Posted by ccf neuro M.D. on April 14, 1997 at 22:55:10:
In Reply to: Complicated migraine or TIA posted by Debbie M on April 09, 1997 at 15:38:35:
: My 12 year old daughter had what was first Dx. as a TIA
in Sept/96. She had marked weakness on one side, vision
field was reduced in one eye, confusion, slurred speech,
and was dragging her left foot, she also did not know her
name could not identify objects, and was not able to write.
when she left the hospital she was dx. as having a TIA.
Since that time she has had about 4 migraines but not at all
like the first one. They are now calling the first attack
a complicated migraine. Why the difference now? Thanks
for any help.
A TIA, or transient ischemic attack, occurs when a part of the brain is temporarlily, usually briefly, deprived of blood flow, resulting in the temporary loss of function of that part of the brain in which the blood flow is temporarily lost. Migraine headaches result in an abnormal constriction or narrowing of one of the arteries in the brain, followed subsequently by abnormal dilation or widening of the same or nearby arteries, which generates the pounding, throbbing pain of the migraine. On occasion, the initial portion of the migraine where the blood vessel is CONSTRICTING is so severe that it causes a large enough reduction in blood flow to the part of the brain the artery supplies to produce neurologic symptoms very similar to those caused by a TIA. The term "TIA", however, is restricted to describing instances where the temporary loss of blood flow is caused by a blood clot temporarily clogging the affected artery before it busts up in its own into smaller pieces. The lack of blood flow in the case of
migraines that are "complicated" by neurologic symptoms, by contrast, is due to SPASM or narrowing of the artery rather than by a blood clot. Typically, also, the duration of symptoms in complicated migraines is an hour, whereas for a TIA the duration is 5 minutes or less. You should be aware that the diagnosis of "complicated migraine" can only be made after excluding other more serious illnesses such as tumors or arteriovenous malformations (abnormal tangles of blood vessels in the brain), that can produce remarkably similar symptoms. Presumably, your daughter has already had an MRI scan, or at least a CAT scan with contrast to rule out these more sinister but rarer possibilities. Complicated migraines often but not always run in families and are often controllable by the same drugs used to prevent regular migraines. Sometimes, the patient has the neurologic symptoms WITH a headache, in which case the episode is called a "complicated migraine." Other times, theneurologic symptoms may occur WITHOUT the
headache, in which case the spell is called a TRANSIENT MIGRAINOUS ACCOMPANIMENT, or "TMA"--- note the similarity to "TIA", which is appropriate since both episodes are produced by diminished blood flow to a portion of the brain. On rare occasions, the spasm or narrowing of the artery may become so severe that the artery clots off--- in which case you get a STROKE. If your daughter EVER has neurologic symptoms lasting more than about 45 minutes, you should bring her to the nearest emergency room IMMEDIATELY---- DO NOT WAIT beyond that time interval, because if you do and she has had a stroke, she will miss out on the opportunity to have the stroke reversed by clot-buster drugs that must be administered within 3 hours of stroke onset in order to have a chance of working. I would suggest that you have either a pediatric neurologist or a headache doctor treat your daughter's complicated migraines/TMAs as prompt control of these is desirable. I hope this information answers your question in a way you can
understand, and helps you understand why the episode your daughter initially had (a TMA) was easily misinterpreted as a TIA, as her history of migraine headaches was not known at the time and, by coincidence, her first migraine symtpom just happened to be a TMA.