Computed Tomography Evaluation of In Vivo Pulmonary Cryoablation Zone Sizes.

PURPOSE: To evaluate ablation zone sizes in patients undergoing pulmonary tumor cryoablation with 14-gauge cryoablation probes. MATERIALS AND METHODS: A single-center retrospective analysis of all consecutive patients who underwent cryoablation of pulmonary tumors with 1 or more 14-gauge probes (August 2017 to June 2020) was performed. Intraprocedural and 1-2-month postprocedural chest computed tomography (CT) scans were evaluated to characterize pulmonary lesions, ice balls, and ablation zones. Single-probe 14-gauge ablation zone volumes were compared with manufacturer reference isotherms and single- and 2-probe ablation zones from a prior investigation of 17-gauge probes. Overall survival and local recurrence-free survival were calculated to 3 years. RESULTS: Forty-seven pulmonary malignancies in 42 patients (women, 50%; mean age, 75.2 years ± 11.5) underwent cryoablation with 1 (n = 35), 2 (n = 10), or 3 (n = 2) cryoablation probes. One- to 2-month follow-up CT images were available for 30 of the 42 patients. The mean cryoablation zone volumes at 1-2 months when 1 (n = 21), 2 (n = 8), and 3 (n = 1) probes were used were 5.0 cm3 ± 2.3, 37.5 cm3 ± 20.5, and 28.4 cm3, respectively. The mean single-probe follow-up ablation zone volume was larger than that previously reported for 17-gauge probes (3.0 cm3 ± 0.3) (P < .001) but smaller than manufacturer-reported isotherms (11.6 cm3 for -40 °C isotherm) and the 2-probe ablation zone volume with 17-gauge devices (12.9 cm3 ± 2.4) (for all, P < 001). The 3-year overall survival and local recurrence-free survival were 69% (95% confidence interval [CI], 53%-89%) and 87% (95% CI, 74%-100%), respectively. CONCLUSIONS: Fourteen-gauge probes generate larger ablation volumes than those generated by 17-gauge probes. Manufacturer-reported isotherms are significantly larger than actual cryoablation zones. Cryoablation can attain low rates of local recurrence.

Incorporation of a Social Virtual Reality Platform into the Residency Recruitment Season.

RATIONALE AND OBJECTIVES: The Covid-19 pandemic ushered a sudden need for residency programs to develop innovative socially distant and remote approaches to effectively promote their program. Here we describe our experience using the social virtual reality (VR) platform Mozilla Hubs for the pre-interview social during the 2020-2021 radiology residency virtual recruitment season, provide results of a survey sent to assess applicants' attitudes towards the VR pre-interview social, and outline additional use-cases for the emerging technology. MATERIALS AND METHODS: A VR Meeting Hall dedicated to the pre-interview social was designed in Mozilla Hubs. To assess applicants' impressions of the Mozilla Hubs pre-interview social, applicants were sent an optional web-based survey. Survey respondents were asked to respond to a series of eleven statements using a five-point Likert scale of perceived agreement: Strongly Agree, Agree, Neutral, Disagree, Strongly Disagree. Statements were designed to gauge applicants' attitudes towards the Mozilla Hubs pre-interview social and its usefulness in helping them learn about the residency program, particularly in comparison with pre-interview socials held on conventional video conferencing software (CVCS). RESULTS: Of the 120 residency applicants invited to the Mozilla Hubs pre-interview social, 111 (93%) attended. Of these, 68 (61%) participated in the anonymous survey. Most applicants reported a better overall experience with Mozilla Hubs compared to CVCS (47/68, 69%), with 10% (7/68) reporting a worse overall experience, and 21% (14/68) neutral. Most applicants reported the Mozilla Hubs pre-interview social allowed them to better assess residency culture than did pre-interview socials using CVCS (41/68, 60%). Seventy-two percent of applicants reported that the Mozilla Hubs pre-interview social positively impacted their decision to strongly consider the residency program (49/68). CONCLUSION: Radiology residency applicants overall preferred a pre-interview social hosted on a social VR platform, Mozilla Hubs, compared to those hosted on CVCS. Applicants reported the use of a social VR platform reflected positively on the residency and positively impacted their decision to strongly consider the program.

MRI-Derived Sarcopenia Associated with Increased Mortality Following Yttrium-90 Radioembolization of Hepatocellular Carcinoma.

