Clinical Observation Of Dexamethasone Implant In The Treatment Of Diabetic Macular Edema With Different OCT Types

Objective:The purpose of this study was to compare the short-term efficacy and safety of intravitreal dexamethasone implantation in patients with diabetic macular edema according to different OCT types.Methods:This study was a prospective study.35 patients（35 eyes）with DME were diagnosed by scanning laser ophthalmoscope（Optomap）,OCT and fluorescein angiography（FFA）.The patients were divided into groups according to the macular retinal tomographic images collected by OCT scanner.Patients with spongiform edema larger than 2 op tic disc diameter（DD）were divided into diffuse retinal thickening（DRT）group（12 eyes）.Patients with cystic edema with different sizes of low reflex were included in the cystoid macular edema（CME）group（14 eyes）.Patients with subretinal effusion eminence and detachment in the central macular area were divided into serous retinal detachment（SRD）group（9 eyes）.After diagnosis,all patients underwent medical history collection and ophthalmic examination,and the data of preoperative best-corrected visual acuity（BCVA）,central macular thickness（CMT）and intraocular pressure（IOP）were collected.After completing the surgical risk assessment,dexamethasone vitreous implants were performed,and postoperative follow-up was performed for a period of 6 months.All the patients received ophthalmology physical examination to evaluate the postoperative complications during the follow-up of 1,2,3 and 6months,and the data of BCVA,CMT and IOP were collected by the same way and instrument,and the differences among the three groups of patients at eac h follow-up point were analyzed.Results:1.During the postoperative follow-up period,the BCVA of the three groups were improved,and the patients of the DRT group were better as a whole,and there were differences in time and between groups(P_time<0.001,P_group=0.006).The best BCVA of the three groups appeared at the second month after operation,and then decreased.2.After operation,CMT decreased in all three groups,and there was significant difference in CMT at each follow-up point（P<0.001）,but there was no significant difference between groups（P>0.05）.During the follow-up,the lowest value of CMT was the second month after operation,and then began to rebound.3.The IOP of all patients increased in varying degrees after operation,and the peak value appeared at the second month after operation,and then began to decrease（P<0.001）.There was no significant difference between the two groups（P>0.001）.4.During the follow-up period,no significant aggravation of cataract or other serious adverse events related to treatment were found.All patients with elevated IOP were controlled by local medication and did not need to receive laser or surgical treatment.Conclusion:Dexamethasone intravitreous implant can safely and effectively improve the visual function and macular retinal morphology of DME patients with different OCT types,and there is a difference in short-term efficacy among diabetic macular edema patients with different OCT types,and the overall benefit of DRT group is better than that of the other two groups.It is suggested that early treatment is particularly important for the final recovery of visual function in patients with DME.