A Method to Improve the Accuracy of Optimized A-Constant for IOL Calculation Formulas
| Autor: | Lei Zheng, John C Merriam |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
medicine.medical_specialty
genetic structures Corneal curvature Keratometer business.industry medicine.medical_treatment Intraocular lens Phacoemulsification Axial length eye diseases Standard deviation law.invention 03 medical and health sciences 0302 clinical medicine law Refractive surgery Ophthalmology 030221 ophthalmology & optometry medicine sense organs business Constant (mathematics) 030217 neurology & neurosurgery |
| Zdroj: | Journal of Clinical & Experimental Ophthalmology. |
| ISSN: | 2155-9570 |
| Popis: | Objective: To achieve more accurate IOL calculation results using multiple A-constants for SRK/T formula. Methods: This is a retrospective clinical study. The study includes 650 cases of phacoemulsification with an Acrysof SN60WF IOL (Alcon, TX). The study excluded eyes that had corneal refractive surgery, eyes with any condition that precluded accurate and consistent keratometry. The study used the average of 5 valid measurements of axial length (AL) and corneal curvature using IOLMaster (Carl Zeiss Meditec, Inc. Germany) prior to surgery and manifest refraction measured at least 3 months after surgery. Patients were divided into 7 groups based on AL from less than 22 mm to greater than 27 mm. The average A-constant with standard deviation was calculated in each group, and these groups were compared to each other using independent two-sample t-test (p |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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