Objective: The authors sought to expand previous findings of vermal abnormalities in bipolar disorder patients.
Method: Magnetic resonance imaging (MRI) morphometry was used to quantify vermal subregion volumes in 18 subjects with first-episode bipolar disorder, 21 subjects with multiple-episode bipolar disorder, and 32 healthy subjects.
Results: Vermal subregion V2 volume was significantly smaller in multiple-episode bipolar disorder subjects than in first-episode patients and healthy subjects. Vermal subregion V3 was significantly smaller in multiple-episode bipolar disorder subjects than in healthy subjects.
Conclusions: These results suggest that posterior-inferior cerebellar vermal abnormalities are present in patients with multiple-episode bipolar disorder.