Modeling diffusion-weighted imaging lesion expansion between 2 and 24 h after endovascular thrombectomy in acute ischemic stroke

PURPOSE

Diffusion-weighted imaging (DWI) lesion expansion after endovascular thrombectomy (EVT) is not well characterized. We used serial diffusion-weighted magnetic resonance imaging (MRI) to measure lesion expansion between 2 and 24 h after EVT.

METHODS

In this single-center observational analysis of patients with acute ischemic stroke due to large vessel occlusion, DWI was performed post-EVT (< 2 h after closure) and 24-h later. DWI lesion expansion was evaluated using multivariate generalized linear mixed modeling with various clinical moderators.

RESULTS

We included 151 patients, of which 133 (88%) had DWI lesion expansion, defined as a positive change in lesion volume between 2 and 24 h. In an unadjusted analysis, median baseline DWI lesion volume immediately post-EVT was 15.0 mL (IQR: 6.6-36.8) and median DWI lesion volume 24 h post-EVT was 20.8 mL (IQR: 9.4-66.6), representing a median change of 6.1 mL (IQR: 1.5-17.7), or a 39% increase. There were no significant associations among univariable models of lesion expansion. Adjusted models of DWI lesion expansion demonstrated that relative lesion expansion (defined as final/initial DWI lesion volume) was consistent across eTICI scores (0-2a, 0.52%; 2b, 0.49%; 2c-3, 0.42%, p = 0.69). For every 1 mL increase in lesion volume, there was 2% odds of an increase in 90-day mRS (OR: 1.021, 95%CI [1.009, 1.034], p < 0.001).

CONCLUSION

We observed substantial lesion expansion post-EVT whereby relative lesion expansion was consistent across eTICI categories, and greater absolute lesion expansion was associated with worse clinical outcome. Our findings suggest that alternate endpoints for cerebroprotectant trials may be feasible.

Prospective Margin Estimates Predict Local Tumor Progression Following Microwave Ablation of Small Renal Masses

PURPOSE

To evaluate the relationship between prospectively generated ablative margin estimates and local tumor progression (LTP) among patients undergoing microwave ablation (MWA) of small renal masses (SRMs).

MATERIALS AND METHODS

Between 2017 and 2020, patients who underwent MWA for SRM were retrospectively identified. During each procedure, segmented kidney and tumor shapes were coregistered with intraprocedural helical CT images obtained after microwave antenna placement. Predicted ablation zone shape and size were then overlaid onto the resultant model, and a model-to-model distance algorithm was employed to calculate multiple ablative margin estimates. LTP was modeled as a function of each margin estimate by hazard regression. Models were evaluated using hazard ratios and Akaike information criterion. Receiver operating characteristic curve area under the curve was also estimated using Harrell's and Uno's C indices (HI and UI, respectively).

RESULTS

One hundred and twenty-eight patients were evaluated (median age 72.1 years). Mean tumor diameter was 2.4 ± 0.9 cm. LTP was observed in nine (7%) patients. Analysis showed that decreased estimated margin size as measured by first quartile (Q1; 25th percentile), maximum, and average ablative margin metrics was significantly associated with risk of LTP. For every one millimeter increase in Q1, maximum, and mean ablative margin, the hazard of LTP increased 67% (HR: 1.67; 95% CI = 1.25-2.20, UI = 0.93, HI = 0.77), 32% (HR: 1.32; 95% CI 1.09-1.60; UI = 0.93; HI = 0.76), and 48% (HR: 1.48; 95% CI 1.18-1.85; UI = 0.83; HI = 0.75), respectively.

CONCLUSION

Prospectively generated ablative margin estimates can be used to predict the risk of local tumor progression following microwave ablation of small renal masses. LEVEL OF EVIDENCE 3: Retrospective cohort study.

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.

Long-term effect of field triage on times to endovascular treatment for emergent large vessel occlusion

BACKGROUND

Delays to endovascular therapy (EVT) for stroke may be mitigated with direct field triage to EVT centers. We sought to compare times to treatment over a 5.5 year span between two adjacent states, one with field triage and one without, served by a single comprehensive stroke center (CSC).

METHODS

During the study period, one of the two states implemented severity-based triage for suspected emergent large vessel occlusion, while in the other state, patients were transported to the closest hospital regardless of severity. We compared times to treatment and clinical outcomes between these two states. We also performed a matched pairs analysis, matching on date treated and distance from field to CSC.

RESULTS

639 patients met the inclusion criteria, 407 in State 1 (with field triage) and 232 in State 2 (without field triage). In State 1, scene to EVT decreased 6% (or 8.13 min, p=0.0004) every year but no decrease was observed for State 2 (<1%, p=0.94). Cumulatively over 5.5 years, there was a reduction of 43 min in time to EVT in State 1, but no change in State 2. Lower rates of disability were seen in State 1, both for the entire cohort (all OR 1.22, 95% CI 1.07 to 1.40, p=0.0032) and for those independent at baseline (1.36, 95% CI 1.15 to 1.59, p=0.0003).

CONCLUSIONS

Comparing adjacent states over time, the implementation of severity-based field triage significantly reduced time to EVT.

The Impact of Emerging Technologies on Residency Selection by Medical Students in 2017 and 2021, With a Focus on Diagnostic Radiology

RATIONALE AND OBJECTIVES

We sought to determine the perceived impact of artificial intelligence (AI) and other emerging technologies (ET) on various specialties by medical students in both 2017 and 2021 and how this might affect their residency selections.

MATERIALS AND METHODS

We conducted a brief, anonymous survey of all medical students at a single institution in 2017 and 2021. Survey questions evaluated (1) incentives motivating residency selection and career path, (2) degree of interest in each specialty, (3) perceived effect that ET will have on job prospects for each specialty, and (4) those specialties that students would not consider because of concerns regarding ET.

RESULTS

A total of 72% (384/532) and 54% (321/598) of medical students participated in the survey in 2017 and 2021, respectively, and results were largely stable. Students perceived ET would reduce job prospects for pathology, diagnostic radiology, and anesthesiology, and enhance prospects for all other specialties (p < 0.01) except dermatology. For both surveys, 23% of students would NOT consider diagnostic radiology because ET would make it obsolete, higher than all other specialties (p < 0.01). Regarding the one student class that was surveyed twice, 50% felt ET would reduce job prospects for radiology in 2017, increasing to 71% in 2021 (p < 0.01), and similar percentages-20% in 2017 and 23% in 2021-said they explicitly would not consider radiology because of concerns levied by ET.

CONCLUSIONS

Current perceptions of ET likely affect residency selection for a large proportion of medical students and may impact the future of various specialties, particularly diagnostic radiology.

A pilot study of accelerometer-based biometric data collection among patients undergoing locoregional therapies

This study evaluated the feasibility of measuring patient recovery following locoregional therapies (LRT) using a wearable activity tracker (WAT). Twenty adult cancer patients were provided with a WAT device to wear for a minimum of seven days prior to their procedure (baseline) and for up to 30 days after their procedure (recovery). Daily step counts were continuously recorded. Patient responses to the SF-36 Health Survey were also collected before and following LRT. Analysis of WAT data demonstrated a mean of 4850 daily steps taken at baseline, which decreased to 2000 immediately following LRT then rapidly increased to approximately 4300 daily steps over an average of 10 days (p<0.001). No significant changes were observed in SF-36 responses between baseline and follow-up assessments (p>0.10). These results suggest that WAT devices capture dynamic peri-procedural data not reflected in survey-based assessments and may be used to monitor patient recovery following interventional oncology procedures.

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.