PURPOSE: To evaluate the influence of sarcopenia on survival in patients with hepatocellular carcinoma (HCC) treated with 90Y radioembolization. MATERIALS AND METHODS: This single-center retrospective cohort study analyzed 82 consecutive patients (65 men and 17 women, mean age 65 years, range 31-83 years) with HCC treated with 90Y radioembolization between December 2013 and December 2017. Sarcopenia was assessed on pre-procedure MRI performed within 100 days prior to 90Y radioembolization by segmenting the paraspinal musculature at the level of the superior mesenteric artery origin and subtracting fat-intensity pixels to yield fat-free muscle area (FFMA). Sarcopenia was defined as FFMA ≤31.97 cm2 for men and ≤28.95 cm2 for women. Survival at 90 days, 180 days, 1 year, and 3 years following initial treatment was assessed using medical and public obituary records. RESULTS: Sarcopenia was identified in 30% (25/82) of patients. Death was reported for 49% (32/65) of males and 71% (8/17) of females (mean follow-up 19.6 months, range 21 days-58 months). Patients with sarcopenia were found to have increased mortality at 180 days (31.8% vs. 8.9%) and 1 year (68.2% vs. 21.2%). Sarcopenia was an independent predictor of mortality adjusted for BCLC stage and sub-analysis demonstrated that sarcopenia independently predicted increased mortality for patients with BCLC stage B disease. CONCLUSION: Sarcopenia was associated with increased 180-day and 1-year mortality in HCC patients undergoing 90Y radioembolization. Sarcopenia was an independent predictor of survival adjusted for BCLC stage with significant deviation in the survival curves of BCLC stage B patients with and without sarcopenia.

Changing National Medicare Utilization of Catheter, Computed Tomography, and Magnetic Resonance Extremity Angiography: A Specialty-focused 16-Year Analysis.

To assess changing utilization of extremity angiography from 2001 to 2016, focusing on modalities and provider specialties. Medicare PSPS Master Files from 2001-2016 and POSPUF from 2016 were used to determine overall and specialty utilization of diagnostic catheter angiography (DCA), CT angiography (CTA), and MR angiography (MRA). From 2001 to 2016, extremity angiography increased from 1107 to 1590 extremities imaged per 100,000 beneficiaries, with rapid expansion of CTA (22 in 2001 to 619 in 2009; plateau of 645 in 2016), but declines in DCA (1039 to 914) and MRA (45 to 30). Over time, extremity angiography shifted from 94% DCA, 4% MRA, and 2% CTA to 58% DCA, 41% CTA, and 2% MRA. For radiologists, extremity angiography increased slightly (741 to 767) with increases in CTA (20 to 595) and large decreases in DCA (681 to 145), with MRA remaining low (40 to 27). Extremity angiography increased for cardiologists (197 to 349) and vascular surgeons (87 to 351), both overwhelmingly performing DCA. Radiologists' share of all extremity angiography shifted from 67% to 48%, with interventionalists (47%), generalists (43%), and abdominal radiologists (7.4%) providing most radiologist services in 2016. Throughout, radiologists were the dominant providers of CTA (89% to 92%) and MRA (89% to 90%). Extremity angiography utilization in Medicare beneficiaries increased nearly 50% from 2001 to 2016, largely related to CTA performed by radiologists. Of radiologists, interventionalists and generalists together render most services. Cardiologists and surgeons assumed a large share of DCA previously performed by radiologists.

Catheter-directed Thrombolysis for Neonatal IVC and Bilateral Renal Vein Thrombosis: A Case Report.

Renal vein thrombosis is the most common non-catheter-associated venous thromboembolism event in neonates, accounting for up to 20% of cases. Although mortality rates are lower than a variety of other forms of pediatric thrombosis, renal vein thrombi are associated with significant short-term and long-term sequelae. This report presents the case of a full-term neonate presenting with bilateral renal vein thrombosis with inferior vena cava involvement treated with catheter-directed thrombolysis. This case report intends to highlight the value of a multidisciplinary approach to pediatric venous thromboembolism and to outline relevant procedural details and current laboratory and imaging monitoring of catheter-directed thrombolysis.

Preliminary Results of Lung Cancer Screening in a Socioeconomically Disadvantaged Population.

