Acute elevations of intraocular pressure following Nd:YAG laser posterior capsulotomy.

We performed applanation tonometry preoperatively, hourly for the first four postoperative hours and on the first postoperative day in 66 eyes after Nd:YAG laser posterior capsulotomy in order to determine the nature of the acute intraocular pressure (IOP) elevation and the risk factors involved. Forty-one percent of eyes developed an intraocular pressure greater than 30 mmHg and 14% greater than 40 mmHg. The IOP spike occurred on the second postoperative hour in 35% of eyes. Patients with controlled glaucoma prior to capsulotomy had a significantly lower mean IOP rise than patients without glaucoma. Eyes with posterior chamber IOLs were less likely to develop an IOP greater than 30 mmHg than were aphakic eyes without IOLs. There was no correlation between the laser energy or the size of the capsulotomy and the IOP rise.