Global aphasia without hemiparesis: lesion analysis and its mechanism in 11 Korean patients

Abstract

Background: Global aphasia without hemiparesis (GAWH) is a rare stroke syndrome. This study localized the lesion and examined the pathogenic mechanism in Korean patients with GAWH, and investigated whether areas of extensive hypoperfusion existed outside the diffusion-weighted imaging (DWI) lesions seen in these patients. Material and methods: Eleven patients were diagnosed with aphasia using the Western Aphasia Battery. To identify decreased perfusion, which might be functionally relevant to aphasia but not detected by DWI, single photon emission tomography (SPECT) was performed in five patients. To uncover the possible pathogenic mechanisms of ischemic stroke, vascular and cardiologic work-ups were performed in all of the patients. Results: The lesions seen on DWI varied, and included both inferior frontal and superior temporal (three), isolated inferior frontal (four) or superior temporal (one), subcortical (two), and even parieto-occipital (one) lesions. Brain SPECT did not reveal an extensive lesion of the peri-sylvian area outside the DWI lesion in any of the patients, except one with the subcortical lesions. Conclusion: Our results indicate that a single lesion in different locations may be sufficient to produce GAWH, and the lesion profile and stroke mechanism in GAWH are heterogeneous, suggesting that lesions to an area of complex functional anatomy result in aphasia.