Optimization of Constant «A» for “Open Bag” Iol «Torsion» Based on Personalized Parameters of the Anterior Segment of the Eye
Abstract
Purpose. To optimize constant «A» (SRK/T formula) for “Open bag” IOL «Torsion» depending on individual parameters of the anterior segment of the eye.
Material and methods. The personalized distance from the corneal surface to the posterior capsule of the lens (PCL) of the eye has been determined as the basis for optimization of constant «A». The postoperative position of the IOL has been analyzed and, taking into account the known value of the average constant «A», the optimized constant «A» has been calculated. A comparative analysis of the refractive error has been performed using the average and optimized constant «A».
Results. Optimized practical constants «A» for ultrasound and optical biometry have been calculated depending on individual eye parameters. A reduction in refractive error has been demonstrated during implantation of the “Torsion” IOL using the optimized constant «A».
Conclusions. Optimized constants «A» were determined for calculating the optical power of the “Torsion” IOL based on personalized values of preoperative values of the distance from the cornea to the posterior capsule of the lens.
The use of the optimized constant «A» allows to reduce the refractive error when calculating the “Open bag” Torsion IOL compared to the use of the average value of the constant «A» for the SRK/T formula.
About the Authors
D. V. Logunov
Пензенский институт усовершенствования врачей – филиал ФГБОУ ДПО «Российская медицинская академия непрерывного профессионального образования»
Russian Federation
Russian Federation
S. L. Kuznetsov
Пензенский институт усовершенствования врачей – филиал ФГБОУ ДПО «Российская медицинская академия непрерывного профессионального образования»
Russian Federation
Russian Federation
A. A. Malikova
Пензенский институт усовершенствования врачей – филиал ФГБОУ ДПО «Российская медицинская академия непрерывного профессионального образования»
Russian Federation
Russian Federation
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Review
For citations:
Logunov D.V., Kuznetsov S.L., Malikova A.A. Optimization of Constant «A» for “Open Bag” Iol «Torsion» Based on Personalized Parameters of the Anterior Segment of the Eye. Bashkortostan Medical Journal. 2025;20(2):55-59. (In Russ.)
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