Fig. 2

Detailed workflow for the calculation of HII. DICOM images data were transferred to 3D Slicer, and hematomas were semi-automatically identified pixel by pixel in each slice with PaintEffect in Editor module. The Models module in the software was utilized to reconstruct a three-dimensional data by adding up volume of all the pixels, and data on the volumes and surface area were directly obtained from the software. The hematoma irregularity index was defined as  \(\sqrt{\frac{\mathrm S/\mathrm\pi}2}/\sqrt[3]{3V/4\mathrm\pi}{}^\ast100\). The time required for the entire process was recorded. S, surface area; V, volume; HII, hematoma irregularity index