Biomaterial Database

Factors affecting intraocular lens power calculation. 1986

S Longstaff

Department of Ophthalmology, Ninewells Hospital, Dundee.

Intraocular lens power calculation is increasing in use in the United Kingdom. Primarily to avoid anisometropia, intraocular lens power calculation may also be used to provide the patient with three rather than two working distances, but to achieve this greater accuracy of IOL power calculation is required. Using the SRK regression formula, three groups of patients have been studied. The effect of inaccurate use of the formula of choice is shown and the need to modify the 'A' constant to account for variation both in technique and biometry equipment emphasised. The variation in results due to inaccurate biometry are statistically assessed. Accuracy of IOL power calculation requires consistency but not absolute accuracy in biometry. No ocular factors were found to affect the accuracy of IOL power calculation.

UI	MeSH Term	Description	Entries
D007910	Lenses, Intraocular	Artificial implanted lenses.	Implantable Contact Lens,Lens, Intraocular,Contact Lens, Implantable,Intraocular Lens,Intraocular Lenses,Lens, Implantable Contact
D008722	Methods	A series of steps taken in order to conduct research.	Techniques,Methodological Studies,Methodological Study,Procedures,Studies, Methodological,Study, Methodological,Method,Procedure,Technique
D011183	Postoperative Complications	Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.	Complication, Postoperative,Complications, Postoperative,Postoperative Complication
D012030	Refractive Errors	Deviations from the average or standard indices of refraction of the eye through its dioptric or refractive apparatus.	Ametropia,Refractive Disorders,Ametropias,Disorder, Refractive,Disorders, Refractive,Error, Refractive,Errors, Refractive,Refractive Disorder,Refractive Error
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000886	Anthropometry	The technique that deals with the measurement of the size, weight, and proportions of the human or other primate body.
D014792	Visual Acuity	Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.	Acuities, Visual,Acuity, Visual,Visual Acuities
D055095	Optics and Photonics	A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.	Photonics,Photonics and Optics