Corpus Callosum Shape in Cleft Palate: A Geometric Morphometric Analysis

Objective: Past studies on individuals with isolated orofacial clefts demonstrate the presence of numerous structural brain differences compared to healthy controls.  A recent study of brain shape in individuals with clefts revealed several major differences relating to midline brain structures, including the corpus callosum.  While these midline shape changes were clearly evident in individuals with cleft lip with/without cleft palate (CLP), findings were far more subtle in the isolated cleft palate (CP) group.  The purpose of the present study was to describe the corpus callosum shape phenotype in more detail in a dedicated CP sample.

Method: Midline 2D brain images were obtained from previously collected T1 MRI scans of 10 adult male CP subjects and 40 adult male controls.  All subjects were right-handed.  Eight landmarks on the corpus callosum were collected from each scan and the x.y coordinate locations saved.  A geometric morphometric analysis was performed, involving Procrustes superimposition of the landmark coordinate data followed by discriminant function analysis.

Result: Discriminant analysis revealed no evidence of significant corpus callosum shape differences between CP cases and controls (Mahalanobis distance = 0.5943; p = 0.999).

Conclusion: Building on earlier work, there was little evidence that corpus callosum shape was significantly altered in individuals with isolated cleft palate.  Given the very small sample size, however, it is recommended that these result be viewed as preliminary.