Selective reduction of the S-cone component of the electroretinogram in Posner-Schlossman syndrome.
OBJECTIVE
The changes in short wavelength sensitive (S-) cone electroretinograms (ERGs) to ganzfeldt flash stimuli were examined in patients with Posner-Schlossman syndrome to study the differences in S-cone action in both the acute attack phase and the remission phase.


METHODS
Ganzfeldt colour flashes under bright white background illumination were used to elicit short wavelength (S-), and mixed long- (L) and middle- (M) wavelength sensitive cone ERGs. Three subjects with unilateral Posner-Schlossman syndrome and 18 age-matched normal controls were compared. To compare the media opacity we obtained the L,M-cone balance, namely, the log density units of the neutral density filter required to produce the L,M-cone b-wave elicited with red stimuli which is identical to those with blue stimuli.


RESULTS
Selective reduction of the S-cone ERG b-wave in acute attacks of Posner-Schlossman syndrome was found. Two of three cases showed the recovery of the S-cone b-wave with a decrease in the intraocular pressure. With regard to the implicit time, significant delay of the S-cone b-wave could not be detected in all subjects.


CONCLUSIONS
Selective reduction of the S-cone component of the ERG during raised intraocular pressure was found. The S-cone pathway is thought to be more vulnerable to damage than the L,M-cone systems following elevations of intraocular pressure.
Maeda
H
H
Department of Ophthalmology, Kobe University, Japan. hidetaka@med.kobe-u.ac.jp
Nakamura
M
M
Negi
A
A
D000208:Acute Disease; D000328:Adult; D002924:Ciliary Body; D004596:Electroretinography; D005901:Glaucoma / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017949:Retinal Cone Photoreceptor Cells / Q000503:physiopathology*; D013577:Syndrome; D014605:Uveitis / Q000503:physiopathology*