Abstract
Purpose :
Diabetic retinopathy is characterized by disturbances in retinal blood flow. The retinal blood flow is autoregulated by adaptation of the diameter of resistance vessels to changes in blood pressure and metabolism and by spontaneous oscillations in the diameter of retinal arterioles, socalled vasomotion. Retinal vasomotion has been shown to be disturbed in diabetic patients with mild retinopathy, but it is unknown whether the changes are further disturbed when retinopathy progresses to either diabetic macular edema (DME) or proliferative diabetic retinopathy (PDR).
Methods :
Fundus video recordings (25 frames/sec) were used to study spontaneous oscillations in the diameter of large temporal retinal arterioles during rest in eleven patients with mild diabetic retinopathy; twenty patients with diabetic macular edema and ten patients with proliferative diabetic retinopathy. Fourier analysis was performed to calculate the amplitude of the diameter changes for the very low (VLF: 0.1-1.4 Hz), low (LF: 1.4-2.8 Hz), high (HF: 2.8-4.2 Hz), very high (VHF: 4.2-5.6 Hz) and ultra-high (HF: 5.6-23.7 Hz) frequency bands.
Results :
The amplitude of the oscillations in patients with mild diabetic retinopathy were (mean±SD): VHL (3.15 ± 4.32), LF (2.75 ± 2.16), HF (1.62 ± 0.85), VHF (4.58 ± 1.23) and UHF (6.91 ± 2.15). In the patients with DME the amplitude was significantly (p=0.01) lower (1.10 ± 0.12) in the LF band, whereas in patients with both DME and PDR the amplitude was signficantly (p=0.004 and p=0.02) higher (9.81 to 1.10 ± 0.12 and 8.66 ± 1.02) in the UHF band.
Conclusions :
Reduced amplitudes of spontaneous diameter oscillations of retinal arterioles among patients with mild diabetic retinopathy are further disturbed when retinopathy progresses to either diabetic macular edema (DME) or proliferative diabetic retinopathy (PDR). Disturbances in vasomotion may play a role in the pathophysiology of diabetic retinopathy.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.