Capsule contraction after continuous curvilinear capsulorhexis: poly(methyl methacrylate) versus silicone intraocular lenses.
OBJECTIVE
To evaluate the progressive contraction of the anterior capsule opening after in-the-bag implantation of 2 types of intraocular lenses (IOLs).


METHODS
Department of Ophthalmology, University of Brest, Brest, France.


METHODS
In this prospective study, 32 single-piece poly(methyl methacrylate) (PMMA) (Pharmacia 812 C) and 30 3-piece silicone IOLs with PMMA haptics (Allergan SI-40NB) were implanted in the bag after standardized phacoemulsification performed by the same surgeon. All patients were older than 70 years, and none had zonular weakness. The surface of continuous curvilinear capsulorhexis (CCC) was measured 1, 30, and 150 days postoperatively using a 3 charge-coupled device camera and a digitized computer analysis system.


RESULTS
A significant progressive constriction was observed at 150 days in 70% in the silicone group and 32% in the PMMA group. In addition, CCC contraction was greater in silicone group (P < .05). The mean surface decrease was 4.20 mm2 in the silicone group and 1.53 mm2 in the PMMA group. There was no correlation between sex, age, initial capsulorhexis area, final capsule shrinkage. In some eyes, especially in those with a single-piece PMMA IOL (41%), there was no constriction, but fine changes in the capsule opening were seen.


CONCLUSIONS
Evolutive anterior capsulorhexis modifications were observed in all patients; however, the contraction rate was statistically higher in the silicone group. These results suggest that silicone IOL implantation should be avoided in eyes at risk for CCC constriction.
Cochener
B
B
Department of Ophthalmology, University of Brest, France.
Jacq
P L
PL
Colin
J
J
D000368:Aged; D000369:Aged, 80 and over; D019923:Capsulorhexis / Q000009:adverse effects*; D005260:Female; D006801:Humans; D053685:Laser Therapy; D007903:Lens Capsule, Crystalline / Q000473:pathology* / Q000601:surgery; D007905:Lens Diseases / Q000209:etiology* / Q000601:surgery; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular / Q000009:adverse effects*; D008297:Male; D018918:Phacoemulsification; D019904:Polymethyl Methacrylate / Q000009:adverse effects*; D011446:Prospective Studies; D012826:Silicone Elastomers / Q000009:adverse effects*
D012826:Silicone Elastomers; D019904:Polymethyl Methacrylate