Patients with epilepsy often undergo evaluation by concurrent video and EEG monitoring (vEEG) for therapeutic planning, including possible epilepsy surgery. Seizures during monitoring increase the diagnostic yield and requires the withdrawal of anticonvulsant drugs (AEDs) to allow seizures to occur. A frequently asked question in clinical practice concerns the safety and long-term effect of AED withdrawal or discontinuation in this diagnostic procedure.
To answer this question, investigators at the University of Saskatchewan in Canada, conducted a prospective study of 150 patients admitted to their vEEG telemetry unit over a period of five years. The patients' medication therapy was discontinued by a standardized rapid AED withdrawal protocol. Rapid discontinuation was not done in patients with a previous history of status epilepticus or taking phenobarbital. The researchers then assessed the number of patients having subsequent seizures, the safety of the withdrawal/ telemetry procedure, and epilepsy surgery outcome.
Seizures and non-epileptic events were recorded in nearly 90% of the patients. This diagnostic yield was achieved over a mean VEM duration of 4.53 days, with no benefit of longer monitoring. Habitual seizures were recorded in 107 patients to support a diagnosis of epilepsy while non-epileptic events were recorded in 36 patients.
Based on the information provided by vEEG telemetry, 52 of 158 patients (32.9%) received epilepsy surgery of which nearly 90% attained Engel Class I/II status at 24 months. The complication rate was 5.06%, characterized largely by musculoskeletal pain secondary to clinical seizure activity, with no mortality observed. In the first month following VEM 2.5% of patients received emergency-room admission for seizure clustering.
"VEEG telemetry monitoring with early cessation of AED therapy is safe and effective," says Syed A. RIzvi, MD, lead author of the report, "Surgical outcomes are favorable and support the use of this technique under the supervision of a team comprising epileptologists, nurses, and EEG technologists."
Cite This Page: