A Prolonged Rhythmic Midtemporal Discharge in a Child Without Seizures

Rhythmic midtemporal discharge (RMTD) is one of the benign epileptiform variants, typically consisting of runs of 4-Hz to 7-Hz activity, lasting up to 10 seconds and maximal over the midtemporal area. We report a child who, during an admission for diagnostic closed-circuit television (CCTV) and electroencephalographic (EEG) monitoring, was found to have prolonged rhythmic monomorphic discharges, alternating over both midtemporal areas, with one of the discharges lasting up to 82 minutes. An analysis of the dominant frequency, during the longest discharge, showed that it was monomorphic throughout. On the basis of various features of these discharges, we concluded that they represented RMTD of unusual duration.