Refractive state of aphakic and pseudophakic eyes of dogs

M. G. Davidson From the Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606 (Davidson, Nasisse, Hellkamp, Olivero, Brinkmann), the Department of Surgical Sciences, College of Veterinary Medicine, University of Wisconsin, Madison, WI 53706 (Murphy), and The Animal Eye Clinic, Menlo Park, CA 94025 (Campbell).

Search for other papers by M. G. Davidson in
Current site
Google Scholar
PubMed
Close
 DVM
,
C. J. Murphy From the Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606 (Davidson, Nasisse, Hellkamp, Olivero, Brinkmann), the Department of Surgical Sciences, College of Veterinary Medicine, University of Wisconsin, Madison, WI 53706 (Murphy), and The Animal Eye Clinic, Menlo Park, CA 94025 (Campbell).

Search for other papers by C. J. Murphy in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
M. P. Nasisse From the Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606 (Davidson, Nasisse, Hellkamp, Olivero, Brinkmann), the Department of Surgical Sciences, College of Veterinary Medicine, University of Wisconsin, Madison, WI 53706 (Murphy), and The Animal Eye Clinic, Menlo Park, CA 94025 (Campbell).

Search for other papers by M. P. Nasisse in
Current site
Google Scholar
PubMed
Close
 DVM
,
A. S. Hellkamp From the Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606 (Davidson, Nasisse, Hellkamp, Olivero, Brinkmann), the Department of Surgical Sciences, College of Veterinary Medicine, University of Wisconsin, Madison, WI 53706 (Murphy), and The Animal Eye Clinic, Menlo Park, CA 94025 (Campbell).

Search for other papers by A. S. Hellkamp in
Current site
Google Scholar
PubMed
Close
 MS
,
D. K. Olivero From the Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606 (Davidson, Nasisse, Hellkamp, Olivero, Brinkmann), the Department of Surgical Sciences, College of Veterinary Medicine, University of Wisconsin, Madison, WI 53706 (Murphy), and The Animal Eye Clinic, Menlo Park, CA 94025 (Campbell).

Search for other papers by D. K. Olivero in
Current site
Google Scholar
PubMed
Close
 DVM
,
M. C. Brinkmann From the Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606 (Davidson, Nasisse, Hellkamp, Olivero, Brinkmann), the Department of Surgical Sciences, College of Veterinary Medicine, University of Wisconsin, Madison, WI 53706 (Murphy), and The Animal Eye Clinic, Menlo Park, CA 94025 (Campbell).

Search for other papers by M. C. Brinkmann in
Current site
Google Scholar
PubMed
Close
 DVM
, and
L. H. Campbell From the Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606 (Davidson, Nasisse, Hellkamp, Olivero, Brinkmann), the Department of Surgical Sciences, College of Veterinary Medicine, University of Wisconsin, Madison, WI 53706 (Murphy), and The Animal Eye Clinic, Menlo Park, CA 94025 (Campbell).

Search for other papers by L. H. Campbell in
Current site
Google Scholar
PubMed
Close
 DVM

Click on author name to view affiliation information

SUMMARY

Streak retinoscopy was performed by 5 ophthalmologists on 256 eyes (191 dogs) to determine their postoperative refractive state after cataract extraction. Aphakic and pseudophakic eyes that had been implanted with 1 of 5 intraocular lenses (iol) with dioptric powers ranging from + 14.5 to + 38 diopters (D) were studied. By use of ANOVA, breed and body type of dog and individual performing refraction were found to have no detectable effect on final refractive state. Mean refractive state of aphakic eyes was +14.4 ± 2.10 D. Mean refractive state for different iol powers was as follows: + 14.5 D iol = + 11.54 ± 1.18 D (n = 13); +30 D iol = + 5.15 ± 1.18 D (n = 105); + 34.0 D iol = +3.5 D (n = 1); +36 D iol = +2.34 ± 0.73 D 9 (n = 61); and +38 D iol = + 1.41 ± 0.56 D (n = 28). Residual hyperopia ranged from +0.5 D to +2.5 D with +38 D iol, and no eyes were myopic (overcorrected) by use of any of the iol studied. Linear regression analysis of refractive state on iol power for all dogs predicted that dioptric strength of +41.53 D was necessary to best approximate emmetropia for the population as a whole. Body type of the dog had only slight effect (< 1.0 D) on predicted optimal iol power. Further linear regression analysis of the 7 breeds studied predicted variations from +39.62 to +43.14 D in iol powers necessary to approximate emmetropia. Results of the study support the routine use of canine iol with dioptric strength of approximately + 41.5 D in circumstances in which preoperative biometry and keratometry are not practical. The findings further suggest that, for the specific population of dogs studied, most of the dogs could be corrected to near emmetropia by use of a small range of iol dioptric strengths, irrespective of body type or breed.

SUMMARY

Streak retinoscopy was performed by 5 ophthalmologists on 256 eyes (191 dogs) to determine their postoperative refractive state after cataract extraction. Aphakic and pseudophakic eyes that had been implanted with 1 of 5 intraocular lenses (iol) with dioptric powers ranging from + 14.5 to + 38 diopters (D) were studied. By use of ANOVA, breed and body type of dog and individual performing refraction were found to have no detectable effect on final refractive state. Mean refractive state of aphakic eyes was +14.4 ± 2.10 D. Mean refractive state for different iol powers was as follows: + 14.5 D iol = + 11.54 ± 1.18 D (n = 13); +30 D iol = + 5.15 ± 1.18 D (n = 105); + 34.0 D iol = +3.5 D (n = 1); +36 D iol = +2.34 ± 0.73 D 9 (n = 61); and +38 D iol = + 1.41 ± 0.56 D (n = 28). Residual hyperopia ranged from +0.5 D to +2.5 D with +38 D iol, and no eyes were myopic (overcorrected) by use of any of the iol studied. Linear regression analysis of refractive state on iol power for all dogs predicted that dioptric strength of +41.53 D was necessary to best approximate emmetropia for the population as a whole. Body type of the dog had only slight effect (< 1.0 D) on predicted optimal iol power. Further linear regression analysis of the 7 breeds studied predicted variations from +39.62 to +43.14 D in iol powers necessary to approximate emmetropia. Results of the study support the routine use of canine iol with dioptric strength of approximately + 41.5 D in circumstances in which preoperative biometry and keratometry are not practical. The findings further suggest that, for the specific population of dogs studied, most of the dogs could be corrected to near emmetropia by use of a small range of iol dioptric strengths, irrespective of body type or breed.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 97 97 24
PDF Downloads 41 41 7
Advertisement