To evaluate the effect of oral magnesium therapy on ocular blood flow and visual field perimetry indices in patients with normotensive glaucoma (NTG).
Methods
Fifteen patients with NTG (study group) received 300 mg oral magnesium citrate for 1 month, while 15 patients with NTG (control group) received no treatment. Blood magnesium level measurement, visual field analysis, and color Doppler imaging of the orbital vessels were done before treatment and at 1 month.
Results
In the study group, mean deviation improved from −3.7±1.9 (mean ± standard deviation) at baseline to −2.5±1.8 at 1 month (p<0.05), and pattern standard deviation improved from 3.6±2.3 at baseline to 2.8±2.6 at 1 month (p<0.05). Color Doppler imaging indices did not change after magnesium therapy.
Conclusions
Oral magnesium therapy may provide improvement in the visual field, but does not seem to affect ocular blood flow in patients with NTG. Other mechanism than increased ocular blood flow may be responsible for the improvement in the visual field with oral magnesium therapy.
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