Inner retinal visual dysfunction is a sensitive marker of non-proliferative diabetic retinopathy
- 1Penn State Hershey Eye Center, Penn State College of Medicine, Hershey, Pennsylvania, USA
- 2Kellogg Eye Institute, University of Michigan, Ann Arbor, Michigan, USA
- Correspondence to Dr Gregory R Jackson, 500 University Drive, HU19, Penn State College of Medicine, Hershey, PA 17033, USA;
Contributors GRJ designed and instrumented the study, conducted the data analysis and was the primary author of the manuscript. IUS, DAQ and TWG participated in the design of the study, recruited patients and edited the manuscript to provide their clinical insights. LEW aided in instrumentation of the study, recruitment, conducted all data collection, data entry and assisted in editing the manuscript.
- Accepted 12 November 2011
- Published Online First 15 December 2011
Aims To determine the effect of diabetes on inner and outer retinal function in persons with diabetes and no clinically detectable retinopathy or with non-proliferative diabetic retinopathy (NPDR).
Methods Visual function was assessed in 18 adults with normal retinal health, 23 adults with diabetes and 35 adults with NPDR and normal visual acuity. Contrast sensitivity and frequency doubling technology (FDT) sensitivity were used to assess ganglion cell function. Acuity, dark adaptation, light-adapted visual sensitivity and dark-adapted visual sensitivity were measured to evaluate cone and rod photoreceptor visual function. The presence and severity of diabetic retinopathy was determined by grading of 7-field stereoscopic fundus photographs using the Early Treatment Diabetic Retinopathy Study grading system.
Results Participants with NPDR exhibited impairment of all measured visual functions in comparison with the normal participants. Inner retinal function measured by FDT perimetry was the most impaired visual function for patients with NPDR, with 83% of patients exhibiting clinically significant impairment. Rod photoreceptor function was grossly impaired, with almost half of the patients with NPDR exhibiting significantly impaired dark-adapted visual sensitivity.
Conclusion Both inner retinal and outer retinal functions exhibited impairment related to NPDR. FDT perimetry and other visual function tests reveal an expanded range of diabetes induced retinal damage even in patients with good visual acuity.
Funding This study was supported by the JDRF Diabetic Retinopathy Center at the Penn State College of Medicine, Pennsylvania, USA. DAQ is the George and Barbara Blankenship Professor.
Competing interests GRJ is an employee and investor in Apeliotus Vision Science, the manufacturer of the AdaptRx. The authors are solely responsible for the content of the manuscript.
Patient consent Obtained.
Ethics approval Ethics approval was provided by Penn State Hershey Institutional Review Board.
Provenance and peer review Not commissioned; externally peer reviewed.