Blog #34: The Petit Mal (Absence) Seizure

(This blog was originally posted on June 1, 2013)

 

Is some young person a daydreamer, staring or blinking and not paying attention? Could it be a petit mal seizure? Sure, everyone can do these things. Everyone “tunes out” the outside world occasionally, but not excessively, and not to the point where they will not respond to you.

Petit mal seizures last only seconds and can happen many times each day. If you are suspicious that it is not just daydreaming, try this at-home-diagnostic-procedure for petit mal epilepsy. I have done this many times in my office with positive diagnostic results. Have the person sit and breathe hard, deeply and fast (hyperventilate) for up to two minutes. Expect this to cause some mild, light-headed, dizzy feeling. If petit mal epilepsy is the problem, probably, but not always, the person will suddenly stop the hyperventilation, stare or blink, and not respond to you. After 10-15 seconds, the person will get right back to hyperventilating and be unaware that he had just interrupted it. He will not know that he had just induced a petit mal seizure. Your physician will document what you found with an EEG (electroencephalogram or brain wave test) and start effective medications that will most likely stop the seizures from occurring.

 

The “petit mal” or “absence” seizure occurs in fewer than 8% of epilepsy patients. They are specific to children, the majority of which are girls. It is believed that petit mal seizures originate deep within the central areas of the brain. A genetic, inherited mechanism seems common. This type of epilepsy usually begins after age three years and usually disappears spontaneously in the late teens. Petit mal seizures can occur up to 50-100 times per day. During the seizure, the child stops talking or walking, without falling, for seconds and then resumes the activity as though nothing had happened. Friends and unsophisticated observers may consider the patient as “ditzy” and strange without realizing the presence of any medical impairment. People can suffer petit mal seizures for years before a correct diagnosis of epilepsy. Some patients assume that their inexplicable spells happen in everyone since they are so common in their own daily life. If the petit mal seizures do not cease by the late teen years, they usually transform into grand mal convulsions with tongue biting, incontinence and loss of consciousness. Unlike the tonic-clonic seizure that I described in Blog #33, there is no loss of body tone or convulsion during a petit mal seizure. There is no warning (aura) that the seizure will occur.

A petit mal seizure lasts between 10 and 15 seconds, during which time the individual appears to be “spacing out” with a motionless stare. There often is upward rolling of the eyes, or drooping of eyelids or mild twitching of eyelids and blinking. When the seizure is over, the person is immediately alert and aware of the environment/surroundings. The person will act as if nothing happened and be totally unaware that he or she had blanked out. If no one witnessed the event to tell the person about the seizure, i.e. the loss of contact with the environment, the patient may only realize that something happened after “missing” what someone had said during a conversation or the dialogue in a television program or movie in which he was particularly interested. Unlike a daydream, where the person is aware that his mind was focused on something, the petit mal patient’s mind is completely blank.       

Petit mal seizures can be precipitated by breathing fast and hard (hyperventilation) and by flashing lights. This light effect is produced naturally when moving through an area where sunlight shines intermittently through tree branches or from videogames or strobe lights. Therefore, the neurologist tests a patient for petit mal seizures with specific techniques during an EEG test. These include the person hyperventilating for a short period. The EEG test also includes a flashing strobe light while the patient lies under the lamp with closed eyes. Peculiarly, petit mal epilepsy can be especially sensitive to certain frequencies of the flashing lights. During the test, the light flashes go off at incremental speeds starting slowly and then up to 40 flashes per seconds. The classic petit mal EEG abnormality is called the “three spike-wave complexes per second” that occur throughout the brain.  Stress (both physical and emotional) can also elicit a seizure for people with epilepsy.

There is no immediate first-aid treatment for a petit mal seizure. The person will return to a fully alert and aware state within 15 seconds. You want to help the person get out of the path of oncoming traffic if the seizure occurred while he or she is crossing the street and prohibit driving until there is full control.

Lance Fogan, M.D. is Clinical Professor of Neurology at the David Geffen School of Medicine at UCLA. DINGS is his first novel.