PT  - JOURNAL ARTICLE
AU  - Bathla, Girish
AU  - Mehta, Parv M
AU  - Soni, Neetu
AU  - Johnson, Mathew
AU  - Benson, John C
AU  - Messina, Steven A
AU  - Farnsworth, Paul
AU  - Agarwal, Amit
AU  - Carlson, Matthew L
AU  - Lane, John I
TI  - Evaluation of Vestibular Schwannoma Size Over Time: How Well do the Experts Perform and What can be Improved?
AID  - 10.3174/ajnr.A8614
DP  - 2024 Dec 05
TA  - American Journal of Neuroradiology
PG  - ajnr.A8614
4099  - http://www.ajnr.org/content/early/2024/12/05/ajnr.A8614.short
4100  - http://www.ajnr.org/content/early/2024/12/05/ajnr.A8614.full
AB  - BACKGROUND AND PURPOSE: 2D linear measurements are often used in routine clinical practice during vestibular schwannoma (VS) follow-up, primarily due to wider availability and ease of use. We sought to determine radiologist performance compared to 3D-volumetry, along with the impact of number of linear measurements, slice thickness and tumor volumes on these parameters.MATERIALS AND METHODS: Single center retrospective study with 97 patients (592 MRI studies). Overall agreement, sensitivity, specificity and accuracy estimates and 95% confidence intervals were calculated for the entire cohort, and subgroups based on volumes (<400, 400-800, >800 mm3), slice thickness (≤ 1.5 mm or > 1.5 mm) and number of linear dimensions measured in the radiology report (0-1 or 2-3).RESULTS: There was weak agreement between radiologist inference and VS volumetry (0.45, 95% CI [0.41, 0.53]). Agreement was lower when 0-1 tumor dimension was measured (0.29, 95% CI [0.21, 0.42]), for smaller tumors < 400 mm3 (0.37, 95% CI [0.28, 0.45]), and for thick section imaging > 1.5 mm (0.36, 95% CI [0.25, 0.46]). The reader sensitivity was modest (0.49-0.54), while the accuracy for detecting ≤ ±25% interval change was weak (0.32-0.38). Reader performance trended towards improvement with thin-section imaging, measurement of 2-3 VS dimensions and for larger tumors.CONCLUSIONS: In routine practice, radiologists show poor agreement with volumetric results and sensitivity to detect interval change and overall poor accuracy for volumetric changes ≤ ± 25% in volume. In the absence of volumetric measurements, radiologists need to be more diligent when evaluating for interval changes in VS.