title: Validation of three-dimensional laser scanning for the assessment of facial fat changes.
abstract: 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.
authors.affiliation: Department of Infectious Diseases, Tan Tock Seng Hospital, Singapore. nick.paton@ctu.mrc.ac.uk
authors.forename: N I
authors.initials: NI
authors.lastname: Paton
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
authors.forename: Y-Y
authors.initials: YY
authors.lastname: Sitoh
authors.forename: Naing Oo
authors.initials: NO
authors.lastname: Tha
mesh_terms: D000328:Adult; D002610:Cheek; D015331:Cohort Studies; D005145:Face; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D019247:HIV Wasting Syndrome / Q000473:pathology; D039682:HIV-Associated Lipodystrophy Syndrome / Q000473:pathology*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007834:Lasers; D008279:Magnetic Resonance Imaging; D008297:Male; D015203:Reproducibility of Results; D016896:Treatment Outcome; D015430:Weight Gain; D015431:Weight Loss