Transcortical alexia with agraphia following a right temporo-occipital hematoma in a right-handed patient.

We describe the case of a 51-year-old right-handed man who was affected by a transcortical alexia with agraphia and aphasia. Transcortical alexia produces errors in both reading and writing while copying is preserved. The patient had a severe alexia and was unable to read letters, words or sentences. Language examination showed mild aphasia with reduced fluency, intermittent paraphasia but a good comprehension and a normal repetition. Spontaneously and from dictation, writing was impaired by an agraphic jargon, but copying was excellent even though the patient was unable to read his own written production. There was no visual agnosia nor hemianopia. CT scan and MRI of the brain showed that there was a single right temporo-occipital hemorrhage but no lesion in the left hemisphere. Following surgical evacuation of the hematoma, the patient improved. One month after onset, his language was quite intact and reading was possible. We hypothesize that this particular syndrome was the result of a double disconnection: alexia would result from a disconnection of the right angular gyrus and the occipital associative areas by a subangular lesion; agraphia would result from a disconnection of the right angular gyrus and the semantic store, probably located in the right hemisphere.