Quantitative analysis of brainstem atrophy on magnetic resonance imaging in chronic progressive neuro-Behçet's...

To examine whether quantitative analysis of the brainstem areas on magnetic resonance imaging (MRI) scans is useful for diagnosis as well as evaluation of disease activity in chronic progressive neuro-Behçet's disease (CPNB).

MRI scans in patients with acute neuro-Behçet's disease (ANB) (n = 10), CPNB (n = 10), Behçet's disease with neurological manifestations non-attributable to NB (non-NB) (n = 8), and control patients with non-inflammatory neurological diseases (NID) (n = 10) were studied. The areas of midbrain tegmentum and pons were measured on mid-sagittal sections of T1-weighted images of MRI using software NIH Image J ver.1.45.

The areas of midbrain tegmentum as well as those of pons were significantly decreased in CPNB compared with those in the other three groups. On receiver operating characteristic (ROC) analysis, the sensitivity and specificity of the areas of brainstem combining midbrain tegmentum and pons for diagnosis of CPNB against non-CPNB (ANB+non-NB) were 80.0% and 94.4%, respectively, at cut-off value of 614.9 mm(2). Brainstem atrophy progressed most markedly during the first 2 years during the course of CPNB. Moreover, the progression rate of atrophy was closely correlated with the elevation of cerebrospinal fluid interleukin-6.

These results indicate that quantitative analysis of the brainstem areas on MRI scans is effective for diagnosis as well as for evaluation of the disease activity in CPNB. Moreover, it is suggested that an appropriate therapeutic intervention to reduce CSF IL-6 would be required as early as possible upon diagnosis of CPNB.