Influencing factors and predictive model of macular retinal blood flow density after vitrectomy with PDR / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To explore the changes and influencing factors of macular retinal blood flow density in patients with proliferative diabetic retinopathy(PDR)after vitrectomy, and establish a predictive model.METHODS: The clinical data of 173 patients with 173 eyes in PDR who underwent vitrectomy in our hospital from June 2019 to June 2021 were analyzed retrospectively. According to the changes of macular retinal blood flow density after operation, the patients were divided into normal group(118 cases with 118 eyes)and descending group(55 cases with 55 eyes). The general data, preoperative laboratory examination index and intraoperative condition of the two groups were compared. Multivariate Logistic regression was used to analyze the factors affecting the changes of retinal blood flow density in macular area after operation. Construct the line chart prediction model and evaluate its prediction efficiency.RESULTS: The course of diabetes, proportion of patients with complicated maculopathy, serum TC, TG, LDL-C, HbA1c, vascular occlusion and hyperplastic retinal traction in the decreasing group were significantly higher than those in the normal group, while HDL-C was significantly lower than that in the normal group(P<0.05). Multivariate Logistic regression analysis showed that course of diabetes > 17a(OR=4.526), complicated maculopathy(OR=4.983), HbA1c > 6.25%(OR=4.283), vascular occlusion(OR=5.216)and hyperplastic retinal traction(OR=4.765)were all risk factors of the decrease of macular retinal blood flow density after operation(P<0.05). The line chart prediction model has good differentiation and accuracy, and has high prediction value. CONCLUSION: Course of diabetes, complicated maculopathy, HbA1c, vascular occlusion and proliferative retinal traction are all related to the decrease of macular retinal blood flow density after vitrectomy with PDR. Understanding the risk factors is beneficial to surgical decision-making.

Correlation of Risk Factors with Severity of Diabetic Retinopathy - A Retrospective Study.

Diabetic retinopathy (DR) is a major microvascular complication of diabetes. It is the most common cause of blindness in the working-age population in developed countries. We wanted to analyse the correlation between risk factors of blindness like duration of diabetes, dyslipidaemia, hypertension, HbA1c with severity of diabetic retinopathy in order to design appropriate strategies for prevention and treatment of diabetic retinopathy.METHODSThis was a retrospective study of all diabetic patients with diabetic retinopathy who presented to the eye OPD at KS Hegde Medical Academy from April 1st 2018 to March 31st 2019 that fulfilled the inclusion criteria. A dilated fundus examination was done to note the grade of diabetic retinopathy. The demographic data along with the duration of diabetes, HbA1c values, Cholesterol levels and Blood pressure were documented and correlated with the severity of diabetic retinopathy.RESULTSThe study included 92 patients, of which 63 were males and 29 were females with a mean age of 54.5±2.8 years. We found that there was statistically significant association between the duration of diabetes and HbA1c levels with severity of diabetic retinopathy (p= 0.022 and 0.034 association), whereas there was no statistically significant correlation between blood pressure and cholesterol levels with severity of diabetic retinopathy (p= 0.52 and 0.456 respectively)CONCLUSIONSDiabetic retinopathy showed a male preponderance, with risk factors like duration of diabetes and HbA1c levels having a significant association with the severity of diabetic retinopathy. Therefore, it is essential to have a good systemic control of diabetes with diet and suitable medications. Diabetic retinopathy is a preventable cause of blindness when diagnosed early and screening of diabetic retinopathy must be done in all diabetics to prevent the progression of the disease.

