The pseudo plateau iris: A review

Pseudo-plateau iris configuration (PPIC) is an under-recognized cause of persistent angle narrowing in the young population, characterized by anterior displacement of the peripheral iris secondary to iridociliary cysts. Although quite common in the general population, occurring in up to half of otherwise normal eyes, only a small subset of ciliary body (CB) cysts produce clinically significant angle compromise. The condition often remains undetected because routine anterior-segment evaluation lacks the ability to visualize the CB, and ultrasound biomicroscopy (UBM) is not universally employed. Clinically, PPIC may present with a "lumpy-bumpy" peripheral iris contour on gonioscopy and incomplete angle opening after laser peripheral iridotomy, raising suspicion for a non-pupillary-block mechanism. Indentation gonioscopy typically reveals appositional rather than synechial closure, reflecting the taut, cyst-supported iris configuration. UBM remains the diagnostic gold standard, demonstrating single or multiple thin-walled cysts, obliteration of the ciliary sulcus, and a deep central anterior chamber with peripheral crowding. Management is individualized and depends on the extent of angle compromise, intraocular pressure status, and cyst morphology. Medical therapy provides temporary pressure control, while laser iridoplasty may relieve focal appositional closure in selected eyes. Cataract extraction deepens the anterior chamber but may not fully address the underlying mechanical obstruction. Filtration procedures are usually needed in advanced cases. Given the discordance between high anatomic prevalence and relatively low glaucomatous conversion, this review focuses on improving recognition, refining diagnostic pathways, and outlining evidence-based management strategies for PPIC.