Comparison of Intracerebral Hemorrhage Volume Calculation Methods and Their Impact on Scoring Tools.
Intracerebral hemorrhage (ICH) volumes are frequently used for prognostication and inclusion of patients in clinical trials. We sought to compare the original ABC/2 method and sABC/2, a simplified version with the planimetric method.



We retrospectively reviewed admission head CT scans of consecutive ICH patients admitted to a single academic center from July 2012 to April 2013. We assessed ICH volume on the admission. In ABC/2 method, A = greatest hemorrhage diameter by CT, B = diameter perpendicular to A, C = the approximate number of CT slices with hemorrhage multiplied by the slice thickness. C is weighted by area as < 25%, 25-50%, or > 75%. However, in the sABC/2 method, C is the total number of cuts with ICH without any weighting. Bland-Altman plots were generated for both the ABC/2 and sABC/2 methods in comparison to the planimetric method.



One hundred thirty-five patients with spontaneous ICH were included in the final analysis. Bland-Altman analysis illustrated that both ABC/2 and sABC/2 were concordant with the planimetric method. ABC/2 had more bias than sABC/2 (47% vs. 5%, respectively) with no evidence of a linear trend. For differentiating a volume threshold of 30 mL, ABC/2 was less sensitive but more specific than sABC/2 (P < .0001). Concordance between planimetry, ABC/2, and sABC/2 was high, evidenced by most coefficients exceeding .90.



Simplified ABC/2 (sABC/2) method performs better than ABC/2 in calculating ICH volumes. Moreover, it is better in differentiating a volume threshold of 30 mL. These findings may have implications for outcomes prediction and clinical trials inclusion.
Department of Neurology, Brown University, MI.|Neuroscience Institute (Division of Neurology), Spectrum Health, Michigan State University, MI.
Muhib
M
Khan
Lifespan Biostatistics Core, Lifespan Hospital System, MI.|Department of Diagnostic Imaging, Brown University, MI.
Grayson L
GL
Baird
Department of Neurology, Brown University, MI.
Roderick
R
Elias
The Warren Alpert Medical School, Brown University, MI.
Joshua
J
Rodriguez-Srednicki
Department of Neurology, Brown University, MI.|The Warren Alpert Medical School, Brown University, MI.
Shadi
S
Yaghi
Department of Neurology, Brown University, MI.
Sandra
S
Yan
Department of Diagnostic Imaging, Brown University, MI.
Scott
S
Collins
Department of Neurosurgery, Brown University, MI.
Bradford B
BB
Thompson
Department of Neurology, Brown University, MI.|Department of Neurosurgery, Brown University, MI.|Section of Medical Education, Brown University, MI.
Linda C
LC
Wendell
Department of Neurology, Brown University, MI.|Department of Neurosurgery, Brown University, MI.
Nicholas S
NS
Potter
Department of Neurology, Brown University, MI.|Department of Neurosurgery, Brown University, MI.
Corey
C
Fehnel
Department of Neurology, Brown University, MI.
Ali
A
Saad
Department of Neurology, Brown University, MI.
Brian
B
Silver
D000368:Aged; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging*; D005260:Female; D006406:Hematoma / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
ABC/2; Intracerebral hemorrhage; outcome; planimetry