Long-term Effect of Panretinal Photocoagulation Combined With Intravitreal Bevacizumab in High-risk Proliferative Diabetic Retinopathy

PURPOSE: To evaluate long-term effects and usefulness of combined intravitreal injection of bevacizumab and panretinal photocoagulation (PRP) in patients with high-risk proliferative diabetic retinopathy. METHODS: The authors retrospectively reviewed the records of 40 patients (40 eyes) with high-risk proliferative diabetic retinopathy who had been treated with PRP alone (laser treatment group, n=20) or intravitreal bevacizumab before PRP (combined treatment group, n=20). Changes in best corrected visual acuity (BCVA), central macular thickness (CMT) and the total area of leakage from active new vessels (NVs) were compared between the groups at one, three, and six months and at one year post-treatment. RESULTS: In the combined treatment group, CMT decreased significantly at one month (p=0.021), and the areas of active NVs decreased significantly at one month (p=0.001) and three months (p=0.014) compared to those of the laser treatment group. However, there were no differences between the two groups after three months. In the combined treatment group, elevated intraocular pressures were found in three cases after one month, and there were vitreous hemorrhages in two cases after three months. CONCLUSIONS: The combined treatment showed significant early improvements in BCVA, CMT, and NVs regression for up to three months. However, long-term follow-up and additional treatment was necessary in the patients with persistent or recurred NVs and macular edema after three months.

The Clinical Significance of Venous Filling Time through Panretinal Photocoagulation in Proliferative Diabetic Retinopathy

PURPOSE: To verify the clinical correlation between retinopathy progression and the change of venous filling time (VFT), measured before and after panretinal photocoagulation (PRP), in proliferative diabetic retinopathy (PDR) patients. METHODS: We conducted this study on 32 patients (32 eyes) who received PRP for PDR. These patients were subdivided into two groups in accordance with the clinical course of PRP: the stabilized group in which retinal neovascularization was regressed and the progressed group in which retinal neovascularization was continued and a complication, such as vitreous hemorrhage or tractional retinal detachment, was developed within 12 months of laser treatment. Arteriovenous passage time (AVP) and VFT were measured by video fluorescein angiogram (FAG) using scanning laser ophthalmoscope (SLO) before and after PRP. VFT values were assigned by measuring by the time duration from start of venous lamina flow to the fullness of fluorescence on the vascular arch. RESULTS: In the stabilized group, AVP was decreased by 0.20+/-0.89sec and VFT was decreased by 0.30+/-1.69 sec through PRP. In the progressed group, AVP was increased in 0.12+/-1.22 sec and VFT was increased by 0.99+/-1.60 sec through PRP. In both groups, the VFT changes were significant (P=0.04) but the AVP changes were not (P=0.34). CONCLUSIONS: VFT was significantly decreased in the stabilized group and significantly increased in the progressed group after PRP. Accordingly, we suggest that VFT changes after PRP can be utilized as a prognostic indicator for evaluating clinical course of diabetic retinopathy after performing PRP and for monitoring the clinical effect of PRP.

Efficacy of Intravitreal Triamcinolone Acetonide Injections at the End of Pars Plana Vitrectomy in Proliferative Diabetic Retinopathy

PURPOSE: To evaluate the efficacy of intravitreal injections of triamcinolone acetonide (TA) at the end of pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR). METHODS: We analyzed 50 patients (52 eyes) who underwent PPV for treatment of PDR and received an intravitreal injection of 4 mg TA at the end of surgery. The study group (Group 1) was compared with a control group (Group 2, 46 patients, 51 eyes) (matched with the study group for preoperative parameters) who underwent PPV without intravitreal injection of TA. RESULTS: In Group 1, the grade of anterior chamber cells at postoperative days 1 and 7 was significantly lower than that of Group 2. There was slight mean IOP elevation in Group 1 at postoperative weeks 2, 3, 4, and 8, but it was not statistically significant. Forty-four eyes (84.6%) from Group 1 showed better visual acuity at the last follow-up than at the preoperative visit (Group 1). Thirty-two eyes (62.8%) from Group 2 showed better visual acuity at the last follow-up than at the preoperative visit. The degree of visual improvement was 0.75 logMAR in Group 1 and 0.59 logMAR in Group 2. Vitreous hemorrhage occurred in 9 eyes (17.3%) from Group 1 and in 19 eyes (37.3%) from Group 2. However, the differences in the occurrence of neovascularization in iris and neovascular glaucoma between two groups were not statistically significant. CONCLUSIONS: Intravitreal TA injection at the end of PPV seems to be effective in improving visual acuity and decreasing early postoperative inflammation and the frequency of vitreous hemorrhage.