[Effect of negative pressure suction on rabbit optic nerve and retina].

OBJECTIVE

To study the effect of acute intraocular pressure (IOP) elevation on the optic nerve and retina in laser in situ keratomileusis (LASIK).

METHODS

Acute IOP was increased to 65 mm Hg for different period of time (30 s, 1 min and 3 min) by using scleral suction on rabbit eyes. The tissues of retina and optic nerve of immediately extirpated group (instant group), of 2 weeks later extirpated group (recovery group) both after the negative pressure suction and of normal rabbit eyes were examined with electron and light microscope.

RESULTS

After the negative pressure suction for 30 s, 1 min, and 3 min respectively, the optic nerve and retinal cells changed lightly; some part of optic nerve and retinal cells changed; optic nerve fibers and retinal cells changed sharply.

CONCLUSION

Ultrastructural changes of retina and optic nerve may be induced by acute IOP elevation in LASIK. The longer the time, the more apparent the changes.