Todd's paralysis is a form of neurological condition people with epilepsy experience after having a seizure.
It involves a brief period of paralysis that can be partial or complete, but commonly happens on just one side of their body. The paralysis may last from an hour and a half to thirty-six hours. The average period of time for Todd's paralysis is fifteen hours - after which it resolves entirely.
Medical science is not sure of the causes of Todd's paralysis. The current theories propose certain biological processes in a person's brain that involve a, 'slow down,' in either the energy output of neurons, or in the person's motor centers in their brain. Distinguishing between Todd's paralysis and a stroke, which it may resemble, is important because a stroke requires completely different treatment.
The period of time immediately following a seizure is referred to as the, 'postictal state.' During this period of time, a person's brain is still recovering from the major changes experienced by the seizure. The person commonly is experiencing confusion and drowsiness during the postictal state. At times, the symptoms are even more dramatic and pronounced and can even involve severe weakness or even paralysis of a limb or one side of the person's body, referred to as, 'hemiparesis.' The person may experience sensations that include pronounced vision changes, numbness, or blindness. Todd's paralysis often affects people with epilepsy, although is can happen after any form of seizure.
Causes and Symptoms of Todd's Paralysis
A seizure involves an episode of abnormal electrical activity in a particular part of a person's brain. There are a number of forms of seizures. Seizures can affect any specific part of a person's brain, or they can spread to affect a wider area of a person's brain. The behavior of a person experiencing a seizure can vary from a simple and brief staring episode to complete loss of consciousness accompanied with involuntary muscle activity. During the postictal period, even though the seizure itself has stopped, the person's brain is continuing to recover from the electrical discharges it has experienced which precipitated the seizure activity. During this time period the person can remain less responsive than usual, they may be drowsy, or confused. Todd's paralysis is believed to happen because of depressed activity in the area of the person's brain where the seizure activity occurred.
The symptoms of Todd's paralysis depend upon the area of the person's brain where the seizure occurred. For example; if the seizure happened in the person's motor cortex, the part of the brain that is responsible for the purposeful movement of the person's muscles, Todd's paralysis can result in hemiparesis - the person will be unable to more their muscles on one-half of their body. Because the occipital lobe, located at the lower-back portion of a person's brain, is responsible for vision, an occipital loe seizure might result in visual changes or even blindness during the postictal period. Tracking the specific symptoms of Todd's paralysis might assist a doctor in diagnosing the particular portion of a person's brain where the seizures they are experiencing are occurring.
The symptoms of Todd's paralysis often disappear within minutes to hours of their initial onset. On rare occasions, for some people, the symptoms can last for thirty-six to forty-eight hours. Eventually the symptoms of Todd's paralysis disappear and the person's functionality returns.
Diagnosing Todd's Paralysis
Reaching a diagnosis of Todd's paralysis can be crucial because the symptoms may closely resemble those of a stroke. A stroke involves an injury to a person's brain due to oxygen deprivation after bleeding or the blockage of a person's artery. The two diagnosis are quite different, making a clear diagnosis very important.
In general, Todd's paralysis can be easily diagnosed when it happens after a person has a documented seizure. Quick resolution of the symptoms of Todd's paralysis is another means of distinguishing between it and a stroke. When a diagnosis remains unclear tests can be run, to include an electroencephalogram or EEG, a test that records information about the person's brain electrical activity. A Magnetic Resonance Imaging Scan or MRI may also be performed. Persons who have experienced a seizure will present with an abnormal EEG, while those who have experienced a stroke and have an MRI scan might present with images revealing an area of damage.
Treatment and Todd's Paralysis
Todd's paralysis is one indication that a person's has experienced a seizure, potentially associated with epilepsy. The outcome is dependent upon the effects of the seizure and the subsequent treatment of epilepsy. There is no particular treatment needed for Todd's paralysis itself. The persons needs to rest as comfortably as they possibly can until the symptoms of paralysis disappear. The symptoms often resolve within minutes to hours, although they may last for a day or two. The treatment for Todd's paralysis is both symptomatic and supportive based on the fact that the paralysis disappears quickly. Due to the quick and complete disappearance of the symptoms of Todd's paralysis, rehabilitation is not needed.