This article is more than 5 years old. Information may no longer be current.
Electrically stimulated phosphene thresholds may help monitor retinal disease progression
Click Here to Manage Email Alerts
Electrically evoked phosphene thresholds may aid in the explanation of various ophthalmic disease progression, according to a study.
The study included 117 eyes in 117 individuals. Twenty subjects were healthy controls, 30 patients had retinitis pigmentosa, 20 had retinal artery occlusion, 17 had primary open angle glaucoma (POAG), 16 had nonarteritic anterior ischemic optic neuropathy (NAION), and 14 had Stargardt’s disease.
Electrically evoked phosphene thresholds (EPT) were evaluated in all patients at 3, 6, 9, 20, 40, 60 and 80 Hz. Across all frequencies, EPTs were significantly higher in patients with retinal diseases, except Stargardt’s disease, than in healthy patients.
At 20 Hz, EPTs were 0.062 ± 0.038 mA for healthy subjects, 0.102 ± 0.097 mA for Stargardt’s disease, 0.127 ± 0.09 mA for POAG, 0.244 ± 0.126 mA for NAION, 0.371 ± 0.223 for retinitis pigmentosa and 0.988 ± 1.142 mA for retinal artery occlusion. EPTs were lowest at 20 Hz in all patients.
“Determination of EPTs could be potentially useful in elucidation of the progress of ophthalmologic diseases, either in addition to standard clinical assessment or under conditions in which these standard tests cannot be used meaningfully,” the study authors said.
Click Here to Manage Email Alerts