men with prostate cancer from January 2005 through February 2016 were evaluated. Patients with suspected parathyroid adenomas were identified through a review of the electronic medical record and relevant imaging. Patient demographics, laboratory results, and lesion characteristics were noted. Pathologically proven parathyroid adenomas and lesions in patients with imaging or laboratory findings consistent with the diagnosis were considered positive. RESULTS: Thirteen men (mean [± SD] age, 72 ± 7 years) with pathologically or laboratory-proven parathyroid adenomas were identified. All had abnormally elevated serum calcium and parathyroid hormone levels. All adenomas were tracer avid on 11C-choline PET/CT (maximum standardized uptake value, 5.6 ± 3.0), with activity averaging 4.2 times that of the blood pool and 2.1 times that of the adjacent thyroid. One case of an ectopic adenoma was identified. Of the six pathologically confirmed cases, none displayed high-grade features such as capsular, vascular, or adjacent tissue invasion. Three additional patients with possible parathyroid adenomas at 11C-choline PET/CT were ultimately found to have thyroid lesions on the basis of tissue diagnosis; however, none of these patients had abnormal calcium or parathyroid hormone levels. CONCLUSION: In our patient population, 11C-choline PET/CT identified parathyroid adenomas with high specificity. Prospective investigation is warranted to validate this result and delineate the utility of 11C-choline PET/CT relative to other modalities.

Correlation of Doxorubicin Delivery and Tumor Necrosis after Drug-eluting Bead Transarterial Chemoembolization of Rabbit VX2 Liver Tumors.

Purpose To quantify the correlation between doxorubicin (DOX) delivery and tumor necrosis after drug-eluting bead (DEB) transarterial chemoembolization (TACE). Materials and Methods In this animal care committee-approved study, New Zealand white rabbit VX2 liver tumors were treated transarterially with DOX-loaded 70-150-µm DEBs in five treatment groups with varying drug doses: sham (saline), 0 mg, 12.5 mg, 25 mg, and 37.5 mg. DEB TACE was followed by 3- and 7-day sacrifice, tumor harvest, and sectioning. Drug delivery was assessed by using fluorescence imaging, and tumor necrosis was quantified by means of histologic analysis. Statistical correlation of DOX delivery and tumor necrosis was performed by using the Spearman rank correlation coefficient (ρ). Results Thirty-six VX2 tumors (median diameter, 1.3 cm) in 20 rabbits (median weight, 2.8 kg) underwent successful DEB TACE. Treatment groups included eight, seven, eight, five, and eight tumors of similar size (P > .05). Tumors showed progressively greater DOX extent (sham, 0%; 0 mg, 0%; 12.5 mg, 3%; 25 mg, 20%; and 37.5 mg, 27%) and intensity (sham, 0.4; 0 mg, 1.9; 12.5 mg, 8.5; 25 mg, 9.6; and 37.5 mg, 18.3) and higher median percentage necrosis (sham, 68%; 0 mg, 64%; 12.5 mg, 76%; 25 mg, 78%; and 37.5 mg, 83%) across DOX treatment groups. Correlation of DOX extent (ρ = 0.975, P = .005) and intensity (ρ = 0.900, P = .037) with percentage tumor necrosis was statistically significant. Conclusion Incremental increases in DOX correlate with greater necrosis in rabbit VX2 liver tumors after DEB TACE. This result indicates an essential role for chemotherapy-induced cytotoxicity in TACE effectiveness and supports the use of chemotherapeutic drugs in transarterial therapy. (©) RSNA, 2016 Online supplemental material is available for this article.

Gene expression in hepatocellular carcinoma: pilot study of potential transarterial chemoembolization response biomarkers.

PURPOSE: To perform a feasibility study to explore the relationship between hepatocellular carcinoma genetics and transarterial chemoembolization treatment response to identify potential biomarkers associated with enhanced treatment efficacy. MATERIALS AND METHODS: In this single-institution study, pretreatment hepatocellular carcinoma biopsy specimens for tumors in 19 patients (14 men, five women; mean age, 59 y) treated with chemoembolization between 2007 and 2013 were analyzed for a panel of 60 chemotherapy-sensitivity, hypoxia, mitosis, and inflammatory genes with the QuantiGene Plex 2.0 mRNA detection assay. Demographic, disease, and procedure data and tumor response outcomes were collected. Quantitative mRNA levels were compared based on radiologic response between tumors exhibiting complete response (CR) versus partial response (PR). RESULTS: The study sample included 19 biopsy specimens from tumors (mean size, 3.0 cm; grade 1, n = 6; grade 2, n = 9; grade 3, n = 4) in patients treated with a mean of two conventional chemoembolization sessions. Thirteen and six tumors exhibited CR and PR, respectively, at a mean of 116 days after treatment. Tumors with CR showed a significant increase in (P < .05) or trend toward (P < .1) greater (range, 1.49-3.50 fold) pretreatment chemotherapy-sensitivity and mitosis (ATF4, BAX, CCNE1, KIF11, NFX1, PPP3CA, SNX1, TOP2A, and TOP2B) gene mRNA expression compared with tumors with PR, in addition to lower CXCL10 levels (0.48-fold), and had significantly (P < .05) higher (1.65-fold) baseline VEGFA levels. CONCLUSIONS: Genetic signatures may allow prechemoembolization stratification of tumor response probability, and gene analysis may therefore offer an opportunity to personalize locoregional therapy by enhancing treatment modality allocation. Further corroboration of identified markers and exploration of their respective predictive capacity thresholds is necessary.

