Lesions in the splenium of the corpus callosum: Clinical and radiological implications

Abstract

Background: Brain MRI may unexpectedly display abnormalities in splenium of the corpus callosum (SCC). However, the clinical implications of this lesion are unclear and are not always consistent with ischemic infarctions. We performed this study to clarify the clinical and radiological implications in patients with SCC lesions. Methods: We retrospectively reviewed consecutive patients with MRI-reported SCC changes between 2009 and 2012. We analyzed clinical and radiological findings, etiologies, cognitive impairment, and clinical outcomes. Results: We found 30 patients (16 females; mean 50.5 years) who had SCC lesions on MRI. Confusion was the most common clinical finding in 50% of cases. Cerebral infarction was the most common etiology (50%). The most consistent SCC changes on MRI were low signal in T1WI, high signal on T2WI and FLAIR, and high signal on DWI. We classified SCC lesions into in situ SCC lesions (SCC only) and multiple (SCC plus) lesions for patients with multiple lesions. The clinical symptoms of SCC only lesions were relatively mild. Cognitive functions were evaluated by Mini Mental State Examination (MMSE) and clinical dementia rating (CDR) scale at the time of discharge and patients with SCC only lesions showed less impaired cognition compared with those with SCC plus lesions. Clinical outcomes were evaluated by the modified Rankin scale at 1 month and patients with SCC only lesions revealed good clinical outcomes compared with those with SCC plus lesions. Conclusions: MRI-reported SCC lesions may have heterogeneous etiologies and present with various symptoms. The clinical course and outcome are relatively good, particularly in small isolated and oval shaped SCC lesions.