Objectives: To compare the recently used phacoemulsification systems using a health technology assessment (HTA) model.

Methods: A self-administered questionnaire, which included questions to gauge on the opinions of the recently used phacoemulsification systems, was distributed to the chief cataract surgeons in the departments of ophthalmology of eighteen tertiary hospitals in Shanghai, China. A series of senile cataract patients undergoing phacoemulsification surgery were enrolled in the study. The surgical results and the average costs related to their surgeries were all recorded and compared for the recently used phacoemulsification systems.

Results: The four phacoemulsification systems currently used in Shanghai are the Infiniti Vision, Centurion Vision, WhiteStar Signature, and Stellaris Vision Enhancement systems. All of the doctors confirmed that the systems they used would help cataract patients recover vision. A total of 150 cataract patients who underwent phacoemulsification surgery were enrolled in the present study. A significant difference was found among the four groups in cumulative dissipated energy, with the lowest value found in the Centurion group. No serious complications were observed and a positive trend in visual acuity was found in all four groups after cataract surgery. The highest total cost of surgery was associated with procedures conducted using the Centurion Vision system, and significant differences between systems were mainly because of the cost of the consumables used in the different surgeries.

Conclusions: This HTA comparison of four recently used phacoemulsification systems found that each of system offers a satisfactory vision recovery outcome, but differs in surgical efficacy and costs.

Disorders of eye development such as microphthalmia and anophthalmia (small and absent eyes respectively), anterior segment dysgenesis where there may be pupillary and iris anomalies, and associated cataract and glaucoma, often lead to visual impairment or blindness. Currently treatment options are limited, as much is unknown about the molecular pathways that control normal eye development and induce the aberrant processes that lead to ocular defects. Mutation detection rates in most of the known genes are generally low, emphasizing the genetic heterogeneity of developmental ocular defects. Identification of the disease genes in these conditions improves the clinical information available for affected individuals and families, and provides new insights into the underlying biological processes for facilitation of better treatment options. Investigation of chromosomal rearrangements associated with an ocular phenotype has been especially powerful for disease gene identification. Molecular characterization of such rearrangements, which pinpoints the region by physically disrupting the causative gene or its regulatory sequences, allows for rapid elucidation of underlying genetic factors that contribute to the phenotype. Genes including PAX6, PITX2, FOXC1, MAF, TMEM114, SOX2, OTX2 and BMP4 have been identified in this way to be associated with developmental eye disorders. More recently, new methods in chromosomal analysis such as comparative genomic hybridization (CGH) microarray, have also enhanced our ability in disease gene identification.

While many experimental studies have shown a protective effect of vitamin C in age-related cataract, other studies have revealed contrasting roles for this nutrient. Oxidative damage in the lens can be prevented by vitamin C. However, a pro-oxidant effect of vitamin C through H2O2 generation has been suggested. Vitamin C has also been shown to play a role in protein glycation, which is observed in cataract formation. A protective effect of dietary energy restriction appears to be inversely related to plasma vitamin C levels in rodents. Moreover, conclusions from human epidemiological and intervention studies are not uniform. The available evidence suggests that maintenance of sufficient plasma vitamin C is needed to prevent oxidative damage in the lens. More research will be needed in order to confirm the relative importance of the different roles of vitamin C in the eye lens.

Stratospheric ozone depletion threatens to increase exposure to ultraviolet (UV) radiation which is known to be a factor in a number of diseases. There is little doubt that cumulative exposure to UV radiation is important in the aetiology of non-melanoma skin cancers. Evidence is also strong for a link with cutaneous malignant melanoma, although here it appears to be intermittent intense exposure that is most damaging. More controversial is the view that exposure to solar radiation is a significant factor in ocular damage, particularly in the formation of cataracts. Earlier studies pointing to such an effect have been criticized and alternative aetiological hypotheses have been proposed. However, other studies do show an effect of UV exposure on cortical cataract. Concern is also growing that UV may be capable of activating viruses and have immunological effects that might exacerbate infectious disease. Very worrying is the possibility that UV exposure can activate the human immunodeficiency virus which might accelerate the onset of AIDS. Any such health effects that have been observed in human populations are the result of exposure to existing, naturally occurring levels of UV radiation. There is, therefore, great concern about the possible exacerbation of these impacts as a result of increased exposure to UV radiation associated with stratospheric ozone depletion. However, any assessment of the nature and scale of such impacts on human health has to deal with several major problems and these are the focus of this paper. There are uncertainties about recent trends in stratospheric ozone and problems in the prediction of future changes. Following on from this are the difficulties of estimating what effects these changes will have on UV flux at ground level in populated areas. Further problems arise in the prediction of changes in biologically significant doses to humans which might be affected by changes in behaviour as well as by changes in the environment. Finally, the limitations of existing epidemiological knowledge of the effects of UV exposure are a constraint on our ability to predict what the health effects of any changed UV doses might be.

