Comparison Of IOL-Master And Pre-filling A-mode Ultrasound Data In Calculating Silicone Oil Eye Intraocular Lens

Objective: To observe and compare the accuracy of silicone oil intraocular lens(IOL)measured by A-mode ultrasonography before silicone oil filling and IOL-Master,and to understand the characteristics and clinical application of the two methods.Methods: Thirty patients(30 eyes)who underwent phacoemulsification,silicone oil removal and IOL implantation in the ophthalmology department of the First Affiliated Hospital of Guangxi Medical University from January 2018 to March 2019 were retrospectively analyzed.IOL-Master and silicone oil-filled pre-A-ultrasound and corneal curvature meter were used to measure intraocular lenses.The collected data were divided into two groups according to the measurement method: group A was measured by IOL-Master and group B was measured by A-mode ultrasound and corneal curvature meter before silicone oil filling.According to the results of IOL-Master calculation,and according to the refractive state of patients' eyes and their living needs,certain refractive degrees were reserved respectively.For patients without illness or special needs,0.5D myopic diopter was reserved uniformly.All of them were calculated according to SRK.T formula and implanted with IOL.The diopter of one month after operation was analyzed and compared with the expected diopter.The absolute diopter error(MAE)was calculated by refractive results(equivalent spherical diopter for astigmatism)in group A.The difference between IOL measured by A-scan and corneal curvature meter before silicone oil filling and actual IOL implanted in group B was calculated by combining the experimental results.Corneal curvature,eye axis and MAE were compared between the two groups,and the accuracy of the two methods was observed and compared.Result: Axis length: Group A was 23.82(+1.70 mm)and Group B was 23.97(+1.78 mm).There was difference between the two groups.Corneal curvature: 43.96(+1.77D)in group A and 43.85(+1.79D)in group B.There was no significant difference between the two groups.MAE: Group A was 0.61(+0.33D)and Group B was 0.57(+0.55D).There was no significant difference between groups A and B.Conclusion: Both IOL-Master and A-scan data before silicone oil filling can accurately calculate the IOL degree of silicone oil eyes.The two methods have their own advantages and disadvantages in clinical application.It is necessary to select appropriate measurement methods according to the actual situation.