Pure visuospatial neglect due to cingulum bundle disconnection in right anterior cerebral artery infarction: a case report with diffusion tensor imaging analysis

Visuospatial neglect is a common finding associated with lesions in the middle and posterior cerebral artery territories, with a higher incidence in right hemispheric infarctions. In anterior cerebral artery (ACA) infarction, neglect is typically accompanied by motor deficits or manifests as motor neglect. Pure visuospatial neglect without motor involvement in the setting of ACA infarction therefore represents an uncommon clinical presentation. A 62-year-old woman presented with a cognitive decline, including perseverative behavior and disorientation to time. Brain magnetic resonance imaging (MRI) revealed a right medial frontal acute infarction. Neurological examination revealed intact motor function. However, bedside tests and the Seoul Neuropsychological Screening Battery (SNSB) demonstrated severe left-sided visuospatial neglect with domain-specific dissociation: visuospatial attention was severely impaired while verbal attention remained preserved. Diffusion tensor imaging (DTI) tractography revealed severe and preferential disruption of the right cingulum bundle (78% reduction in tract count; asymmetry ratio 0.22) with relative preservation of the superior longitudinal fasciculus (31.8% reduction in tract count) and intact parietal aslant tract. This case demonstrates that motor-sparing ACA infarction can produce severe pure visuospatial neglect, and highlights the importance of careful neuropsychological evaluation and active rehabilitation even in the absence of motor weakness.