Should transjugular intrahepatic portosystemic shunt stent grafts be underdilated?

Although underdilation of transjugular intrahepatic portosystemic shunt (TIPS) stent grafts is commonly performed to limit complications arising from excessive portosystemic shunting, it is uncertain whether underdilated stents retain their smaller diameter indefinitely or eventually expand to nominal caliber. In this investigation, postprocedure computed tomography (CT) was used to compare diameters of underdilated TIPSs and TIPSs expanded to a nominal diameter of 10 mm in 61 cases. The groups had comparable shunt diameters on post-TIPS imaging (9.8 mm vs 9.9 mm; P = .079), with similar incidences of hepatic encephalopathy (34% vs 20%; P = .372), indicating stent self-expansion over time, and bringing into question the advantages of underdilation for customization of shunt caliber.

Clearing the Confusion over Hepatic Encephalopathy After TIPS Creation: Incidence, Prognostic Factors, and Clinical Outcomes.

PURPOSE: To assess the incidence, prognostic factors, and clinical outcomes of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) creation. MATERIALS AND METHODS: In this single-institution retrospective study, 191 patients (m:f = 114:77, median age 54 years, median Model for End-Stage Liver Disease or MELD score 14) who underwent TIPS creation between 1999 and 2013 were studied. Medical record review was used to identify demographic characteristics, liver disease, procedure, and outcome data. Post-TIPS HE within 30 days was defined by new mental status changes and was graded according to the West Haven classification system. The influence of data parameters on HE occurrence and 90-day mortality was assessed using binary logistic regression. RESULTS: TIPS was successfully created with hemodynamic success in 99 % of cases. Median final PSG was 7 mmHg. HE incidence within 30 days was 42 % (81/191; 22 % de novo, 12 % stable, and 8 % worsening). Degrees of HE included grade 1 (46 %), grade 2 (29 %), grade 3 (18 %), and grade 4 (7 %). Medical therapy typically addressed HE, and shunt reduction was necessary in only three cases. MELD score (P = 0.020) and age (P = 0.009) were significantly associated with HE development on multivariate analysis. Occurrence of de novo HE post-TIPS did not associate with 90-day mortality (P = 0.400), in contrast to worsening HE (P < 0.001). CONCLUSIONS: The incidence of post-TIPS HE is non-trivial, but symptoms are typically mild and medically managed. HE rates are higher in older patients and those with worse liver function and should be contemplated when counseling on expected TIPS outcomes and post-procedure course.

MELD score for prediction of survival after emergent TIPS for acute variceal hemorrhage: derivation and validation in a 101-patient cohort.

UNLABELLED: BACKGROUND AND RATIONALE FOR THE STUDY: The Model for End Stage Liver Disease (MELD) score has not been derived and validated for the emergent transjugular intrahepatic portosystemic shunt (TIPS) population. We sought to identify predictive factors for survival among emergent TIPS patients, and to substantiate MELD for outcomes prognostication in this population. RESULTS: 101 patients with acute life threatening variceal hemorrhage underwent emergent TIPS (defined by failed endoscopic therapy for active bleeding, acute hemoglobin drop, ≥ 2-unit transfusion requirement, and/or vasopressor need) at between 1998-2013. Demographic, clinical, laboratory, and procedure parameters were analyzed for correlation with mortality using Cox proportional hazards regression to derive the prognostic value of MELD constituents. Area under receiver operator characteristic (AUROC) curves was used to assess the capability of MELD prediction of mortality. TIPS were created 119 ± 167 h after initial bleeding events. Hemodynamic success was achieved in 90%. Median final portosystemic pressure gradient was 8 mmHg. Variceal rebleeding incidence was 21%. The four original MELD components showed significant correlation with mortality on multivariate Cox regression: baseline bilirubin (regression coefficient 0.366), creatinine (0.621), international normalized ratio (1.111), and liver disease etiology (0.808), validating the MELD system for emergent cases. No other significant predictive parameters were identified. MELD was an excellent predictor of 90-day mortality in the emergent TIPS population (AUROC = 0.842, 95% CI 0.755-0.928). CONCLUSIONS: Based on independent derivation of prognostic constituents and confirmation of predictive accuracy, MELD is a valid and reliable metric for risk stratification and survival projection after emergent TIPS.

