Reproducibility of Fixed-luminance and Multi-luminance Flicker Electroretinography in Patients With Diabetic Retinopathy Using an Office-based Testing Paradigm

Retinal Toxicity Assessment Following Vitreoretinal Surgery: A Comparison of Silicone Oil and Perfluoropropane Tamponade Using Diopsys® NOVA™

PURPOSE

This study aimed to assess and compare the retinal toxicity associated with silicone oil (SO) and perfluoropropane (C3F8) tamponade following vitreoretinal surgery for fresh rhegmatogenous retinal detachment (RRD), utilizing the office-based Diopsys® NOVA™ system for evaluation.

METHODS

Patients who underwent vitreoretinal surgery for fresh RRD and had SO (group 1) or C3F8 (group 2) tamponade were included in a prospective analysis. Flicker full field electroretinography (ffERG) and pattern electroretinography (PERG) tests were performed at 6 months postoperatively.

RESULTS

Postoperative best corrected visual acuity (logMAR) was significantly different in group 1 and group 2 patients, 0.48 ± 0.3 and 0.30 ± 0.2, respectively. No significant disparities were found in demographic variables. Flicker ffERG and PERG recordings revealed notable alterations in retinal function parameters in the group 1 compared to the group 2.

CONCLUSION

Our findings suggest a correlation between SO tamponade and retinal dysfunction, evidenced by office-based ERG measurements. The Diopsys® NOVA™ protocol offers clinical ease in assessing retinal function. Further controlled studies are essential to validate these findings and guide clinical practice effectively.

International Olympic Committee (IOC) consensus paper on sports-related ophthalmology issues in elite sports

Vision plays an important role in an athletes' success. In sports, nearly 80% of perceptual input is visual, and eye health and sports medicine are closely intertwined fields of utmost importance to athletes. The physical nature of sports activities renders individuals more prone to various eye injuries than the general population. Ocular trauma can lead to lifelong sequelae, and impaired vision requires careful follow-up and management. Apart from injuries, athletes may also experience vision problems that can hamper their performance, including blurred vision, double vision, and light sensitivity. The interdisciplinary nature of sports medicine necessitates collaboration between sports medicine professionals and ophthalmologists. Through such collaborations, athletes can receive appropriate eye care, education on proper eye protection and guidance on adopting good eye health practices. If any inconspicuous symptoms are not detected and treated promptly, athletes may acquire systemic injuries because of defective vision, preventing them from achieving high level athletic performance in competitions. The protection of the elite athlete is the responsibility of all of us in sports medicine. To advance a more unified, evidence-informed approach to ophthalmic health assessment and management in athletes and as relevant for sports medicine physicians, the International Olympic Committee Consensus Group aims for a critical evaluation of the current state of the science and practice of ophthalmologic issues and illness in high-level sports, and present recommendations for a unified approach to this important issue.

Evaluation of correlation between Diopsys® NOVA™ fixed-luminance flicker ERG and Diagnosys® Espion 2™ flicker ERG parameters

PURPOSE

Diopsys® NOVA™ is a novel full-field electroretinography (ffERG) device that can make rapid measurements of retinal electrophysiologic function. Diagnosys® Espion 2™ is a clinical gold-standard ERG device. This study aimed to investigate whether light-adapted Diopsys® NOVA™ fixed-luminance flicker ffERG magnitude and implicit time (converted from phase) measurements correlate with light-adapted Diagnosys® Espion 2™ flicker ffERG amplitude and implicit time measurements, respectively.

METHODS

Twelve patients (22 eyes) with various retinal and uveitic diseases underwent light-adapted Diagnosys® Espion 2™ and Diopsys® NOVA™ fixed-luminance flicker testing. Diopsys® magnitude and implicit time (converted from phase) measurements were compared to Diagnosys® amplitude and implicit time measurements, and a Pearson correlation was used to evaluate any existing correlation. Groups were also compared using generalized estimating equations. Bland-Altman plots were utilized to determine agreement between the comparison groups.

