[Macular morphology and function in patients with diabetic retinopathy without apparent visual loss.]
ABSTRACT PURPOSE: To investigate the macular morphology and function in patients with diabetic retinopathy(DR) without apparent visual loss. METHODS: Multifocal electroretinograms(mfERG) and optical coherence tomography(OCT) examination were performed in the DR patients on phase 0, 1 to 2, 3 to 4 as well as the normal control non-diabetes subjects. RESULTS: Macular edema was detected in DR phase 1 and 2 (3 eyes,10%) and DR phase 3 and 4 group (6 eyes,23.1%). In comparison with the normal control and DR phase 0 group,the thickness of retinal neuroepithelium increased in DR phase 3 and 4 group(P>0.05). The amplitude and the average density of P1 wave and N1 wave decreased in all DR groups in comparison with normal controls although the latency of P1 wave and N1 wave was not statistically significant (P>0.05).However,comparing with the DR phase 1 and 2 group,the latency of P1 wave and N1 waves were longer whereas the amplitude and the average density decreased in DR phase 3 and 4 group. CONCLUSION: In the patients with DR but without apparent visual loss,abnormalities of the macular morphology and function already develop. The changes of function appear to develop earlier than that of morphology.