OBSERVATIONS IN PHOTOSENSITIVE CHILDREN WITH AND WITHOUT EPILEPSY

The course of convulsive disease in 195 photosensitive children was analysed. Of these, 168 were suffering from cerebral seizures and 27 from various other disorders. Only four of the patients occasionally exhibited photogenic seizures. In all the other cases the cerebral seizures occurred independently of intermittent light stimuli. 1. The clinical picture of photosensitive epilepsy varies widely. Virtually all known forms of seizures and courses of illness may be seen. In the group investigated, febrile and afebrile grand mal attacks predominated. Focal seizures and petit mal followed in third and fourth place respectively. 2. Photosensitive epilepsies are more common in females than in males. 3. The course of photosensitive epilepsy is often highly malignant. This applies especially when focal symptoms are present and when the onset of the disease took place after the fifth year of life. 4. A total of 67 per cent of the patients first suffered seizures before the sixth year of life, i.e. before the age of maximum penetrance of photosensitivity. 5. Investigation of the family histories of the patients indicated that the appearance of the disease in early childhood was affected by additional genetic factors, probably independent of photosensitivity itself. 6. Photosensitivity is to be regarded as a symptom of a gene-dependent functional disorder. The activability of this via optic afferents is markedly age-linked. © 1969 Springer-Verlag.