Nd:YAG laser iridotomy in pigment dispersion syndrome: an ultrasound biomicroscopic study

Abstract

Aims-Ultrasound biomicroscopy was used to study the shape of the iris and the iridolenticular contact in pigment dispersion syndrome (PDS) eyes, to compare them with matched normal eyes, and to assess the morphological eVects of laser iridotomy in PDS eyes. Methods-50 eyes of 50 patients suVering from PDS (group 1), and 15 normal eyes of 15 subjects matched for age and refraction (group 2), were studied by ultrasound biomicroscopy (UBM, Humphrey-Zeiss). Nd:YAG laser iridotomy was proposed to the 30 PDS patients with concave iris and 18 underwent the treatment. Results-The iris was concave in 27 eyes in group 1, and three more eyes showed a concave iris during accommodation. After laser iridotomy, the treated irises were flatter than normal (p=0.0207), whereas the iridolenticular contact was not significantly diVerent. Conclusions-Laser iridotomy can restore a normal iris shape and iridolenticular contact in eyes suVering from PDS. (Br J Ophthalmol 1998;82:150-153)

A 10-Year Follow-up to Determine the Effect of YAG Laser Iridotomy on the Natural History of Pigment Dispersion Syndrome

“…22(p599) Concurrent abnormalities of the iris, as well as comorbidities and genetic factors, must play a role in facilitating the loss of pigment from the posterior iris surface. 5,23 In our study, 58 of 117 PDS eyes had a positive phenylephrine test result. When left untreated, more than 60% of these eyes showed an increase in IOP of 5 mm Hg or higher during the 10-year follow-up.…”

Effect of neodymium:YAG laser iridotomy on number of aqueous melanin granules in primary pigment dispersion syndrome

“…A number of studies have used ultrasound biomicroscopy to investigate the effect of Nd:YAG laser iridotomy on the configuration of the anterior segment in PDS and have found that iridotomy decreases iris-lens contact [3]; restores normal iris shape [5]; increases the depth of the posterior chamber [14]; prevents iris concavity with accommodation [16]; andcauses iris configuration to remain plain after exercise [11]. Furthermore, a traumatic defect of the peripheral iris appears to protect against development of PDS and PG [21].…”

Infrared Imaging Technique may Help Demonstrate Iris Transillumination Defects in Blacks who Show Other Pigment Dispersion Syndrome Clinical Signs

“…For example, laser iridotomy may have application for some patients in the treatment of classic PDS. [42][43][44][45] Better classification of pigment dispersal syndromes may assist in those subgroups who would most benefit from such procedures.…”