Purpose A narrow iridocorneal angle (ICA) is a risk factor for glaucoma progression. However, many patients treated for primary open angle glaucoma (POAG) have never been assessed with dynamic gonioscopy. In this study, we performed dynamic gonioscopy in patients referred for progressing POAG and suspicion of glaucoma (GS) to evaluate the rate of misdiagnosed narrow ICA.
Methods We retrospectively analysed the clinical data of consecutive glaucoma or GS patients referred for evaluation from November 2009 to October 2010. All patients had been previously diagnosed with open ICA. Patients were examined by a single ophthalmologist. The evaluation included detailed medical history, comprehensive ophthalmologic examination, diurnal hourly monitoring of the intraocular pressure, static automated perimetry, retinal nerve fiber layer thickness analysis, central pachymetry and dynamic gonioscopy (Possner® lens).
Results 135 patients were included. The mean age was 53.6 years (+/- 6.2 years). Prior to our evaluation, glaucoma and GS patients had been followed 5.2 years (+/- 3.4 years) with an average of 4.2 visits and 2.2 visual fields. 58 patients (43%) had never undergone gonioscopy. A narrow angle was diagnosed in 18 patients (13.3%), including 5 patients with plateau-iris configuration confirmed by ultrasonic biomicroscopy (27.7% of narrow angles).
Conclusion A narrow ICA is not a rare finding among patients diagnosed with POAG or GS patients. Dynamic gonioscopy should be performed systematically for all glaucoma and glaucoma suspect patients, especially in cases of glaucoma progression despite an efficient and well conducted treatment. Lens size evolution with time requires repeated evaluations.