ENVIRONMENTAL SCIENCE. Profiling risk and sustainability in coastal deltas of the world.

Deltas are highly sensitive to increasing risks arising from local human activities, land subsidence, regional water management, global sea-level rise, and climate extremes. We quantified changing flood risk due to extreme events using an integrated set of global environmental, geophysical, and social indicators. Although risks are distributed across all levels of economic development, wealthy countries effectively limit their present-day threat by gross domestic product-enabled infrastructure and coastal defense investments. In an energy-constrained future, such protections will probably prove to be unsustainable, raising relative risks by four to eight times in the Mississippi and Rhine deltas and by one-and-a-half to four times in the Chao Phraya and Yangtze deltas. The current emphasis on short-term solutions for the world's deltas will greatly constrain options for designing sustainable solutions in the long term.

Intraocular pressure during haemodialysis: a review.

OBJECTIVES: Although several works in the past have examined the effect of haemodialysis (HD) on intraocular pressure (IOP), reported findings, theories, and conclusions are very different. The objectives of this article are to resume the reported evidence of IOP changes during HD, to review the proposed hypothesis of HD influence on IOP, and to determine if ophthalmic examination is imperative in HD patients. METHODS: We analysed the peer-reviewed English literature and selected all possible relevant articles. RESULTS: The influence of HD on IOP is not clear, and even in recent studies opposite findings can be found. CONCLUSIONS: Future studies are needed to clarify the effects of HD on IOP. In patients with glaucoma or with predisposed narrow angles, or eyes with impaired aqueous outflow, the possibility of acute IOP rise during HD could be much more frequent than in normal patients. So in these patients, a more strict ophthalmic scheduled examination seems to be feasible.

Toxic effects of subconjunctival 5-fluorouracil and mitomycin C on ciliary body of rats.

PURPOSE: The effects of subconjunctival injection of mitomycin C and different concentrations of 5-fluorouracil on the epithelium of the ciliary body of twenty Sprague Dawley SD rats was studied. METHODS: Twenty rats were divided into four treatment groups. The first three groups received 0.2 ml of 5, 10, and 30 mg of 5-fluorouracil subconjunctivally respectively, and the fourth group 0.2 ml of 0.4 mg/ml mitomycin C subconjunctivally. The right eye received 0.2 ml of the antimetabolite, while the left eye was injected with 0.2 ml of saline subconjunctivally, as a control. The eyes were examined histologically, in a masked fashion, by light and by transmission electron microscopy. In each treatment group, two eyes were examined after one week, and three eyes were examined one month after the subconjunctival injection. RESULTS: Electron microscopy revealed toxic effects in the epithelium of the ciliary body of all treatment groups. The 5-fluorouracil group revealed focal mitochondrial edema, enlargement of intercellular spaces, and dilatation of intracellular spaces. The mitomycin C group showed pyknotic nuclei, enlargement of intercellular spaces, and irregular flattened epithelial cells. The severity of changes correlated with concentration and length of exposure. No pathology was found by light microscopy in all groups. CONCLUSIONS: This study demonstrates that subconjunctival antimetabolites mitomycin C and 5-fluorouracil can penetrate the sclera and exert toxic effects on the epithelium of the ciliary body, even in low doses. These changes were only apparent by electron microscopy and were still present one month after the injection. These findings may contribute to the theory that the application of antimetabolites during or after surgery has a direct effect on the epithelium of the ciliary body, besides its known effect on the conjunctiva. Further studies are needed to evaluate its effect on intraocular pressure.

Large soft contact lenses in the management of leaking blebs.

PURPOSE: To investigate the efficacy of a new large permanent wear soft contact lens in the management of leaking blebs following trabeculectomy. METHODS: Twenty-four patients with leakage from a trabeculectomy bleb, both fornix based and limbal based, with and without mitomycin adjuvant, were treated with a 78% water content soft contact lens of 17.5 mm diameter, fit according to each patient's keratometry readings. RESULTS: The leakage from a conjunctival trabeculectomy bleb was successfully treated in 22 out of 24 patients. CONCLUSIONS: The 17.5 mm 78% water content permanent wear soft contact lens is a preferred method of management of leaking blebs when specifically tailored to the patient's corneal curvature.

Nd: YAG laser for Ahmed tube shunt occlusion by the posterior capsule.

The authors describe the case of a 60-year-old aphakic woman who had suffered from glaucoma with uncontrolled intraocular pressure. She was treated by Ahmed tube shunt implantation. On the first postoperative day, the intraocular pressure was unacceptably high and the tip of the implant tube was seen to be embedded in a fold of the posterior capsule, with its opening covered by the posterior capsule. The authors used the Nd:YAG laser to cut open the fold of the posterior capsule that was covering the tip of the tube, thereby restoring the intraocular pressure to normal. To the best of the authors' knowledge, this is the first report of a tube shunt occlusion by the posterior capsule resolved by the Nd:YAG laser.

