A case of left posterior inferior temporal infarction with right homonymous upper quadrantanopsia and alexia with agraphia for Kanji

Background: Alexia with agraphia usually represents damage in angular gyrus. We report an unusual case of alexia with agraphia caused by a posterior inferior temporal lesion.

Methods: A 82-year-old, right-handed man was admitted because of reading disorder. Visual acuity was 0.7 OD and 0.7 OS. Goldmann perimetry revealed right homonymous upper quadrantanopsia. Standard Language Test of Aphasia revealed mild anomia and severe alexia with agraphia for kanji. Magnetic resonance imaging demonstrated left temporal and posterior infarction in the posterior cerebral artery region. Single photon emission computed tomography revealed decreased blood flow in the left inferior temporal, parahippocampal, fusiform, lingual and inferior occipital gyri. There were no significant lesions nor any decreased of blood flow in the angular gyrus.

Conclusions: It is suggested that reading and writing of ideograms such as Kanji is related not only to the angular gyrus but also to the posterior inferior temporal lobe and medial posterior lobe of the visual cortex.