CHANGES IN CEREBRAL BLOOD-FLOW VELOCITIES ASSOCIATED WITH RADERMECKERCOMPLEXES IN A PATIENT WITH SUBACUTE SCLEROSING PANENCEPHALITIS - A CASE-REPORT

The electroencephalogram (EEG) in subacute sclerosing panencephalitis (SSPE) is characterized by generalized periodic high amplitude complex es recurring at intervals of 4-12 seconds (Radermecker complexes). Lit tle is known about their genesis, although most authors favor a brain stem origin. We wished to study changes in cerebral perfusion associat ed with these complexes in order to better understand their pathophysi ology. We present a 15-year old girl who was diagnosed to have SSPE wi th cognitive and intellectual decline. Radermecker complexes were firs t detected on EEG after an injection of midazolam. They occurred spont aneously 2 weeks later. We studied changes in cerebral blood flow velo cities (CBFV) measured by transcranial Doppler (TCD) in both middle ce rebral arteries (MCA) time-locked to the occurrence of the Radermecker complexes. Averaging 250 Radermecker complexes over five recording se ssions demonstrated a biphasic signal with a decrease in CBFV by 5.8%, peaking at 0.7 seconds after the onset of the complexes, and a subseq uent increase in CBFV by 3.7% peaking at 3 seconds after the be,inning of the complex. Changes in heart beat showed a similar course with an initial decrease and a subsequent increase in frequency. These simila r temporal changes between CBFV and heart rate suggest that the pathop hysiologic mechanisms of these complexes may also affect the balance o f autonomic tone descending from brain to heart. (C) 1998 by Elsevier Science Inc. All rights reserved.