Positive and negative predictive values of the test for limbal chamber depth estimation in detection of gonioscopically occludable angles, primary angle closure, and primary angle closure glaucoma
| Limbal chamber depth | Traditional grade | All occludable angles | Primary angle closure with or without glaucoma | Primary angle closure glaucoma | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PPVT % | NPVT % | PPVT % | NPVT % | PPVT % | NPVT % | ||||||||
| 0% grade | NA | 76.4 | 94.3 | 57.0 | 97.5 | 27.7 | 99.6 | ||||||
| ⩾5% grade | NA | 53.1 | 97.1 | 28.9 | 98.9 | 9.0 | 99.9 | ||||||
| ⩾15% grade | Grade 1 | 29.9 | 98.6 | 14.8 | 99.3 | 3.7 | 99.9 | ||||||
| ⩾25% grade | Grade 2 | 17.3 | 99.9 | 8.8 | 100 | 2.0 | 100 | ||||||
| ⩾40% grade | Grade 3 | 10.8 | 100 | 5.5 | 100 | 1.3 | 100 | ||||||
↵Prevalence 6.8%.
↵Primary angle closure, those subjects with angles judged to be occludable on gonioscopic examination with either elevated intraocular pressure, peripheral anterior synechiae or a positive dark room, prone provocation test with or without glaucoma. Prevalence 3.5%.
↵Primary angle closure glaucoma, those subjects with an occludable drainage angle and glaucomatous optic neuropathy, corroborated by visual field evidence in mild or moderate cases. Prevalence 0.8%.