[Anterior type dementia from the viewpoint of neuropathology].

Anterior type dementia is characterized by primary degeneration in the anterior brain region and represents pick symptom. Anterior type dementia includes several pathological disease entities, almost of them usually exhibit variation of atrophic brain regions in greater or lesser degree. This variation of each disease cause confusion, namely, the same clinical manifestations occur even if it is a different disease and diversely, different clinical manifestations can occur even if it is the same disease entity. This is the reason why discrepancy between clinical diagnosis and pathology diagnosis occurs sometimes in anterior type dementia. For reasonable clinical diagnosis, anterior type dementia, separate from neuropathological diseases entity, should be deal with clinical symptom-complex, which consists of frontotemporal dementia (FTD) progressive nonfluent aphasia (PA) and semantic dementia (SD). FTD, PA and SD have, though broadly, corresponding responsible brain lesion respectively.