左前頭葉腫瘍で生じた超皮質性感覚失語

Transcortical Sensory Aphasia in a Patient with Metastatic Brain Tumor in the Left Frontal Lobe

I．はじめに

　一般に，左前頭葉損傷では，運動性失語に代表される非流暢型の失語症が出現する^6,10,11）．すなわち，発話量に乏しく，構音の歪みや韻律の障害，失文法，喚語障害，発話時の努力を特徴とするBroca失語や，有用な自発話が減少しているが，復唱は保たれている超皮質性運動失語などがその代表的なタイプである．一方，左前頭葉損傷で流暢型の失語症を認めたという報告も稀にみられるが^4,9），詳細は明らかではない．今回，われわれは左前頭葉の転移性脳腫瘍によって超皮質性感覚失語を呈した1例を報告し，若干の考察を加える．

We reported a case of a 62-year-old right-handed woman who had transcortical sensory aphasia caused by a metastatic brain tumor in the left frontal lobe. She had mild right hemiparesis involving the face, without hyperactive tendon reflexes. She had neither sensory disturbance nor other cranial nerve deficits. Her spon-taneous speech was fluent, and she sometimes had echolalia. Her object naming, word fluency, verbal com-prehension and writing were severely disturbed. This contrasted with full preservation of repetition of phonemes and short sentences. Reading of words was preserved. CT scan revealed a subcortical lesion in the left superior frontal gyrus. Gd-enhanced MRI showed a ring-enhanced mass lesion in the frontal lobe outside of Broca's area. We thereby concluded that transcortical sensory aphasia may be caused by frontal lobe lesion independent of the perisylvian speech areas.