Ablation of Stage I-II Non-Small Cell Lung Cancer in Patients With Interstitial Lung Disease: A Multicenter Retrospective Study.

BACKGROUND. Treatment options for patients with interstitial lung disease (ILD) who develop stage I-II non-small cell lung cancer (NSCLC) are severely limited, given that surgical resection, radiation, and systemic therapy are associated with significant morbidity and mortality. OBJECTIVE. The aim of this study was to evaluate the safety and efficacy of percutaneous ablation of stage I-II NSCLC in patients with ILD. METHODS. This retrospective study included patients with ILD and stage I-II NSCLC treated with percutaneous ablation in three health systems between October 2004 and February 2023. At each site, a single thoracic radiologist, blinded to clinical outcomes, reviewed preprocedural chest CT examinations for the presence and type of ILD according to 2018 criteria proposed by the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Latin American Thoracic Society. The primary outcome was 90-day major (grade ≥ 3) adverse events, based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Secondary outcomes were hospital length of stay (HLOS), local tumor control, and overall survival (OS). RESULTS. The study included 33 patients (19 men, 14 women; median age, 78 years; 16 patients with Eastern Cooperative Oncology Group performance status ≤ 1) with ILD who underwent 42 percutaneous ablation sessions (21 cryoablations, 11 radiofrequency ablations, 10 microwave ablations) of 43 NSCLC tumors ((median tumor size, 1.6 cm; IQR, 1.4-2.5 cm; range, 0.7-5.4 cm; 37 stage I, six stage II). The extent of lung fibrosis was 20% or less in 24 patients; 17 patients had imaging findings of definite or probable usual interstitial pneumonia. The 90-day major adverse event rate was 14% (6/42), including one CTCAE grade 4 event. No acute ILD exacerbation or death occurred within 90 days after ablation. The median HLOS was 1 day (IQR, 0-2 days). Median imaging follow-up for local tumor control was 17 months (IQR, 11-32 months). Median imaging or clinical follow-up for OS was 16 months (IQR, 6-26 months). Local tumor control and OS were 78% and 77%, respectively, at 1 year and 73% and 46% at 2 years. CONCLUSION. Percutaneous ablation appears to be a safe and effective treatment option for stage I-II NSCLC in the setting of ILD after multidisciplinary selection. CLINICAL IMPACT. Patients with ILD and stage I-II NSCLC should be considered for percutaneous ablation given that they are frequently ineligible for surgical resection, radiation, and systemic therapy.

Can incorrect artificial intelligence (AI) results impact radiologists, and if so, what can we do about it? A multi-reader pilot study of lung cancer detection with chest radiography.

OBJECTIVE: To examine whether incorrect AI results impact radiologist performance, and if so, whether human factors can be optimized to reduce error. METHODS: Multi-reader design, 6 radiologists interpreted 90 identical chest radiographs (follow-up CT needed: yes/no) on four occasions (09/20-01/22). No AI result was provided for session 1. Sham AI results were provided for sessions 2-4, and AI for 12 cases were manipulated to be incorrect (8 false positives (FP), 4 false negatives (FN)) (0.87 ROC-AUC). In the Delete AI (No Box) condition, radiologists were told AI results would not be saved for the evaluation. In Keep AI (No Box) and Keep AI (Box), radiologists were told results would be saved. In Keep AI (Box), the ostensible AI program visually outlined the region of suspicion. AI results were constant between conditions. RESULTS: Relative to the No AI condition (FN = 2.7%, FP = 51.4%), FN and FPs were higher in the Keep AI (No Box) (FN = 33.0%, FP = 86.0%), Delete AI (No Box) (FN = 26.7%, FP = 80.5%), and Keep AI (Box) (FN = to 20.7%, FP = 80.5%) conditions (all ps < 0.05). FNs were higher in the Keep AI (No Box) condition (33.0%) than in the Keep AI (Box) condition (20.7%) (p = 0.04). FPs were higher in the Keep AI (No Box) (86.0%) condition than in the Delete AI (No Box) condition (80.5%) (p = 0.03). CONCLUSION: Incorrect AI causes radiologists to make incorrect follow-up decisions when they were correct without AI. This effect is mitigated when radiologists believe AI will be deleted from the patient's file or a box is provided around the region of interest. CLINICAL RELEVANCE STATEMENT: When AI is wrong, radiologists make more errors than they would have without AI. Based on human factors psychology, our manuscript provides evidence for two AI implementation strategies that reduce the deleterious effects of incorrect AI. KEY POINTS: • When AI provided incorrect results, false negative and false positive rates among the radiologists increased. • False positives decreased when AI results were deleted, versus kept, in the patient's record. • False negatives and false positives decreased when AI visually outlined the region of suspicion.

