Stereology: a novel technique for rapid assessment of liver volume

BACKGROUND The purpose of this study was to test the stereology method using several grid sizes for measuring liver volume and to find which grid provides an accurate estimate of liver volume. MATERIALS AND METHODS Liver volume was measured by volumetry in 41 sets of liver MRI. MRI was performed before and after different weight-reducing regimens. Grids of 3, 4, 5, and 6 cm were used to measure liver volume on different occasions by stereology. The liver volume and the changes in volume before and after treatment were compared between stereology and volumetry. RESULTS There was no significant difference in measurements between stereology methods and volumetry (p > 0.05). The mean differences in liver volume between stereology based on 3-, 4-, 5-, and 6-cm grids and volumetry were 37, 3, 132, and 23 mL, respectively, and the differences in measurement of liver volume change were 21, 2, 19, and 76 mL, respectively. The mean time required for measurement by stereology was 59-190 s. CONCLUSION Stereology employing 3- and 4-cm grids can rapidly provide accurate results for measuring liver volume and changes in liver volume. MAIN MESSAGES • Statistical methods can be used for measuring area/volume in radiology. • Measuring liver volume by stereology by 4-cm grids can be done in less than two minutes. • Follow-up of liver volume is highly accurate with stereological methods.