左側頭葉の萎縮と失語症状を示し，非定型ピック病への進展が疑われた2症例

Two Patients with Localized Atrophy of the Left Temporal Lobe Presenting with Aphasia, This Showing the Possibility of Progression toward Atypical Pick's Disease

抄録

　非定型ピック病は，臨床・画像所見の特徴からピック病に含まれるが，神経病理学的にはピック小体を伴うタウオパチーである狭義のピック病とは異なり，病態機序不明の変性疾患である。本研究では，非定型ピック病への進展が疑われる2症例について報告し，初期の病態について検討した。症例1では，語義失語とともに，形態画像所見で左側頭葉前方部と外側底面にほぼ限局した萎縮が認められた。症例2では，症例1よりも高度な語義失語や軽度の前頭葉症状とともに，左側頭葉を中心としたより広範な萎縮が認められた。今後は，両症例とも萎縮がさらに進行し，前頭葉症状もより顕著となって，非定型ピック病に進展する可能性が高いと考えられる。

Summary

　Atypical Pick's disease without Pick bodies (aPiD) is a form of degenerative dementia that has a pathomechanism different from that of Pick's disease with Pick bodies (PiD). In this study, we report two patients with localized atrophy of the left temporal lobe presenting with aphasia. Case 1 a female patient showed word-finding difficulty, semantic memory disorder and difficulty in reading and writing Chinese characters, and her neuroimagings exhibited localized atrophy of the left temporal tip and anterior portion of the baso-lateral temporal lobe. As she experienced no other difficulties, this case supports the previous finding that the degeneration of the left anterior temporal lobe is responsible for semantic aphasia. Case 2 a female patient showed severer cognitive disabilities than recorded in case 1, and her neuroimagings exhibited more extensive atrophy of the left anterior temporal lobe. These two patients showed the possibility of progression toward aPiD, and may be helpful to clarify the concept of frontotemporal lobar degeneration.