Artificial intelligence for prediction of COVID-19 progression using CT imaging and clinical data.

OBJECTIVES: Early recognition of coronavirus disease 2019 (COVID-19) severity can guide patient management. However, it is challenging to predict when COVID-19 patients will progress to critical illness. This study aimed to develop an artificial intelligence system to predict future deterioration to critical illness in COVID-19 patients. METHODS: An artificial intelligence (AI) system in a time-to-event analysis framework was developed to integrate chest CT and clinical data for risk prediction of future deterioration to critical illness in patients with COVID-19. RESULTS: A multi-institutional international cohort of 1,051 patients with RT-PCR confirmed COVID-19 and chest CT was included in this study. Of them, 282 patients developed critical illness, which was defined as requiring ICU admission and/or mechanical ventilation and/or reaching death during their hospital stay. The AI system achieved a C-index of 0.80 for predicting individual COVID-19 patients' to critical illness. The AI system successfully stratified the patients into high-risk and low-risk groups with distinct progression risks (p < 0.0001). CONCLUSIONS: Using CT imaging and clinical data, the AI system successfully predicted time to critical illness for individual patients and identified patients with high risk. AI has the potential to accurately triage patients and facilitate personalized treatment. KEY POINT: • AI system can predict time to critical illness for patients with COVID-19 by using CT imaging and clinical data.

Interstitial lung disease is a dominant feature in patients with circulating myositis-specific antibodies.

BACKGROUND: Many patients with polymyositis (PM) or dermatomyositis (DM) have circulating myositis-specific antibodies (MSAs). Interstitial lung disease (ILD) is a common manifestation of PM/DM, and it can even precede the onset of characteristic muscle or skin manifestations. Furthermore, there appear to be some patients with ILD and circulating MSAs who do not develop muscle or skin disease even after prolonged follow-up. We sought to determine whether ILD is equally or more common than myositis or dermatitis at the time of initial detection of MSAs. METHODS: We identified all patients found to have circulating MSAs at our institution over a 4-year period and assessed for the presence of lung, muscle, and skin disease at the time of initial detection of MSAs. Among those found to have ILD, we compared demographic and clinical features, chest CT scan findings, and outcomes between those with PM/DM-associated ILD and those with ILD but no muscle or skin disease. RESULTS: A total of 3078 patients were tested for MSAs, and of these 40 were positive. Nine different MSAs were detected, with anti-histidyl tRNA synthetase (anti-Jo-1) being the most common (35% of MSAs). Among patients with positive MSAs, 86% were found to have ILD, compared to 39% and 28% with muscle and skin involvement, respectively (p < 0.001). Fifty percent of all MSA-positive patients had isolated ILD, with no evidence of muscle or skin disease. Those with isolated ILD were more likely to be older and have fibrotic changes on chest CT, less likely to receive immunomodulatory therapy, and had worse overall survival. CONCLUSIONS: In this study we found that individuals with circulating MSAs were more likely to have ILD than classic muscle or skin manifestations of PM/DM at the time of initial detection of MSAs. Our findings suggest that the presence of ILD should be considered a disease-defining manifestation in the presence of MSAs and incorporated into classification criteria for PM/DM.

