Magnetic resonance imaging (MRI) is often used to diagnose<unk> . MRI may show atrophy in the midbrain with preservation of the pons giving a "hummingbird" sign appearance and Mickey Mouse sign. Types Based on the pathological findings in confirmed cases of<unk> , it is divided into the following categories: * classical Richardson syndrome <unk> -RS) *<unk> -parkinsonism <unk> -P) and<unk> -pure akinesia with gait freezing <unk> -PAGF) * frontal<unk> ,<unk> -corticobasal syndrome <unk> -CBS),<unk> -behavioural variant of frontotemporal dementia <unk> -bvFTD) and<unk><unk>  non-fluent aphasia <unk> -PNFA) *<unk> -C *<unk>  induced by Annonaceae Richardson syndrome is characterized by the typical features of<unk> . In<unk> -P features of Parkinson’s Disease overlap with the clinical presentation of<unk>  and follows a more benign course. In both<unk> -P and<unk> - PAGF distribution of abnormal tau is relatively restricted to the brain stem. Frontal<unk>  initially presents with behavioral and cognitive symptoms, with or without ophthalmoparesis and then evolve into typical<unk> . The phenotypes of<unk> -P and<unk> -PAGF are sometimes referred as the ‘brain stem’ variants of<unk> , as opposed to the ‘cortical’ variants which present with predominant cortical features including<unk> -CBS,<unk> -bvFTD, and<unk> -PNFA. Cerebellar ataxia as the predominant early presenting feature is increasingly recognized as a very rare subtype of<unk>  <unk> -C) which is associated with severe neuronal loss with gliosis and higher densities of coiled bodies in the cerebellar dentate nucleus. Differential diagnosis<unk>  is frequently misdiagnosed as Parkinson's disease because they both involve slowed movements and gait difficulty, with<unk>  being one of a collection of diseases referred to as Parkinson plus syndromes. Both Parkinson's and<unk>  have an onset in late middle age and involve slowing and rigidity of movement. However, several distinguishing features exist. Tremor is very common with Parkinson's, but rare with<unk> . Speech and swallowing difficulties are more common and severe with<unk>  and the abnormal eye movements of<unk>  are essentially absent with PD. A poor response to levodopa along with symmetrical onset can also help differentiate<unk>  from PD. Patients with the Richardson variant of<unk>  tend to have an upright posture or arched back, as opposed to the stooped-forward posture of other Parkinsonian disorders, although<unk> -Parkinsonism (see below) can demonstrate a stooped posture. Early falls are also more common with<unk> , especially with Richardson syndrome.<unk>  can also be misdiagnosed as Alzheimer's disease because of the behavioral changes. Chronic traumatic encephalopathy shows many similarities with<unk> .
Progressive supranuclear palsy
Frontotemporal dementia and parkinsonism linked to chromosome 17
Multiple system atrophy
Corticobasal degeneration
Parkinson-plus syndrome
Parkinson's disease
Benign hereditary chorea
Alzheimer's disease