OBJECTIVE: The objective of our study was to describe the preliminary results of our clinical low-dose CT (LDCT) lung cancer screening program targeting a minority, socioeconomically disadvantaged, high-risk population different from that studied in the National Lung Screening Trial (NLST). MATERIALS AND METHODS: Community partner clinics in an underserved region of south Los Angeles County referred interested candidates to our program. All patients met National Comprehensive Cancer Network eligibility criteria for lung cancer screening. RESULTS: From July 21, 2015, through April 3, 2017, 889 individuals were referred to the program. Of the 329 eligible participants, 275 (mean age, 59 years; 52% men) underwent baseline screening LDCT: 84% of patients were black, and 66% had a high school education or less. The median pack-years was 40, and 81% of patients were current smokers. Thirty-one percent of participants reported occupational exposure to one or more known lung carcinogens. Lung CT Screening Reporting and Data System (Lung-RADS) categories were assigned using baseline LDCT examinations: Lung-RADS category 1 or 2 were assigned in 86% of patients, category 3 in 7%, category 4A in 4%, and category 4B or 4X in 3%. Lung cancer has been diagnosed in two of these patients (0.7%) to date: stage IIIB small cell lung carcinoma in one patient and stage IV lung cancer of unknown type in the other patient. Among the 275 patients, 29% had potentially clinically significant incidental findings. CONCLUSION: Lung cancer screening with LDCT in a minority, socioeconomically disadvantaged, high-risk population is feasible but may yield a different lung cancer profile than screening populations in more privileged communities. More follow-up time is required to determine whether the reduction in lung cancer mortality shown in the NLST applies to this underserved population.

Intra-arterial contrast-enhanced ultrasound (IA CEUS) for localization of hepatocellular carcinoma (HCC) supply during transarterial chemoembolization (TACE): a case series.

Transarterial chemoembolization (TACE) is a proven catheter-based locoregional therapy for treatment of hepatocellular carcinoma (HCC). Drug-eluting bead TACE involves delivering micrometer-sized particles preloaded with doxorubicin directly to the tumor via its arterial blood supply and results in vascular embolization with intra-tumoral drug release. Effective therapy requires mapping of the tumor arterial supply, which in some cases cannot be accomplished with conventional angiographic techniques alone. Contrast-enhanced ultrasound (CEUS) is an imaging technique which utilizes microbubble contrast agents to demonstrate blood flow and tissue perfusion, enabling tumor visualization in real time. CEUS with intravenous contrast administration is well established for evaluation of HCC. Intra-arterial (IA) CEUS, on the other hand, is an emerging technique that allows more selective evaluation of the arterial supply to the tumor. The three cases in this report illustrate the utility of intra-procedural IA CEUS during TACE. Specifically, IA CEUS aided TACE in cases where the HCC showed poor arterial enhancement, an extrahepatic arterial supply, and a portal venous supply, respectively.

Percutaneous Lung Biopsy in the Molecular Profiling Era: A Survey of Current Practices.

PURPOSE: This study aimed to assess the current practice patterns of radiologists performing percutaneous lung biopsies. MATERIALS AND METHODS: This cross-sectional study used a web-based survey sent to the Society of Thoracic Radiology membership from August to October 2015. Responses were collected anonymously, and results were tallied. RESULTS: A total of 244 Society of Thoracic Radiology members responded to the survey. One hundred thirty-seven radiologists regularly perform percutaneous lung biopsies, of whom 102 (74%) practice at an academic teaching hospital. Computed tomography (CT) and CT fluoroscopy were the modalities of choice for image guidance, preferred by 82 (60%) and 48 (35%) respondents, respectively. Twenty (15%) respondents preferred fine-needle aspiration (FNA) alone, 57 (42%) preferred core needle biopsy (CNB) alone, and 59 (43%) preferred both FNA and CNB in the same setting. On-site cytology was routinely requested by 70 (71%) respondents with access to such services. In cases of suspected lung cancer, 79 (60%) respondents estimated sending tissue for molecular analysis >25% of the time. Forty-three (32%) respondents reported using intraprocedural preventive measures to minimize risk of pneumothorax. CONCLUSIONS: Among surveyed radiologists who perform percutaneous lung biopsies, most utilize CT guidance with either CNB alone or in conjunction with FNA. A small minority routinely performs FNA alone, which may negatively impact diagnostic accuracy and provide insufficient tissue for molecular profiling. Education of all radiologists regarding the importance of routinely acquiring and sending greater amounts of tissue for molecular/genomic assessment of suspected lung cancer is needed.