Comparing the Accuracy and Reliability of ABC/2 and Planimetry for Vestibular Schwannoma Volume Assessment.

Background: Vestibular schwannoma (VS) is a common intracranial tumor that affects patients' quality of life. Reliable imaging techniques for tumor volume assessment are essential for guiding management decisions. The study aimed to compare the ABC/2 method to the gold standard planimetry method for volumetric assessment of VS.

Methods: A retrospective review was conducted on patients with VS diagnosed between 2007 and 2022 at Yale New Haven Hospital. Both ABC/2 and planimetry methods were used for tumor volume assessment, and their correlations were evaluated.

Results: Among 140 patients, the mean tumor volumes using the planimetry and ABC/2 methods were 1307.99 ± 142.13 and 1482.76 ± 165.75 mm3, respectively. A strong correlation was observed between the methods (r = 0.99, p < 0.0001). For patients who underwent follow-up scans, the ABC/2 method accurately detected tumor volume changes over time. Subgroup analysis based on tumor size also displayed a significant positive correlation across all size categories.

Conclusion: The ABC/2 method demonstrates a high correlation with the planimetry method for VS volume assessment and can be a reliable, less time-intensive alternative in clinical settings. However, it generally overestimates tumor volume compared to planimetry. Subgroup-specific correction formulae were provided to enhance the accuracy of ABC/2-derived measurements. Future studies may explore the integration of these methods for improved clinical decision making.