Search

Purpose: To correlate aqueous humor soluble CD44 (sCD44) concentration, visual field loss, and glaucoma risk factors in primary open-angle glaucoma (POAG) patients., Methods: Aqueous samples were obtained by paracentesis from normal and glaucoma patients who were undergoing elective surgery and analyzed for sCD44 concentration by enzyme-linked immunosorbent assay., Results: In normal aqueous (n=124) the sCD44 concentration was 5.88+/-0.27 ng/mL, whereas in POAG aqueous (n=90) the sCD44 concentration was 12.76+/-0.66 ng/mL, a 2.2-fold increase (P<0.000001). In POAG patients with prior successful filtration surgery (n=13), the sCD44 concentration was decreased by 43% to 7.32+/-1.44 (P=0.001) in comparison with POAG patients without filtration surgery; however, the sCD44 concentration in the prior successful filtration subgroup with no medications and normal intraocular pressure was 12.62+/-3.81 (P=0.05) compared with normal. The sCD44 concentration of normal pressure glaucoma patients was 9.19+/-1.75 ng/mL, a 1.6-fold increase compared with normal (P=0.02). Race and intraocular pressure pulse amplitude were significant POAG risk factors in this cohort of patients. In both normal and POAG patients with mild and moderate visual field loss, sCD44 concentration was greater in African Americans than in whites (P=0.04)., Conclusions: sCD44 concentration in the aqueous of POAG patients correlated with the severity of visual field loss in all stages in white patients and in mild to moderate stages in African American patients. sCD44 concentration in aqueous is a possible protein biomarker of visual field loss in POAG.

This study tested the hypothesis that (a) evidence of foveal visual dysfunction could be elicited in glaucoma subjects by measuring flicker sensitivity as a function of time after onset of an adapting field for a suitably chosen set of test and adaptation parameters and that (b) such dysfunction would be related to high blood pressure. Three groups of subjects were tested: (a) subjects with primary open-angle glaucoma but only minimal field loss, (b) normal control subjects, and (c) control subjects found to be suspect for glaucoma. The protocol included measurement of pulse rate and blood pressure, administration of Humphrey 30-2 visual fields and optic nerve head photography, and administration of a battery of psychophysical tests in Maxwellian view. This battery included a test of flicker sensitivity measured at middle wavelengths as a dynamic function of time after onset of a long-wavelength adapting field. The dynamic light-adaptation functions of subjects with glaucoma were much more likely to be unstable than were the corresponding functions of normal subjects. In addition, the dynamic light-adaptation functions of subjects with high blood pressure for their pulse rate were significantly less stable than the correspond ing functions of subjects without high blood pressure for their pulse rate. Moreover, the ratio of mean arterial pressure to pulse rate was significantly less for normal subjects than for either glaucoma subjects or for glaucoma-suspect subjects. We infer that among people with primary open-angle glau coma but with only minimal field loss, there often is foveal dysfunction associated with cardiovascular disease. Evidence of such dysfunction appears to require the use of stimulus conditions that tax the ability of the visual system to respond appropriately.

The in vivo response to laser trabeculoplasty (LTP) was evaluated by measuring the incorporation of thymidine into DNA in the nuclei of trabecular meshwork cells. incorporation into DNA was analyzed by light microscopic autoradiography and by scintillation counting of trabecular extracts. Sixteen cats received argon LTP at a power setting of either 0.3 or 1.0 watt with the contralateral eye serving as a control; a 48-h exposure to HT began 1, 5, or 12 days later. The level of HT incorporation into DNA for LTP-treated eyes was significantly higher than controls for the earliest labeling period, but not at the later time points. This pattern was observed for both 0.3-and 1.0-watt treatments. In a second experiment, LTP was performed on six animals; a power setting of 0.3 watt was used in the left eye, and a power setting of 1 watt was used in the right eye. All 12 eyes were radiolabeled for 48 h with HT beginning 1 day after LTP. A small but significant difference in incorporation levels was found between these two power settings. Trabecular cell division may play a role in the therapeutic efficacy of LTP in glaucoma patients.