Assessment of the strength of minicapsulorhexes.

PURPOSE

To evaluate the effect of age, size, position, and species on the strength of minicapsulorhexes.

SETTING

Surgical Suite and Laser Laboratory, Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA.

METHODS

Capsulorhexes 0.7 to 2.3 mm in diameter were made centrally or peripherally in 35 eye-bank eyes and 32 rabbit eyes. A custom-made instrument stretched the capsulorhexes until rupture. Load and stretch at rupture were recorded.

RESULTS

Maximum load and stretch were 26.3 mN +/- 20.3 (SD) and 50% +/- 18% for central and 50.8 +/- 20.5 mN and 69% +/- 17% for peripheral capsulorhexes in eye-bank eyes and 19.8 +/- 15.2 mN and 38% +/- 13% for central and 13.5 +/- 9.5 mN and 30% +/- 7% for peripheral capsulorhexes in rabbit eyes. Peripheral capsulorhexes were stronger and more elastic than central capsulorhexes in eye-bank eyes, and maximum load and stretch increased statistically with the capsulorhexis diameter.

CONCLUSIONS

Peripheral minicapsulorhexes were more resistant to rupture than central capsulorhexes in eye-bank eyes, probably because of increased lens capsule thickness at the periphery. An increase in capsulorhexis diameter increased the resistance to rupture.