Damage to the right superior longitudinal fasciculus in the inferior parietal lobe plays a role in spatial neglect

Functional neurological changes after surgery combined with data from diffusion tensor imaging (DTI) studies can provide direct evidence of anatomical localization of brain function. The goal of the present study was to characterize mechanisms of spatial neglect using these techniques by analyzing two patients with development or worsening of left neglect after surgery at our hospital in 2008. In both cases, the surgical approach was via the right inferior parietal lobes, and damage to the superior longitudinal fasciculus (SLF) was demonstrated after surgery by DTI tractography. By contrast, neither the inferior longitudinal fasciculus (ILF) nor the inferior fronto-occipital fasciculus (IFOF) was damaged. These results suggest that damage to the right SLF in the inferior parietal lobe plays a critical role in the development of spatial neglect.