Biomaterial Database

Experimental implantation of posterior chamber prototype intraocular lenses for the feline eye. 1998

B C Gilger, and M G Davidson, and C M Colitz

Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.

OBJECTIVE To measure postoperative anterior chamber depth (ACD), corneal curvature, and refractive state of feline eyes after lens removal and implantation of a prosthetic intraocular lens (IOL) and determine appropriate IOL use in cats. METHODS 8 clinically normal adult cats. METHODS A-scan ultrasonic biometry, keratometry, and streak retinoscopy were performed on both eyes of each cat before and after lens removal and implantation of a prosthetic IOL. Three diopter (D) IOL strengths were used: 48, 51, and 60 D. Measurements were recorded for 12 weeks after surgery. RESULTS IOL were well tolerated by cats, with no serious complications attributable to implantation or presence of the IOL. The ACD was significantly greater after (8.30 mm) than before (4.97 mm) surgery; however, it became slightly more shallow during the 4 weeks after surgery, suggesting that the IOL shifted anteriorly in the eye. Significant difference in corneal curvature was not detected before or after surgery among eyes with various IOL. Twelve weeks after surgery, eyes with 48-, 51-, and 60-D IOL had mean +/- SD refractive state of +2.1 +/- 0.49, +0.42 +/- 0.20, and -2.6 +/- 0.78 D, respectively. Linear regression analysis of refractive state on IOL power for all eyes at 12 weeks after surgery predicted that +52.8-D IOL was necessary to best approximate emmetropia in these cats. CONCLUSIONS IOL of substantially higher diopter strength than that needed in dogs was required to achieve emmetropia after lens extraction in cats. A 52- to 53-D IOL is required to correct feline eyes to near emmetropia after lens removal.

UI	MeSH Term	Description	Entries
D012029	Refraction, Ocular	Refraction of LIGHT effected by the media of the EYE.	Ocular Refraction,Ocular Refractions,Refractions, Ocular
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D003315	Cornea	The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous CORNEAL EPITHELIUM; BOWMAN MEMBRANE; CORNEAL STROMA; DESCEMET MEMBRANE; and mesenchymal CORNEAL ENDOTHELIUM. It serves as the first refracting medium of the eye. It is structurally continuous with the SCLERA, avascular, receiving its nourishment by permeation through spaces between the lamellae, and is innervated by the ophthalmic division of the TRIGEMINAL NERVE via the ciliary nerves and those of the surrounding conjunctiva which together form plexuses. (Cline et al., Dictionary of Visual Science, 4th ed)	Corneas
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000867	Anterior Chamber	The space in the eye, filled with aqueous humor, bounded anteriorly by the cornea and a small portion of the sclera and posteriorly by a small portion of the ciliary body, the iris, and that part of the crystalline lens which presents through the pupil. (Cline et al., Dictionary of Visual Science, 4th ed, p109)	Anterior Chambers,Chamber, Anterior,Chambers, Anterior
D001699	Biometry	The use of statistical and mathematical methods to analyze biological observations and phenomena.	Biometric Analysis,Biometrics,Analyses, Biometric,Analysis, Biometric,Biometric Analyses
D014463	Ultrasonography	The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1.6 to 10 megahertz.	Echography,Echotomography,Echotomography, Computer,Sonography, Medical,Tomography, Ultrasonic,Ultrasonic Diagnosis,Ultrasonic Imaging,Ultrasonographic Imaging,Computer Echotomography,Diagnosis, Ultrasonic,Diagnostic Ultrasound,Ultrasonic Tomography,Ultrasound Imaging,Diagnoses, Ultrasonic,Diagnostic Ultrasounds,Imaging, Ultrasonic,Imaging, Ultrasonographic,Imaging, Ultrasound,Imagings, Ultrasonographic,Imagings, Ultrasound,Medical Sonography,Ultrasonic Diagnoses,Ultrasonographic Imagings,Ultrasound, Diagnostic,Ultrasounds, Diagnostic
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
D016014	Linear Models	Statistical models in which the value of a parameter for a given value of a factor is assumed to be equal to a + bx, where a and b are constants. The models predict a linear regression.	Linear Regression,Log-Linear Models,Models, Linear,Linear Model,Linear Regressions,Log Linear Models,Log-Linear Model,Model, Linear,Model, Log-Linear,Models, Log-Linear,Regression, Linear,Regressions, Linear