Tip of the month
The Science behind the Tip
Plateau iris configuration is characterised by a closed anterior chamber angle in association with a flat iris plane and a relatively deep central anterior chamber. An anterior position of the ciliary processes results in an abnormal configuration of the peripheral iris (1). Plateau iris syndrome describes acute congestive angle closure which occurs with pupillary dilation despite a patent iridotomy.
Patients tend to be young and less hyperopic than those with primary angle closure caused by a relative pupillary block (2,3). However, as there is often an element of pupillary block in patients with plateau iris configuration, a laser iridotomy should be undertaken. If the IOP is uncontrolled, then pilocarpine 1% or laser iridoplasty should be tried (4).
Contributor: John F Salmon MD - Oxford
1. Pavlin CJ, Ritch R, Foster FS. Ultrasound biomicroscopy in plateau iris syndrome. Am J Ophthalmol 1992; 113: 390-5
2. Ritch R, Chang B, Leibmann J. Angle closure in younger patients. Ophthalmology 2003; 110: 188-9.
3. Stieger R, Kniestedt C, Sutter F, et al. Prevalance of plateau iris syndrome in young patients with recurrent angle closure. Clin Experiment Ophthalmol 2007; 35: 409-413.
4. Ng W, Morgan W. Mechanisms and treatment of primary angle closure: a review. Clin Experiment Ophthalmol 2011; 39: 481-2.