A gelastic seizure, also known as "gelastic epilepsy" is a rare type of seizure that involves
a sudden burst of energy, usually in the form of laughing or crying.
This syndrome usually occurs for no obvious reason and is uncontrollable.
It is slightly more common in males than females.
The term Gelastic originates from the Greek word "Gelos" which means laughter.
This syndrome can go for very long periods of time without a diagnosis, as it may appear
to be much like normal laughing or crying, if it occurs infrequently.
It has been associated with several different conditions such as temporal and frontal lobe
lesions, tumors, atrophy, tuberous sclerosis, hemangiomas, and post infectious foci, but
mainly hypothalamic hamartomas.
Signs and symptoms The main sign of a gelastic seizure is a sudden
outburst of laughter or crying with no apparent cause.
The laughter may sound unpleasant and sardonic rather than joyful.
The outburst usually lasts for less than a minute.
During or shortly after a seizure, an individual might display some twitching, strange eye
movements, lip smacking, fidgeting or mumbling.
If a person who suffers from the seizures is hooked up to an electroencephalogram it
will reveal interictal epileptic discharges.
This syndrome usually manifests itself before the individual reaches the age of three or
four.
The temporal lobes, and the hypothalamus are the areas of the brain with the most involvement
with these seizures.
This may cause learning disabilities, and faulted cognitive function as well.
It is not uncommon for children to have tonic-clonic seizures, and atonic seizures directly following
the seizure.
Those that are associated with hypothalamic hamartomas may occur as often as several times
hourly and typically begin during infancy.
Seizures that occur in infancy may include bursts of cooing, respirations, giggling,
and smiling.
Due to early hypothalamic-pituitary-gonadal axis activation in girls who suffer from the
seizures, it is not uncommon for them to display secondary sex characteristics before the age
of eight.
Diagnosis A diagnosis is difficult, especially in children,
due to the difficulty in differentiating between actual laughing or crying, versus a seizure
that involves laughing and crying.
In pre-verbal infants, a diagnosis may be impossible.
A long history must be taken with a description of all the signs leading to and during the
seizure.
The episodes can also be confused with behavioral and emotional disorders.
Some doctors ask parents to videotape the children's outbursts.
The tapes may be difficult to obtain, but can be very helpful in speeding up the difficult
diagnosis process.
Diagnosis is also complicated due to the many possible causes of the seizures.
Imaging is always helpful in an attempt to diagnose seizures caused by hypothalamic hamartoma.
If there is evidence of this, the diagnosis takes much less time.
Causes A gelastic seizure is typically caused by
a hypothalamic hamartoma, or a brain tumor.
A hypothalamic hamartoma is defined as a benign mass of glial tissue on or near the hypothalamus.
The size of the hamartoma can vary from one centimeter to larger than three centimeters.
They can cause several different types of seizures including a Gelastic Seizure.
These structures can be detected with different imaging modalities such as computed tomography
and magnetic resonance imaging.
A computed tomography scan of an individual with a hypothalamic hamartoma would reveal
an suprasellar mass with the same density as brain tissue.
Images of these masses are not enhanced with the use of contrast.
However, although a computed tomography scan may be useful in diagnosing the cause of a
seizure, in the case of a hypothalamic hamartoma, magnetic resonance imaging is the tool of
choice due to the cerebrospinal fluid which defines these masses.
Photon emission computed tomography may also be used.
This involves the use of a radiotracer which is taken up by the ictal region of the brain
which is typically where the tumor lies.
Gelastic seizures have been observed after taking a birth control pill).
Management Gelastic seizures are not responsive to therapy.
They can produce secondary seizure characteristics which may respond to medications or surgery.
These options are not a guaranteed cure, and depend solely on the individual patient’s
pathology.
The treatment depends on the cause of the seizures.
If the seizures are caused by a tumor, surgical removal can be attempted.
However, surgical removal is not always an immediate cure, and there can be complications.
Complications can include cerebral infarcts, and cognitive deterioration.
Hormonal treatment can be attempted to help individuals with precocious puberty.
Anti-epileptic drugs could be an option as well depending on the patient’s criteria.
These drugs could include carbamazepine, clobazam, lamotrigine, levetiracetam, oxcarbazepine
and topiramate.
However, none of these medications are capable of stopping the seizures from occurring, and
like any medication, there may be undesirable side effects.
There is also a specialized form of radiotherapy that may be an option depending on the tumor
type and location.
Once again, there are very few areas in the world that offer this treatment.
Gamma knife radiosurgery can be the treatment of choice when it comes to hypothalamic hamartomas.
It is a low risk option due to its lower frequency of neurological deficits.
It is recommended for patients with tumors that don’t come into contact with the optic
chiasm.
Prognosis Like many other types of seizures, gelastic
seizures are hard to control for an extended period of time.
The best outlook is for children suffering the seizures due to a benign tumor in their
hypothalamus.
The removal of these tumors can be effective not only for the frequency of the seizures,
but also the behavioral and cognitive symptoms that come along with the syndrome.Cases have
also been found that anti epileptic drugs have stopped seizures fully.
Media references Gelastic syncope was also referred to in one
paper also as "Seinfeld syncope" after an incident in which a patient repeatedly fainted
while watching an episode of Seinfeld.
References
External links Gelastic Seizures - Goran Brandberg, Orvar
Eeg-Olofsson Epilepsy Ontario - Gelastic seizures
Hypothalamic hamartomas and gelastic epilepsy MR imaging of hypothalamic hamartoma