Nail Folds Capillaries Abnormalities Associated With Type 2 Diabetes Mellitus Progression and Correlation With Diabetic Retinopathy

Abstract

Background: Diabetic retinopathy (DR) is an important microvascular consequence of long-term type 2 diabetes mellitus (T2DM), and it can lead to blindness if not properly diagnosed and managed. Nailfold video capillaroscopy (NVC) is a non-invasive technique for observing capillary microvasculature. Aim: We aimed to evaluate the nail folds capillaroscopic alterations in patients with T2DM by NVC and correlated the results to DR, and their relation to disease duration and hemoglobin A1c (HbA1c). Methods: This cross-sectional study enrolled 62 cases with T2DM (as per the American Diabetes Association criteria). All patients were subjected to NVC and ophthalmological assessment. Results: NVC revealed that Patients with DR showed significantly higher frequencies of tortuous capillaries, branched capillaries and precapillary edema versus non-DR patients with P < .05. The DR patients with longer disease duration (15-20) years had significantly higher frequencies of branched capillaries, tortuous capillaries, microhemorrhages, and dilated apical capillaries. The frequency of tortuosity and precapillary edema were significantly higher in patients with poor glycemic control. The increased capillary width and branched capillaries were detected as predictors of DR in multivariate analysis. Conclusion: NVC is a cost-effective, quick, safe, simple, non-invasive, and newly emerging tool to assess the capillaroscopic alterations in diabetic patients as an indicator of severity of DR.

Relationship between nailfold capillaroscopy parameters and the severity of diabetic retinopathy

“…Thus, the current study, based on quantitative nailfold capillaroscopy, showed that NC parameters in diabetic patients were closely associated with the presence of DR and PDR in multivariate analyses. A previous study used another (video-based) method for nailfold capillaroscopy to quantitatively evaluate the NCs, finding that vasodilation of the NCs was a good indicator of DR; it could identify DR with an AUC of 0.75 [ 9 ]. However, this result contradicts ours.…”

“…The current study had several limitations. First, because of the cross-sectional study design, it was not possible to discuss the time course of the association between NC alterations and DR. Second, previous reports have discussed the relationship between DR and other NC structural changes, such as avascular zones and hemorrhages [ 8 , 9 ], but we did not examine these in the current study; we focused only on quantitative NC parameters. Third, we could not obtain information on the duration of diabetes or a history of smoking, which may be possible factors involved in the progression of DR. Fourth, total cholesterol and LDL were, paradoxically, lower in diabetic patients than in the normal controls, which may be explained by the fact that 41 patients (41/83: 49.4%) were taking oral antihyperlipidemic medication.…”

“…More recently, the relationship of NC parameters with DM and DR has been explored. Some studies suggest an association between a higher number of NC crossings and DR, while others point to increased NC width and branching, as well as alterations such as increased tortuosity, bushy NCs, aneurysm, neoformation, and bizarre NCs as possible indicators of DR [ 7 – 9 ]. Nonetheless, previous reports have not used automatic assessment of NC parameters, making it difficult to eliminate the effects of grader subjectivity.…”

Full-field amplitude speckle decorrelation angiography

“…Hence, there is a strong interest in imaging microvascular activity in different biological tissues such as the brain [7], retina [8], oral mucosa [9], and skin [10]. Skin microvascular imaging is of particular interest since the skin is easily accessible, and monitoring changes in its microvascular activity can be used both as a tool to directly assess different skin conditions (such as psoriasis [11], burn wounds [12], systemic sclerosis [13], and skin cancer [14]), and as a means to indirectly monitor diseases that affect other organs and induce changes in skin microvasculature [2] (such as chronic kidney disease [15], diabetes [16] and peripheral vascular diseases [17]).…”