Characteristics of primary and secondary hepatic malignancies associated with hepatopulmonary shunting.

PURPOSE: To identify liver tumor characteristics associated with low (<10%), intermediate (10%-20%), and high (>20%) lung shunt fraction (LSF) at technetium 99m ((99m)Tc) macroaggregated albumin (MAA) imaging performed before yttrium 90 ((90)Y) radioembolization (RE). MATERIALS AND METHODS: In this single-center retrospective study, 141 patients (70 with hepatocellular carcinoma [HCC], 71 with other tumors; 95 men, 45 women; median age, 61 years) underwent mapping arteriography with (99m)Tc-MAA LSF calculation before (90)Y RE from 2006 to 2012. Tumor characteristics, including tumor type, index lesion size and morphologic structure (circumscribed, infiltrative), focality (solitary oligonodular, multinodular), disease distribution (unilobar, bilobar), tumor burden (≤50%, 50%), portal vein invasion (present, absent), and arterioportal shunting (present, absent) were correlated with (99m)Tc-MAA imaging-calculated LSFs at univariate and multivariate analysis. RESULTS: Median LSF was 8.4% (HCC, 9.0%; other tumors, 8.3%). LSF greater than 20% occurred in 14% of HCCs, but only in 3% of other tumors (P = .004). For HCC, tumor morphologic structure (P = .022), tumor burden (P < .001), main portal vein invasion (P = .033), and arterioportal shunting (P < .001) were significantly associated with different LSF categories at univariate analysis; infiltrative morphologic structure, tumor burden greater than 50%, portal vein invasion, and shunting had confirmed association with high LSF at multivariate analysis. For other liver tumors, tumor size (P = .001) and tumor burden (P = .003) were significantly associated with different LSF categories at univariate analysis. Multivariate confirmation was precluded by small sample size. Patients underwent a median of one (90)Y RE session (range, one to six), with median per-treatment and cumulative lung doses of 6.0 Gy and 8.5 Gy, respectively. CONCLUSION: LSF greater than 20% periodically occurs in HCC but is uncommon in other liver tumors. Specific tumor characteristics are associated with LSF greater than 20% and may indicate need for interventions to reduce LSF.

Characterization of liver function parameter alterations after transjugular intrahepatic portosystemic shunt creation and association with early mortality.

OBJECTIVE: The purpose of this article is to characterize the temporal evolution and clinical impact of laboratory liver function parameters after transjugular intrahepatic portosystemic shunt (TIPS) creation. MATERIALS AND METHODS: In this single-institution retrospective study, 157 patients (98 men and 59 women; median age, 55 years) underwent TIPS between 2000 and 2012 and had 1-month hepatobiliary laboratory follow-up. Medical record review was used to compare baseline, peak, and low bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, and international normalized ratio (INR) levels within 30 days after TIPS in surviving and dying patients to assess laboratory responses to shunt creation. RESULTS: TIPSs were created with a hemodynamic success rate of 98%, with median pressure gradient reduction of 13 mm Hg. Ninety-day mortality was 21%. Hepatobiliary laboratory values showed significant increases in the days after TIPS compared with baseline levels (bilirubin, 1.6 vs 3.5 mg/dL; AST, 49 vs 149 U/L; ALT, 26 vs 90 U/L; alkaline phosphatase, 97 vs 177 U/L; and INR, 1.5 vs 2.0; p<0.05 in all cases). Patients surviving to 90 days experienced statistically significant but transient laboratory value elevations-up to twofold over baseline-within days of TIPS, whereas patients dying within 90 days experienced three-to fourfold increases over a longer period that did not return to baseline. Differences in laboratory evolution were statistically significant in surviving versus dying patients. CONCLUSION: TIPS results in acute transient elevation of hepatobiliary enzymes, which may be more pronounced in patients with early mortality. An exaggerated laboratory elevation in excess of threefold greater than baseline or a prolonged increase exceeding 1 week may herald poorer clinical outcome.

Efficacy and safety of flow-directed pulmonary artery catheter thrombolysis for treatment of submassive pulmonary embolism.

