Abstract
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.
Full text
PDFSelected References
These references are in PubMed. This may not be the complete list of references from this article.
- Binkhorst R. D. Pitfalls in the determination of intraocular lens power without ultrasound. Ophthalmic Surg. 1976 Fall;7(3):69–82. [PubMed] [Google Scholar]
- Clevenger C. E. Clinical prediction versus ultrasound measurement of IOL power. J Am Intraocul Implant Soc. 1978 Oct;4(4):222–224. doi: 10.1016/s0146-2776(78)80100-1. [DOI] [PubMed] [Google Scholar]
- Hillman J. S. The computer calculation of intraocular lens power. A clinical study. Trans Ophthalmol Soc U K. 1980 Apr;100(Pt 1):222–228. [PubMed] [Google Scholar]
- Johns G. E. Clinical evaluation of the DBR A-scan unit. J Am Intraocul Implant Soc. 1979 Jul;5(3):213–216. doi: 10.1016/s0146-2776(79)80113-5. [DOI] [PubMed] [Google Scholar]
- Kraff M. C., Sanders D. R., Lieberman H. L. Determination of intraocular lens power: a comparison with and without ultrasound. Ophthalmic Surg. 1978 Feb;9(1):81–84. [PubMed] [Google Scholar]
- Maloney W. F., Kratz R. P., Mazzocco T. R., Davidson B. Posterior chamber intraocular lens power calculation in 441 cases. J Am Intraocul Implant Soc. 1979 Oct;5(4):349–349. doi: 10.1016/s0146-2776(79)80102-0. [DOI] [PubMed] [Google Scholar]