|
The Japanese journal of neuropsychology
|
|
Full Text of this Article
in Japanese PDF (527K)
|
ArticleTitle
|
Primary progressive aphasia: transition of its clinical concept |
Language |
J |
AuthorList |
Kenjiro Komori |
Affiliation |
Department of Neuropsychiatry, Neuroscience, Ehime University Graduate School of Medicine |
Publication |
Japanese Journal of Neuropsychology: 26 (4), 255-263, 2010 |
Received |
|
Accepted |
|
Abstract |
The clinical concept of primary progressive aphasia (PPA) proposed by Mesulam deserves landmark work for resulting world-wide recognition about the nature of progressive aphasic syndromes which used to be far less concerned in contrast to the traditional aphasic syndromes caused by cerebrovascular accidents. At first, it was reported as a slowly progressive language deterioration without generalized cognitive or behavioural impairment associated with enlargement of the left sylvian fissure without any distinctive neuropathological background. Once clinical diagnostic criteria of PPA was established with two dominant subtypes; progressive nonfluent aphasia (PNFA) associated with focal atrophy of the peri-sylvian area on the left, and progressive fluent aphasia, called semantic dementia (SD) with focal atrophy on the anterior temporal lobes more marked on the left. They are also components of frontotemporal lobar degeneration (FTLD). However, the clinical concept of the PPA underwent considerable changes. Finally three variants of PPA were recognized: PPA-agrammatic with focal atropy around the inferior frontal gyrus (Broca's area), SD with anterior temporal lobe atrophy, and logopenic progressive aphasia (LPA), characterized word-finding hesitation with frequent phonological errors though preserved grammatical comprehension, with significant atrophy of the temporoparietal junction area and posterior temporal lobe on the left. Furthermore, clinicopathological contributions on PPA have been emphasized: FTLD with tauopathies for PPA-agrammatic, FTLD with ubiquitin/TDP-43 proteinopathies for SD, and Alzheimer's disease (AD) for LPA. Recent approaches to the pathognomy of PPA are extending across behavioral observation of patients, neuroimaging and the molecular biomarkers. However, considerable controversies about clinical concept of PPA may still remain. |
Keywords |
primary progressive aphasia (PPA), progressive non-fluent aphasia (PNFA), semantic dementia (SD), PPA-agrammatic, logopenic progressive apahasia (LPA) |
|