RESUMO
PURPOSE: Cataracts and diabetes very commonly coexist. The aim of the present study was to quantify the effect of uncomplicated phacoemulsification on retinal microvasculature in diabetic patients by using optical coherence tomography angiography (OCTA). METHODS: A prospective observational study of diabetic and nondiabetic patients at baseline and 1 day, 1 week, 1 month, and 3 months after cataract surgery was performed by using OCTA. We measured the macular thickness (MT), superficial capillary plexus (SCP), deep capillary plexuses (DCP), and foveal avascular zone (FAZ) in the 3 × 3 mm macular images. RESULTS: A total of 32 eyes of 32 type 2 diabetic patients and 40 eyes of 40 nondiabetic patients were assessed. There was a significant increase in MT at 1 month and 3 months after surgery in both groups (all P < 0.05), but there was no significant difference between the two groups (P=0.217). At 3 months postoperatively, the SCP level in the diabetic group was significantly higher than that at baseline (P < 0.05). The MT and SCP were negatively correlated with logMAR best-corrected visual acuity (BCVA), while the FAZ area and perimeter were positively correlated with logMAR BCVA in the diabetic group. CONCLUSIONS: Our study demonstrated that phacoemulsification can increase macular thickness in both diabetic and nondiabetic patients and increase SCP in diabetic patients within 3 months after surgery. Whether these changes persist for a longer period still needs to be investigated.
RESUMO
PURPOSE: To explore regional variation of the macular microvasculature in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD), also to detect the association between retinal macular microvascular parameters and the progress of preclinical AD. METHODS: Prospective study of healthy controls, patients with MCI and patients with AD by using Optical coherence tomography angiography (OCT-A). We quantified foveal avascular zone (FAZ) areas, densities of the superficial retinal capillary plexuses (SRCP) and deep retinal capillary plexuses (DRCP). The SRCP and DRCP were divided into inner (3 mm) and external (6 mm) annular rings, each containing four quadrants (SI, II, TI, NI, SE, IE, TE and NE). The data were analysed statistically by using SPSS 22 software. RESULTS: Totally, 60 subjects including 21 HC (33 eyes), 21 patients with MCI (32 eyes) and 18 AD patients (28 eyes) were recruited. The microvascular densities of DRCP at all quadrants of the parafovea and perifovea were significantly lower in AD patients compared to HC group (p < 0.05). Compared to the HCs, MCI patients showed significant microvascular loss in most sectors of the parafovea and the SE sector of the DRCP (p < 0.05), but not in the parafovea (p = 0.829) or perifovea (p = 0.824) of the SRCP. No significant difference was found in microvascular density of SRCP among the groups, except at SI between the AD and HC groups (p = 0.048). CONCLUSION: Our findings demonstrated the macular microvascular attenuation in MCI and AD patients. Both AD and MCI patients showed retinal microvascular density loss, which is more significant in the deep retinal capillary plexuses. Optical coherence tomography angiography (OCT-A) can be used to identify early microvascular abnormalities in AD and MCI. Quantified microvascular density in the DRCP might serve as potential biomarkers of early sign of AD then contribute to forestall the progression of preclinical AD.
