Suppressive Efficacy by a Commercially Available Blue Lens on PPR in 610 Photosensitive Epilepsy Patients

Abstract

Summary:Purpose: Photosensitivity can represent a serious problem in epilepsy patients, also because pharmacologic treatment is often ineffective. Nonpharmacologic treatment using blue sunglasses is effective and safe in controlling photosensitivity, but large series of patients have never been studied.Methods: This multicenter study was conducted in 12 epilepsy centers in northern, central, southern, and insular Italy. A commercially available lens, named Z1, obtained in a previous trial, was used to test consecutively enrolled pediatric and adult epilepsy patients with photosensitivity. Only type 4 photosensitivity (photoparoxysmal response, PPR) was considered in the study. A standardized method was used for photostimulation.Results: Six hundred ten epilepsy patients were tested. Four hundred (66%) were female patients; 396 (65%) were younger than 14 years. Three hundred eighty-one (62%) subjects were pharmacologically treated at the time of investigation. Z1 lenses made PPR disappear in 463 (75.9%) patients, and PPR was considerably reduced in an additional 109 (17.9%) of them. PPR remained unchanged only in the remaining 38 (6.2%) patients. The response of PPR to Z1 lenses was not significantly influenced by the patients' age, sex, or type of epilepsy. No difference was found between pharmacologically treated and untreated patients.Conclusions: The Z1 lens is highly effective in controlling PPR in a very large number of photosensitive epilepsy patients irrespective of their epilepsy or antiepileptic drug treatment. The lens might become a valid resource in the daily activity of any clinician who cares for patients with epilepsy.

Reexamining the Added Value of Intermittent Photic Stimulation and Hyperventilation in Routine EEG Practice

“…Besides its importance in increasing the diagnostic yield of routine EEG and better defining the type of epilepsy, IPS has other potential benefits that were not specifically addressed in this study [3]. Quantification of the response to IPS by determining the flash frequency thresholds eliciting a PPR and personalized studies using pattern and TV testing can help identify environmental triggers [19] and, accordingly, select the most appropriate therapeutic measure [20]. …”

Methodology of photic stimulation revisited: Updated European algorithm for visual stimulation in the EEG laboratory

“… Quantification of the response to IPS (upper and lower flash frequency thresholds eliciting a PPR) and tailored studies with pattern and TV testing can help in advising lifestyle restraints (video games, disco lights, TV programs, and so on) (Rubboli et al., 2004) and in choice and evaluation of treatment. Prescription of blue‐colored glasses (Capovilla et al., 2006) are useful in a variety of clinical situations, for example, in pregnancy, to avoid antiepileptic therapy or polytherapy. There are, however, indications that the colors selected individually to reduce visual discomfort may offer an effective alternative in patients who do not respond to blue lenses or who do not accept them (Wilkins et al., 1999).…”

Ictal Headache and Visual Sensitivity

“…During intermittent photic stimulation (IPS) generalized polyspikes and waves of 2 s duration could be evoked between 12 and 26 Hz, with subtle clinical signs when the discharges outlasted the stimulus train (spontaneous opening of the eyes at 24 Hz and ocular discomfort at 22 Hz). Prophylactic treatment was started with blue lenses (20).…”