Intraocular lens calculation

Autor: Poul Helge Alsbirk, Ernst Goldschmidt, Hans C. Fledelius
Rok vydání: 2009
Předmět:
Zdroj: Acta Ophthalmologica. 65:579-584
ISSN: 1755-375X
DOI: 10.1111/j.1755-3768.1987.tb07044.x
Popis: Intraocular lens power prediction and final astigmatism were evaluated in 100 consecutive cataract patients (age 57-92 years, mainly with intracapsular extraction) 4-13 months after insertion of a 3M type 78 anterior chamber lens. The analysis was based on refractive recordings from the referring ophthalmologists who took care of post-operative controls. Ninety-two patients were accepted for the study. A Sonometrics DBR 400 ultrasound equipment and a Haag-Streit keratometer had been used for measuring eye length and corneal power, the Binkhorst programme and SRK formula for selecting IOL power, resulting in an IOL range of +12 to +23 D. Mainly, low myopia was intended. Nearly 50% fell within 0.5 D from predicted value; 90% were within +/- 1.5 D, by both calculating methods. SRK predictions appeared unaffected by eye size, while axial length (x) significantly influenced Binkhorst prediction (y): y = 8.08-0.35x (r = -0.40), the deviation being most marked in very short eyes. For eyes of midsize the two methods did not differ. Regarding astigmatism, 3 patients ended with values above 3D. In 83% it was less than 2D. Eighty per cent obtained a visual acuity of 0.5 or better. All things considered we feel that the calculation procedure should be standard when performing cataract surgery with IOL implantation.
Databáze: OpenAIRE