Cardiothoracic Complications of Immune Checkpoint Inhibitor Therapy: An Imaging Review.

Immune checkpoint inhibitor therapy has revolutionized the treatment of many different types of cancer. However, despite dramatic improvements in tumor oncologic response and patient outcomes, immune checkpoint blockade has been associated with multiple distinctive side-effects termed immune-related adverse events. These often have important clinical implications because these can vary in severity, sometimes even resulting in death. Therefore, it is important for both radiologists and clinicians to recognize and be aware of these reactions to help appropriately guide patient management. This article specifically highlights imaging manifestations of the most common cardiothoracic toxicities of these agents, including pneumonitis, sarcoid-like granulomatosis and lymphadenopathy, and myocarditis.

Percutaneous Thermal Ablation for Lung Cancer: An Update.

Lung cancer remains the leading cause of cancer death in the United States, and accounts for more deaths than breast, colon, and prostate cancer combined. Over the past decade, percutaneous thermal ablative therapy (PTA) has become a useful adjunctive therapy in combination with longer-standing methods, or as a standalone treatment. The physiologic basis of thermal ablation is that coagulative necrosis and cell death occur at temperatures above 60°C. During treatment, PTA of lung tumors routinely achieves temperatures above 70°C. Radiofrequency ablation has fallen out of favor in recent years as microwave ablation has been proven to be effective, with shorter treatment times. Pulmonary PTA is a routine outpatient procedure in which conscious sedation is used in lieu of general anesthesia. The first post-procedural follow-up imaging is CT at 4 weeks, coinciding with an office visit. In our most recent review of long-term results, which included 108 patients, all-cause survival at 1, 2, and 3 years was 83%, 59%, and 43%, respectively. When we specifically considered cancer-related survival, these numbers increased to 94%, 79%, and 57%. Percutaneous thermal ablation has been shown to be a safe and effective treatment for patients with early-stage NSCLC who are not candidates for surgery, as well as a potential treatment for local small cell lung cancers. As the field of oncology, and specifically the treatment of lung cancer, continues to evolve, PTA will represent a useful tool in the arsenal.

Cancer Yield of Incidental Breast Lesions Detected on Chest Computed Tomography.

OBJECTIVE: This study aimed to determine the cancer yield for abnormal breast findings initially identified on chest computed tomography (CT). MATERIALS AND METHODS: This institutional review board-approved, Health Insurance Portability and Accountability Act-compliant study retrospectively reviewed reports of 41,217 consecutive chest CT examinations done from January 1, 2006, to December 31, 2011, to identify those with breast findings noted in the impression of the report. Examinations done for staging of newly diagnosed breast cancer were excluded. The electronic medical record was searched for any subsequent breast imaging and any corresponding pathology results. Cancer yield was calculated. RESULTS: A total of 258 chest CT examinations with abnormal breast findings were identified in 218 unique patients. Average patient age was 65.6 years (range, 30-100 years). There were 207 women and 11 men. Of these, 75 patients had follow-up breast imaging in our system. One hundred forty-three patients did not have follow-up in our system and were excluded for purposes of cancer detection rate calculation. Thirteen of 75 patients were found to have lesions that were malignant: infiltrating ductal carcinoma (8), invasive lobular carcinoma (2), lymphoma (2), and intracystic papillary cancer with atypical features (1). Four of 75 patients underwent further workup and were found to have lesions that were benign: fibroadenoma (3) and benign fibrocystic change (1). The remainder of the 58 of 75 patients had dedicated breast imaging that was classified as either Breast Imaging Reporting and Data System score 1 or 2, and no further workup was performed. Cancer yield from CT findings was 17.3%. CONCLUSIONS: Abnormal CT findings in the breast warrant additional evaluation with dedicated breast imaging to evaluate for a possible underlying malignancy. Cancer yield from CT findings in this study was 17.3%.

