Statistical shape analysis of corpus callosum in functional neurological disorder

Introduction
Functional neurological disorder (FND) is the presence of neurological symptoms in the absence of a neurological disease. Diseases can cause degenerative changes in brain structures such as the corpus callosum (CC). Studies have shown that abnormalities in the CC are associated with FND symptoms. The aim of this study is to evaluate the CC of patients with statistical shape analysis (SSA) and compare it with that of healthy subjects.

Material and methods
Twenty patients with FND and 20 healthy individuals of similar ages, all females, participated in the study. In mid-sagittal images of each individual, the CC was marked using landmarks. The mean of ‘Procrustes’ points was calculated and shape deformations were evaluated using thin plate spline analysis.

Results
Significant differences in shape were observed in the CC between the two groups, with maximum CC deformation in posterior region markings in those with FND. There was no significant difference between the CC area of patients diagnosed with FND and controls.

Conclusions
Corpus callosum analysis with SSA revealed significant differences between patients and healthy subjects. The study findings highlighted the abnormal distribution of white matter in the CC and the variable subregional nature of CC in FND patients. This study may help future studies in terms of FND etiology, diagnosis and treatment options.