RESUMO
Purpose: To compare the axial length (AL) obtained by A-scan biometry (PAC SCAN 300AP; Sonomed Escalon, USA) and LENSTAR-LS 900 (Haag-Streit, Koeniz, Switzerland) in silicone oil (SiO)-filled eyes. Methods: AL measurements were taken in 50 SiO-filled eyes using A-scan and LENSTAR-LS 900 before SiO removal and 1 month following SiO removal. In the subset of patients requiring intraocular lens (IOL) insertion, the predicted refraction and the refraction obtained were compared. IOL power in these patients was calculated using SRK-T formula and the AL obtained by LENSTAR. Results: In SiO-filled eyes, a significant difference was noted between the AL values obtained using the two methods (P = 0.0002). No significant difference was noted after SiO removal (P = 0.634). In the subset of patients needing IOL insertion, no significant difference (P = 0.07) was seen between target refractive error and postoperative refractive error (mean deviation from the target being 0.176 diopter). AL of an SiO-filled eye is more accurately measured using optical low coherence reflectometry (OLCR)-based biometry (LENSTAR) than with conventional acoustic biometry (A-scan). Conclusion: We conclude that LENSTAR gives more accurate biometry in an SiO-filled eye. The AL obtained after SiO removal was comparable and showed no significant difference
RESUMO
@#AIM: To explore the postoperative refractive error and influence factors using the Optical Biometry(IOL Master)in patients with silicone oil filled eye complicated cataract after silicone oil removal combined with cataract surgery.<p>METHODS: From August 2020 to November 2020 in the Affiliated Eye Hospital of Nanchang University, 41 patients with silicone oil removal combined with cataract surgery were divided into 2 groups: 18 patients(18 eyes)in high myopia group and 23 patients(23 eyes)in non-high myopia group. Collected and recorded the patients' IOL Master measurement data. Statistical analysis was performed in SPSS20.0.<p>RESULTS: The mean spherical degree or astigmatism of the IOL Master measurement and refraction in high myopia and non-high myopia group performed by paired <i>t</i>-test(<i>P</i>>0.05). The mean axial difference ΔAL were -0.28±0.29 and 0.05±0.31mm between the two groups has no difference(<i>P</i><0.05), while ΔK, mean absolute refractive error(MARE)and Δastigmatism(<i>P</i>>0.05). The preoperative and postoperative axial length(AL)in high myopia groups were 28.37±1.73 and 28.10±1.55mm(<i>t</i>=3.994, <i>P</i><0.05), yet the non-high myopia group(<i>P</i>>0.05). Bivariate linear correlation analysis: in the high myopia group, there was a moderate positive correlation between preoperative AL and MARE(<i>r</i>=0.742, <i>P</i><0.05), and a moderate negative correlation between ΔAL and MARE(<i>r</i>=-0.646, <i>P</i><0.05), but in non-high myopia group, preoperative AL, ΔAL, preoperative K, ΔK had no correlation(<i>P</i>>0.05).<p>CONCLUSION: IOL Master performed the small biostatistical error and high measurement accuracy of the intraocular lens in patients with silicone oil filled eye complicated cataract. The longer preoperative AL, the more changes in the axial length after silicone oil removal, and the greater the refractive error of patients with high myopia silicone oil filled eye complicated cataract.
RESUMO
Background The combination procedure of the removal of silicon oil and cataract extraction+intraocular lens (IOL) implantation is the main method of treating cataract in silicone oil tamponade eye.However,the conventional measuring method of the IOL power is limiting in eyes with silicone oil tamponade.The IOL-Master system is confirmed to be an ideal non-contact optical measuring instrument in vivo.Objective The aim of this study is to measure the preoperative IOL power,evaluate the accuracy of biometry with the IOL-Master system and compare the relationship between different factors and refractive error.Methods IOL power was measured in 29 silicone oil tamponade eyes of 29 patients prior to the silicone oil removal combining IOL implantation with the IOL-Master system according to different factors such as placement time,axis oculi,complications and so on.The reasons of visual acuity recovery and measurement error were discussed.Results Postoperative visual acuity was improved in all of the patients.The average predictive refractive error was 0.329±0.846 (-1.5--2D).Classified factors for the cause of disease for axis oculi included rhegmatogenous retinal detachment (RRD)(t=0.478,P=0.637),macular hole(t=0.135,P=0.895),myopia(t=0.435,P=0.667)and oil-placed time (good for less than 1 year).These factors showed an indirect relationship with errors.Conclusion Silicone oil removal combined with IOL implantation can improve visual acuity.The IOL-Master biometry is accurate,safe and convenient in measuring the IOL power in silicon oil temponade eye,but future research should be performed to decrease the measuring error.