Financial Impact of Incentive Spirometry.

Despite largely unproven clinical effectiveness, incentive spirometry (IS) is widely used in an effort to reduce postoperative pulmonary complications. The objective of the study is to evaluate the financial impact of implementing IS. The amount of time nurses and RTs spend each day doing IS-related activities was assessed utilizing an online survey distributed to the relevant national nursing and respiratory therapists (RT) societies along with questionnaire that was prospectively collected every day for 4 weeks at a single 10-bed cardiothoracic surgery step-down unit. Cost of RT time to teach IS use to patients and cost of nurse time spent reeducating and reminding patients to use IS were used to calculate IS implementation cost estimates per patient. Per-patient cost of IS implementation ranged from $65.30 to $240.96 for a mean 9-day step-down stay. For the 566 patients who stayed in the 10-bed step-down in 2016, the total estimated cost of implementing IS ranged from $36 959.80 to $136 383.36. Using national survey workload data, per-patient cost of IS implementation costed $107.36 (95% confidence interval [CI], $97.88-$116.98) for a hospital stay of 4.5 days. For the 9.7 million inpatient surgeries performed annually in the United States, the total annual cost of implementing postoperative IS is estimated to be $1.04 billion (95% CI, $949.4 million-$1.13 billion). The cost of implementing IS is substantial. Further efficacy studies are necessary to determine whether the cost is justifiable.

Microwave Ablation for Lung Neoplasms: A Retrospective Analysis of Long-Term Results.

PURPOSE: To determine the long-term safety and efficacy of microwave (MW) ablation in the treatment of lung tumors at a single academic medical center. MATERIALS AND METHODS: Retrospective review was performed of 108 patients (42 female; mean age, 72.5 y ± 10.3 [standard deviation]) who underwent computed tomography (CT)-guided percutaneous MW ablation for a single lung malignancy. Eighty-two were primary non-small-cell lung cancers and 24 were metastatic tumors (9 colorectal carcinoma, 2 renal-cell carcinoma, 4 sarcoma, 2 lung, and 7 other). Mean maximum tumor diameter was 29.6 mm ± 17.2. Patient clinical and imaging data were reviewed. Statistical analysis was performed by Kaplan-Meier modeling and logistic regression. RESULTS: Odds of primary technical success were 11.1 times higher for tumors < 3 cm vs those > 3 cm (95% confidence interval [CI], 2.97-41.1; P = .0003). For every millimeter increase in original tumor maximal diameter (OMD), the odds of not attaining success increased by 7% (95% CI, 3%-10%; P = .0002). For every millimeter increase in OMD, the odds of complications increased by 3% (95% CI, 0.1%-5%; P = .04). Median time to tumor recurrence was 62 months (95% CI, 29, upper bound not reached; range, 0.2-96.6 mo). Recurrence rates were estimated at 22%, 36%, and 44% at 1, 2, and 3 years, respectively. Recurrence rates were estimated at 31% at 13 months for tumors > 3 cm and 17% for those < 3 cm. Complications included pneumothorax (32%), unplanned hospital admission (28%), pain (20%), infection (7%), and postablation syndrome (4%). CONCLUSIONS: This study further supports the safe and effective use of MW ablation for the treatment of lung tumors.

Percutaneous Thermal Ablation for Small-Cell Lung Cancer: Initial Experience with Ten Tumors in Nine Patients.

