Abstract
Purpose :
To analyze the evolution of macular vessel density (VD) within three vascular plexuses using optical coherence tomography angiography (OCTA) over 1 year in patients with uncontrolled type 1 diabetes (T1D).
Methods :
Retrospective study of 12 eyes of 8 T1D patients with early worsening diabetic retinopathy imaged with OCT-Angiography (RTVue XR Avanti; Optovue, Fremont, CA, USA) with phase 7 AngioVue software implemented with the Projection Artifacts Removal (3D-PAR). 3x3 mm scans centered on the fovea were analysed and follow-up examination mode was employed.
Inclusion criteria were: T1D, age <40 years, presence of bilateral and rapidly progressive (over a 6-month period) DR requiring prompt and dense panretinal photocoagulation (PRP), abscence of past or present diabetic ME (DME), good OCT-A image quality.
Data were collected at the time of panretinal photocoagulation initiation and after 6 and 12 months, including VD within 3 retinal plexuses - superficial (SVP), intermediate (ICP) and deep (DCP); foveal avascular zone (FAZ) area, acircularity index (AI) and flow density (FD)-300; central macular thickness (CMT); HbA1c levels.
Results :
Patient mean age was 28.9 ± 5.4 years, 5 were males. A history of rapid reduction in blood glucose was found in 7 out of 8 cases. VD was significantly decreased in all vascular plexuses at 6 and 12 months: in the SVP it falled from 43.55±4.31 to 39.87±7.34 (p=0.008), in the ICP from 41.95±4.13 to 36.82±7.89 (p=0.03), and in the DCP from 21.94±4.08 to 19.06±4.62 (p=0.004). ICP and DCP VD changes were significantly correlated (r=0.81, p<0.001). The mean FAZ area increased from 0.41 ± 0.23 mm2 to 0.45 ± 0.28 mm2 (p=0.07) and 0.49 ± 0.30 mm2 (p=0.05) at 6 and 12 months (p=0.04) and the FD-300 decreased (p=0.03) over time. No significant change in AI, CMT and visual acuity were observed over time.
Conclusions :
Young T1D patients with uncontrolled diabetes and fast progression of DR treated with PRP showed a rapid decrease in macular VD and an increase in FAZ area at 6 months and continuing over 1 year. The capillary loss was faster in the deep capillary plexuses (ICP and DCP) than in the SVP. Despite these findings, VA didn't significantly decrease over time.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.