Facial surface symmetry, which is poorly assessed subjectively, can be easily and reproducibly measured using three-dimensional photogrammetry. The RMSD for facial asymmetry of healthy volunteers clusters at approximately 0.80 ± 0.24 mm. Patients with facial asymmetry due to a pathologic process can be differentiated from normative facial asymmetry based on their RMSDs.

Background: Facial symmetry is a fundamental goal of plastic surgery, yet some asymmetry is inherent in any face. Three-dimensional photogrammetry allows for rapid, reproducible, and quantitative facial measurements. With this tool, the authors investigated the relationship between age and facial symmetry. Methods: The authors imaged normal subjects using three-dimensional photogrammetry. Facial symmetry was calculated by identifying the plane of maximum symmetry and the root-mean-square deviation. Regression analysis was used to assess the relationship between age and symmetry. Subgroup analyses were performed among facial thirds. Results: The authors imaged 191 volunteers with an average age of 26.7 ± 22.2 years (range, 0.3 to 88 years). Root-mean-square deviation of facial symmetry clustered between 0.4 and 1.3 mm (mean, 0.8 ± 0.2 mm). The authors found a significant positive correlation between increasing age and asymmetry (p < 0.001; r = 0.66). The upper, middle, and lower facial third’s average root-mean-square deviations were 0.5 ± 0.2 mm (range, 0.2 to 1.2 mm), 0.6 ± 0.2 mm (range, 0.2 to 1.4 mm), and 0.6 ± 0.2 mm (range, 0.2 to 1.2 mm), respectively. Asymmetry also increased with age across all facial thirds (p < 0.001). Conclusions: Facial asymmetry increases with age in each facial third, with a greater asymmetry and increase in asymmetry in the lower two-thirds. Contributing factors may include asymmetric skeletal remodeling along with differential deflation and descent of the soft tissues. The observed correlation between increasing facial asymmetry and age may be a useful guide in plastic surgery to produce age-matched features.

Preoperative metopic forehead contours varied significantly from postoperative contours. Cranial reconstructions approximated the foreheads of normal controls, and reconstructions were stable at more than 1-year follow-up.

Three-dimensional photogrammetry was used to successfully compare symmetry among different patient and control groups. Although "normal" nasal symmetry was attained in some patients following cleft lip/nasal repair, most had persistent asymmetry compared with normal controls. Placement of a resorbable internal splint did not improve symmetry in patients with unilateral complete cleft lip/palate.

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Background: Craniosynostosis is typically diagnosed postnatally. Prenatal diagnosis would allow for improved parental counseling and facilitate timely intervention. Our purpose was to determine whether prenatal ultrasound can be used to diagnose nonsyndromic craniosynostosis. Methods: The authors reviewed 22 prenatal ultrasounds of infants known to have nonsyndromic craniosynostosis and 22 age-matched controls. Cross-sectional images at the plane used to measure biparietal diameter were selected and cranial shape of each participant was parameterized and used to discriminate affected patients from controls. The results from quantitative shape analysis were compared with results from a blinded visual inspection alone. Results: Among the 22 patients, the most common diagnosis was sagittal synostosis (n = 11), followed by metopic synostosis (n = 6). The average gestational age at time of ultrasound of controls and synostotic patients was 26 weeks and 6.8 days at the junction of the second and third trimesters. The controls and synostotic cases segregated into statistically different populations by their shape profiles (p < 0.001). An automatic shape classifier using leave-one-out cross-validation correctly classified the 44 images as normal versus synostotic 85 percent of the time (sensitivity, 82 percent; specificity, 87 percent). Cephalic index was a poor indicator of sagittal synostosis (45 percent sensitivity). Visual inspection alone demonstrated only a fair level of accuracy (40 to 50 percent agreement) in identifying cases of synostosis (kappa, 0.09 to 0.23). Conclusions: Craniosynostosis can be identified on prenatal ultrasound with good sensitivity using formal shape analysis. Cephalic index and visual inspection alone performed poorly. CLINICAL QUESTION/LEVEL OF EVIDENCE: Diagnostic, II.

Objective: To assess whether children with torticollis have quantifiably greater facial asymmetry than their age-matched controls using 3-dimensional (3D) photogrammetry. Design: We retrospectively analyzed patients diagnosed with torticollis and age-matched volunteers who underwent 3D photogrammetry of their faces. We calculated the root mean square deviation (RMSD) between native and reflected facial images, as a measure of asymmetry. Two observers independently measured RMSD values for all study participants. The Spearman correlation coefficient evaluated interobserver reliability. The Wilcoxon rank-sum test with Bonferroni adjusted P values for multiple comparisons. Setting: Institutional. Participants: Twenty patients diagnosed with torticollis and 12 age-matched volunteers. Patients were analyzed on a computer database and volunteers were selected and consented in the hospital. We excluded patients with a history of facial trauma, facial operations, or other craniofacial diagnoses. Interventions: Facial surface scans were obtained using the Canfield Vectra stereophotogrammetry system. The technology captures surface anatomy without radiation. Main Outcome Measures: RMSD comparisons between patients with torticollis and age-matched controls. Results: Compared to controls, patients with torticollis had statistically significant greater full face, upper third, and middle third facial asymmetry. There was a trend toward greater asymmetry of the lower facial third. Conclusions: We used 3D photogrammetry to quantitate facial asymmetry from torticollis. We found greater asymmetry in patients with torticollis than in their unaffected peers. All areas of the face appeared to be affected, though the asymmetry in the lower facial third just failed to reach significance.

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