Macular Optical Coherence Tomography Angiography in Nephropathic Patients with Diabetic Retinopathy in Iran: A Prospective Case–Control Study

Abstract

Background: Diabetic macular ischemia (DMI) is an important category of diabetic retinopathy (DR) which leads to severe visual loss. Clinically, it is defined by an enlargement of the foveal avascular zone (FAZ) that can be detected by optical coherence tomography angiography (OCTA). Studies have described a relationship between renal disease and these changes in FAZ area. The aim of this study was to compare disturbances in FAZ area in diabetic patients with or without overt nephropathy. Methods: Following approval of the ethics committee, we examined diabetic patients with retinopathy. Patients were divided into two groups of DR, namely, with overt nephropathy and without overt nephropathy. The FAZ area was measured using OCTA. A P value of \ 0.05 was considered to be statistically significant. Result: A total of 46 patients (78 eyes) were enrolled in this study. All eyes with DR showed significant changes in FAZ area, but the sizes of the FAZ area were larger in both the superficial and deep layers in patients with clinical albuminuria than in those with no microalbuminuria (P = 0.007 and P = 0.002, respectively). Conclusion: These results demonstrate that OCTA provides highly detailed information on retinal microvasculature and that it is a reliable modality to assess DR progression in patients with nephropathy. They also show that renal impairment as a systemic risk factor was associated with enlarged FAZ area in DM.

Optical coherence tomography angiography biomarkers in diabetic nephropathy patients in Thailand : a diabetic eye and kidney diseases (dek-d) study

“…The authors suggested the DN was a significant risk of diabetic macular ischemia. (34) The result of this study concurs with a prior study of Shukla et al which reported significantly enlarged FAZ area from fluorescein angiography in patients with diabetic nephropathy. (35) Choroidal thickness can be detected by a conventional optical coherence tomography angiography (OCT) with special technique called enhanced depth imaging (EDI-OCT) or using SS-OCT which is the principle of OCTA machines.…”

“…Similar to Cankurtaran et al (7) , we could not find any associations between mean FAZ area and DN. However, a prospective case-control study by Ahmadzadeh Amir et al (34) described significantly larger FAZ area of SCP, DCP, and whole retina in participants with overt nephropathy compared with those without. Enlargement of FAZ is contributed by many factors apart from capillary endothelial dysfunction, such as capillary dropout and increased vascular endothelial growth factor.…”

Optical Coherence Tomography Angiography in Type 1 Diabetes Mellitus—Report 2: Diabetic Kidney Disease

“…The status of the FAZ and its different parameters, such as area, perimeter or circularity, has been previously described as a marker associated with DR stage [ 9 , 15 , 18 ], a surrogate marker of VA [ 40 ] or associated to HbA1c levels [ 24 ]. With regard to kidney function, some previous reports have described an association between FAZa and GFR [ 13 ] or ACR [ 27 ], although other authors have not found any association between these parameters [ 29 ]. In our series, we have not observed a significant association with FAZa or FAZp; nevertheless, FAZc has been proven effective to identify patients with greater DKD stages in the three scales evaluated, GFR, ACR and KDIGO prognosis classification.…”

“…Since this technique allows direct noninvasive in vivo visualization of the microvascular circulation, it is sensible to think that the detection of microvascular changes may be associated to other clinical manifestations elsewhere in the body. With this concept, the relationship between OCTA and kidney disease has been investigated in recent reports that have described existing relationships between OCTA parameters and non-specific CKD [ 25 , 26 ] and DKD [ 13 , 27 , 28 , 29 , 30 ]. However, the vast majority of these studies have not been specifically directed to investigate the diagnostic potential of OCTA parameters compared to standard kidney function tests.…”

Optical coherence tomography angiography for assessment of changes of the retina and choroid in different stages of diabetic retinopathy and their relationship with diabetic nephropathy

“…Several studies have evaluated the correlation between DR and DN. The VD of the retina is gradually decreased according to the progression of DN [47,48], and the size of the FAZ area in the SCP and DCP is larger in patients with clinical albuminuria [49]. The level of urinary albumin moderately correlates with the VD of the SCP in patients with diabetes, and eGFR is significantly correlated with the size of retinal nonperfusion (RNP) area in patients with DN [50].…”