Retrospective Validation of a Computer-Assisted Quantification Model of Intracerebral Hemorrhage Volume on Accuracy, Precision, and Acquisition Time, Compared with Standard ABC/2 Manual Volume Calculation

• Published in: American journal of neuroradiology : AJNR 2017-08, Vol.38 (8), p.1536-1542
• Main Authors: Xue, W, Vegunta, S, Zwart, C M, Aguilar, M I, Patel, A C, Hoxworth, J M, Demaerschalk, B M, Mitchell, J R
• Format: Article
• Language: English
• Subjects: Adult Brain; Algorithms; Bias; Cerebral Hemorrhage - diagnostic imaging; Cerebral Hemorrhage - pathology; Clinical trials; Computer graphics; Computer Simulation; Hemorrhage; Humans; Medical research; Model accuracy; Patient admissions; Reproducibility of Results; Retrospective Studies; Segmentation; Tomography, X-Ray Computed - methods
• ISSN: 0195-6108; 1936-959X
• DOI: 10.3174/ajnr.A5256

Intracerebral hemorrhage accounts for 6.5%-19.6% of all acute strokes. Initial intracerebral hemorrhage volume and expansion are both independent predictors of clinical outcomes and mortality. Therefore, a rapid, unbiased, and precise measurement of intracerebral hemorrhage volume is a key component of clinical management. The most commonly used method, ABC/2, results in overestimation. We developed an interactive segmentation program, SegTool, using a novel graphic processing unit, level set algorithm. Until now, the speed, bias, and precision of SegTool had not been validated. In a single stroke academic center, 2 vascular neurologists and 2 neuroradiologists independently performed a test-retest experiment that involved repeat measurements of static, unchanging intracerebral hemorrhage volumes on CT from 76 intracerebral hemorrhage cases. Measurements were made with SegTool and ABC/2. True intracerebral hemorrhage volumes were estimated from a consensus of repeat manual tracings by 2 operators. These data allowed us to estimate measurement bias, precision, and speed. The measurements with SegTool were not significantly different from the true intracerebral hemorrhage volumes, while ABC/2 overestimated volume by 45%. The interrater measurement variability with SegTool was 50% less than that with ABC/2. The average measurement times for ABC/2 and SegTool were 35.7 and 44.6 seconds, respectively. SegTool appears to have attributes superior to ABC/2 in terms of accuracy and interrater reliability with a 9-second delay in measurement time (on average); hence, it could be useful in clinical trials and practice.