Performance indices of 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 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sensitivity % | Specificity % | Sensitivity % | Specificity % | Sensitivity % | Specificity % | ||||||||
| 0% grade | NA | 17.8 | 99.6 | 29.3 | 99.2 | 52.2 | 98.9 | ||||||
| ⩾5% grade | NA | 60.5 | 96.1 | 70.7 | 93.7 | 91.3 | 92.6 | ||||||
| ⩾15% grade | Grade 1 | 83.7 | 85.7 | 84.5 | 82.4 | 91.3 | 81.1 | ||||||
| ⩾25% grade | Grade 2 | 99.2 | 65.5 | 100 | 62.4 | 100 | 61.1 | ||||||
| ⩾40% grade | Grade 3 | 100 | 40.3 | 100 | 38.3 | 100 | 37.5 | ||||||
↵Traditional “van Herick” grades.5
↵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.
↵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.