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AIM:To compare the differences, correlations and consistency of IOL Master 700 or Lenstar LS900 in preoperative ocular biometry and the accuracy of intraocular lens(IOL)degree calculation of cataract patients with high myopia.METHODS: Retrospective study. A total of 136 cases(136 eyes)of high myopia and cataract patients who underwent phacoemulsification at the ophthalmology department of Army Medical Center of PLA from March 2021 to March 2023 were collected, with a mean age of 57.38±8.08 years. Patients were divided into 3 groups based on axial length(AL): 41 eyes in group A(26 mm≤ AL ≤28 mm), 43 eyes in group B(28 mm< AL ≤30 mm)and 52 eyes in group C(AL >30 mm). AL, mean keratometry(Km), anterior chamber depth(ACD), lens thickness(LT)and white-to-white(WTW)were preoperatively measured by two instruments, respectively. Barrett Universal II formula was used to calculate the IOL degrees of all patients, the appropriate reserved diopter was decided individually, and the prediction error(PE)and absolute error(AE)of the two instruments were compared.RESULTS:The AL and ACD of patients in the three groups measured by Lenstar LS900 were higher than the AL measurd by IOL Master 700(all P<0.05), with a difference of AL measured by the two devices: group C>group B>group A. However, there was no statistical significance in LT, Km, and WTW measured by the two instruments(all P>0.05). All biometric parameters measured by the two devices were positively correlated(all r>0.9, P<0.05), and consistent(95% LoA of all groups were narrow). There was no statistically significant difference in AE calculated by the two devices(P>0.05), but the IOL Master 700 calculated a smaller PE than Lenstar LS900(P<0.05), with lower percentage of hyperopic shift in IOL Master 700.CONCLUSION:In cataract patients with high myopia, AL measured by Lenstar LS900 is longer than that by IOL Master 700, and the differences of AL increase along with the growth of AL. Both devices have a good prediction for IOL calculation, but IOL Master 700 has less refractive error, lower percentage of hyperopic shift, and greater clinical advantages IOL Master 700.
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@#AIM: To compare the accuracy of Barrett Universal Ⅱ, Haigis and modified Wang-Koch SRK/T formulas in calculating intraocular lens(IOL)power in eyes with long axial length(AL).<p>METHODS: Eyes were divided into three AL groups as follows: 26.0 to 28.0mm(group A), 28.0 to 30.0mm(group B), and 30.0mm or more(group C). All eyes underwent phacoemulsification cataract surgery. In the 3mo after operation, IOL powers that would have resulted in emmetropia were calculated according to results of subjective refraction. The predictive error(PE)and absolute error(AE)of each formulas were calculated and compared and the factors(AL, keratometry value, the anterior chamber depth)associated with PEs were analyzed.<p>RESULTS: The average PE of Barrett Universal Ⅱ, Haigis and modified Wang-Koch SRK/T formulas were 0.37±0.78D, 0.77±0.88D and 0.36±0.82D respectively. In groups A and B, the PEs and AEs of three formulas were not statistically significant(<i>P</i>>0.05). However, in group C, the PEs and AEs of Barrett Universal Ⅱ and modified Wang-Koch SRK/T formula were significantly less than Haigis formula(<i>P</i><0.05). The PEs of Haigis formula in cataract eyes with long AL was affected by AL and keratometry value, whereas the PEs of Barrett Universal Ⅱ and modified Wang-Koch SRK/T formula was not affected by AL.<p>CONCLUSION: In eyes with an AL of 26.0 to 30.0mm, all three formulas are acceptable. In eyes with AL of 30.0mm or more, the accuracy of Barrett Universal Ⅱ and modified Wang-Koch SRK/T formula are better than Haigis formula.