Research paperSubcortical structural volumes in recently remitted first episode mania

- Volume of subcortical structures evaluated in first episode manic subjects.
- No significant difference in volumes between patients and healthy volunteers.
- Subcortical volumetric abnormalities are not apparent in early bipolar disorder.
- Early intervention may arrest neuro-progression in bipolar disorder.

BackgroundMagnetic resonance imaging (MRI) studies have yielded inconsistent findings with regard to subcortical volumetric abnormalities in patients with bipolar I disorder. Duration of illness and long term medication intake could have confounded the findings.MethodVolumes of nine subcortical structures were compared between 63 patients who recently remitted from their first manic episode and 77 healthy volunteers. The volumetric segmentation was performed with the automated segmentation algorithm Freesurfer version 5.1.ResultsThere were no significant volumetric differences between the two groups in any of the structures examined including caudate, putamen, globus pallidum, nucleus accumbens, amygdala, thalamus, cerebellum, hippocampus and lateral ventricles (q > 0.05-false discovery rate corrected).LimitationsAll patients were on psychotropic medications at the time of scanning, which might have confounded the results. Sample size may not be large enough to detect small volumetric changes.ConclusionsPatients with bipolar I disorder do not appear to have any significant subcortical volumetric abnormalities during the early stage of the disease. Thus, early stage bipolar disorder may present an opportunity for intervention to arrest neuroprogression of the disease.