Clinical Features Distinguishing Angle Closure From Pseudoplateau Iris vs. Plateau Iris

Abstract

 

Abstract:

 

To evaluate clinical aspects of patients with the diagnosis of plateau iris (PI) or pseudoplateau iris (PPI) in an ultrasound biomicroscopy (UBM) clinic in order to determine if there are clinical factors that can help differentiate between these two entities. A retrospective review of 76 consecutive UBM patients (152 eyes)with the diagnosis of PI or PPI. The diagnosis of PI was based on an anteriorly positioned ciliary body that abutted the peripheral iris, a narrow (<10 degrees) or closed angle for at least 180 degrees, and the anterior portion of the iris positioned anterior to scleral spur. The diagnosis of PPI was similar to plateau except that large or a cluster of small cysts had to be present in the iridociliary sulcus such that they abutted the peripheral iris. The sample population was 26% male, aged between 26–88 years old, and 93.4% Caucasian. Patients with PPI were more likely to be male, slightly younger, have a ‘bumpy’ peripheral iris appearance, and have less clock hours of gonioscopic angle closure vs. plateau iris patients (see table). Spherical equivalent was not significantly different between groups (1.43D±2.40 PI vs. 0.58D±2.23 PPI; p=0.126).

 

 

^{In patients being referred to a UBM clinic for evaluation of angle closure mechanism, younger males with a bumpy peripheral iris have a higher likelihood of having a diagnosis of pseudoplateau iris. However, clinical factors do not appear to discriminate well between PPI and PI, and UBM is extremely helpful in confirming underlying mechanism and guiding therapy.}

 

 

Keywords: outflow: ciliary muscle • anterior segment