A novel online education module to teach clinicians how to correctly identify ultrasonographic features of mediastinal lymph nodes during endobronchial ultrasound

Preoperative mediastinal staging in early-stage lung cancer: Targeted nodal sampling is not inferior to systematic nodal sampling

OBJECTIVE

To determine whether targeted sampling (TS), which omits biopsy of triple- normal lymph nodes (LNs) on positron emission tomography, computed tomography, and endobronchial ultrasound (EBUS), is noninferior to systematic sampling (SS) of mediastinal LNs during EBUS for staging of patients with early-stage non-small cell lung cancer (NSCLC).

METHODS

Patients who are clinical nodal (cN)0-N1 with suspected NSCLC eligible for EBUS based on positron emission tomography/computed tomography were enrolled in this prospective, multicenter trial. During EBUS, all patients underwent TS and then crossed over to SS, whereby at least 3 mediastinal LN stations (4R, 4L, 7) were routinely sampled. Gold standard of comparison was pathologic results. Based on the previous feasibility trial, a noninferiority margin of 6% was established for difference in missed nodal metastasis (MNM) incidence between TS and SS. The McNemar test on paired proportions was used to determine MNM incidence for each sampling method. Analysis was per-protocol using a level of significance of P < .05.

RESULTS

Between November 2020 and April 2022, 91 patients were enrolled at 6 high-volume Canadian tertiary care centers. A total of 256 LNs underwent TS and SS. Incidence of MNM was 0.78% in SS and 2.34% in TS, with an absolute difference of 1.56% (95% confidence interval, -0.003% to 4.1%; P = .13). This falls within the noninferiority margin. A total of 6/256 LNs from 4 patients who were not sampled by TS were found to be malignant when sampled by SS.

CONCLUSIONS

In high-volume thoracic endosonography centers, TS is not inferior to SS in nodal staging of early-stage NSCLC. This results in change of clinical management for a minority of patients.

Comparing the Effectiveness and Image Quality of Musculoskeletal Ultrasound of First-Year Medical Students After Training by Student Tutors Versus Ultrasound Instructors: A Pilot Study

Background

Ultrasound is a vital part in many medical schools’ curriculum. Although there is strong support for the use of student tutors (STs), there is a lack in gauging their effectiveness with more difficult organ systems such as the musculoskeletal (MSK) system. We aim to determine the effectiveness of using STs versus expert ultrasound instructors (UIs) when teaching MSK ultrasound.

Methodology

Medical students were recruited to participate in an MSK workshop to identify superficial volar arm structures (radial nerve, radial artery, median nerve, ulnar artery, ulnar nerve) using Butterfly iQ. In total, 14 participants were taught by STs and 10 participants were taught by UIs. Participants imaged the five structures and answered surveys gauging their confidence via five-point Likert scales.

Results

There was no significant difference in confidence or identification accuracy for all five structures between the two groups. However, there was a significant difference in confidence in the understanding of basic ultrasound concepts in favor of the UI group (p < 0.05). A greater number of students were more confident in identifying all five structures when taught by STs, but more students correctly identified the structures when taught by UIs.

Conclusions

The results on confidence could be due to positive peer perception. Both groups scored relatively high in their identification accuracies, promoting the successful use of STs. The successful use of STs in teaching MSK ultrasound opens the possibility to developing peer-led ultrasound curriculum on more complex ultrasound topics in the future.

Clinical Validation of the Canada Lymph Node Score for Endobronchial Ultrasound

BACKGROUND

The Canada Lymph Node Score (CLNS) uses four sonographic criteria to predict the risk of malignancy in lymph nodes during endobronchial ultrasound (EBUS). CLNS may play a role in identifying targets for biopsy or re-biopsy during invasive mediastinal staging for lung cancer. However, CLNS has not yet been prospectively validated in routine clinical practice.

METHODS

CLNS scores for each lymph node biopsied during EBUS were prospectively captured for one year (2019). CLNS and the presence of malignancy in each node were compared. Univariate binary logistic regression was completed for each ultrasonographic feature, as well as a multivariate logistic regression model.

RESULTS

CLNS and diagnostic pathology results were available for 367 lymph nodes. Incidence of malignancy increased with higher scores. Scores ≥3 were significantly associated with malignancy (specificity 84.4%, positive likelihood ratio 4.0). Area under the curve was 0.76, indicating a good ability of the model to predict presence or absence of malignancy. Nodes scoring <2 and negative on CT and PET were malignant in 10.1%.

CONCLUSIONS

CLNS correlates with the presence or absence of malignancy in thoracic lymph nodes, and may serve as an adjunct to currently available methods of invasive and non-invasive mediastinal staging. CLNS may be most helpful to select which non-diagnostic nodes require re-biopsy. There is a significant risk of a false negative result even with a score of 0, and using a combination of low CLNS and negative conventional radiology to obviate the need for any initial biopsy remains to be studied in prospective trials.

Can ultrasound novices develop image acquisition skills after reviewing online ultrasound modules?

BACKGROUND

Point-of-care ultrasound is becoming a ubiquitous diagnostic tool, and there has been increasing interest to teach novice practitioners. One of the challenges is the scarcity of qualified instructors, and with COVID-19, another challenge is the difficulty with social distancing between learners and educators. The purpose of our study was to determine if ultrasound-naïve operators can learn ultrasound techniques and develop the psychomotor skills to acquire ultrasound images after reviewing SonoSim® online modules.

METHODS

This was a prospective study evaluating first-year medical students. Medical students were asked to complete four SonoSim® online modules (aorta/IVC, cardiac, renal, and superficial). They were subsequently asked to perform ultrasound examinations on standardized patients utilizing the learned techniques/skills in the online modules. Emergency Ultrasound-trained physicians evaluated medical students' sonographic skills in image acquisition quality, image acquisition difficulty, and overall performance. Data are presented as means and percentages with standard deviation. All P values are based on 2-tailed tests of significance.

RESULTS

Total of 44 medical students participated in the study. All (100%) students completed the hands-on skills evaluation with a median score of 83.7% (IQR 76.7-88.4%). Thirty-three medical students completed all the online modules and quizzes with median score of 87.5% (IQR 83.8-91.3%). There was a positive association between module quiz performance and the hands-on skills performance (R-squared = 0.45; p < 0.001). There was no statistically significant association between module performance and hands-on performance for any of the four categories individually. In all four categories, the evaluators' observation of the medical students' difficulty obtaining views correlated with hands-on performance scores.

CONCLUSIONS

Our study findings suggest that ultrasound-naïve medical students can develop basic hands-on skills in image acquisition after reviewing online modules.