Diagnostic power of rapid objective perimetry in young people with Type 1 Diabetes

Abstract

Purpose : To examine the diagnostic power of 4^th and 5^th generation (4G and 5G) objective perimetry stimuli in young people with Type 1 Diabetes (T1D) but no retinopathy.

Methods : We examined 52 young persons with T1D (15.2 ± 3.77 y, 26 females), and 29 normal subjects (16.2 ± 3.65 y, 13 females) with two 5G stimulus methods of the ObjectiveFIELD Analyser (OFA): M18 and W20, which test both eyes in 82 seconds. M18 and W20 test 18 and 20 regions/field spanning the central 20 and 60 deg. These were compared with a 4G stimulus, P131 testing 44 regions of the central 30 deg in 7 minutes. We examined diagnostic power of Total deviations (TDs) and pattern deviations (PDs) based upon Sensitivities, Delays, and linear combination scores. We then assessed diagnostic power as area under receiver operator characteristic plots (AUROC). ROC analysis was repeated for subjects <16 y (25 T1D, 12 control), subjects ≥16 y, and all subjects. For P131 there were 12 controls and 20 T1Ds (ages: 19.2 ± 0.83 and 18.8 ± 2.07 y). Retinal photos showed no classical retinopathy.

Results : For M18 and W20 the worst 3 to 9 regions out of 18 or 20 performed best, indicating focal changes. The combined sensitivity and delay scores performed best. For all subjects the AUROCs for M18 and W20 were 87.5 ± 4.78 and 86.2 ± 5.25% (mean ± SE) for the worst 3 TDs/field. PDs of the younger group gave: 89.7 ± 4.70 and 88.7 ± 5.20%. For sensitivities alone AUROCs were in the mid-70% range (Figure) but combining sensitivity TDs from the spatially independent M18 and W20 tests gave 86.8 ± 5.06%. AUROC for the worst 9 PDs of the P131 combined scores was 77.9 ± 8.50%.

Conclusions : Given that the young people with T1D had no classical retinopathy the diagnostic power of the functional tests was good. The rapid M18 and W20 seemed to outperform P131. The focal damage indicated the effects were not iris neuropathy, which would mimic global OFA changes. The M18 stimuli match the size and shape of the ETDRS retinal thickness grid found on OCT reports allowing easy comparison of structure and function as has been shown in macular degeneration [doi:10.1016/j.xops.2022.100143]. The short 82-second tests are ideal for young people.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.

 

Bars 1 to 4: M18 and W20 %AUROCs for combined per-region sensitivities and delays; ‘All’ means all T1D, ‘<16’ younger T1D. Bar 5: M18 sensitivities alone. Bar 6: combined M18 and W20 sensitivities.