Laser peripheral iridotomy and iridoplasty

Published on 08/03/2015 by admin

Filed under Opthalmology

Last modified 08/03/2015

Print this page

rate 1 star rate 2 star rate 3 star rate 4 star rate 5 star
Your rating: none, Average: 0 (0 votes)

This article have been viewed 3050 times

CHAPTER 44 Laser peripheral iridotomy and iridoplasty

Laser peripheral iridotomy

The continuous wave argon laser revolutionized the treatment of glaucoma. In 1973, Beckman and Sugar reported successful argon laser iridotomies in humans1. Others soon reported success in human eyes with angle closure2. The ease and convenience of the procedure for both patient and surgeon and the paucity of severe complications led to its rapid acceptance. ALPI was first described in 19823.

Indications

LPI is the procedure of choice for all forms of angle closure in which there is a component of pupillary block.

Surgical techniques

The various techniques for LPI as developed in the late 1970s and early 1980s, with multiple variations, are detailed elsewhere9. We describe our current most commonly used techniques and settings.

Contact lenses for laser procedures

Firm control of the contact lens reduces saccades and extraneous eye movements that interfere with accurate superimposition of burns. The lens helps to separate the lids, to focus the laser beam, and to minimize loss of laser power from reflection. By absorbing heat delivered through the cornea, the gonioscopy solution decreases the incidence of corneal burns.

The Abraham lens (Fig. 44.1) consists of a fundus lens with an anterior +66 diopter planoconvex button. The button magnifies without loss of depth of focus. The effective size of a 50 µm spot is reduced to approximately 30 µm; this provides higher energy per unit area and permits the procedure to require a lower total energy. Posterior to the site of focus, the beam is more rapidly defocused, decreasing potential injury to structures behind.

image

Fig. 44.1 Abraham laser contact lens – useful for both laser peripheral iridotomy and laser peripheral iridoplasty.

From Ritch R, Solomon IS. Glaucoma Surgery. In: L’Esperance FA, editor. Ophthalmic Lasers. 3rd ed. St. Louis: CV Mosby Co; 1988. p. 650-748.

Argon laser peripheral iridotomy

Contraction burn
Buy Membership for Opthalmology Category to continue reading. Learn more here