Comparison of Serum Homocysteine, Vitamin B12, Vitamin B6 and Folate Levels in Different Glaucoma Types

PURPOSE: To compare the levels of serum homocysteine, vitamin B12, vitamin B6 and folate in patients with normal-tension glaucoma, pseudoexfoliation glaucoma and high-tension glaucoma. METHODS: Thirty-two healthy subjects, 35 patients with normal-tension glaucoma, 22 patients with pseudoexfoliation glaucoma and 31 patients with high-tension glaucoma were included in the present study. Fasting venous samples were collected from all the participants. The levels of serum homocysteine, vitamin B12, vitamin B6 and folate were measured. One-way analysis of variance was used for the comparison of homocysteine, vitamin B12, vitamin B6 and folate levels among the 4 groups. RESULTS: The mean homocysteine levels in the pseudoexfoliation glaucoma and high-tension glaucoma group were 17.91 +/- 5.11 and 17.60 +/- 3.89 micromol/l, respectively, which were significantly higher than that of the control group (p = 0.014, p = 0.013, respectively). The mean vitamin B6 levels in the pseudoexfoliation glaucoma and high-tension glaucoma group were 17.67 +/- 14.32 and 17.00 +/- 10.58 nmol/l, respectively, which were significantly lower than that of the control group (p = 0.026, p = 0.008, respectively). CONCLUSIONS: Hyperhomocysteinemia may play a role as a risk factor in the development or progression of pseudoexfoliation glaucoma and high-tension glaucoma.

A Case of Cataract after Long-Term Use of Clonazepam in a Young Patient

PURPOSE: To report a case of cataract after long-term use of clonazepam in a young patient, with a similar appearance to cataract induced by other psychotropic agents. CASE SUMMARY: A 37-year-old woman complained of a visual disturbance in both eyes. The best-corrected visual acuity was 0.8 in the right eye and 0.6 in the left eye. Bilateral cortical cataract was observed on slit-lamp examination, and no other ophthalmic abnormalities were found. Potential risk factors for cataract were investigated, including past medical and family history, revealing a 20-year history of oral clonazepam (0.5-1 mg/day), for the neurological diagnosis of "chorea of unknown etiology". Detailed medication history did not reveal long-term use of any other drugs which could have induced the cataract. CONCLUSIONS: Because clonazepam use may induce cortical cataract, regular ophthalmologic examinations are necessary during long-term oral psychotropic therapy.