Abstract
Purpose: :
To describe morphologic characteristics associated with secondary IOP elevation due to reverse pupillary block in primary pigment dispersion syndrome (PMDS).
Methods: :
Twenty-two patients with PMDS and ten healthy controls were investigated using anterior segment optical coherence tomography (SL-OCT, Heidelberg Engineering, Germany). Diagnostic criteria for PMDS were the presence of at least 2 of the following clinical signs: retrocorneal pigment deposition, radial iris transillumination, melanin deposition between posterior lens equator and anterior vitreous membrane, dense pigmentation of trabecular meshwork with wide open anterior chamber on gonioscopy. Anterior segment optical coherence tomography (SL-OCT, Heidelberg Engineering, Germany) was performed in patients and controls and used for morphometric analysis. In two patients with proven iris concavity in which Nd:YAG laser iridotomy had been performed, anterior segment optical coherence tomography was performed before and after Nd:YAG laser iridotomy and in medical miosis.
Results: :
In 18 of 22 patients with PMDS a concave iris configuration was detected by SL-OCT. Nevertheless one member of the control group demonstrated mild iris concavity as well. Anterior chamber volume, anterior chamber depth, angle opening distance and trabecular iris space area at distance of 500µm and 750µm from the scleral spur were associated with the degree of iris concavity. A week correlation was found between iris concavity and age (r=-0.34; p<0.05) and refractive error (r=-0.49; p<0.01), but not for maximum IOP values, degree of melanin distribution in the anterior eye segment and morphologic glaucomatous damage. Both patients treated by Nd:YAG laser iridotomy showed improvement or resolution of iris concavity.
Clinical Trial: :
www.clinicaltrials.gov NCT00494923
Keywords: imaging/image analysis: clinical