Table 3 Synopsis of imaging features of parkinsonian syndromes

sMRI

Asymmetric atrophy of the posterior frontal and parietal lobes and cerebral peduncle contralateral to symptoms

“Mickey mouse” and “hummingbird” signs secondary to brainstem atrophy

MSA-p—lateral rim of T2/PD hyperintensity adjacent to putamen (1.5 T)

MSA-c—Hot cross bun sign, brainstem and cerebellar atrophy and T2 hyperintensity

SW/T2*

MRS

DTI

Reduced FA in the pre- and post-central gyri, cingulum, and SMA

Reduced FA in the posterior frontal lobes and cerebellar peduncles

Reduced FA in the superior, middle, and inferior cerebellar peduncles and in the corona radiata and commissural fibers

rsfMRI

Hypoconnectivity of the lateral visual and auditory networks and hyperconnectivity of the salience and executive control networks

Hypoconnectivity of the lateral visual, auditory, cerebellar, and insular networks

Hypoconnectivity of the DMN, sensorimotor network, visual associated cortices, and cerebellum

ASL

Hypoperfusion of the cerebellum

FDG-PET

Hypometabolism involving the primary cortices and additionally basal ganglia contralateral to the affected side

Hypometabolism involving the brainstem and midline frontal cortex

Hypometabolism involving the bilateral putamina and cerebellar hemispheres

Amyloid PET

May show uptake in CBS (not pure CBD) secondary to underlying amyloid-related NDD

Tau PET

Uptake of 18-F-PI-2620 in frontoparietal cortices and basal ganglia structures contralateral to affected side

Uptake of 18-F-PI-2620 in the basal ganglia and brainstem structures

DAT/Dopamine imaging

Asymmetric decreased striatal uptake caudate relatively more impacted than putamen

Decreased striatal uptake

Reduced uptake within the putamina