Clinical implications of splenium magnetic resonance imaging signal changes.

BACKGROUND Magnetic resonance imaging (MRI) may show discrete splenium abnormalities; however, the implications of this radiologic finding are unclear. OBJECTIVE To describe causes, clinical presentations, and prognoses of midline splenium changes evident on MRI. DESIGN Retrospective case series. SETTING Teaching hospital. PATIENTS Medical records of 9 patients with MRI-noted splenium changes were studied; 60 additional published cases were accessed. INTERVENTIONS Sixty-nine cases were reviewed. MAIN OUTCOME MEASURES Clinical and imaging findings, causes, and prognosis. RESULTS Confusion (35 patients), ataxia (25 patients), and recent seizure (23 patients) were common. Causes included alcohol use, infections, hypoglycemia, trauma, salt abnormalities, and seizure. Twenty-eight patients had complete resolution, 23 improved, and 1 died. Diffusion-weighted imaging showed splenium abnormalities the best. Eleven of 12 patients showed decrease in apparent diffusion coefficient. Most improved clinically, as did their subsequent MRI studies. CONCLUSIONS Midline splenium changes are commonly seen on MRI diffusion-weighted imaging sequences. Multiple causes can result in splenium changes. Physicians should evaluate for glucose and electrolyte abnormalities, seizure risk, ongoing infectious or parainfectious process, and traumatic causes.