Reza Gharebaghi

Central Corneal Thickness and Intraocular Pressure in Malay Children

Background To determine the mean values for central corneal thickness (CCT) and intraocular pressure (IOP) and the relationship between these values, in healthy Malay children to serve as reference values in diagnosis and treatment. Design A cross-sectional study. Methodology/Principal Findings One hundred and eight eyes (54 subjects) of Malay children without diagnosis of ocular abnormality or disease meeting our inclusion and exclusion criteria were selected. The CCT and IOP were measured by specular microscopy and non-contact air-puff tonometry respectively, for analysis and comparison with the values obtained in previous studies. Mean CCT and IOP was found to be 530.87±30.79 µm and 15.65±3.05 mm Hg respectively. CCT was found not to vary with age. A positive relationship was found between CCT and IOP; specifically, with every 100-µm increase in CCT, IOP increased by 3.5 mm Hg. Conclusions/Significance CCT and IOP are strongly related in healthy Malay children aged 8 to 16. The mean CCT of Malay children is lower than that of majority children of other ethnic groups, supporting the existence of CCT variation among different populations and that ethnicity should be a key consideration when applying CCT data to the general pediatric population.

Nerve fiber layer thickness.

Dear Editor: Anne Marie Lane et al recently reported a study with adjuvant treatment of interferon alfa-2a in 121 patients with choroidal or ciliary body melanoma after proton beam radiation or enucleation. Interferon alfa-2a was administered 3 times per week for a period of 2 years. Eligible for this study were high-risk patients with age 65, largest tumor diameter 15 mm, ciliary body involvement of the tumor, extrascleral tumor extension, and diagnosis within 3 years of study enrollment date. The authors show that interferon alfa-2a had no influence on survival in their patients. In 2006, we published a small pilot study with 39 patients treated with adjuvant interferon alfa 2b, also in a low-dose regimen, over a period of 1 year, which was the standard adjuvant interferon treatment of cutaneous melanoma in Europe at this time. A leading German journal, Der Ophthalmologe, published our study in 2006, despite the fact that our study failed to demonstrate an influence on the survival of our patients. As a consequence of our findings, interferon was terminated as an adjuvant treatment for uveal melanomas at our university. Contrary to the Massachusetts Eye and Ear Infirmary report, we included patients with Ruthenium brachytherapy, Leksell-R-gamma-knife radiosurgery, and transpupillary thermotherapy besides enucleation. The median age in our study was 58 years, whereas it was 63 years in the published manuscript. Median largest tumor diameter in our study was 11.5 mm, whereas it was median 15 mm in Massachusetts report. The side effects observed by Lane et al were similar to ours, but we had 5 serious adverse events including 1 patient with myocardial infarction, 1 patient with ischemic insult, 1 patient with severe depression, and 2 patients with vertigo and headaches. These were viewed as possibly drug-related. Interestingly metastatic disease occurred slightly more frequent in the interferon-treated groups than in the control groups in both studies. We appreciate the above-mentioned study by Lane et al confirming our results in a larger study with a longer followup, thus supporting our decision to terminate interferon treatment for uveal melanomas until the questions of efficacy, safety, dose, and administration are solved.

Palpation by blind examiners: A novel approach for glaucoma screening.

Although there are several risk factors for glaucoma, elevated intraocular pressure (IOP) remains the major risk factor. Palpation is one of the oldest, simplest, and least expensive methods for approximate IOP assessment. Researchers believe that blind individuals may possess a more acutely developed sense of touch, which has already proved to be beneficial in clinical breast examination to detect early breast cancer. Based on successful findings of a project that used blind and visually impaired individuals as breast examiners, we hypothesize that blind individuals may also serve as successful examiners for estimation of IOP using tactile palpation.

Potential use of taurine against pterygium formation.

Dear Editor: Pterygium is a fibrovascular lesion involving the ocular surface and is characterized by proliferation, inflammatory infiltration, fibrosis, angiogenesis, and extracellular matrix breakdown (Fig. 1). The mechanism of pterygium formation remains incompletely understood. Ultraviolet radiation possibly induces ocular surface changes, and in particular, affects stem cells in the corneoscleral limbus. Such changes may be further exacerbated by other environmental factors, such as infection with human papillomavirus or oxidative stress. At the molecular level, alterations in the expression of tumor suppressor genes such as p53, induction of matrix metalloproteinase (MMP), and alterations in the expression of various growth factors are observed. Several treatment modalities, primarily including surgical interventions, for pterygium are available. Because bare sclera excision is associated with a high recurrence rate, pterygium excision is often combined with conjunctival autograft transplantation or mitomycin C therapy, b radiation therapy, or other adjunctive therapies to reduce the recurrence rates. At present, however, there is no consensus regarding the ideal treatment for patients with this disease. On the other hand, it was shown that transforming growth factor-b (TGF-b) was involved in the regulation of many physiologic and pathophysiologic processes. The presence of activated fibroblasts in pterygium tissue is possibly attributable to the actions of TGF-b, given the overexpression of this growth factor in pterygium tissue as compared to that in normal conjunctiva, as previously reported. This would be a good opportunity to introduce new modalities, especially dietary factors that alter the identified genes, and expression of inflammatory and growth factors effective on pterygium formation. Taurine, a sulphur-containing amino acid that has been found to be naturally present in seafood and meat, may play an important role in several essential biologic processes such as development of the central nervous system and retina, membrane stabilization, and immunity. However, data