Progressive supranuclear palsy is a rare disease that steadily destroys nerve cells in the parts of the brain that control eye movements, breathing, and muscle coordination. The loss of nerve cells causes palsy, or paralysis, that slowly worsens as the disease moves on. The palsy has effects on capability to move the eyes, relax the muscles, and control balance.
Progressive supranuclear palsy is a disease of middle age. Symptoms usually begin in the 60s, barely before age 45 or after age 75. Men develop PSP more often than women do. It affects 3 to four people per million every year.
Prognosis for progressive supranuclear palsy: is affecting the brainstem, the fundamental ganglia, and the cerebellum. The brainstem is found at the top of the spinal cord. It controls the most basic functions required for survival-the involuntary ( unwilled ) movements like breathing, blood pressure, and heart rate. The brainstem has three parts : the medulla oblongata, the pons, and the midbrain. The parts influenced by PSP are the pons, which controls facial nerves and the muscles that turn the eye outward, and the midbrain, the visual center. The fundamental ganglia are islands of nerve cells located deep within the brain. They are involved in the initiation of voluntary ( willed ) movement and control of emotion. Damage to the fundamental ganglia causes muscle rigidity ( spasticity ) and shocks. The cerebellum is located at the base of the skull. It controls balance and muscle coordination.
Vision is controlled by groups of cells called nuclei in the brainstem. In PSP, the nuclei continue to function, but the mechanisms that control the nuclei are annihilated. The term supranuclear suggests that the damage is done above ( supra ) the nuclei. Patients with PSP have problems with voluntary ( willed ) eye movement. Initially, the difficulty only happens in making an attempt to look down. As the illness progresses, capability to move the eyes right and left is also affected. However reflex or unwilled eye movements remain standard. Thus, when the patient’s head is angled upwards, the eyes move to look down. These reflex movements remain normal till late in the course of the disease. The higher eyelids might be pulled back, the eyebrows raised, and the brow wrinkled, causing a standard wide-eyed stare. Rate of blinking may fall from the normal 20-30 per minute to 3 to five per minute. It becomes tricky to walk downstairs, to maintain eye contact during conversation, or to move the eyes up and down to read.
The earliest symptoms of PSP may be frequent falls or stiff, slow movements of the legs and arms. These symptoms may appear as much as five years before the characteristic vision Problems. Walking becomes very awkward, and some patients have a tendency to lean and fall backward. Facial muscles might be puny, causing slurred speech and difficulty swallowing. Sleep may be troubled and thought processes slowed. Although memory remains intact, the slowed speech and thought patterns and the rigid facial expression could be mistaken for senile dementia or Alzheimer’s disease. Emotional reactions may become exaggerated and unbecoming, and the patient may experience anxiety, depression, and agitation.
The root of PSP isn’t known. Most of the people who develop PSP come from families with no history of the disease, so it does not appear to be inherited, except in certain rare instances. People who have PSP appear to lack the neurotransmitters dopamine and homovanillic acid in the fundamental ganglia. Neurotransmitters are chemicals that help carry electrical impulses along the nervous system. Transmitting structures in brain cells called neurofibrils become disorganised ( neurofibrillary tangles ). Neurofibrillary tangles are also found in Alzheimer’s disease, but the pattern is somewhat different. Check out also cerebral palsy information.
