Topiramate and asymptomatic ocular angle narrowing: a prospective pilot study.

PURPOSE: To investigate whether subclinical ciliochoroidal effusion and resulting asymptomatic angle narrowing occurs in patients taking topiramate, by ultrasound biomicroscopy (UBM). METHODS: Chinese patients aged 18-75 years for whom topiramate was indicated were recruited. Examinations including UBM were performed before and 4 weeks after commencement of topiramate. RESULTS: In this pilot of 20 eyes of 20 patients, there were no statistically significant changes in the angle parameters noted on gonioscopy or UBM, including anterior chamber depth, angle-opening distance at 500 mum, trabecular ciliary process distance, trabecular-iris angle, and scleral thickness. CONCLUSION: Short-term use of topiramate does not induce asymptomatic angle narrowing.

Correlation of previous acute angle-closure attack with extent of synechial angle closure in chronic primary angle-closure glaucoma patients.

AIM: To document any correlation between previous acute angle-closure attack and the extent of synechial angle closure in chronic primary angle-closure glaucoma (PACG) patients. METHODS: Consecutive cases of chronic PACG with patent peripheral iridotomy had gonioscopy performed. The extents of synechial angle closure of those chronic PACG eyes with previous documented acute angle-closure attack were compared to those eyes without such a history. RESULTS: A total of 102 chronic PACG eyes of 102 patients were recruited. Twenty-seven eyes (26.5%) had a previous documented acute angle closure, while 75 eyes (73.5%) did not. The mean extent of synechial angle closure +/-1 SD was 307+/-68 degrees (range, 150-360 degrees) in those chronic PACG eyes with a history of previous acute angle closure, compared to 266+/-89 degrees (range, 90-360 degrees) in those chronic PACG eyes without such a history (P=0.03, Student's t-test). There were no statistically significant differences between the two groups in age, LogMAR visual acuity, intraocular pressure (IOP), number of glaucoma eye drops, vertical cup-to-disk ratio, mean deviation or pattern SD in Humphrey automated perimetry, and anterior chamber depth (P>0.05). CONCLUSION: Previous acute angle-closure attack correlated with more extensive synechial angle closure in chronic PACG patients in this study.

c-Ha-ras gene mutation and activation precede pathological changes in DMBA-induced in vivo carcinogenesis.

We have previously reported a stage-specific and sequential overexpression of the c-Ha-ras and c-erbB genes in 7, 12-dimethylbenzanthracene (DMBA)-induced in vivo carcinogenesis in hamster buccal pouch epithelium (HBPE). In this investigation, the immunoreactive protein product of the c-Ha-ras gene (p21 protein) was identified in HBPE cells, specifically in treated tissues and cultured cells established after 3 weeks of DMBA treatment. Microscopic examination did not show any histopathological changes in these tissues. The p21 protein was detected in a few selective cells, which were dispersed away from the more densely populated basal layer. The overexpression of the c-Ha-ras gene was accompanied by a point mutation of A----T in codon 61 (CAA), inducing an amino acid substitution from the wild-type glutamine to leucine in the peptide. The concurrent molecular modifications preceded any detectable histopathological changes. The cellular morphology and orientation in treated HBPE at this early stage was indistinguishable from the control tissue. Yet the genetic alterations, such as the point mutation and overexpression of the gene, were evident at the predysplastic stage. Amplification and overexpression of the second proto-oncogene, c-erbB, and its product, epidermal growth factor receptor (EGFR), were detected in HBPE cells at the later stages of extensive cell proliferation and invasion. By using double antibodies and two immunoreporter systems, we demonstrated overexpression of both c-Ha-ras and c-erbB genes in the same HBPE cells during this chemically induced in vivo carcinogenesis.