Correlation Study Between RAPDx Parameters And Mydriasis In Patients With Cataract And Diabetes Mellitus

Objective:To explore the effects of diabetes and the duration of diabetes on pupillary response parameters and effects of mydriasis,and to analyze the correlation between different pupillary parameters and pupil size after mydriasis.Methods:This study was a cross-sectional study.Patients with binocular senile cataract were recruited from the outpatient department of Shantou International Eye Center in February 2021 to April 2022.According to the diabetes diagnostic criteria of the Chinese Guidelines for the Prevention and Treatment of Type 2 Diabetes(2020 Edition),the patients were divided into a diabetes group and a control group.All patients were examined by RAPDx pupillary analyzer to obtain pupillary response parameters before using mydriatic drugs.Pupillary response parameters including systolic amplitude,amplitude response,peak systolic velocity,peak diastolic velocity,systolic latency and peak systolic latency directly to light reflex.Collecting basic information and eye examination results for all subjects.A slit lamp camera was used to obtain the pupil size pictures of the patients before mydriasis and after using compound tropicamide for 30 minutes.The pictures of pupil size were measured using Image J software.All data were analyzed using SPSS 26.0.Chi-square test was used to compare the gender differences in different groups,two independent samples T test was used to compare the differences between the diabetes group and the control group,and ANOVA one-way analysis of variance was used to compare multiple groups between different diabetes duration subgroups and the control group.Binary logistic regression was used to analyze the effects of pupil measurement parameters and pupillary analyzer parameters on pupil size after using compound tropicamide for 30 minutes.Generalized estimating equations were used to control binocular correlation,and the correlation between each factor and pupil size after using compound tropicamide for 30 minutes of both eyes was analyzed.Pearson correlation analysis was used to correlate each factor with the pupil size after using compound tropicamide for 30 minutes of the right eye,and the results were visualized using a scatterplot.Results:47 patients with cataract in both eyes were collected,including 24 in the diabetes group and 23 in the control group.The fructosamine concentration in the diabetic group was significantly higher than that in the control group(P = 0.003).There were statistically significant differences in pupil size after using compound tropicamide for 30 minutes(P < 0.001)and mydriasis amplitude(P = 0.005)between the two groups.In the RAPDx examination parameters,the magnitude(P = 0.001),the peak systolic velocity(P =0.001)and the peak diastolic velocity of direct-to-light reflex contraction(P = 0.007),pupil size at baseline in the dark room(P = 0.003)were all significantly different between the two groups.Pairwise comparisons between the two groups with different durations of diabetes and the control group found that some pupil measurement parameters and some pupillary analyzer parameters were statistically different among the three groups.The pupil size after using compound tropicamide for 30 minutes was positively correlated with the direct light reflex contraction amplitude,peak contraction velocity,peak diastolic velocity and the baseline pupil size in the dark room.The pupil size after using compound tropicamide for 30 minutes was also positively correlated with the pupil size before mydriasis and the pupil dilation amplitude.The contraction amplitude,peak contraction velocity,peak diastolic velocity directly related to the light reflex of pupillary analyzer and the dark room baseline pupil size were the protective factors for the pupil larger than 6.5mm group after using compound tropicamide for 30 minutes.Different diabetes duration subgroups were risk factor for pupil larger than6.5mm after using compound tropicamide for 30 minutes.Conclusion:There were statistical differences in some pupillary parameters between the diabetes group and the control group,and between the diabetes subgroups of different durations and the control group.Some parameters were correlated with the pupil size after mydriasis.The pupils of the diabetic group were significantly smaller than those of the control group.