The aim of the present study was to investigate the cataract preventive effect of dietary histidine regimes in adult Atlantic salmon (Salmo salar L.) in seawater, both through manipulating the dietary histidine level and feeding period. Mean body weight of individually tagged Atlantic salmon at the start of the experiment was 1662 (sd 333) g. Low prevalence of mild cataracts were recorded in the beginning of June. Three fishmeal and fish oil-based extruded diets (crude protein: 375 g/kg and fat: 342 g/kg), differing only in histidine content (low (L): 9·3, medium (M): 12·8 and high (H): 17·2 g histidine/kg diets), were fed to duplicate net pens in seawater. The experimental period was divided into three seasons (June–July; July–September; September–October), each starting and ending with individual cataract examination, assessment of somatic data, and sampling of lens and muscle tissues for analysis of histidine and histidine derivatives. In July and September, a part of the population fed L- and H-histidine feeds were transferred (crossed over) to respective series of replicate net pens fed L-, M- and H-histidine diets (i.e. eleven experimental feeding groups at trial conclusion). The fish doubled their body weight from June to October, with no systematic effects on weight gain of dietary histidine feeding regimes. Development of severe cataracts was observed between July and September. The cataract severity was directly related to the dietary histidine level fed during the first and second periods. Feeding histidine-supplemented diets (M or H) in the first period from June to July mitigated later cataract outbreaks. The status of selected free imidazoles in muscle and lens tissues reflected the dietary histidine feeding regimes, relative to both feed concentration and feeding duration. The study shows the risk for cataract development for adult Atlantic salmon, 1 year after the transfer of salmon smolts from freshwater to seawater, which to a major extent can be prevented by histidine supplementation just before and during the early phase of cataract development.

La cataracte radio-induite était considérée jusqu’à nos jours comme une pathologie assez peu fréquente, nécessitant de fortes doses de rayonnement (dépassant un seuil élevé, de l’ordre de 2 Grays au cristallin) et se réduisant principalement aux cataractes radiques des patients de radiothérapie. Plusieurs études récentes portant sur des populations aussi diverses que les astronautes, les survivants d’Hiroshima–Nagasaki, les patients ayant subi un scanner céphalique, les « liquidateurs » de Tchernobyl ainsi que quelques expérimentations animales nous amènent à reconsidérer la question : le seuil d’apparition aussi bien des opacités détectables que des cataractes symptomatiques paraît nettement plus bas qu’actuellement estimé. L’existence même d’un seuil n’est plus tout à fait une certitude dans la mesure où la pathogénie de la cataracte radio-induite serait moins de type déterministe (dommage tissulaire direct tuant ou endommageant gravement une population cellulaire donnée) comme on le pensait, mais d’avantage de type stochastique (altération du génome des cellules cibles, perturbation de la division cellulaire, trouble de la différenciation cellulaire des cellules filles). De manière plus pratique, ces observations sont de nature à nous faire reconsidérer la protection des populations spécifiquement exposées : patients et travailleurs principalement. S’agissant des travailleurs, et si ces nouvelles données étaient confirmées, la limite actuelle de dose équivalente au cristallin du code du travail de 150 mSv sur 12 mois consécutifs pourrait, à terme, être revue à la baisse.

The Jackson Laboratory, having the world's largest collection of mouse mutant stocks and genetically diverse inbred strains, is an ideal place to discover genetically determined eye variations and disorders. In this paper, we list and describe mouse models for ocular research available from Mouse Eye Mutant Resource at The Jackson Laboratory. While screening mouse strains and stocks at The Jackson Laboratory (TJL) for genetic mouse models of human ocular disorders, we have identified numerous spontaneous or naturally occurring mutants. We characterized these mutants using serial indirect ophthalmoscopy, fundus photography, electroretinography (ERG) and histology, and performed genetic analysis including linkage studies and gene identification. Utilizing ophthalmoscopy, electroretinography, and histology, to date we have discovered 109 new disorders affecting all aspects of the eye including the lid, cornea, iris, lens, and retina, resulting in corneal disorders, glaucoma, cataracts, and retinal degenerations. The number of known serious or disabling eye diseases in humans is large and affects millions of people each year. Yet research on these diseases frequently is limited by the obvious restrictions on studying pathophysiologic processes in the human eye. Likewise, many human ocular diseases are genetic in origin, but appropriate families often are not readily available for genetic studies. Mouse models of inherited ocular disease provide powerful tools for rapid genetic analysis, characterization, and gene identification. Because of the great similarity among mammalian genomes, these findings in mice have direct relevance to the homologous human conditions.

The optical density of the human crystalline lens progressively increases with age, the greatest increase in the visible spectrum being at short wavelengths. This produces a gradual shift in the spectral distribution of the light reaching the retina, yet color appearance remains relatively stable across the life span, implying that the visual system adapts to compensate for changes in spectral sensitivity. We explored properties of this adaptive renormalization by measuring changes in color appearance following cataract surgery. When the lens is removed, cataract patients often report a large perceptual shift in color appearance that can last for months. This change in color appearance was quantified for four cataract patients (63–84 years) by determining the chromaticity of stimuli that appeared achromatic before surgery, and at various intervals after surgery for up to 1 year. Stimuli were presented on a calibrated CRT as 9.5-deg spots, with 3-s duration and 3-s interstimulus intervals (ISIs). Chromaticity was adjusted by the subjects in CIE L*a*b* color space with luminance fixed at 32 cd/m2, on a dark background. We also estimated the optical density of the cataractous lens by comparing absolute scotopic thresholds from 410 nm to 600 nm before and after surgery. The results demonstrated that immediately following surgery there is a large increase in the short-wave light reaching the retina, mainly below 500 nm. The achromatic settings generally showed an initial large shift in the “yellow” direction after surgery that gradually (but never fully) returned to the original achromatic point before surgery. The shifts in the achromatic point occur over a number of months and appear to occur independently of the fellow eye.

