Alteration of fractional anisotropy and apparent diffusion coefficient in obsessive-compulsive disorder: a diffusion...

Area of Science:

• Neuroimaging
• Neuroscience
• Psychiatry

Background:

• Previous diffusion tensor imaging (DTI) studies in obsessive-compulsive disorder (OCD) reported inconsistent fractional anisotropy (FA) findings.
• The apparent diffusion coefficient (ADC) in OCD has not been extensively studied.

Purpose of the Study:

• To investigate white matter abnormalities using FA and water diffusivity using ADC in OCD patients via DTI.
• To compare FA and ADC values between OCD patients and healthy controls.

Main Methods:

• Diffusion tensor imaging (DTI) was performed on 15 patients with OCD and 15 healthy volunteers.
• Voxelwise analysis was employed to compare FA in white matter and ADC in gray and white matter between the groups.

Main Results:

• Patients with OCD exhibited higher FA in the bilateral semioval center and subinsular white matter compared to controls.
• A higher ADC was observed in the left medial frontal cortex of OCD patients.
• No significant reductions in FA or ADC were found in OCD patients relative to healthy volunteers.

Conclusions:

• Elevated FA in disgust-processing regions suggests their potential role in OCD pathophysiology.
• A trend for higher ADC in emotion-regulation areas hints at altered water diffusivity in these circuits.
• These DTI findings highlight the involvement of specific neurocircuits in the development of OCD.