OBJECTIVE: The purpose of this study was to assess the efficacy and safety of flow-directed catheter thrombolysis for treatment of submassive pulmonary embolism (PE). MATERIALS AND METHODS: In this single-institution retrospective study, 19 patients (nine men and 10 women; mean age [± SD], 54 ± 13 years) with submassive PE underwent catheter-directed thrombolysis between 2009 and 2013. Presenting symptoms included dyspnea in 18 of 19 (95%) cases. Submassive PE was diagnosed by pulmonary CT arteriography and right ventricular strain. PE was bilateral in 17 of 19 (89%) and unilateral in two of 19 (11%) cases. Thrombolysis was performed via a pulmonary artery (PA) catheter infusing 0.5- 1.0 mg alteplase per hour and was continued to complete or near complete clot dissolution with reduction in PA pressure. IV systemic heparin was administered. Measured outcomes included procedural success, PA pressure reduction, clinical success, survival, and adverse events. RESULTS: Procedural success, defined as successful PA catheter placement, fibrinolytic agent delivery, PA pressure reduction, and achievement of complete or near complete clot dissolution, was achieved in 18 of 19 (95%) cases. Thrombolysis required 57 ± 31 mg of alteplase administered over 89 ± 32 hours. Initial and final PA pressures were 30 ± 10 mm Hg and 20 ± 8 mm Hg (p < 0.001). All 18 (100%) technically successful cases achieved clinical success because all patients experienced symptomatic improvement. Eighteen of 19 (95%) patients survived to hospital discharge; 18 of 19 (95%) and 15 of 16 (94%) patients had documented 1-month and 3-month survival. One fatal case of intracranial hemorrhage was attributed to supratherapeutic anticoagulation because normal fibrinogen levels did not suggest remote fibrinolysis; procedural success was not achieved in this case because of early thrombolysis termination. No other complications were encountered. CONCLUSION: Among a small patient cohort, flow-directed catheter thrombolysis with alteplase effectively dissolved submassive PE and reduced PA pressure. Postprocedure short-term survival was high, and patients undergoing thrombolysis required close observation for bleeding events.

Right atrial pressure may impact early survival of patients undergoing transjugular intrahepatic portosystemic shunt creation.

PURPOSE: To elucidate the impact of right atrial (RA) pressure on early mortality after transjugular intrahepatic portosystemic shunt (TIPS). MATERIAL AND METHODS: In this single institution retrospective study, 125 patients (M:F = 75:50, mean age 55 years) who underwent TIPS with recorded intra-procedural RA pressures between 1999-2012 were studied. Demographic (age, gender), liver disease (Child-Pugh, Model for End Stage Liver Disease or MELD score), and procedure (indication, urgency, Stent type, portosystemic gradient or PSG reduction, baseline and post-TIPS RA pressure) data were identified, and the influence of these parameters on 30- and 90-day mortality was assessed using binary logistic regression. RESULTS: TIPS were created for variceal hemorrhage (n = 55) and ascites (n = 70). Hemodynamic success rate was 99% (124/125) and mean PSG reduction was 13 mmHg. 30- and 90-day mortality rates were 18% (19/106) and 28% (29/106). Baseline and final RA pressure were significantly associated with 30- (12 vs. 15 mmHg, P = 0.021; 18 vs. 21 mmHg, P = 0.035) and 90-day (12 vs. 14 mmHg, P = 0.022; 18 vs. 20 mmHg, P = 0.024) survival on univariate analysis. Predictive usefulness of RA pressure was not confirmed in multivariate analyses. Area under receiver operator characteristic (AUROC) curve analysis revealed good pre- and post-TIPS RA pressure predictive capacity for 30- (0.779, 0.810) and 90-day (0.813, 0.788) mortality among variceal hemorrhage patients at 14.5 and 21.5 mm Hg thresholds. CONCLUSION: Intra-procedural RA pressure may have predictive value for early post-TIPS mortality. Pre-procedure consideration and optimization of patient cardiac status may enhance candidate selection, risk stratification, and clinical outcomes, particularly in variceal hemorrhage patients.

Conventional and spectral- CT for renal cell carcinoma thermal ablation: A case report.

Dual-energy or spectral computed tomography (CT) information may be obtained by either sending X-ray beams of different energy spectra through the patient or by discriminating the energy of the X-rays that reach the detector. The spectral signal is then used to generate multiple results: conventional, virtual monoenergetic (MonoE), effective atomic number, electron density, and other material specific (e.g., iodine, calcium, or uric acid). This report demonstrates the potential benefits of spectral CT imaging during percutaneous tumor ablation procedures, specifically regarding visualization of inconspicuous tumors, accurate probe placement, and assessment of treatment efficacy.

