Objective To observe the clinical efficacy of pars plana vitrectomy (PPV) combined with dexamethasone intravitreal implant (DEX) in the treatment of proliferative diabetic retinopathy (PDR). MethodsA prospective randomized controlled study. A total of 57 PDR patients with 79 eyes diagnosed by Department of Ophthalmology of The First Affiliated Hospital of Nanjing Medical University from May 2021 to February 2023 were included in the study. Best corrected visual acuity (BCVA) and optical coherence tomography (OCT) were performed in all affected eyes. Central macular thickness (CMT) was measured by OCT. The patients were randomly divided into control group and experimental group, with 27 cases and 35 eyes and 30 cases and 44 eyes, respectively. All eyes were treated with routine 25G PPV and intraoperative whole-retina laser photocoagulation. At the end of the operation, the experimental group was given 0.7 mg DEX intravitreal injection. At 1, 4, 12, and 24 weeks after operation, the same equipment and methods were used for relevant examinations. The improvement after surgery was assessed according to the diabetic retinopathy severity score (DRSS). Mixed analysis of variance was used to compare logarithm of the minimum angle of resolution BCVA and CMT between the two groups and within the two groups before and after operation. ResultsAt 1, 4, 12 and 24 weeks after surgery, BCVA was significantly improved at different time points after surgery, and the differences were statistically significant (P＜0.001). At different time after operation, BCVA and CMT in experimental groups were significantly better than that in control group, with statistical significance (P＜0.05). Compared with the CMT before surgery, the CMT at all time point after surgery in experimental group were significantly decreased, and the difference were statistically significant (P＜0.05). There was no significant difference one week after eye operation in control group (P=0.315). At 4, 12 and 24 weeks after operation, CMT decreased in control group, and the differences were statistically significant (P＜0.05). Compared with before surgery, DRSS increased two steps higher at 1, 4, 12 and 24 weeks after surgery in 20 (45.45%, 20/44), 26 (59.10%, 26/44), 32 (72.73%, 32/44) and 31 (70.45%, 31/44) eyes in the experimental groups, respectively. The control group consisted of 15 (42.86%, 15/35), 15 (42.86%, 15/35), 16 (45.71%, 16/35) and 18 (51.43%, 18/35) eyes, respectively. There was no significant difference in DRSS at 1, 4 and 24 weeks after operation between the control group and the experimental group (P=0.817, 0.178, 0.105). At 12 weeks after surgery, the difference was statistically significant (P=0.020). ConclusionPPV combined with intravitreal injection of DEX in the treatment of PDR can improve postoperative visual acuity, alleviate postoperative macular edema and improve the severity of DR.
ObjectiveTo observe the long-term effects of anti-vascular endothelial growth factor (VEGF) drug initiation combined with dexamethasone intravitreal implant (DEX) on the structural integrity of the outer macular region of the eye in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO). MethodsA retrospective clinical study. From February 2018 to August 2022, 54 patients diagnosed with CRVO combined with ME (CRVO-ME) in Department of Ophthalmology of Central Theater Command General Hospital were included in the study. Among them, there were 30 males and 24 females, all with monocular disease. According to different treatment regiments, patients were divided into anti-VEGF and DEX combination therapy group (initial combination group), anti-VEGF drug monotherapy group (monotherapy group) with 21 eyes and 33 eyes, respectively. Best corrected visual acuity (BCVA), optical coherence tomography (OCT) examination were performed in all eyes. The thickness of foveal retina (CRT) and the deficiency length of outer membrane (ELM), ellipsoid band (EZ) and chimaera band (IZ) in the 1 mm macular area were measured by OCT. The initiating combination group was treated with anti-VEGF agents or DEX as assessed on demand (PRN) after the combination therapy, and the monotherapy group received 3+PRN regimen. Relevant examinations were performed at 1 (V1), 6 (V6), 12 (V12) months and observation cut-off or the last visit (Vf) after treatment using the same equipment before treatment. The deletion length of ELM, EZ and IZ in V1, V6, V12 and Vf after treatment were compared between the two groups. Repeated measurement ANOVA was used to compare BCVA, CRT and deletion length of ELM, EZ and IZ at different follow-up times. Spearman rank correlation test was used to analyze the correlation between the two groups of continuous variables. ResultsThe follow-up time of patients in the initial combination group and monotherapy group was (18.05±5.66) and (21.90±10.80) months, respectively, with no statistical significance (F=13.430, P=0.229). Compared with baseline, the deletion lengths of ELM, EZ and IZ were significantly improved (F=11.848, 10.880, 29.236), BCVA was increased (F=10.541) and CRT was decreased (F=52.278) in the initial combination group and the monotherapy group at different follow-up times after treatment. The differences were statistically significant (P＜0.001). At V1, EZ and IZ deletion lengths were (344.10±413.03), (593.33±372.96) μm and (354.71±321.75), (604.85±385.77) μm in the initial combination group and monotherapy group, respectively. The improvement of EZ and IZ deletion lengths in the initial combination group was better than that in the single drug group, and the difference was statistically significant (F=5.272, 6.106; P=0.026, 0.017). The CRT of the initial combination group and the monotherapy group were (248.86±59.99) and (314.72±214.91) μm, respectively, and the CRT of the initial combination group was significantly lower than that of the monotherapy group, with statistical significance (F=6.102, P=0.017). At V6, V12 and Vf, the deletion length of ELM, EZ and IZ and BCVA and CRT showed no statistical significance (P＞0.05). Correlation analysis showed that ELM, EZ, IZ were positively correlated with BCVA and CRT in the initial combination group and monotherapy group (P＜0.001). In V6, V12 and Vf, the number of anti-VEGF drug injections in the initial combination group and monotherapy group was (2.67±1.32), (4.43±2.27), (6.05±3.51), (4.58±0.90), (7.33±1.93), (11.33±6.10) times, respectively. The number of injections in the initial combination group was significantly lower than that in the monotherapy group, and the difference was statistically significant (F=5.150, 0.646, 3.433; P＜0.001). ConclusionsThe improvement of BCVA and CRT in the initial combination group is similar to that in the monotherapy group. Compared with the monotherapy group, EZ and IZ deletion are improved more significantly in the initial combination group, and CRT decreased more rapidly and significantly. The initial combination group receives fewer anti-VEGF injections than the monocular group.