Growth and Symmetry of the Levator Veli Palatini Muscle Within the First Two Years of Life

Objective: To quantify differences in levator veli palatini (LVP) muscle dimensions based on age, sex, and race and determine the typical range of asymmetry between the left and right sides of the LVP under age 2 Design: Retrospective cohort study Setting: Children's tertiary care hospital Participants: A retrospective chart review of non-cleft patients under 2 who received a volumetric FLAIR MRI sequence within the past 18 months identified 216 patient scans. Exclusion criteria left 200 scans for analysis. Measurements of the LVP were obtained consistent with previous literature. Interventions: Corrected age, sex, and race Main Outcome Measure(s): LVP muscle dimensions Results: A significant (P <.0001) difference between corrected age groups based on the overall combination of LVP variables after controlling for sex and race. Significant age differences included average extravelar length (P <.0001), average intravelar length (P <.0001), midline thickness (P <.0001), and average (P <.0001) and difference (P =.0413) in insertion thickness. Significant sex differences included average intravelar length (P =.0412) and average insertion thickness (P =.0281). Significant race differences included average insertion thickness (P =.0334) and difference in intravelar length (P =.0473). Differences between left and right total length (P =.0491) and angle of origin (P <.0001) were significant. Conclusions: Differences in LVP morphology were observed in individuals under 2 years or age related to age, sex, and race. While asymmetry was significant in some dimensions, it varied by age range.