Cooling prevents induction of corneal damage by argon laser peripheral iridotomy

There are many reports of corneal complications caused by argon laser peripheral iridotomy. In this study, we investigated whether cooling the anterior ocular segment during laser iridotomy prevented corneal damage.

A space for cooling the anterior ocular segment by perfusion with ice-cold water was made between the cornea and a contact lens. Dutch pigmented rabbits were excessively irradiated by an argon green laser, aiming at the peripheral iris. We used a contact lens without a cooling system as a control. Temperature in the anterior chamber and intraocular pressure were also monitored throughout the experiment.

During laser treatment, the temperature without the cooling system rose to a maximum of 44.5 degrees C in the anterior chamber, whereas use of the cooling system consistently kept this temperature at 11.1 degrees -16.1 degrees C. Although most eyes treated without cooling showed corneal damage, damage was seen in only a few or in no eyes cooled during laser treatment.

Argon laser treatment using contact lenses with a cooling system drastically reduced the corneal damage induced by argon laser peripheral iridotomy. This technique may be acceptable for clinical use, considering its technical simplicity and low incidence of treatment-related complications.