PURPOSE: To evaluate outcomes in a small cohort of patients with local or disseminated small-cell lung cancer (SCLC) who received percutaneous thermal ablation therapy. MATERIALS AND METHODS: Ten biopsy-proven SCLC tumors in 9 consecutive patients (5 men, 4 women; average age, 73.8 y ± 12.4) were retrospectively evaluated. Average tumor sizes were 1.8 cm ± 0.5 and 2.6 cm ± 1.2 among patients with local and disseminated disease, respectively. Microwave and radiofrequency ablation were each used for 5 tumors. None of the patients with local SCLC received adjuvant therapy following thermal ablation. Median follow-up duration was 16 months (range, 2-48 mo). Median and 1-year overall survival (OS) were compared for patients in the local and disseminated disease groups. RESULTS: Median and 1-year OS were better among patients treated for local SCLC compared with disseminated disease (47.0 vs 5.5 mo and 3 [100%] vs 2 [40%], respectively). Pneumothorax occurred in 5 patients (55.6%), and 3 patients received successful outpatient thoracostomy tube placement. No patients were hospitalized, and there were no major complications. CONCLUSIONS: This preliminary analysis suggests favorable outcomes in selected patients with local SCLC who undergo percutaneous thermal ablation without adjuvant therapy.

Rib fractures after percutaneous radiofrequency and microwave ablation of lung tumors: incidence and relevance.

PURPOSE: To retrospectively identify the incidence and probable risk factors for rib fractures after percutaneous radiofrequency ablation (RFA) and microwave ablation (MWA) of neoplasms in the lung and to identify complications related to these fractures. MATERIALS AND METHODS: Institutional review board approval was obtained for this HIPAA-compliant retrospective study. Study population was 163 patients treated with MWA and/or RFA for 195 lung neoplasms between February 2004 and April 2010. Follow-up computed tomographic images of at least 3 months were retrospectively reviewed by board-certified radiologists to determine the presence of rib fractures. Generalized estimating equations were performed to assess the effect that patient demographics, tumor characteristics, treatment parameters, and ablation zone characteristics had on development of rib fractures. Kaplan-Meier curve was used to estimate patients' probability of rib fracture after ablation as a function of time. Clinical parameters (ie, pain in ribs or chest, organ damage caused by fractured rib) were evaluated for patients with confirmed fracture. RESULTS: Rib fractures in proximity to the ablation zone were found in 13.5% (22 of 163) of patients. Estimated probability of fracture was 9% at 1 year and 22% at 3 years. Women were more likely than were men to develop fracture after ablation (P = .041). Patients with tumors closer to the chest wall were more likely to develop fracture (P = .0009), as were patients with ablation zones that involved visceral pleura (P = .039). No patients with rib fractures that were apparently induced by RFA and MWA had organ injury or damage related to fracture, and 9.1% (2 of 22) of patients reported mild pain. CONCLUSION: Rib fractures were present in 13.5% of patients after percutaneous RFA and MWA of lung neoplasms. Patients who had ablations performed close to the chest wall should be monitored for rib fractures.

ACR Lung CT Screening Reporting and Data System, a Systematic Review and Meta-Analysis Before Change in US Preventative Services Taskforce Eligibility Criteria: 2014 to 2021.

OBJECTIVE: To review Lung CT Screening Reporting and Data System (Lung-RADS) scores from 2014 to 2021, before changes in eligibility criteria proposed by the US Preventative Services Taskforce. METHODS: A registered systematic review and meta-analysis was conducted in MEDLINE, Embase, CINAHL, and Web of Science in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines; eligible studies examined low-dose CT (LDCT) lung cancer screening at institutions in the United States and reported Lung-RADS from 2014 to 2021. Patient and study characteristics, including age, gender, smoking status, pack-years, screening timeline, number of individual patients, number of unique studies, Lung-RADS scores, and positive predictive value (PPV) were extracted. Meta-analysis estimates were derived from generalized linear mixed modeling. RESULTS: The meta-analysis included 24 studies yielding 36,211 LDCT examinations for 32,817 patient encounters. The meta-analysis Lung-RADS 1-2 scores were lower than anticipated by ACR guidelines, at 84.4 (95% confidence interval [CI] 83.3-85.6) versus 90% respectively (P < .001). Lung-RADS 3 and 4 scores were both higher than anticipated by the ACR, at 8.7% (95% CI 7.6-10.1) and 6.5% (95% CI 5.707.4), compared with 5% and 4%, respectively (P < .001). The ACR's minimum estimate of PPV for Lung-RADS 3 to 4 is 21% or higher; we observed a rate of 13.1% (95% CI 10.1-16.8). However, our estimated PPV rate for Lung-RADS 4 was 28.6% (95% CI 21.6-36.8). CONCLUSION: Lung-RADS scores and PPV rates in the literature are not aligned with the ACR's own estimates, suggesting that perhaps Lung-RADS categorization needs to be reexamined for better concordance with real-world screening populations. In addition to serving as a benchmark before screening guideline broadening, this study provides guidance for future reporting of lung cancer screening and Lung-RADS data.

