Laser Peripheral Iridotomy

Stockton / Modesto Laser Peripheral Iridectomy Specialist – Dr. Ash
Also serving Manteca, Tracy, Merced

 Image of an eye treated by Dr. Ash by a Laser Peripheral Iridotomy (LPI) Normally the fluid in the eye is made by the ciliary body and it travels behind the iris and in front of the lens and scape through the pupil to enter the anterior chamber. The fluid then drains through the trabecular meshwork. In cases of the narrow angles, many times there is a relative resistance at the junctions of pupil edge and the lens. This causes some back up of fluid in the space between the iris and the lens (posterior chamber). This build-up can cause the iris to bow forward and further obstruct the angle. Laser can be used to create a hole in the iris and therefore create an "scape hatch" for the fluid and allow the fluid to scape into the anterior chamber via an alternative pathway. This hole then causes equalization of the pressure in the anterior and the posterior chamber and in cases of narrow angles, removes this issue as a contributing factor.
The hole that is created via the laser is called either an iridotomy or an iridectomy. In fact both are correct. In April 2007 at the American Society of Cataract and Refractive Surgery Meeting, Eric Donnenfeld, MD of Long Island, New York was taunting my mentor Roger F. Steinert, MD of Irvine, CA for using the term iridectomy. The lively discussion ended with an impasse, but validates how two giants in ophthalmology can staunchly argue the validity of both terms. The term iridectomy although visualized by many as the old pre-laser days surgical removal of iris tissue, is still valid given that the laser causes release of iris tissue in infinitely small amounts (a "dust"), into the anterior chamber that is eventually absorbed. The Visante OCT clearly shows the swirl pattern of the iris pigment released by the laser in the image on the right. Visante Image of an eye immidiately after LPI by Dr. Ash
Visante Image of an anatomically narrow angle In either case, here is a case of a patient with a narrow angles. She had intermittent headaches in the evening specially when she was in a dark room watching TV. She would experience eye aches and see rainbow colored halos around objects. She also had mild nausea. Her angles pre laser can be noted below.



After discussing the risks, benefits and the alternatives of a laser peripheral iridotomy / iridectomy including possible post-laser spike in pressure (generally very temporary), a small risk of bleeding (generally resolves on its own in few days), and a rare/remote double vision, we proceeded with the laser. Please note how the posterior iris is bowed forward.

 The peripheral laser clearly creates a physical hole (iridotomy or iridectomy) that can be assessed by the Visante OCT for its full patency. Rarely, this opening may not be fully open and may require a second laser procedure to fully open it. Visante Image of the angle  after LPI by Dr. Ash
Visante Image of the angle after the LPI After the laser procedure the patient had complete resolution of all her symptoms before the laser. She had no complications from the laser and her angles opened from a 9.6 degrees pre-op to a 29.2 degrees post laser. Please note how the posterior iris is now completely flat. The Visante OCT was able to help in the pre-operative evaluation, post-laser to confirm patency, and in the post-operative phase to confirm the intended results.


This page was last edited on 07/04/11