Analysis Of The Characteristics Of Nerve-retinal Structure And Function In Diabetic Retinopathy With Large Range Non-perfusion Area

Purposes:Diabetic retinopathy(DR),as the most serious complication of diabetes mellitus(DM)in the eye,has become the leading blind eye disease in the working age group.Diabetic retinopathy includes retinal microangiopathy and retinal neuropathy.There are many studies on the former clinically,including the diagnosis and treatment of retinal microvascular injury and its complications.However,the latter is not enough,and strengthening the research on diabetic retinal nerve injury and retinal neuroprotection will help to correctly understand the disease.The essence is of great significance for preventing and reversing diabetic retinal neuropathy.This study is to investigate the changes of retinal nerve structure and function after pars planavitrectomy of patients with diabetic retinopathy with large range non-perfusion area(DR with LNPA)and proliferative diabetic retinopathy(PDR),in order to explore the damage of neurological structure and function of diabetic retinopathy,and to prevent and diagnose DR with LNPA retinal nerve injury,and provides a strong reference for treatment.Method : This study was a retrospective case-control study.The study population consisted of 109 patients(176 eyes)who underwent pars planavitrectomy for PDR from the Ophthalmic Center of Qingdao Municipal Hospital from May 2014 to July 2018.The patients were divided into DR without LNPA group and DR with LNPA group according to the range of non-perfusion area in the posterior pole of FFA.In DR without LNPA group,there were 81 patients(133 eyes),including 47 males and 34 females,with an average age of(56.49±3.63)years,diabetes duration of 1-30 years,average diabetes duration of(11.12±5.50)years,average glycosylated hemoglobin(HbA1c)of(8.56±1.72)%,average eye axis length of(23.55±0.29)mm,and average retinal laser points of(1304.59±209.13)during operation.In the group of DR with LNPA,there were 28 patients(43 eyes),including 16 males and 12 females,with an average age of(56.60±3.06)years,diabetes duration of 1-30 years,average diabetes duration of(15.81±6.07)years,average glycosylated hemoglobin(HbA1c)of(15.81±6.07)%,average eye axis length of(9.24±1.46)mm,and average retinal laser points of(1525.00±297.60)during operation.All patients underwent full field ERG,OCT and fundus fluorescence angiography(FFA).All the data was analyzed by SPSS24.0 statistical.Descriptive statistical analysis was conducted for general data of two groups.Two independent samples t-test(continuous variable)or?2 test(classification variable)were used for comparison between different groups.Covariance analysis was used to compare the observation indexes among different groups,and age,sex,course of disease and glycosylated hemoglobin were adjusted.The difference was statistically significant with P < 0.05.Result:General situation: the duratiom of DM(P < 0.001),preoperative HbA1 c level(P = 0.013)and intraoperative laser counts(P < 0.001)were significantly different between the two groups,but there was no significant difference in gender,age,and eye axis length between the two groups(P > 0.05).ERG Test:In DR without LNPA group and DR with LNPA group,the amplitudes of a-wave,b-wave and OPs decreased in Photopic 3.0 ERG and Scotopic 3.0 ERG.In DR with LNPA group,the amplitudes of a-wave and b-wave in Photopic 3.0 ERG decreased significantly compared with DR without LNPA group(P=0.01,P<0.001).The amplitude of a-wave and b-wave in Scotopic 3.0 ERG in DR with LNPA group was significantly lower than that in DR without LNPA group(P<0.001,P<0.001).There was significant difference between DR with LNPA group and PDR group.The decrease of OPs amplitude in DR with LNPA group was significantly different from that in DR without LNPA group(P<0.001).The latency of a-wave and b-wave in Photopic 3.0 ERG and Scotopic 3.0 ERG in DR without LNPA group and DR with LNPA group were delayed.There was a significant difference in the latency delay between DR with LNPA group and DR without LNPA group(P<0.001;P=0.018)in Photopic 3.0 ERG.The latency delays of a-wave and b-wave in Scotopic 3.0 ERG in DR with LNPA group were significantly different from those in DR without LNPA group(P=0.004,P<0.001).The delayed latency of Ops in DR with LNPA group was significantly different from that in DR without LNPA group(P=0.021).The analysis of GCIPL:In the DR without LNPA group and the DR with LNPA group,the GCIPL thickness in each quadrant of the macular area and the average GCIPL thickness in the macular area decreased,especially in the lower and subnasal quadrants.Compared with the DR without LNPA group,the GCIPL thickness in the DR with LNPA group decreased more significantly than that in the DR without LNPA group.Compared with DR without LNPA group,the GCIPL thickness in the upper quadrants(P=0.01),lower quadrants(P<0.001),inferior nasal quadrant(P=0.001),subnasal quadrants(P<0.001),infratemporal quadrant(P=0.011)and average GCIPL thickness(P<0.001)have significant difference.The thickness of GCIPL in the upper temporal quadrant was not significantly different from that in the two group(P=0.918).Conclusion:DR with LNPA is a special type of PDR,and its neuroretinal structure and function damage are more serious than that of PDR patients.