View source for Progressive supranuclear palsy (Steele-Richardson-Olszewski)

'''Diagnosis'''

Clinical criteria; all core diagnostic features and no exclusion features must be present (Litvan et al, 1996)

1) Core diagnostic features of probable PSP

:a. Gradually progressive disorder

:b. Onset at age 40 or later

:c. Vertical supranuclear palsy (upward or downward gaze) and prominent postural instability with fall in the first year of disease onset

:d. No evidence of other diseases that could explain the above features

2) Core diagnostic features of possible PSP

:a. At least one of the following must be present:

::i. Vertical supranuclear palsy (upward or downward gaze)

::ii. Both slowing of vertical saccades and prominent postural instability with falls in the first year of disease onset

3) Supportive diagnostic features of PSP

:a. Symmetric akinesia or rigidity, proximal > distal

:b. Abnormal neck posture

:c. Early dysphagia and dysarthria

:d. Poor or absent response of Parkinsonism to levodopa

:e. Early onset of cognitive impairment (about 20% of PSP patients initially present with features of FTD such as behavioral changes or language impairments and up to 30% of PSP patients will meet criteria for bvFTD) including at least two of the following:

::i. Apathy

::ii. Impairment of abstract thought

::iii. Decreased verbal fluency

::iv. Utilization or imitation behavior

::v. Frontal release signs

:f. Neuropsychological pattern of performance with executive dysfunction and relatively preserved memory with good recognition

4) Exclusion criteria for PSP

:a. Recent history of encephalitis

:b. Alien limb syndrome, cortical sensory deficits, focal frontal or temporoparietal atrophy

:c. Hallucinations or delusions

:d. Cortical dementia of Alzheimer’s type (severe amnesia and aphasia or agnosia)

:e. Prominent, early cerebellar symptoms or prominent, early unexplained dysautonomia (marked hypotension and urinary disturbance)

:f. Severe, asymmetric Parkinsonism (e.g., bradykinesia)

:g. Whipple’s disease


Golbe and Ohman-Strickland created a clinical rating scale for PSP with good interrater reliability. Based on patient scores it was also a good independent predictor of survival. It comprised of 28 items across six categories, scored 0 to 100 (Golbe and Ohman-Strickland 2007). Examples include: 

* Daily activities (by history): withdrawal, irritability, dysphagia for solids, using a knife and fork / buttoning clothes / washing hands and face, falls, urinary incontinence, sleep difficulty
* Mentation / behavior: disorientation, bradyphrenia, emotional incontinence, grasping/imitative/utilizing behavior
* Bulbar: dysarthria, dysphagia
* Oculomotor: voluntary upward, downward, left, and right command movements, eyelid dysfunction, 
* Limb motor: limb rigidity, limb dystonia, finger tapping, toe tapping, apraxia of hand movement, tremor in any part
* Gait / midline: neck rigidity or dystonia, arising from chair, gait, postural stability, sitting down


'''Examination'''

- Neurological examination will generally show axial rigidity, narrow-based gait (despite history of falls), slowed vertical saccades, dysarthria, apathy/depression, slowed speech and thought process. As the disease progresses, the patient develops akinetic/rigid Parkinsonism, dystonia, ophthalmoplegia of the vertical gaze, verbal apraxia, pseudobulbar palsy, and frontal release signs (Finger 2016)

- Neuropsychological testing demonstrates slowed processing speed, especially on executive function and verbal fluency; comprehension and memory are relatively spared.


'''Imaging'''

T1 MRI of 71-year-old patient with PSP (Ljubenkov and Miller 2016)
- Sagittal view shows “hummingbird sign” including atrophic midbrain tegmentum (dashed arrow) resembling hummingbird’s head and a relatively preserved basis pontis (solid arrow) that resembles the hummingbird’s belly).


'''Pathology'''

- Pathology is generally 4R tau (PSP > CBD) (Ljubenkov and Miller 2016)


== References ==

Finger, E. C. Frontotemporal Dementias. Contin. Minneap. Minn 22, 464–489 (2016). https://pubmed.ncbi.nlm.nih.gov/27042904/

Golbe, L. I. & Ohman-Strickland, P. A. A clinical rating scale for progressive supranuclear palsy. Brain 130, 1552–1565 (2007). https://pubmed.ncbi.nlm.nih.gov/17405767/ 

Litvan, I. et al. Clinical research criteria for the diagnosis of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome): Report of the NINDS-SPSP International Workshop. Neurology 47, 1–9 (1996). https://pubmed.ncbi.nlm.nih.gov/8710059/

Ljubenkov, P. A. & Miller, B. L. A Clinical Guide to Frontotemporal Dementias. FOCUS 14, 448–464 (2016). https://pubmed.ncbi.nlm.nih.gov/31975825/