Clinical characteristics, seizure spread patterns and prognosis of seizures associated with a single small cerebral calcific CT lesion.

Clinical characteristics of 97 patients with epilepsy associated with a small single cerebral calcific CT lesion (SSCCCTL), measuring 20 mm or less were analysed. The mean age was 20 years and 60% were in the first and second decades. Eighteen (18.5%) patients had a previous history of unprovoked seizures, with complex partial seizures (61%) being the most common type. Seizures could be localized to a single ILAE site in 73% of patients. None had neurological deficit and electroencephalograph abnormalities were noted in 29% of patients. Fifty-one (53%) patients had breakthrough seizures and were more common with frontal location. By 7 years 71.5% (95% confidence intervals (CI) 53.7-85.4) of patients achieved 3-year remission and 66% (CI 32.4-88.2) had achieved 5-year remission. The clinical pattern of the seizures was clearly distinctive to allow it to be localized to the location of the lesion on computerized tomography (CT) scan in 25 (26%) patients and in another 31 (31%) patients nearer to the anatomical site of the lesion on the CT scan. There was discordance between clinical localization and CT location of the lesion in 15 patients. Nine of the 10 patients with occipital or parieto-occipital location had focal tonic-clonic seizures with secondary generalization. Both patients with temporal location had motor seizures. The relevance of these findings to the seizure propagation was discussed.