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Or the Steele–Richardson–Olszewski syndrome.
A degenerative disease involving the gradual deterioration and death of specific areas of the brain.
Males and females are affected approximately equally.
There is no racial, geographical or occupational predilection.
Approximately six people per 100,000 population have PSP.
The average age at symptoms onset is 63.
Survival from onset averages 7 years.
Initial symptoms in two-thirds of cases are loss of balance, lunging forward when mobilizing, fast walking, bumping into objects or people, falls. changes in personality, general slowing of movement, and visual symptoms.
Subsequently dementia, loss of inhibitions ability to organize,slurring of speech, difficulty swallowing, and difficulty moving the eyes, particularly in the vertical direction occur to varying degrees.
Because these patients are unable to look up or down., they are subject to falls.
Additional symptoms and findings include poor eyelid function, facial muscles contracture, a backward tilt of the head, stiffening of the neck muscles, sleep disruption, urinary incontinence and constipation.
Patients have difficulty reading due to the inability to look down well.
Voluntary eye movements are inhibited and they have inability to make vertical saccades, which is often worse with downward saccades.
Patients tend to have difficulty looking down, with a downgaze palsy, followed by the addition of an upgaze palsy.
Vertical gaze paresis will correct when the examiner passively rolls the patient’s head up and down as part of a test for the oculocephalic reflex
Difficulties with convergence is typical, and patients may have trouble coming focusing at short distances, and may complain of diplopia.
Cause is unknown.
Fewer than 1% have a family member with the same disorder.
A tau protein gene variant called the H1 haplotype, located on chromosome 17, has been linked to PSP.
The H1 haplotype appears to be necessary but not sufficient to cause PSP.
PSP affected brain cells are both neurons and glial cells.
The neurons display neurofibrillary tangles, which are clumps of tau protein.
Their chemical composition is usually different than in Alzheimer’s disease and is similar to that of tangles seen in corticobasal degeneration.
Tufts of tau protein in astrocytes, or tufted astrocytes, are also considered diagnostic.
The principal areas of the brain affected with PSP are the:
basal ganglia, particularly the subthalamic nucleus, substantia nigra and globus pallidus
brainstem, particularly the portion of the midbrain where supranuclear eye movement resides
cerebral cortex, particularly that of the frontal lobes
dentate nucleus of the cerebellum
spinal cord, particularly the area where some control of the bladder and bowel reside
Diagnosis
MRI may show atrophy in the midbrain with preservation of the pons giving a hummingbird sign appearance.
It is frequently misdiagnosed as Parkinson’s disease, due to slowed movements and gait difficulty.
It may be confused with Alzheimer’s disease because of the behavioral changes.
Has no known cure.
Management is primarily supportive.
Cases are often split into two subgroups, PSP-Richardson, the classic type, and PSP-Parkinsonism.
In the PSP-Parkinson type a short-term response to levodopa can be obtained.
Patients with PSP need occupational therapy, speech-language pathology for motor speech changes typically a spastic-ataxic dysarthria, and physical therapy for balance and gait problems.
Rehabilitation programs include limb-coordination activities, tilt-board balancing, gait training, strength training, resistive exercises and isokinetic exercises stretching, and mobility aids.
All patients eventually lose their ability to walk and will need a wheelchair.
Severe dysphagia often follows loss of mobility and death often occurs in a matter of months.
Pneumonia is a frequent cause of death.