advertisement
Editors Selection IGR 9-4
Clinical Forms of Glaucoma: The iris in Pigment Dispersion Syndrome by AS-OCT
Comment by Jeffrey Liebmann on:
27925 The concave iris in pigment dispersion syndrome, Liu L; Ong EL; Crowston J, Ophthalmology, 2011; 118: 66-70
Liu, Ong, and Crowston (268) used non-contact, anterior segment optical coherence tomography to explore the anatomy and physiology of iris configuration and movement in pigment dispersion syndrome. The iris anatomy was examined under normal room lighting conditions, following administration of pilocarpine 2% to induce miosis, and with -3.00 and -6.00 diopter lenses to provoke accommodation.
The authors demonstrate, consistent with previous reports, that the iris in pigment dispersion syndrome has a posteriorly concave configuration that increases or can be restored with accommodation and assumes a planar configuration with miotic therapy. Contrary to earlier reports assessing iris configuration by clinical examination and ultrasound biomicroscopy, the authors did not demonstrate any effect of blinking on iris configuration. They suggest that the concave configuration is created and maintained by accommodation rather than any significant contribution by eyelid movement. The authors' hypothesis could be further tested in several ways. First, almost all patients with pigment dispersion syndrome are myopes, and in the resting state without refractive correction, are unlikely to be accommodating. If the iris is concave in this setting, then accommodation may not be the sole cause of the concave configuration. It also might be worthwhile to repeat this experiment using a different fixation target as it could be uncertain as to how much accommodation is generated by the fixation target in the Visante system and by the placement of negative lenses between the target and the patient. It would also be worthwhile to reassess iris configuration at the slit lamp, possibly using a recording system, while fixation and accommodation are altered the fellow eye. Lastly, if the concave iris depends only on accommodation, we should rarely see a concave configuration in presbyopic individuals.
The findings of the current paper will hopefully provoke more investigation into the unusual clinical features of this interesting disorder.
Comments
The comment section on the IGR website is restricted to WGA#One members only. Please log-in through your WGA#One account to continue.Log-in through WGA#One
