Clinicopathological staging of frontotemporal dementia severity: correlation with regional atrophy

The pattern and degree of brain atrophy in frontotemporal dementia (FTD) has the potential for use as an aid in the diagnosis of this disorder and its differentiation from other neurodegenerative diseases. However, before this can occur, the sequence and progression of atrophy needs to be fully elucidated. Recently, we have described a four-point scheme for staging the severity of degeneration in FTD, which correlates with both duration of disease and severity of dementia [Broe M., et al.: Neurology 2003;60:1005-1011]. When volumetric analysis is performed in post-mortem-confirmed cases of FTD, atrophy of all lobes is present by stage 2 and then progresses with successive stages. Within each lobe, there is variation in the degree of atrophy between different functionally discreet brain regions with some regions showing marked atrophy and others showing little. Much of the frontal lobe, the amygdala and hippocampus are severely atrophic by stage 2, suggesting that they are some of the earliest areas affected in FTD.