Abstract
Purpose :
As has been demonstrated, concentrations of trace elements in the aqueous humor vary in different diseases. According to our previous research, zinc played an important role in glaucomatous neuropathy, indicating the necessity to investigate the changes to the zinc concentration ([Zn]) of the aqueous humor during primary glaucoma and the correlation between such changes and corresponding clinical factors.
Methods :
The aqueous humor and clinical data of 72 primary glaucoma patients and 66 gender-, age-matched cataract controls were collected. Levels of zinc were assayed by FI-ICP-MS. Clinical data (e.g. visual acuity, intraocular pressure, visual field, OCT and medication) was included in regression, correlation and other statistical analysis.
Results :
1. Aqueous humor [Zn] of primary glaucoma patients was 3.75-fold higher than that of controls. The levels of aqueous humor zinc were of moderate value in the prediction of glaucoma, and the threshold was 42.428 μg/L.
2. In subtyping analysis, aqueous humor [Zn] of acute angle-closure crisis (AACC) patients was significantly higher than that of primary angle-closure glaucoma (PACG) and primary open angle glaucoma (POAG) patients. Levels of zinc in the aqueous humor of the three aforementioned types of patients were all significantly higher than that of controls.
3. Aqueous humor [Zn] positively correlated with intraocular pressure (IOP) and increased significantly when IOP was higher than 21mmHg.
4. Correlation analysis illustrated a relationship between ln [Zn] and the total number of glaucomatous drugs use in patients with AACC, PACG or POAG. For PACG patients, ln [Zn] also related to the number of angle-closed quadrants, while the number of RNFL-thinning quadrants was found to be correlated with ln [Zn] in patients with POAG. There was no obvious relationship between ln [Zn] and age, gender or other factors of AACC patients or cataract controls.
Conclusions :
Aqueous humor [Zn] of primary glaucoma patients was remarkably higher than that of controls. The levels were affected by the type of glaucoma and IOP. Subtype analysis illustrated that aqueous humor [Zn] could reflect the severity of glaucoma to some extent.
This is a 2020 ARVO Annual Meeting abstract.