RESULTS

Age of patients ranged from 14 to 87 years. 58% (n = 7/12) of patients were female. A significant, positive correlation (r = 0.880, P < 0.001) was observed between magnitude (Diopsys®) and amplitude (Diagnosys®) measurements. Amplitude increases by 6.69 µV for each 1 µV increase in Magnitude (p-value < 0.001). A statistically significant, strong positive correlation was observed between Diopsys® implicit time measurements (converted from phase) and Diagnosys® implicit time measurements (r = 0.814, p-value < 0.001). For each 1 ms increase in Diopsys® implicit time, Diagnosys® implicit time increases by 1.13 ms (p-value < 0.001).

CONCLUSIONS

There is a statistically significant positive correlation between light-adapted Diopsys® NOVA™ fixed-luminance flicker amplitude and Diagnosys® flicker magnitude values. Additionally, there is a statistically significant positive correlation between Diopsys® NOVA™ fixed-luminance flicker implicit time (converted from phase) and Diagnosys® flicker implicit time values. These results imply that the Diopsys® NOVA™ module, which utilizes the nonstandard shortened International Society for Clinical Electrophysiology of Vision (ISCEV) ERG protocol, can produce reliable light-adapted flicker ffERG measurements.

Effect of Pupil Size on Fixed-Luminance Flicker Full-Field Electroretinogram Magnitude

Purpose

Diopsys^® NOVA fixed-luminance flicker full-field electroretinogram (ffERG) device is a potential adjunct to conventional flicker ffERG testing for assessing cone cell function. Magnitude of measured electrical response is known to vary with pupil size in conventional ffERG testing. The index study characterizes the relationship between magnitude of measured electrical activity and pupil size, both pupil diameter and pupil area, for this device.

Methods

Seventeen patients (34 eyes) with no known ocular diseases were enrolled in the study. Electrophysiologic function of cone cells was evaluated using fixed-luminance flicker ffERG before and after dilation. Linear regression models, with inter-eye correlations controlled as fixed-effects, were used to characterize the effect of pupil dilation on the magnitude of the measured responses.

Results

Mean age of study patients was 33.5 (standard deviation 7.4 years), and 35.3% of the subjects were female. Mean value of electrical response magnitude was 10.07±2.79µV before dilation and 15.30±4.08µV after dilation. The correlations of ERG magnitude with pupil diameter and with pupil area were not significant for either dilated or undilated eyes considered separately but were highly significant (p<0.001) for dilated and undilated eyes considered in aggregate. ERG magnitude tended to increase by 1.08 µV for every 1 mm increase in pupillary diameter.

Conclusion

An increase in pupil size, both pupil diameter and pupil area, is significantly associated with an increase in flicker ffERG magnitude recorded by the Diopsys device, suggesting that pupil size should be measured and considered when making clinical judgments based on the flicker ffERGs recorded by the device, and that pupil size-specific reference ranges could improve the clinical utility of the device.

Fixed-Luminance and Multi-Luminance Flicker Electroretinography Parameters in Patients with Early Active Birdshot Chorioretinopathy

Purpose To evaluate the parameters of the Fixed-Luminance and Multi-Luminance flicker electroretinography protocol among patients with early active birdshot chorioretinopathy.Methods Fixed-Luminance magnitude, Fixed-Luminance phase, Multi-Luminance magnitude area under the curve, and Multi-Luminance phase area under the curve parameters were compared between early active birdshot chorioretinopathy patients and an age-matched control group.Results There was no statistically significant difference between the Fixed-Luminance flicker magnitude (P = .6), the Fixed-Luminance flicker phase (P = .9), and the Multi-Luminance flicker phase area under the curve (P = .55) when each was compared to the normal population; however, the difference between the mean Multi-Luminance flicker magnitude area under the curve in our patients and the healthy control group was statistically significant. (P = .003)Conclusions Multi-Luminance flicker magnitude area under the curve has been shown to be significantly different from the normal population in the early active course of the disease.Abbreviations BSCR: birdshot chorioretinopathy; cd: Cadmium; ERG: Electroretinography; FA: Fluorescein angiography; FL-: Fixed-luminance; HVF: Humphrey visual field; Hz: Hertz; ICG: Indocyanine green; m²: Square meter; ML-: Multi-luminance; ms: millisecond; SITA: Swedish interactive thresholding algorithm; SWAP: Short wave-length automated perimetry.