Deep convolutional-neural-network-based metal artifact reduction for CT-guided interventional oncology procedures (MARIO).

BACKGROUND: Computed tomography (CT) is routinely used to guide cryoablation procedures. Notably, CT-guidance provides 3D localization of cryoprobes and can be used to delineate frozen tissue during ablation. However, metal-induced artifacts from ablation probes can make accurate probe placement challenging and degrade the ice ball conspicuity, which in combination could lead to undertreatment of potentially curable lesions. PURPOSE: In this work, we propose an image-based neural network (CNN) model for metal artifact reduction for CT-guided interventional procedures. METHODS: An image domain metal artifact simulation framework was developed and validated for deep-learning-based metal artifact reduction for interventional oncology (MARIO). CT scans were acquired for 19 different cryoablation probe configurations. The probe configurations varied in the number of probes and the relative orientations. A combination of intensity thresholding and masking based on maximum intensity projections (MIPs) was used to segment both the probes only and probes + artifact in each phantom image. Each of the probe and probe + artifact images were then inserted into 19 unique patient exams, in the image domain, to simulate metal artifact appearance for CT-guided interventional oncology procedures. The resulting 361 pairs of simulated image volumes were partitioned into disjoint training and test datasets of 304 and 57 volumes, respectively. From the training partition, 116 600 image patches with a shape of 128 × 128 × 5 pixels were randomly extracted to be used for training data. The input images consisted of a superposition of the patient and probe + artifact images. The target images consisted of a superposition of the patient and probe only images. This dataset was used to optimize a U-Net type model. The trained model was then applied to 50 independent, previously unseen CT images obtained during renal cryoablations. Three board-certified radiologists with experience in CT-guided ablations performed a blinded review of the MARIO images. A total of 100 images (50 original, 50 MARIO processed) were assessed across different aspects of image quality on a 4-point likert-type item. Statistical analyses were performed using Wilcoxon signed-rank test for paired samples. RESULTS: Reader scores were significantly higher for MARIO processed images compared to the original images across all metrics (all p < 0.001). The average scores of the overall image quality, iceball conspicuity, overall metal artifact, needle tip visualization, target region confidence, and worst metal artifact, needle tip visualization, iceball conspicuity, and target region confidence improved by 34.91%, 36.29%, 39.94%, 34.17%, 35.13%, and 45.70%, respectively. CONCLUSIONS: The proposed method of image-based metal artifact simulation can be used to train a MARIO algorithm to effectively reduce probe-related metal artifacts in CT-guided cryoablation procedures.

Transarterial sorafenib chemoembolization: preliminary study of technical feasibility in a rabbit model.

PURPOSE: To test the feasibility of targeted intraarterial administration of the tyrosine kinase inhibitor chemotherapeutic agent sorafenib to inhibit embolotherapy-induced tumor angiogenesis and reduce systemic drug side effects. MATERIALS AND METHODS: The left hepatic lobes of five New Zealand White rabbits (mean weight, 2.7 kg±0.2) were treated with chemoembolization with sorafenib and ethiodized oil emulsion, followed by immediate euthanasia. Postprocedure noncontrast computed tomography (CT) was used to evaluate intrahepatic chemotherapy mixture distribution. Liquid chromatography/tandem mass spectrometry (LC-MS/MS) was then used to directly measure sorafenib concentration in the treated liver tissue. Histopathologic assessment of treated left lobes was performed to identify any immediate toxic effects of the sorafenib solution. RESULTS: Lobar sorafenib chemoembolization was successfully performed in all cases via the left hepatic artery. Sorafenib and ethiodized oil (mean, 6.4 mg±3.8 and 0.95 mL±0.7, respectively) were injected, and CT confirmed targeted left hepatic lobe sorafenib emulsion delivery in all cases. Corresponding LC-MS/MS analysis yielded a mean sorafenib concentration of 94.2 µg/mL±48.3 in treated left lobe samples (n = 5), significantly greater than typical therapeutic drug levels (2-10 µg/mL) achieved with oral sorafenib systemic therapy. Histopathologic assessment showed only mild or moderate nonspecific ballooning degeneration in zone 3 hepatocytes, without tissue necrosis. CONCLUSIONS: Targeted transarterial sorafenib delivery is feasible and results in higher tissue drug levels than reported for systemic sorafenib therapy, without immediate histopathologic tissue toxicity. Future studies should aim to determine the utility of sorafenib chemoembolization in reducing hypoxia-induced vasculogenesis in liver tumors.