Armstrong criteria:1 (A) proposed clinical phenotypes or syndromes; (B) proposed diagnostic criteria for CBD; (C) exclusion criteria for both clinical research criteria for probable sporadic CBD and possible CBD
| (A) Syndrome | Feature |
|---|---|
| Probable CBS | Asymmetric presentation of two of: (a) limb rigidity or akinesia, (b) limb dystonia, (c) limb myoclonus plus two of: (d) orobuccal or limb apraxia, (e) cortical sensory deficit, (f) alien limb phenomena (more than simple levitation) |
| Possible CBS | May be symmetric: one of: (a) limb rigidity or akinesia, (b) limb dystonia, (c) limb myoclonus plus one of: (d) orobuccal or limb apraxia, (e) cortical sensory deficit, (f) alien limb phenomena (more than simple levitation) |
| Frontal behavioural-spatial syndrome (FBS) | Two of: (a) executive dysfunction, (b) behavioural or personality changes, (c) visuospatial deficits |
| NAV of primary progressive aphasia | Effortful, agrammatic speech plus at least one of: (a) impaired grammar/sentence comprehension with relatively preserved single word comprehension or (b) groping, distorted speech production (apraxia of speech) |
| Progressive supranuclear palsy syndrome (PSPS) | Three of: (a) axial or symmetric limb rigidity or akinesia, (b) postural instability or falls, (c) urinary incontinence, (d) behavioural changes, (e) supranuclear vertical gaze palsy or decreased vertical saccade velocity |
| (B) | Clinical research criteria for probable sporadic CBD | Clinical criteria for possible CBD |
|---|---|---|
| Presentation | Insidious onset and gradual progression | Insidious onset and gradual progression |
| Minimum duration of symptoms, years | 1 | 1 |
| Age at onset, years | ≥50 | No minimum |
| Family history (two or more relatives) | Exclusion | Permitted |
| Permitted phenotypes (see table 4 for criteria) | (1) Probable CBS or (2) FBS or NAV plus at least one CBS feature (a–f) | (1) Possible CBS or (2) FBS or NAV or (3) PSPS plus at least one CBS feature (b–f) |
| Genetic mutation affecting tau (eg, MAPT) | Exclusion | Permitted |
| (C) | ||
| Exclusion criteria for both clinical research criteria for probable sporadic CBD and possible CBD | ||
| Evidence of Lewy body disease, multiple system atrophy, Alzheimer's disease or amyotrophic lateral sclerosis; semantic or logopenic variant primary progressive aphasia; structural lesion suggestive of focal cause; granulin mutation or reduced plasma progranulin levels; TDP-43 or fused in sarcoma (FUS) mutations | ||
CBD, corticobasal degeneration; CBS, corticobasal syndrome; NAV, non-fluent/agrammatic variant.