Optical coherence tomography findings in conversion disorder: are there any differences in the etiopathogenesis of subtypes?

Background: Optical coherence tomography is a contactless and fast neuroimaging method. Previous Studies have observed thinning of the ganglion cell layer and inner plexiform layer in many neurodegenerative diseases. Objective: The aim of this study was to compare the layers of ganglion cell complex in conversion disorder. Methods: This study involved 50 conversion disorder patients and 50 healthy volunteers as the control. The parameters were measured and recorded automatically by a spectral optical coherence tomography device. Results: There was no difference in the retinal nerve fiber layers between the conversion disorder group and the control group (p > 0.05). The left and right choroid layer thickness acquired from three regions of the choroid layer was higher in patients compared with controls (p < 0.05). The ganglion cell layer and inner plexiform layer volumes were also significantly lower in the patient group (p < 0.05). Discussion: These ganglion cell layer and inner plexiform layer findings suggest that neurodegeneration occurs during the course of conversion disorder especially in subtype involved motor component. The choroid seems to be more related to the sensory component and it may be used to determine the active stage of the disease and to monitor inflammatory process like other inflammation markers used in systemic inflammatory diseases.