A Novel Argon Laser Iridoplasty for Pigment Dispersion Syndrome

Pigment dispersion syndrome is a rare condition where anomalous iris configuration leads to posterior iris bowing with subsequent friction with the lenticulozonular unit resulting in dispersion of pigment from the back surface of the iris into the anterior segment as well as thinning with resultant transillumination defects in the mid iris segment. The released pigment is deposited in various parts of the anterior segment resulting in a constellation of clinical signs:

Krukenberg Spindle: Back surface of the cornea Zentmayer ring: Back surface of the lens. Egger line: Anterior vitreous face. More importantly, pigment accumulated in the trabecular meshwork leading to visible hyperpigmentation of the trabeculum seen by gonioscopy. This leads to reduction of aqueous outflow which leads to ocular hypertension or even glaucoma which is known as pigment dispersion glaucoma which is considered one of refractory glaucomas.

Current practice in the management of pigment dispersion syndrome revolves around the management of glaucoma when it develops by IOP lowering medication, Laser trabeculoplasty or peripheral iridoplastyor glaucoma surgery as a last resort. The only prophylactic measure in practice that is aimed at preventing the progression from mere pigment dispersion to pigment dispersion glaucoma is the long term use of miotic eyedrops e.g. Pilocarpine which comes with both risks and side effects i.e. the risk of retinal breaks and detachment which is even higher in a cohort which is predominantly myope, the constriction of visual field and ocular surface complications.

In this interventional case series, the investigators assess the efficacy of a novel Argon Laser iridoplasty in the management of pigment dispersion through correcting the posterior iris bowing and hence halting the dispersion process so that glaucoma wouldn't develop in the first place instead of managing glaucoma after it sets in which proved refractory.