Measurement of Orbital Volume from Facial CT Scans Using a Semi-Automatic Computer Program

Abstract

Purpose: To measure the orbital volume from facial CT scans using a semi-automatic computer program. Methods: Axial and coronal slices of 35 facial CT scans were used to measure the orbital volume. The cross-sectional area was determined from each slice using a semi-automated computer program (MATLAB 2009a). Next, the orbital volume was calculated from serial reconstruction of the cross-sections. Results: The measured value in males was 26.34 ± 3.09 cm in the right orbit and 26.30 ± 3.21 cm in the left orbit from axial scans, and 26.58 ± 2.76 cm in the right orbit and 26.59 ± 2.75 cm in the left orbit from coronal scans. In females, the values were 23.84 ± 2.29 cm in the right orbit and 23.89 ± 2.33 cm in the left orbit from axial scans, and 24.06 ± 2.90 cm in the right orbit and 24.10 ± 2.82 cm in the left orbit from coronal scans. There was high positive correlation (r = +0.832, p = 0.0001) in measured orbital volume between axial and coronal scans. Conclusions: The orbital volume measurement from facial CT scans using a semi-automatic computer program is very useful. This method should prove useful in further studies examining the correlation of orbital volume variation in many ophthalmologic disorders. J Korean Ophthalmol Soc 2015;56(2):168-173