Comparison Of Preoperative Refraction Measurements In Refractive Surgery: Which Is The Most Reliable Measurement ?
Published 2025 - 43rd Congress of the ESCRS
Reference: PO781 | Type: Free paper | DOI: 10.82333/qhbm-0194
Authors: Edoardo Grosso* 1 , Beatrice Ghezzo 1 , Maria Xeroudaki 2 , Letizia Mansutti 3 , Graziana Maria Ragonese 4 , Rossella Baldini 1 , Moses Kakanga 1 , Emiliano Lepore 1 , Neil Lagali 5
1Recornea srl,Trieste,Italy, 2Eye Clinic, Region Ostergotland,Linkoping,Sweden, 3Blue Eye Centri Oculistici,Milan,Italy, 4Politecnico di Torino,Turin,Italy, 5Dept of Ophthalmology, Linkoping University,Linkoping,Sweden
Purpose
One of the most critical factors in the success of refractive surgery is the accurate determination of preoperative refraction. This study aims to compare the accuracy of different refraction measurements performed before transepithelial photorefractive keratectomy (TPRK) in patients with low to moderate myopia and astigmatism, in order to determine the most reliable measurement for preoperative assessment.
Setting
University of Health Sciences, Beyoglu Eye Training And Research Hospital
Methods
A total of 45 patients(27 females,18 males;90 eyes) with a mean age of 27.29±4.2 years(21–35) were included in the study.In the preoperative period,autorefraction(AR),cycloplegic autorefraction(CAR), eyeglasses prescription(EP) and subjective refraction(SR),were recorded and all values were analyzed as spherical equivalent(SE).For CAR, tropicamide eye drops were instilled three times, and measurements were taken after a 30-minute waiting period.All patients underwent TPRK based on SR.Postoperative refraction measurements were obtained and uncorrected visual acuity(UCVA) and best corrected visual acuity(BCVA) were evaluated preoperative and at the first postoperative month.The differences between AR,CAR,EP and SR were statistically analyzed.
Results
The preoperative mean SE values were -2.85 ± 0.72 D (range: -4.37 to -1.37 D) for AR, -2.46 ± 0.69 D (range: -4.00 to -0.87 D) for CAR, -2.45 ± 0.64 D (range: -3.62 to -0.82 D) for EP and -2.64 ± 0.63 D (range: -4.00 to -1.12 D) for SR. AR measurements generally overestimated myopia, whereas CAR values were closest to SR (p < 0.001). At one month postoperative, the mean AR was -0.14 ± 0.48 D, closely matching the preoperative target. Preoperative UCVA was 0.83 ± 0.32 logMAR, improving significantly to 0.00 ± 0.02 logMAR (p < 0.001). Statistical analysis showed significant differences between AR and SR (p < 0.001), CAR and SR (p = 0.002), and EP and SR (p = 0.007), whereas no significant difference was found between EP and CAR (p = 0.81).
Conclusions
In patients using eyeglasses , EP may serve as a reliable reference for preoperative refraction assessment. AR alone tends to overestimate myopia, while CAR can improve measurement accuracy, particularly in younger patients, by reducing accommodative spasm. For the most accurate preoperative refraction assessment, starting from CAR values and gradually adjusting toward AR values, while incorporating the patient’s habitual EP, may provide the most reliable approach for determining SR.