Comparison of capsular opacification and refractive status after placement of three different intraocular lens implants following phacoemulsification and aspiration of cataracts in dogs.
OBJECTIVE
To evaluate the effect of lens design and biomaterial on formation of posterior capsular opacification (PCO) and refractive correction. Animals studied Sixty dogs undergoing bilateral phacoemulsification for mature or diabetic cataracts.


METHODS
One randomly selected eye received a rounded edge 41D polymethyl-methacrylate (PMMA) intraocular replacement lens (IOL) and the contralateral eye received either a squared edge 41D hydrophilic acrylic IOL (n = 35) or a squared edge 40D hydrophobic acrylic IOL (n = 25). At the (mean = 79 day) reexamination period, PCO was graded using direct slit-lamp observation and by masked observer evaluation of digital images of the IOLs. Streak retinoscopy and B-mode ultrasound were performed at this period.


RESULTS
The PCO score via direct slit-lamp was significantly lower for the hydrophilic acrylic IOL when compared to the PMMA IOL. Masked observer evaluation of digital images revealed that the acrylic IOLs had lower but generally not statistically significant PCO scores than the PMMA IOLs. Streak retinoscopy showed that the PMMA IOL was significantly closer to emmetropia (+0.44 D) when compared to either the hydrophilic acrylic (+0.96 D) or the hydrophobic acrylic (+1.2 D) IOLs. B-mode ultrasonography revealed the center of the hydrophilic acrylic IOL is 0.31 mm closer to the retina and the center of the hydrophobic acrylic IOL is 0.63 mm further from the retina when compared to the center of the PMMA to retina distance.


CONCLUSIONS
Square edged foldable acrylic IOLs show a predisposition towards generating slightly less PCO than round edged PMMA IOLs in the early postoperative period, however, both acrylic IOLs had greater persistent hyperopia than the PMMA IOLs.
Gift
Barrett W
BW
Animal Eye Care Associates, Cary, North Carolina, USA.
English
Robert V
RV
Nadelstein
Brad
B
Weigt
Anne K
AK
Gilger
Brian C
BC
D000180:Acrylic Resins; D000818:Animals; D002386:Cataract / Q000662:veterinary*; D002387:Cataract Extraction / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D004283:Dog Diseases / Q000601:surgery*; D004285:Dogs; D005260:Female; D019654:Lens Implantation, Intraocular / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D008297:Male; D018918:Phacoemulsification / Q000662:veterinary*; D019904:Polymethyl Methacrylate; D011474:Prosthesis Design; D011897:Random Allocation; D016896:Treatment Outcome
D000180:Acrylic Resins; D019904:Polymethyl Methacrylate