Neodymium:YAG laser damage of intraocular lenses.

Intraocular lenses (IOLs) suitable for implantation were analyzed for the presence of refractile particles. These were found in lathe-cut and injection-molded lenses from various manufacturers. A YAG laser was focused 2 mm beyond the IOLs in a special test chamber and fired through them. The IOLs were then analyzed for damage. A photographically documented study of six IOLs using Q-switched and mode-locked lasers showed optical breakdown occurring within the IOLs; this was not clearly related to refractile particles. Optical breakdown did not occur in two IOLs with a similar number of refractile particles. Damage was seen with the mode-locked but not with the Q-switched laser. The optical breakdown occurred more frequently at high power (5.0 mJ) than at low power (1.2 mJ).

Topographical anatomy of the ciliary sulcus.

The topography of the ciliary sulcus area in humans was examined by slitlamp biomicroscopy and scanning electron microscopy. Characteristics of this area included the following: the sulcus was angulated anteriorly; the ciliary processes were of unequal length; the zonules did not insert on the tips of the ciliary processes but, instead, inserted slightly posteriorly; the contour of the sulcus area was irregular; bands stretched from the base of the ciliary processes to the posterior surface of the iris, making the sulcus a potential space in some areas of the eye. Effects of this topography on IOL implantation are postulated.