Traumatic Cataract After Inadvertent Laser Discharge

Focal cataract formation may occur after Nd:YAG laser peripheral iridotomy; however, the lenticular opacities are typically small and outside of the visual axis. A 33-year-old man developed a traumatic cataract after spontaneous Nd:YAG laser discharge through the left pupil. A focal defect in the posterior portion of the left lens with subcapsular and cortical opacities necessitated cataract extraction.

A 33-year-old man with a history of myopia and pigment dispersion underwent successful Nd:YAG laser iridotomy in his right eye 3 weeks prior to our seeing him. Best-corrected visual acuity was 20/20 OU and he had normal findings on automated perimetry. On returning for iridotomy in his left eye, prior to placing his forehead against the restraint at the laser-equipped slitlamp, he and the surgeon heard a noise that sounded as if the laser had discharged. The treating physician noted that the safety marker on the laser was illuminated and instructed the patient to place his forehead forward. As the patient was positioning his forehead, he heard a second sound that was accompanied with pain and blurred vision in his left eye. To treat the pain and blurred vision, he was placed on a regimen of 0.2% brimonidine tartrate twice per day and 1% prednisolone acetate every hour in the left eye.

He was seen the following day for neuro-ophthalmic examination because of progressive blurring of vision in his left eye. Best-corrected visual acuity was 20/20 OD and 20/40 OS. Examination of the anterior segment revealed a patent peripheral iridectomy in the 12-o'clock position of the right eye. The left iris was normal, without evidence of a stromal defect. A focal defect within the posterior portion of the lens as well as a subcapsular cataract and a cortical cataract with a rosette configuration were noted in the left lens (Figure 1). There was no evidence of anterior chamber cells or flare and the intraocular pressure was 14 mm Hg OU. There was no relative afferent pupillary defect and findings from the remainder of his neuro-ophthalmic evaluation, including examination of the retina, were normal. The vision in his left eye remained unchanged over the ensuing 4 weeks and he underwent cataract extraction and posterior chamber intraocular lens implantation in the left eye.

The treating physician called the laser manufacturer and was informed that the unit had been moved several days prior to the attempted treatment of this patient's left eye. The laser had been left in the service mode so that the safety/standby feature was still disabled and the spontaneous discharge resulted in a pulse of 6.3 m J through the pupil and thus resulted in the formation of a traumatic cataract.

Cataract formation is a well-recognized complication of laser peripheral iridotomy. The lenticular opacities are focal, adjacent to the iridotomy site, and do not typically cause visual impairment.¹ A study by Wand and coworkers² of 100 patients undergoing iridotomy with the Nd:YAG laser found that only 3 patients required cataract extraction within 1 year, and all 3 had a prior history of catarcts before laser treatment. A perforation cataract has been noted by Wollensak and coworkers³ after successful iridotomy in a patient with pigment dispersion syndrome. However, the patient in their report developed a focal defect within the anterior capsule at the site of the successful iridotomy and the lenticular opacity cleared spontaneously 3 weeks after laser treatment. Unfortunately, our patient's cataract did not clear and he required cataract extraction in the left eye.

Dr Foroozan is supported by the Heed Ophthalmic Foundation, Cleveland, Ohio.

The authors have no proprietary interest in any contents within this article.

We acknowledge Bob Curtin, director of diagnostic photography, Wills Eye Hospital, for the slitlamp photographs.

Corresponding author: Rod Foroozan, MD, Cullen Eye Institute, Baylor College of Medicine, 6565 Fannin NC 205, Houston, TX 77030 (e-mail: foroozan@bcm.tmc.edu).