Background: Delirium is frequently observed in clinical practice, particularly in medical and surgical wards and more so among patients at risk, especially elderly with pre-existing central nervous system impairments. Objective: Despite the severe consequences of delirium, epidemiological data relating to incidence of delirium following “minor” surgery are lacking. The aim of the present study was to evaluate the incidence of delirium following cataract surgery in community-dwelling patients. Outcome: For purposes of the present study, the Confusion Rating Scale was used. Results: Of 296 patients fulfilling the inclusion criteria, 13 (4.4%) had had immediate postoperative delirium. The two variables that significantly differentiated between delirious and nondelirious patients were older age (82.1 vs. 73.06 years; p < .001) and more frequent use of benzodiazepine premedication (69% vs. 39.9%; p < .002). Conclusion: These findings suggest that the incidence of delirium following cataract surgery requires greater awareness, possibly changes in premedication, and a longer observation period in the very old.

Objectives: An index approach for measuring the reduction in daily activities of patients suffering from an eye disease associated with progressive visual loss is proposed. The approach is illustrated using data collected from patients with cataract.

Method: The approach uses recently developed methods based on index theory together with measurements of daily activities. In a simulation based on observations of visual acuity and daily activities in patients with cataract, indexes of changes in benefits were estimated for varying levels of visual acuity.

Results: Results show the development of loss in benefits resulting from a progressive deterioration in visual acuity. The results indicate a 40% loss in benefits at low levels of visual acuity, equivalent to a potential increase in benefits of 75% for these individuals following successful treatment.

Conclusions: The proposed index approach may prove useful for measuring reductions in daily activities resulting from the progressive loss of vision in eye disease. The approach has successfully measured the reduction in daily activities in patients with cataract and may be applicable in patients with other eye diseases, including age-related macular degeneration and open-angle glaucoma.

Cataract is a multifactorial disease. Osmotic stress, together with weakened antioxidant defence mechanisms, is attributed to the changes observed in human diabetic cataract. Epidemiological studies provide evidence that nutritional antioxidants slow down the progression of cataract. The usefulness of lycopene, a dietary carotenoid, in the pathogenesis of human cataracts has not been studied so far. Since the epithelium is the metabolic unit of the lens, the effect of lycopene on galactose-induced morphological changes and antioxidant status of human lens epithelial cells (HLEC) in culture was evaluated in the present study. HLEC of fresh cadaver eyes obtained from an eye bank were cultured in medium supplemented with fetal calf serum (200 ml/l). On confluency, the cells were subcultured in medium containing either 30 m-d-galactose or 30 mM-d-galactose + lycopene (5, 10 or 20 μM) for 72 h. The cells were observed under the phase-contrast microscope and transmssion electron microscope for any morphological changes and then harvested for the estimation of various biochemical variables. Malondialdeyde, glutathione and antioxidant enzymes were significantly altered in the control as compared with the normal cultures. Vacuolization was also observed in the presence of galactose. Addition of lycopene confers significant protection against these changes in HLEC.

The effects of acarbose on cataract development, lens aldose reductase (EC 1·1·1·21) activity and lenticular reduced-glutathione content in diabetic sand rats (Psammomys obesus) were determined. Diabetic sand rats (diet-induced) were fed on diets with or without acarbose(0.4 g/kg) for 39 d. Daily plasma glucose, cataract incidence, aldose reductase and glutathione content were evaluated. After 19 d on acarbose, daily plasma glucose profile was significantly reduced compared with that of sand rats not receiving acarbose. Cataract incidence was markedly lower in sand rats treated with acarbose. After 20 d, cataracts had developed in 90% of the animals fed without acarbose, whereas none was observed in sand rats fed with acarbose. After 37 d acarbose treatment the incidence of cataracts reached only 30%. Compared with untreated animals, lens aldose reductase activity was significantly lower in sand rats fed with acarbose for 39 d (7 6 (SE 0·78) v. 3·5 (SE 0·55) μmol NADPH/mg protein per min respectively, P < 0·001). Concomitantly, significantly higher lenticular protein and reduced-glutathione contents (90 (SE 23) v. 240 (SE 23.5) μg/mg tissue respectively, P < 0·001 and 369 (SE 48·6) v. 645 (SE 71·1)μg/mg tissue respectively, P < 0·001) were found. These results suggest that decreasing hyperglycaemia, accompanied by lower aldose reductase activity obtained by acarbose, led to a significant preventive effect on cataract development in sand rats.