Use of endobronchial valves for the treatment of bronchopleural fistulas after thermal ablation of lung neoplasms.

Persistent air leaks resulting from bronchopleural fistulas (BPFs) are a rare but serious side effect of thermal ablation. Traditionally, BPFs are treated with surgery; however, patients receiving ablation are often poor surgical candidates and require minimally invasive treatment. The present report describes four cases of BPFs following ablation, which were treated with endobronchial valves (EBVs). In three of the four patients, the pneumothoraces resolved after valve placement. One patient required further treatment with pleurodesis. EBVs can selectively block inspiratory airflow while allowing expiratory flow with drainage of air and secretions. In select patients, EBVs are a viable treatment option for BPFs.

Heavy Smoking Patients Receiving a Lung Cancer Screen Want to Quit: A Call for Tailored Cessation Interventions.

Background: Lung cancer screening for current or former heavy smokers is now recommended among all asymptomatic adults 50-80 years old with a 20 pack-year history of smoking. However, little is known about the smoking-related attitudes of this population. Method: An assessment was conducted among 1,472 current smokers who presented for an annual lung cancer screen at one of 12 diagnostic imaging sites in Rhode Island between April 2019 and May 2020. Patients were asked about their use of smoking products, interest in quitting, and smoking-related attitudes. Results: Patients smoked a median of 16 cigarettes per day; 86.6% were daily cigarette smokers and 30.1% were daily cigar smokers. In total, 91.4% of patients were, to some degree, interested in quitting smoking and 71.4% were seriously thinking about quitting in the next 6 months or sooner. Patients planned on smoking less regardless of whether their lung screen was positive or negative for cancer, though they were more likely to plan on smoking less if negative (on 0-3 pt Likert scale: 0.31, 95% CI [0.27, 0.34] vs. 0.77, 95% CI [0.72, 0.81]). Confidence in quitting and belief in one's inherent ability to quit smoking varied substantially within the sample. Conclusion: Nearly all current smokers receiving a lung cancer screen have some interest in smoking cessation. Due to the heterogeneity in some smoking-related attitudes, tailored interventions for this population should be tested.

Prognostication of patients with COVID-19 using artificial intelligence based on chest x-rays and clinical data: a retrospective study.

