INTRAOPERATIVE SEMIQUANTITATIVE KERATOMETRY USING THE KERATOSCOPIC ASTIGMATIC RULER

Citation
N. Morlet et Pa. Lindsay, INTRAOPERATIVE SEMIQUANTITATIVE KERATOMETRY USING THE KERATOSCOPIC ASTIGMATIC RULER, Journal of cataract and refractive surgery, 21(6), 1995, pp. 616-619
Citations number
NO
Categorie Soggetti
Surgery,Ophthalmology
ISSN journal
08863350
Volume
21
Issue
6
Year of publication
1995
Pages
616 - 619
Database
ISI
SICI code
0886-3350(1995)21:6<616:ISKUTK>2.0.ZU;2-E
Abstract
Intraoperative keratometry enables the surgeon to set an appropriate a mount of corneal astigmatism with the suture tension. Errors in estima ting or measuring the astigmatism can occur with hand-held keratometer s because the distance an object is held from an astigmatic cornea inf luences the shape of the elliptical image. Thus hand-held instruments should be held at a calibrated distance, We have designed a new hand-h eld keratometer, the keratoscopic astigmatic ruler, to assess the magn itude of corneal astigmatism. It consists of a rack of elliptical kera toscopic lenses corresponding to increasing magnitudes of astigmatism and is made from inexpensive autoclavable injection-molded plastic. Th e ruler's keratoscopic lenses refract light, creating a real aerial im age above the cornea that produces a bright and easily determined corn eal reflection. The ruler incorporates a sight to allow the user to ho ld the ruler at the correct distance.