Abstract: Towards Addressing the Lack of Parent-Reported Outcomes about Nonsynostotic Plagiocephaly: The Failure of the Argenta Classification

RESULTS: The study included 18 patients with UCS and 19 controls. The average age at time of scan was 5.7 ± 2.2 months for UCS and 5.7 ± 2.9 months for controls (p=0.988). Overall cranial vault volume did not differ between UCS and controls (p= 0.250). Nearly all angles measured between the synostosed side of UCS and control patients—posterior fossa deflection angle (18.0 ± 5.2 vs. 2.4 ± 2.1, respectively), petrous ridge angle (104.0 ± 5.7 vs. 126.6 ± 4.9, respectively), external acoustic meatus angle (92.3 ± 4.8 vs. 100.3 ± 3.4, respectively), articular fossa angle (82.5 ± 3.8 vs. 89.9 ± 4.0, respectively), and bifrontal angle (152.2 ± 6.9 vs. 143.7 ± 8.3, respectively)—were significantly different (p<0.002). Three volumetric ratios comparing the synostosed side to the contralateral were significantly less than controls: anterior (0.44 ± 0.03 vs. 0.5 ± 0.01, p<0.001), middle (0.45 ± 0.02 vs. 0.5 ± 0.02, p<0.001), and posterior (0.46 ± 0.02 vs. 0.50 ± 0.02, p<0.001). The ratio of total middle volume to total cranial volume was larger in UCS patients vs. controls, but the posterior ratio was smaller: anterior (0.13 ± 0.02 vs. 0.12 ± 0.02, p=0.545), middle (0.50 ± 0.05 vs. 0.42 ± 0.04, p=0.001), and posterior (0.37 ± 0.05 vs. 0.45 ± 0.03, p=0.001).