Intraocular lens power calculation for emmetropia: a clinical study.
نویسنده
چکیده
A series of 50 eyes received an intraocular lens (IOL) of power calculated for emmetropia from data of axial length, corneal curvature, and postoperative anterior chamber depth by R. D. Binkhorst's formulae. The postoperative refraction results were compared with those of 100 control eyes which received +19 D standard power IOLs without calculation. The calculated group had postoperative refractions which were closer to emmetropia, and the difference was os statistical significance, with 92% within the +/- 1D range and 98% within the +/- 2 D range from emmetropia. The calculated predictions of postoperative refraction were of a useful level of accuracy. Consideration of the sources of error indicates that there is no justification for the use of IOLs in power steps of less than 1 D. The calculation of IOL power allows the surgeon to control the postoperative refraction and avoid unwanted ametropia.
منابع مشابه
Comparison of intraocular lens power calculation using the Binkhorst and SRK formulae: a clinical study.
Comparison of results of intraocular lens implants with IOL powers obtained by Binkhorst and SRK Linear Regression formulae was done using various models and brands of intraocular lenses. Of 887 pseudophakic patients. 415 patients received IOL's with their powers calculated for planned emmetropia, by means of theoretic formula devised by R.D. Binkhorst and in the remaining 472 eyes the IOL powe...
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Present-day implant lenses are esssentially thick lens systems. The usual methods by which the required power is assessed involve treating them as thin lens systems, thus giving rise to error. It is possible to avoid such an error by changing the approach to the problem. No attempt need be made to calculate the equivalent power of the implant lens required to produce emmetropia after implantati...
متن کاملIntraocular Lens Power Calculation after Corneal Refractive Surgery
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Sixty-five patients underwent intracapsular cataract extraction with implantation of Binkhorst iris-clip intraocular lenses (IOLs). For 31 patients the IOL was of a standard power. Thirty-four patients had axial length measurement and keratometry preoperatively, and IOLs calculated to produce emmetropia or 1 dioptre of myopia were implanted. There was no significant difference in the range of p...
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ورودعنوان ژورنال:
- The British journal of ophthalmology
دوره 66 1 شماره
صفحات -
تاریخ انتشار 1982