Observation on Macular Blood Flow Density of Patients with No Obvious Sight Loss Caused by Diabetes and Study on Traditional Chinese Medicine Syndrome Types
Abstract:Objective:To discuss the macular blood flow density of patients with no obvious sight loss caused by diabetes,the area changes of central foveal avascular zone (FAZ) and the change law of macular blood flow density of different traditional Chinese medicine (TCM) syndrome types. Methods: A total of 98 patients (192 eyes) with type II diabetes were collected and set as the diabetes group, which was further divided into two subgroups according to the results of fundus examination with VOLK lens + pre-set lens of 90D slit lamp, including the non- proliferative diabetic retinopathy (NPDR) group with 46 cases (91 eyes) with non-proliferative retinal microangiopathy,and the diabetes at stage 0 group with 52 cases (101 eyes) with no retinopathy;another 44 healthy persons were selected (84 eyes) as the control group. All enrolled subjects were given optical coherence tomography angiography (OCTA) examination to get the macular blood flow density of superficial retina and macular FAZ area. The macular blood flow density and FAZ area in each group were compared; the correlation of different gender, course of diabetes, glycosylated hemoglobin, fasting blood sugar, 2- hour postprandial blood glucose and TCM syndrome types with macular blood flow density and FAZ area of patients with diabetes was analyzed. Results:There was no significant difference being found in the comparisons of macular blood flow density and FAZ area between male and female patients with diabetes (P>0.05). Comparing the macular blood flow density of patients with diabetes of different courses, there was significant difference (P<0.05); in pairwise comparison, the blood flow density of patients with a course of ≥10 years was lower than that of those with a course<5 years (P<0.05); there was no significant difference being found in the comparison of blood flow density between patients with a course of 5-10 years and those with a course of<5 years and ≥ 10,respectively (P>0.05);there was no significant difference being found in the comparisons of average FAZ area between patients with different courses (P>0.05). There was significant difference being found in the comparisons of macular blood flow density and FAZ area between patients with diabetes of different levels of glycosylated hemoglobin (P<0.05);the pairwise comparison showed that the macular blood flow density of patients with levels of glycosylated hemoglobin of>9% was lower than that of patients with levels of glycosylated hemoglobin of<7% and 7%- 9% , respectively (P<0.05), and the FAZ area was bigger than that of patients with levels of glycosylated hemoglobin of<7% and 7%-9%,respectively (P< 0.05);the macular blood flow density of patients with levels of glycosylated hemoglobin of 7%- 9% was lower than that of patients with levels of glycosylated hemoglobin of<7% (P<0.05),and the FAZ area was bigger than that of patients with levels of glycosylated hemoglobin of<7%. There was significant difference in the comparisons of macular blood flow density and FAZ area between patients with diabetes of different TCM syndrome types (P<0.05);the pairwise comparison showed that the macular blood flow density of patients with syndrome of dual deficiency of qi and yin and syndrome of dual deficiency of yin and yang was lower than that of patients with syndrome of internal accumulation of phlegm- damp and syndrome of yin deficiency with internal heat (P<0.05);the FAZ area of patients with syndrome of dual deficiency of qi and yin and syndrome of dual deficiency of yin and yang was larger than that of patients with syndrome of internal accumulation of phlegm-damp and syndrome of yin deficiency with internal heat (P<0.05),and the FAZ area of patients with syndrome of dual deficiency of qi and yin was larger than that of patients with syndrome of dual deficiency of yin and yang (P<0.05). There was no correlation between the levels of fasting blood sugar and macular blood flow density and FAZ area of diabetic patients (P>0.05);there was a negative correlation between levels of 2hPBG and macular blood flow density (P<0.05) and a positive correlation with FAZ area (P<0.05). There was significant difference in the comparisons of macular blood flow density and FAZ area between the NPDR group, the diabetic at stage 0 group, and the control group (P<0.05); in the pairutse comparison, the macular blood flow density in the NPDR group and diabetes at stage 0 group was lower than that in the control group (P<0.05),and the macular blood flow density in the NPDR group was lower than that in the diabetes at stage 0 group (P<0.05);the FAZ area in the NPDR group was greater than that in the diabetes at stage 0 group and the control group (P<0.05),and there was no significant difference being found in the comparison of FAZ area between the diabetes at stage 0 group and the control group (P>0.05). Conclusion:Patients with no significant visual loss caused by diabetes had meaningful changes in macular blood flow density and FAZ area when their central vision was not affected, regardless of whether they had changes in retinopathy in the fundus, which worsens with disease progression; there was variability in macular blood flow density and detected FAZ area in patients without significant visual loss caused by diabetes of different TCM syndrome types.