Intraocular pressure after neodymium:YAG laser treatments in the anterior segment.

Intraocular pressure (IOP) increase soon after neodymium:YAG (Nd:YAG) treatments in the anterior segment has been reported. To evaluate this complication in a large sample of patients, we conducted a retrospective study of all Nd:YAG treatments during three years. Three hundred forty capsulotomies and 212 iridotomies were performed with the Q-switched Nd:YAG laser. An IOP elevation of 10 mm Hg or more within two hours of laser surgery was seen in 15 eyes (4.4%) that had a capsulotomy but in 45 eyes (21.2%) that had an iridotomy. In 13 of the 15 eyes in which the IOP increased after capsulotomy, additional risk factors (glaucoma, high myopia, aphakia) were found. Our results indicate that posterior capsulotomy with the Nd:YAG laser in otherwise healthy, pseudophakic eyes is usually not accompanied by immediate IOP elevation. Elevation can be predicted by risk factors and therefore anticipated in a small group of vulnerable patients.

Persistently raised intraocular pressure following extracapsular cataract extraction.

In this population based study we have reviewed the files of all patients who underwent an extracapsular cataract extraction (ECCE) between 1984 and 1987, were normotensives prior to surgery, and were followed up for at least 10 months after the ECCE. From a total of 1047 operations 746 qualified for the inclusion criteria; of these, 16 (2.1%) were found to have a consistently raised intraocular pressure (greater than 21 mmHg) on more than two occasions) at four months or later after surgery and throughout at least a six-month period. An increased incidence of secondary aphakic glaucoma was associated with anterior chamber IOL implantation (p less than 0.001) and posterior capsule rupture (p less than 0.01), but not with any of the other variables examined (age, sex, surgeon).

One-stage reconstruction of a large upper lid defect in a newborn.

Full-thickness defects of the upper eyelids require immediate reconstruction to ensure protection of the cornea. A technique is described for a one-stage reconstruction of a large congenital defect of upper eyelid in a newborn. The reconstruction was composed of a mucosa-lined transpositional musculocutaneous flap. The advantages of this method over previous methods are discussed.

Increased aqueous lactic dehydrogenase in Coat's disease.

A case of early childhood Coats's disease in a ten-month-old boy is presented. The lactic dehydrogenase aqueous:serum ratio was very high (6:1). A ratio higher than 3:1 in Coats's disease or in any other eye infection has never been reported except in cases of retinoblastoma. Since retinoblastoma does not always show calcification in x-rays, it may be concluded that in certain cases it would be impossible to discriminate between Coats's disease and retinoblastoma (except in pathologic analysis) with any available diagnostic tools.

The correlation between intraocular pressure and refractive status.

A comprehensive glaucoma screening of residents of three urban areas in southern Israel, aged 40 years and above, was performed between 1982 and 1984. Among other factors tested, intraocular pressure (IOP) and refractive status were recorded and the association between them was analyzed. Information on both factors was available in 2,403 (4,821 eyes) of the 2,594 persons participating. There were significantly more myopes among persons with IOPs of more than 20 mm Hg than with lower IOPs. Mean IOP increased gradually from 14.19 mm Hg in hypermetropes to 16.00 mm Hg among high myopes. Furthermore, the association between refractive status and IOP was stronger among Jews of North African or Asian origin than among Jews of European origin.

Long-term outcome of primary acute angle-closure glaucoma.

Factors influencing the long-term cure of 116 consecutive cases of acute angle-closure glaucoma, with at least one year's follow-up were examined. Delay in presentation and the time needed to terminate the attack were found to have a detrimental effect on the final outcome, while the height of the intraocular pressure at the time of the attack was found to be unimportant in predicting the long-term prognosis of the disease.

Papiloedema: benign intracranial hypertension in menarche.

Benign intracranial hypertension has been described in association with hormonal imbalance. We hereby present a rare case of transient, severe swelling of the optic discs during menarche, diagnosed as BIH.

Epidemiology of acute angle-closure glaucoma: incidence and seasonal variations.

126 cases of acute angle-closure glaucoma were encountered in the total population of the Israel Negev region during 12 years. This constitutes an incidence of 4.2/100,000/year in the total population and 11.1/100,000 in the over-30 population. The female:male ratio was 2.1:1 and the most frequently affected age-group was the 51-60 one; when age adjustment was made for the total population, the risk was equally high for all ages above 50. The ethnic origin had no effect on the incidence. A statistically significant preponderance of attacks occurring during summer and winter was found.