Visual evoked potentials after panretinal photocoagulation in patients with proliferative diabetic retinopathy

Abstract

Purpose

To evaluate the changes of latency and amplitudes of pattern-reversal visual evoked potentials (PRVEP) in patients with proliferative diabetic retinopathy after panretinal photocoagulation (PRP).

Methods

PRVEP was recorded in 21 eyes of 21 patients with proliferative diabetic retinopathy prior to, 1 week after every sessions of laser therapy and 1.5 months after the final treatment. Results were compared between pre and post laser treatment sessions in the study group and paired t-test was used for statistical analysis.

Results

The P100 amplitude showed a significant difference among all treatment sessions with a decreasing trend in the study group after PRP (P<0.001). Also, P100 latency evaluation showed a significant increase after PRP in the study group in all post-PRP sessions (P<0.05). However, 1.5 months after laser treatment, an increase in amplitudes (P<0.001) and a decrease in latencies (P<0.001) of PRVEP were observed and the magnitudes of the parameters approximately returned to their baseline values.

Conclusion

Although decreasing changes in the amplitude and increasing changes in the latency of PRVEP were observed after laser treatment in proliferative diabetic retinopathy patients, one and a half months after the completion of laser therapy, partial recovery of these parameters values was observed.

Keywords:

• photocoagulation
• visual evoked potential
• proliferative diabetic retinopathy

Consent for publication

Written informed consents was obtained to publish the details from each participant.

Ethics approval and informed consent

The study protocol adhered to the tenets of the Declaration of Helsinki and was approved by the institutional review board of the Iran University of Medical Sciences, the Steering Committees of the School of Rehabilitation Sciences and Farabi Eye Hospital of the Tehran University of Medical Sciences. All patients signed a written informed consent form to allow the evaluation of their clinical data.

Acknowledgment

The authors have no financial interest in any of the products mentioned in the manuscript. The authors would like to extend their sincere appreciation to Frabai eye hospital staff for their assistance and co‐operation in carrying out the electrophysiological tests by MonPack3 system. This study was part of a Masters thesis supported by the Tehran University of Medical Sciences (grant No:91/01/6931).

Disclosure

The authors report no conflicts of interest in this work.