(See also Overview of Movement and Cerebellar Disorders Overview of Movement and Cerebellar Disorders Voluntary movement requires complex interaction of the corticospinal (pyramidal) tracts, basal ganglia, and cerebellum (the center for motor coordination) to ensure smooth, purposeful movement... read more .)
The cause of progressive supranuclear palsy is unknown.
Neurons in the basal ganglia and brain stem degenerate; neurofibrillary tangles containing an abnormally phosphorylated tau protein are also present.
Symptoms and Signs of PSP
Symptoms of progressive supranuclear palsy usually begin in late middle age.
The first symptom may be
Difficulty looking up or down without moving the neck or difficulty climbing up and down stairs
Voluntary eye movements, particularly vertical, are difficult, but reflexive eye movements are unaffected.
Movements are slowed, muscles become rigid, and axial dystonia develops. Patients tend to fall backward.
Dysphagia, dysarthria with emotional lability (pseudobulbar palsy), depression, and disordered sleep are common. Resting tremor may develop.
Dementia eventually occurs. Many patients become incapacitated within about 5 years and die within about 10 years.
Progressive supranuclear palsy (PSP) has several different clinical types based on the predominant symptoms or signs (1 Diagnosis references Progressive supranuclear palsy is a rare, degenerative central nervous system disorder that progressively impairs voluntary eye movements and causes bradykinesia, muscular rigidity with progressive... read more ):
Richardson syndrome: Classic progressive supranuclear palsy with progressive supranuclear ophthalmoplegia and severe balance problems (the most common form, in ≥ 70% of cases)
PSP-P: Parkinsonian type of progressive supranuclear palsy, which responds to levodopa, resulting in transient, slight improvement
PSP-PAFG: Characterized by pure akinesia with freezing of gait
PSP-PGF: Characterized by progressive gait freezing
PSP-PNFA (PSP-SL): Characterized by progressive nonfluent aphasia or speech or language disorders
PSP-AOS: Characterized by apraxia of speech
PSP-FTLD (PSP-F): Characterized by frontotemporal degeneration
PSP-CBS: Characterized by corticobasal syndrome, causing profound asymmetric symptoms
PSP-MN (PSP-PLS): Characterized by motoneuron symptoms related to primary lateral sclerosis Primary lateral sclerosis Amyotrophic lateral sclerosis and other motor neuron diseases are characterized by steady, relentless, progressive degeneration of corticospinal tracts, anterior horn cells, bulbar motor nuclei... read more
Other possible forms include
PSP-C: Characterized by cerebellar signs
PSP-PI: Characterized by postural instability
In forms other than Richardson syndrome (nonclassical forms [called atypical parkinsonism]), ophthalmoplegia may be delayed by years.
Diagnosis of PSP
Diagnosis of progressive supranuclear palsy is clinical.
MRI is usually done to exclude other disorders. In advanced cases, MRI shows a characteristic decrease in midbrain size that is best seen on midsagittal views and that causes the midbrain to be shaped like a hummingbird or emperor penguin. On axial views, the midbrain may resemble a morning glory (2 Diagnosis references Progressive supranuclear palsy is a rare, degenerative central nervous system disorder that progressively impairs voluntary eye movements and causes bradykinesia, muscular rigidity with progressive... read more ).
1.Höglinger GU, Respondek G, Stamelou M, et al: Clinical diagnosis of progressive supranuclear palsy: The Movement Disorder Society criteria. Mov Disord (32) 6,:853–864, 2017. doi: 10.1002/mds.26987. Epub 2017 May 3.
2. Adachi M, Kawanami T, Ohshima H, et al: Morning glory sign: a particular MR finding in progressive supranuclear palsy. Magn Reson Med Sci 3 (3):125–132, 2004.
Treatment of PSP
Treatment of progressive supranuclear palsy focuses on relieving symptoms but is unsatisfactory. Occasionally, levodopa and/or amantadine partially relieve rigidity. Physical and occupational therapy may help improve mobility and function and reduce the risk of falls.
Because progressive supranuclear palsy is fatal, patients should be encouraged to prepare advance directives Advance Directives Advance directives are legal documents that extend a person's control over health care decisions in the event that the person becomes incapacitated. They are called advance directives because... read more soon after the disorder is diagnosed. These directives should indicate what kind of medical care people want at the end of life.
The first symptom of classic progressive supranuclear palsy may be difficulty looking up or down without moving the neck or difficulty climbing up and down stairs.
Diagnose based on symptoms, but do MRI to exclude other disorders.
Focus on relieving symptoms; consider levodopa and/or amantadine to relieve rigidity, and prescribe physical and occupational therapy.