Phacoemulsification and implantation of foldable +14 diopter intraocular lenses in five mature horses.

The research paper revolves around the successful application of phacoemulsification (a modern cataract surgery) and implantation of +14 diopter intraocular lenses in horses with severe farsightedness resulting from spontaneous cataracts. The procedure markedly improved their visual acuity, thereby significantly mitigating their farsightedness (hyperopia), a common post-operative complication in these animals.

Study Design and Procedure

• The researchers selected five mature horses suffering from spontaneous cataracts for the study.
• Each of the selected horses underwent phacoemulsification, and a +14 diopter (D) foldable intraocular lens (IOL) was implanted in their eyes. In total, six eyes were treated as one horse required treatment in both eyes.
• Post-operative ocular examinations occurred at 1, 4, and 24 weeks to assess the outcomes and complications if any.
• The researchers recorded refractive errors (deviation in focusing light) at four weeks post-operation, and visual status, refractive error, and anterior chamber depth at 24 weeks after the surgical procedure.

Results

• Five of the six operated eyes remained functional with an average refractive error of +0.4 ± 1.1D. This significant feature outlines the operation’s effectiveness.
• There was a noted statistical difference between the 24-week post-operative refractive error and the population mean of +10D for horses with absent lens (aphakic).
• The average depth of the anterior chamber, the front part of the eye where fluids circulate, was 7.89 ± 1.55 mm.
• One case required the removal of the eye (enucleation) two months after the operation. This depicts a potential risk tied to lens implantation procedures in horses that should be explored further.

Conclusions

• The researchers concluded that phacoemulsification coupled with IOL implantation significantly reduced post-operative refractive error, bringing the vision close to a natural state (emmetropia) in five out of six operated eyes. This operation could dramatically improve the post-operative visual acuity in horses treated for cataracts.
• The implantation of a +14D IOL successfully countered the hyperopia commonly observed in aphakic horses, paving the way for better quality of life for these animals after cataract surgery.