Biomicroscopy versus fluorescein angiography of the iris in the detection of diabetic iridopathy

Abstract

Iris fluorescein angiography is not commonly employed in clinical practice, but it is the most sensitive technique for the evaluation of iris vessel abnormalities. We used iris fluorescein angiography as the gold standard against which to test the ability of iris biomicroscopy to demonstrate diabetic iridopathy (DI). One hundred and fourteen eyes of 63 diabetic patients affected by preproliferative or proliferative diabetic retinopathy (DR) (the DR groups at high risk of developing DI) were considered. The DI fluorangiographic classification used was: (1) absence of DI; (2) nonproliferative DI; (3) proliferative DI. The sensitivity of biomicroscopy in detecting DI turned out to be 57%, while the specificity was 94%. The positive predictive value was 93% and the negative predictive value 50%. Our study proved that biomicroscopy can accurately judge when DI is absent. When it is present, however, there is a high probability that biomicroscopy will be less precise in the detection of iris lesions.

Diabetic retinopathy

“…In case of doubt, examination of the anterior chamber angle and FAG of the iris vessels can help, as sensitivity and specificity of the latter are higher than those of biomicroscopy [50]. Iris angiography is also helpful when cataract or vitreous haemorrhage prevent retinal examination because, if iris new vessels are detected, PDR is highly likely to co-exist.…”

Neovascular glaucoma treated by intravitreal triamcinolone acetonide

“…Mean intraocular pressure (IOP) was 31.8 ± 12.7 mmHg. The extent of iris neovascularization was graded using a scale ranging from 0−4, where 0 = no rubeotic iris vessels and 4 = maximal iris neovascularization (Bandello et al 1993). The mean grade of iris neovascularization was 2.5 ± 1.0.…”

Iris indocyanine green videoangiography in diabetic iridopathy.

“…Some studies showed the occurrence of the capillary closure process in the macular region in NPDR too, with consequent foveal avascular zone enlargement.1 [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Although the number of cases affected by NPDR was restricted, we searched retrospectively for a correlation between evidence of quantitative or qualitative abnormalities of foveal avascular zone and iris hypoperfusion, without achieving a positive result. Therefore, capillary dilatations and iris hypoperfusion seem to be a manifestation of diabetic microangiopathy that are relatively independent from the severity of DR.…”