ABSTRACT
We studied data on seizures, vacant spells and breathing dysrhythmia from the British Rett Survey and 150 electroencephalographic records from 78 classic cases, including 23 with prolonged synchronous recordings of EEG, respiration and movement. The proportion of abnormal records increased from 6 of 18 (33%) during the first 6 months of the regression period to 44 of 59 (75%) in the later period to 6 years, the increase in abnormality following rather than preceding the onset of regression. In young girls the EEG abnormality increased in sleep but decreased during episodic hyperventilation and breath-holding. Epileptogenic activity was commonly present without clinical seizures. Eleven vacant spells were monitored and were not epileptic but related to the breathing abnormality. Full monitoring is essential when supposed seizures are intractable. The intermittent EEG abnormality and behavioural changes indicate abnormal fluctuating arousal possibly of midbrain or brainstem origin.
Subject(s)
Electroencephalography , Rett Syndrome/diagnosis , Rett Syndrome/therapy , Videotape Recording , Adolescent , Adult , Brain Stem/physiopathology , Child , Child, Preschool , Diagnosis, Differential , Female , Humans , Hyperventilation/diagnosis , Mesencephalon/physiopathology , Middle Aged , Respiration Disorders/diagnosis , Seizures/diagnosis , Seizures/physiopathology , Severity of Illness Index , Sleep, REM/physiology , Surveys and QuestionnairesABSTRACT
A system is described by means of which the ambulant subject may be video-filmed over several hours with the electroencephalograph superimposed on the same tape, allowing correlations to be observed in the active state. Our first subjects have been girls with Rett syndrome. Requirements are: one portable video camera/recorder, a conventional e.e.g. machine, the 'Medilog 9000' system for prolonged ambulatory recording (Oxford Medical), a specialized video mixer (videogram ForA FVG600, commercially available) a video timer, a conventional video cassette recorder and a television monitor. The cost is small for a department already equipped to carry out ordinary ambulatory e.e.g. monitoring. The method is safe, well tolerated, simple to use and adaptable. To the best of the authors' knowledge, they are the first to use this system and they believe that it should find wider application when it is desirable to correlate the behaviour of a subject with physiological parameters, on a restricted budget.