BACKGROUND: Chest x-ray is a relatively accessible, inexpensive, fast imaging modality that might be valuable in the prognostication of patients with COVID-19. We aimed to develop and evaluate an artificial intelligence system using chest x-rays and clinical data to predict disease severity and progression in patients with COVID-19. METHODS: We did a retrospective study in multiple hospitals in the University of Pennsylvania Health System in Philadelphia, PA, USA, and Brown University affiliated hospitals in Providence, RI, USA. Patients who presented to a hospital in the University of Pennsylvania Health System via the emergency department, with a diagnosis of COVID-19 confirmed by RT-PCR and with an available chest x-ray from their initial presentation or admission, were retrospectively identified and randomly divided into training, validation, and test sets (7:1:2). Using the chest x-rays as input to an EfficientNet deep neural network and clinical data, models were trained to predict the binary outcome of disease severity (ie, critical or non-critical). The deep-learning features extracted from the model and clinical data were used to build time-to-event models to predict the risk of disease progression. The models were externally tested on patients who presented to an independent multicentre institution, Brown University affiliated hospitals, and compared with severity scores provided by radiologists. FINDINGS: 1834 patients who presented via the University of Pennsylvania Health System between March 9 and July 20, 2020, were identified and assigned to the model training (n=1285), validation (n=183), or testing (n=366) sets. 475 patients who presented via the Brown University affiliated hospitals between March 1 and July 18, 2020, were identified for external testing of the models. When chest x-rays were added to clinical data for severity prediction, area under the receiver operating characteristic curve (ROC-AUC) increased from 0·821 (95% CI 0·796-0·828) to 0·846 (0·815-0·852; p<0·0001) on internal testing and 0·731 (0·712-0·738) to 0·792 (0·780-0 ·803; p<0·0001) on external testing. When deep-learning features were added to clinical data for progression prediction, the concordance index (C-index) increased from 0·769 (0·755-0·786) to 0·805 (0·800-0·820; p<0·0001) on internal testing and 0·707 (0·695-0·729) to 0·752 (0·739-0·764; p<0·0001) on external testing. The image and clinical data combined model had significantly better prognostic performance than combined severity scores and clinical data on internal testing (C-index 0·805 vs 0·781; p=0·0002) and external testing (C-index 0·752 vs 0·715; p<0·0001). INTERPRETATION: In patients with COVID-19, artificial intelligence based on chest x-rays had better prognostic performance than clinical data or radiologist-derived severity scores. Using artificial intelligence, chest x-rays can augment clinical data in predicting the risk of progression to critical illness in patients with COVID-19. FUNDING: Brown University, Amazon Web Services Diagnostic Development Initiative, Radiological Society of North America, National Cancer Institute and National Institute of Biomedical Imaging and Bioengineering of the National Institutes of Health.

Stabilization of mobile pulmonary nodules during radiofrequency ablation.

OBJECTIVE: Lung tumors can exhibit a high degree of mobility during insertion of radiofrequency applicators owing to both respiratory motion and the inherent characteristics of pulmonary parenchyma. The purpose of this report is to describe a technique used to secure lung tumors during insertion of a radiofrequency applicator. CONCLUSION: As experience with percutaneous imaging-guided radiofrequency ablation increases, technical challenges become increasingly apparent. A technique whereby a mobile pulmonary tumor is anchored prior to placement of the ablation electrode is one method of overcoming such a challenge.

Dots are not clots: the over-diagnosis and over-treatment of PE.

The purpose of this work is to question the conventional theory that all pulmonary emboli (PE) are abnormal, and to test the hypothesis that small peripheral PE are a function of life. Most radiologists report any filling defect, independent of size, as clinically significant PE when detected in the pulmonary arteries. We sought to reinforce the theory that small dots in the pulmonary arteries are not clinically significant clots in the conventional setting. The necessity for anticoagulation should be balanced against the risk of bleeding. This retrospective HIPAA-compliant study was approved by the institutional review board; informed consent was not required. All patients diagnosed with PE by 16-slice or 64-slice multidetector computed tomography (CT) over a 6-month period who also had a lower extremity venous ultrasound (US) performed within 7 days of CT were identified. The study group included 26 women and 24 men (mean, 56 years; range, 21-90 years). The locations of the PE were plotted on a pulmonary arterial diagram, and width of the most proximal clot for each patient was measured. Of 1,273 consecutive CT studies, 101 were positive (7.9%) and 50 patients underwent lower extremity US. Thirty-three (66%) patients had PE in the central pulmonary arteries, of which 19 (58%) had deep vein thrombosis (DVT). Seventeen (34%) patients had peripheral PE; DVT was detected in 0 (0%) patients. The peripheral clots measured 1.0-3.8 mm (mean, 2.5 mm). These clots appeared focal and rounded with a "dot-like" appearance. Peripheral, focal filling defects in the pulmonary arteries, which we termed "dots," are not traditional embolic clots, are not associated with detectable lower-extremity clot load, and may represent "normal" embolic activity originating from the lower extremity venous valves. We suggest that more in-depth understanding about small peripheral PE is needed. The necessity of conventional anticoagulation should be critically reviewed in patients with subsegmental PE and minimal clot burden.

