Application of iris fluorescein angiography in diabetic iridopathy and retinopathy in brown iris

Purpose: This study aimed to evaluate the relationship between diabetic iridopathy (DI) and diabetic retinopathy (DR) and distinguish iris neovascular and physiological leakage using iris fluorescein angiography (IFA). Methods: A total of 210 subjects were prospectively recruited in this study. Sixty normal subjects were divided equally into three groups (<40 years old, 40-59 years old, and 60-79 years old). One hundred fifty patients with diabetic mellitus (DM) were divided equally into five groups (no retinopathy, mild non proliferative DR (mildnPDR), moderate nPDR, severe nPDR, and PDR group). Normal subjects underwent IFA. Patients with DR underwent both IFA and ultrawide field fundus fluorescein angiography (uwFFA) at the same time. The leakage time and area were recorded and compared with each group. Results: Fluorescein leakage occurred at the pupillary edge of patients that were 40-59 and 60-79 years old but not in those <40 years old. In the PDR group, the leakage time was earlier and the leakage area was larger than nPDR and patients with no retinopathy (p = 0.039 and p = 0.005, respectively). However, the leakage time and area were not significantly different between patients with no retinopathy and nPDR (p > 0.05). Conclusion: IFA examination can only assist in estimating the fundus severity of PDR patients, whereas the fundus changes of patients with no retinopathy and nPDR were not related to DI changes. Trial registration No.: ChiCTR1800018003. The date of registration: Aug 26th, 2018.