doi:10.1684/epd.2018.0994 434 Epileptic Disord, Vol. 20, No. 5, October 2018 Correspondence: Pablo Gómez-Porro Sánchez Panamá 4 1 ◦ b. 28220, Majadahonda, Madrid, Spain <gomezporrosanchez@gmail.com> Clinical commentary Epileptic Disord 2018; 20 (5): 434-9 Genetic (idiopathic) generalized epilepsy with occipital semiology Pablo Gómez-Porro 1,2 , Angel Aledo Serrano 1 , Rafael Toledano 1 , Irene García-Morales 1 , Antonio Gil-Nagel 1 1 Hospital Ruber Internacional, Madrid 2 Hospital Universitario Puerta de Hierro, Madrid, Spain Received August 21, 2017; Accepted June 09, 2018 ABSTRACT – Idiopathic photosensitive occipital lobe epilepsy (IPOE) is a syndrome that should be suspected in patients with seizures with occipi- tal semiology, photosensitivity, and normal MRI. It should be distinguished from occipital epilepsy of unknown aetiology (cryptogenic) given the differ- ences in management. We reviewed patients with occipital seizures which were investigated in our epilepsy unit during the last three years. Three patients were identified with features of IPOE and genetic generalized epilepsy (GGE), formerly known as idiopathic generalized epilepsy, and their clinical characteristics were analysed. We propose the term “idiopathic generalized epilepsy with occipital semiology” based on the significance of managing and treating this syndrome as a GGE. Key words: genetic epilepsy, visual, photosensitivity, light, idiopathic, occipital epilepsy Differential diagnosis between occipital cryptogenic epilepsy (OCE) and idiopathic photosensi- tive occipital lobe epilepsy (IPOE) is often difficult. These two epilep- sies are usually considered in the presence of spontaneous or light- induced seizures with occipital semiology, with normal neuro- logical examination and normal brain MRI. IPOE was first described in 1995 by Guerrini et al. (1995) who reported 10 patients with a pure phenotype and presentation of reflex occipital seizures exclu- sively. Subsequently, other groups reported similar cases, broadening the clinical spectrum to include also spontaneous occipital seizures, leading to the recognition that IPOE could be a syndrome with no well-defined boundaries. Fur- ther support to the existence of a form of genetic generalized epilepsy (GGE) with occipital lobe semi- ology was presented by Taylor et al. (2004) who described three patients with myoclonic juvenile epilepsy, also presenting with visual auras. In addition, these authors described four families whose members suffered from epilepsy with both GGE and IPOE features.