Visually induced epilepsies
Imad Yassin Saadeldin
Last modified: 2014-04-03
Abstract
Background/objectives:
The aim of the study was to define the spectrum of the epileptic syndromes and epilepsies that can be associated with fixation-off sensitivity (FOS) and delineate the electro-clinical types of FOS.
Design and methods:
Clinical and video EEG data of all our patients with FOS over the last 6 years were reviewed using FOS technique described by Panayiotopoulos.
Results:
The results show that from January 2005 to December 2012, 14 of about 1,990 patients had had one or more video-EEGs with FOS (0.70%). From the 14 patients with full clinical and EEG data available, 8 had various epilepsies that included: symptomatic or probably symptomatic focal (8), cryptogenic generalized (4), and two had no seizures. Four patients (28%) were photosensitive of which a twin with Jeavons syndrome and one was scotosensitive. FOS EEG abnormalities were occipital in 6 patients, and generalized in two.
Two showed atypical forms. One boy of normal intelligence showed abnormal behavior associated with disorientation and confusion and postictal amnesia. His video/EEG evaluation unexpectedly documented the presence of FOS. Another patient was diagnosed with atypical benign partial epilepsy, and his repeated video/EEG recordings showed FOS. His sister was diagnosed with epileptic encephalopathy with continuous spike and wave complexes. Four patients were diagnosed as childhood absence epilepsy.
Conclusions:
Irrespective of classification, routine video-EEG monitoring for documenting FOS suggested by Panayiotopoulos should be offered to selected patients with epilepsy. Unusual and rare cases within the spectrum of benign childhood seizure susceptibility syndrome can explain the atypical cases.
Keywords
Fixation-off sensitivity; video/EEG; Epilepsy; Panayiotopoulos.
References
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