Role of Electroencephalography in Diagnosis of NCL۲

Electroencephalographic (EEG) characteristics of neuronal ceroid lipofuscinosis type ۲ (CLN۲) disease might be help to diagnosis of this rare epileptic encephalopathy fromother encephalopathies in children. The purpose of the current paper is to review conducted studies the association of photosensivity in the NCL۲. These EEG features arecalled photo paroxysmal response(PPR), initially reported by Pampiglione et al, are not specific for NCLs but there are some features for PPR that are specific for CLN۲ disease. The PPR is spike-wave response that is time locked to the photic stimulation at lowfrequency IPS(۱–۳Hz). It might be beneficial if PPR could be used as a marker for NCLs because EEGs are done for all patients who present with seizures but other tests (e.g, electroretinography, visual evoked potential) are not performed except patients that they are suspected to NCLs. According to the previous study and case reports photosensitivity with low stimulation frequencies (۱–۳ Hz) is a hallmark of CLN۲ disease. This diagnosis should be considered in a child presenting with any type of seizure.

Keywords:

NCL , Epilpsy , Children , PPR , EEG.