EEG results

What is the significance of Bitemporal slowing on EEG?  My 10 year old has partial seizures, is on lamictal and depakote, and was recently hospitalized for 7 day video EEG study.  Surprisingly she did not have any sz even tho off most meds, and only had slowing.  Why would she not have sz when she had been having them almost daily before this while on meds?  Can meds like lamictal and depakote cause sz?

Thank you.

[CCF Neuro[P] MD, RPS]

Dear Barb:

Sorry that your daughter has seizures.  Bitemporal slowing usually means that there is a cortical dysfunction in both temporal lobes.  But it can also mean that there is seizure potential in the temporal lobes if the slowing is rhythmical such as in temporal intermittent slow activity (usually seen in some adult temporal lobe epilepsy patients).  It can also mean nothing.  Alot depends on how much slowing, if it was rhythmical, continuous, or ....   EEG is very subjective and interpretation can be varying depending on the reader.  Seizures are episodic and one can go many days or weeks without having an EEG abnormality or seizures in some patients.  One never knows.  If one removes seizure medications too fast, the answer is a definite yes, or if in very high concentrations, yes.

I hope that I didn't confuse you.

Sincerely,

CCF Neuro MD