Psychometric Validation of a Nonproprietary Survey of Patient Satisfaction for Use in Outpatient Radiology Centers.

OBJECTIVE: Demonstrate the psychometric evaluation process for and results from our radiology-specific patient experience measure. METHODS: We developed a survey to measure five dimensions of patient experience: (1) appointment, (2) reception, (3) registration, (4) procedure, and (5) facility. Each dimension included three to five questions. Each question was answered using a Likert scale (very dissatisfied to very satisfied). Data on procedure type, facility, radiologist interaction, health rating, survey length, and demographics were collected. The survey was implemented at 12 radiology offices. Analyses were conducted using responses from March 2018 to April 2019. Construct validation of the five dimensions was accomplished using confirmatory factor analysis (CFA). Internal consistency was examined using Cronbach and Guttman analysis. RESULTS: The sample included 20,736 subjects. There was strong evidence for construct validity of the five dimensions of patient experience. The CFA achieved the best fit with the five-factor model relative to other models (comparative fit index: 0.98, standardized root mean square error residual: 0.0307, root mean square error of approximation: 0.0371). There was high internal consistency (Cronbach's α 0.94, Guttman coefficient 0.93). Item analysis showed that no questions were consistently skipped. Eighty-two percent of participants said the survey was not too long. Patients reported high satisfaction on all dimensions of satisfaction across modalities and office sites. DISCUSSION: The CFA and internal consistency analyses provide evidence for this survey having good psychometric properties: construct validity for five dimensions of patient experience and high internal consistency among the items. This survey is intended to be used by, and to benefit, radiology practices and their patients.

Multicenter Study of Metastatic Lung Tumors Targeted by Interventional Cryoablation Evaluation (SOLSTICE).

OBJECTIVE: To assess the safety and local recurrence-free survival in patients after cryoablation for treatment of pulmonary metastases. METHODS: This multicenter, prospective, single-arm, phase 2 study included 128 patients with 224 lung metastases treated with percutaneous cryoablation, with 12 and 24 months of follow-up. The patients were enrolled on the basis of the outlined key inclusion criteria, which include one to six metastases from extrapulmonary cancers with a maximal diameter of 3.5 cm. Time to progression of the index tumor(s), metastatic disease, and overall survival rates were estimated using the Kaplan-Meier method. Complications were captured for 30 days after the procedure, and changes in performance status and quality of life were also evaluated. RESULTS: Median size of metastases was 1.0 plus or minus 0.6 cm (0.2-4.5) with a median number of tumors of 1.0 plus or minus 1.2 cm (one to six). Local recurrence-free response (local tumor efficacy) of the treated tumor was 172 of 202 (85.1%) at 12 months and 139 of 180 (77.2%) at 24 months after the initial treatment. After a second cryoablation treatment for recurrent tumor, secondary local recurrence-free response (local tumor efficacy) was 184 of 202 (91.1%) at 12 months and 152 of 180 (84.4%) at 24 months. Kaplan-Meier estimates of 12- and 24-month overall survival rates were 97.6% (95% confidence interval: 92.6-99.2) and 86.6% (95% confidence interval: 78.7-91.7), respectively. Rate of pneumothorax that required pleural catheter placement was 26% (44/169). There were eight grade 3 complication events in 169 procedures (4.7%) and one (0.6%) grade 4 event. CONCLUSION: Percutaneous cryoablation is a safe and effective treatment for pulmonary metastases.