Post-operative changes in the capsulorhexis aperture: a prospective, randomised comparison between loop and plate haptic silicone intraocular lenses.
OBJECTIVE
There is disagreement regarding whether the capsulorhexis aperture always decreases or may increase post-operatively. The aim of this study was to settle the controversy concerning loop haptic silicone lenses and to learn more of the dynamics of the capsulorhexis relating to plate haptic lenses.


METHODS
We performed a prospective randomised study comparing the post-operative changes in capsulorhexis aperture in two groups of eyes implanted with either plate or loop haptic silicone intraocular lenses. All the surgery was performed, at a teaching hospital in the United Kingdom, by a single surgeon, using a standard technique of phacoemulsification. Patients were reviewed at 2 weeks and 6 months post-operatively. Digital retroillumination images of the anterior segment were captured. The area of the capsulorhexis aperture was determined by manually detecting its edge on a computer monitor.


RESULTS
Forty-eight cases were randomised. The groups were comparable for demographic variables and mean initial aperture size (p > 0.05). There was an 8.4% mean decrease in aperture size for the loop haptics, contrasting with 4.5% expansion for the plate haptics (p < 0.05). Sixty-five per cent of patients with the plate haptic underwent enlargement of the aperture, contrasting with 25% for the loop haptic lens (p < 0.05).


CONCLUSIONS
Silicone lenses with plate haptics undergo expansion of the capsulorhexis aperture more frequently than those with Prolene loop haptics.
Patel
C K
CK
Oxford Eye Hospital, Radcliffe Infirmary, UK. ck.patel@utoronto.ca
Ormonde
S
S
Rosen
P
P
Bron
A J
AJ
D000368:Aged; D019923:Capsulorhexis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007910:Lenses, Intraocular; D008297:Male; D018918:Phacoemulsification; D011184:Postoperative Period; D011446:Prospective Studies; D012828:Silicones
D012828:Silicones