Junya Kizawa | PubMed Health

PubMed2004

Decrease of blue cone sensitivity in acute idiopathic blind spot enlargement syndrome.

PURPOSE: To determine the sensitivity of the blue cone system by static perimetry in patients with unilateral acute idiopathic blind spot enlargement (AIBSE) syndrome. DESIGN: Observational case series. METHODS: Four patients with AIBSE syndrome, aged 16 to 30 years, were studied. Diagnosis of the AIBSE syndrome was based on clinical findings including an enlarged blind spot without corresponding ophthalmoscopic changes of the ocular fundus and with depressed multifocal electoretinograms. The visual sensitivity and mean deviations (MD) were measured by white-on-white (W/W) and blue-on-yellow (B/Y) automated perimetry. RESULTS: The average difference in the MD between the affected and unaffected eyes was 4.87 +/- 1.51 dB and 13.65 +/- 4.19 dB for W/W and B/Y perimetries, respectively. The difference between the two groups of eyes was significantly greater for B/Y perimetry than that for W/W perimetry (P =.01). CONCLUSIONS: Our results suggest that the decrease of blue cone sensitivity is diffusely present over the retina in eyes with AIBSE syndrome. We recommend B/Y perimetry as a sensitive measure to detect retinal dysfunction that is not detected by W/W perimetry.

Acute Disease↗

PubMedDate not supplied

Changes of oscillatory potentials and photopic negative response in patients with early diabetic retinopathy.

PURPOSE: To investigate the clinical significance of the oscillatory potentials (OPs) and photopic negative response (PhNR) of the electroretinogram (ERG) in patients with early diabetic retinopathy. METHODS: One hundred two diabetic patients with diabetic retinopathy at different stages were examined. Thirty-two age-matched normal controls were also studied. Full-field maximal and photopic cone ERGs were recorded. The amplitudes and implicit times of the OPs, cone b wave, and PhNR were compared at the different stages of diabetic retinopathy. RESULTS: The a and b wave amplitudes of the maximal scotopic ERGs remained unchanged despite advancing stages of retinopathy, but the OP amplitudes were significantly attenuated even at an early stage of diabetic retinopathy. The amplitudes of both the PhNR and cone b wave were reduced at an early stage of diabetic retinopathy. Analysis of the receiver operating characteristic curves demonstrated that the amplitudes and implicit times of the OPs were more sensitive and specific than those of the PhNR in detecting changes of retinal function in the early stages of diabetic retinopathy. CONCLUSIONS: The amplitudes of the OPs and PhNR progressively decrease with the progression of diabetic retinopathy. The PhNR amplitudes were reduced along with the cone b wave, indicating that earlier change of the PhNR in diabetic patients reflects reduced input to the retinal ganglion cell from the distal retina. The amplitudes and implicit times of the OPs are better indicators than those of the PhNR in detecting functional decreases in patients with early diabetic retinopathy.

Action Potentials↗