Does restricted diffusion in the splenium indicate an acute infarct?

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Splenium lesions are uncommon but associated with diverse conditions including ischemic infarcts, drug toxicity, encephalitis, and metabolic disturbances.
• Accurate diagnosis of splenium lesions is critical due to their varied underlying pathologies.

Purpose of the Study:

• To evaluate the clinical and imaging findings and determine the etiologies of splenium lesions in a cohort of 16 patients.

Main Methods:

• Retrospective analysis of 16 patients with splenium lesions between 2013 and 2017.
• Magnetic resonance imaging (MRI) including fluid attenuation inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) mapping was performed.

Main Results:

• The study included 11 males and 5 females (mean age 52.3 years) presenting with symptoms like consciousness disorder, headache, seizure, and hemiparesis.
• MRI revealed splenium hyperintensity on DWI in all patients, with 87.5% showing hypointensity on ADC.
• Identified etiologies included ischemic infarction (25%), tuberculous meningitis (18.7%), viral encephalitis (12.5%), and other less common causes.

Conclusions:

• Diffuse restriction on MRI, particularly in the splenium, does not always indicate ischemic stroke.
• Splenium lesions can result from various pathologies, necessitating a broad differential diagnosis beyond ischemic infarction.
• Comprehensive evaluation of clinical symptoms and potential etiologies is essential for managing patients with splenium lesions.