Validation of three-dimensional laser scanning for the assessment of facial fat changes

Objective We aimed to evaluate the accuracy of three-dimensional laser scanning as an objective method for detecting facial changes. Methods Facial laser scanning was performed at baseline and repeated after a median of 10 months in 24 HIV-infected patients, 12 with ongoing lipodystrophy, five with > 10% weight loss and seven with > 10% weight gain. Surface volume change was estimated using a standardized technique, and compared with change in cheek fat measured by magnetic resonance imaging (MRI). Results The median laser scanning surface volume changes were -2.1 (range -4.6 to -0.8) mL in the lipoatrophy group, -1.5 (range -6.8 to -1.3) mL in the weight loss group and +3.1 (range -0.2 to +5.4) mL in the weight gain group (the median MRI cheek fat changes were -4.6, -3.7 and +7.0 mL in the three groups, respectively). Laser scanning and MRI measurements were not significantly associated in lipoatrophy patients (r=0.34, P=0.28), but there was a good association in patients who changed weight (r=0.71, P=0.01). Conclusions Laser scanning detects changes in the appropriate direction, although it underestimates MRI-measured cheek fat changes. Laser scanning may be useful as an objective measure of cheek surface volume changes, but needs further validation in larger clinical cohorts.