OCCIPITAL LOBE EPILEPSY IN CHILDREN: THE CLINICAL SPECTRUM AND OUTCOME

Objectives: To describe the electroclinical features and outcome in children with occipital lobe epilepsy.

Methods: The medical records of children identified from an Epilepsy and EEG Data base were retrospectively reviewed. A diagnosis of occipital lobe epilepsy was based on seizure semiology, interictal and ictal EEG and/or an occipital lobe abnormality on neuroimaging.

Results: The study population comprised 42 children, 24 females and 18 males. Age at seizure onset was 1 day to 15 years. Seizure types were simple partial (17), complex partial (28) and secondarily generalized seizures (19). Four patients had infantile spasms, 6 febrile seizures and 5 status epilepticus. A family history of epilepsy occurred in 13 (30%) and migraine in 45%. Auras were reported in 24 (57%), visual loss (12), flashing lights (7), colours (3), formed visual hallucinations (2), vertigo (5) and nausea (2), >1 aura was reported in some. Headache occurred ictally in 3, post-ictally in 16 and 18 (43%) had interictal migraine. An etiology was demonstrated in 22 (52%) malformations of cortical development (8), infarction (6), infectious/inflammatory (3), tumors (2) and other (3). A diagnosis of benign occipital lobe epilepsy was made in 13. Bilateral occipital or posterior quadrant delta occurred in 23, unilateral delta in 9, unilateral occipital or posterior quadrant epileptiform discharges in 19 and bilateral in 15. Generalized spike and wave occurred in 6. Seizures were recorded in 17 patients. At most recent follow-up (1 to 10 years), 16 patients were seizure free for >1 year. 11 were on no AEDs.

Conclusion: Symptomatic occipital lobe epilepsy was more common than benign occipital lobe epilepsy in this population. The most common aura was visual loss. Bilateral occipital or posterior hemisphere slowing and spikes were common.