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At least 19 recordsLinked to original sources

Diagnosis and treatment of lens diseases.

The lens represents a unique tissue in light of its embryologic development, retention of old cells and nuclear make-up, transparent nature, immune privileged status, and metabolic restrictions. Disorders of malformation and malposition occur, but cataract development is the most common and significant problem for owners and animals. Technologic and pharmacologic advances have allowed surgical removal of equine cataracts to become an acceptable alternative, capable of returning a visually impaired horse to a functional status. Uveal inflammation represents the greatest threat to successful surgical cataract removal. Veterinarians should consult with those versed in ophthalmology for assistance in diagnosis, prognosis, peroperative treatment, surgical intervention, and follow-up on lens disorders.

Animals↗

The epidemiology of contact lens related diseases in the United Kingdom.

This review evaluates the epidemiologic methods used to study contact lens related diseases in the United Kingdom. The results of these studies are compared to major US studies. The advantages and limitations of various epidemiologic study designs are discussed. The role of noncomparative cohort studies, particularly premarket studies, in underestimating lens related disease is examined. Descriptive studies and the difficulties related to their interpretation are also described. The use of case control studies for investigating both the risks and causes of lens related diseases is evaluated and compared to the cohort study design. The results of these studies in the investigation of the complications of contact lens wear, including keratitis, are summarized. Finally, the relevance of these findings to contact lens wearers and practitioners is explored.

Acanthamoeba Keratitis↗

Cytokine and lipid inflammatory mediator profile of human tears during contact lens associated inflammatory diseases.

Contact lens induced acute red eye (CLARE) and contact lens induced peripheral ulcer (CLPU) are among the most common contact lens induced inflammatory reactions. Both CLARE and CLPU are characterized by corneal infiltration which indicates the presence of chemoattractants and other inflammatory mediators. The aim of this study was to characterize the cytokine and chemotactic lipid inflammatory mediator profile in the tears of people experiencing CLARE or CLPU. Cytokines IL-1 beta, IL-6, IL-8, GM-CSF and LTB4 in tears were measured by antibody sandwich and competition inhibition enzyme-linked immunosorbent assays (ELISA). Platelet activating factor-like activity was measured by a degranulation assay by measuring the release of labelled serotonin from platelets. The functional role GM-CSF and chemoattractants were determined by flow cytometry and chemotaxis. Increased levels of cytokines and chemoattractants were detected in both CLARE and CLPU tears. CLPU tears showed increased levels of LTB4 (P = 0.002) and PAF-like activity (P = 0.047) whereas CLARE tears showed increased levels of GM-CSF (P = 0.002). IL-8 (P < 0.05). LTB4 (P = 0.002) and PAF-like activity (P = 0.047) compared to control tears. Flow cytometric analysis revealed that incubation of PMN with CLARE tears increased the number of IgA receptors indicating that the GM-CSF in CLARE tears was active. Combinations of suboptimal concentrations (which were found in CLARE and CLPU tears) of IL-8 with either LTB4 or PAF significantly (P < 0.0001) enhanced the chemotactic activity for PMN compared to their individual effects. Our data highlight the possible pathophysiological roles of these inflammatory mediators in leukocyte recruitment and activation during ocular inflammatory responses. The results suggests that GM-CSF, IL-8 and LTB4 are active during corneal pathology and LTB4 or IL-8 may maintain the contact lens induced PMN response in vivo.

Acute Disease↗

Lens opacity in patients with hypercholesterolemia and ischaemic heart disease. Electronic lens opacity measurements.

Lens opacity studies were performed using an electronic Lens Opacity Meter (Interzeag Opacity Lensmeter 701) in a population (n = 321) with ischaemic heart disease. These patients are participating in a trial targetting at the reduction of mortality and incidence of myocardial infarction using a cholesterol-lowering drug, simvastatin. A separate study to evaluate the reliability of the method showed good reproducibility. Repeated measurements after a short time-interval (2-10 days) gave statistically lower opacity values either due to a change in lens transparency or perhaps a change in pigment and cell dispersion in the aqueous caused by repeated mydriasis. Lens opacity values showed a highly significant positive correlation to age. Serum cholesterol, systolic blood pressure and smoking habits showed no significant correlations to the levels of lens opacity when adjustments for age were made.

Adult↗

[Hereditary diseases with lens dislocation: clinical aspects].

Ectopia lentis is a common denominator of some connective tissue diseases such as Weill-Marchesani, Ehlers-Danlos, and Marfan's syndromes, osteogenesis imperfecta and homocystinuria. Early differential diagnosis (e.g., Marfan's syndrome vs. homocystinuria) is mandatory for prognostic (aortic aneurysm in Marfan's syndrome), therapeutic (dietetic and vitamin therapy in homocystinuria), and genetic reasons (genetic counseling).

Dwarfism↗

[The application of digital photography with retroillumination for lens in cataract study].

OBJECTIVE: To evaluate the reliability of digital photography with retroillumination for lens as a tool to assess the degree of lens opacity, and to study the morphological features of some lens diseases using the digital images. METHODS: The cataract screener (Neitz CT-S) was connected to a computer capable of acquiring digital images of lens. The digital lens retroillumination and slit lamp images were collected in 64 eyes. Three independent separate examiners took three sets of different CT-S digital photographs in four cataract subjects. The area of lens opacification in the images was measured and analyzed using threshold adjustment in PhotoShop software and a customized program in Matlab software. RESULTS: The distinct digital images of lens cortical opacity, posterior subcapsular opacity and other lens diseases were obtained with CT-S computer digital photography, which images were much better than slit lamp sectional digital images. The sensitivity and specificity of measuring lens opacification with CT-S digital images were 90% and 94% respectively. However, the digital lens retroillumination images were not as sensitive as the slit lamp images for nuclear cataracts. The variation coefficients of lens opacity area in the three sets of CT-S digital images in the same subject, which were taken by the independent examiners, were from 2.23% to 10.86%. The cortical opacification in CT-S digital images was linear, cuniform or clustered aggregate shadow configuration. The posterior subcapsular opacification was discal vacuolar or granular appearance. CONCLUSIONS: The reproducibility of the CT-S digital images taken by the independent examiners is excellent. This technique can objectively show cortical or posterior subcapsular opacities, but nuclear cataracts.

Adult↗

Ocular chrysiasis correlated with gold concentrations in the crystalline lens during chrysotherapy.

The eyes of 11 patients with rheumatoid arthritis (RA) who received extended chrysotherapy (mean cumulative dose greater than 7 grams during a mean 6-year period) were examined biomicroscopically. Minute reddish-purple particles were seen in the cornea (corneal chrysiasis) in 5 and in the lens (lens chrysiasis) in 4 patients. Particulate deposits were absent in 11 other RA patients who had not received gold treatment. Seven crystalline lenses from 5 gold-treated patients were removed surgically because of incidental cataract formation and analyzed for gold content using neutron activation analysis. Although the mean lens gold concentration was higher in these patients than in non-gold-treated controls without RA (0.0073 microgram/grams versus 0.001 microgram/grams), the absolute gold level was markedly lower than that found in 25 diverse tissue analyzed previously. This finding is compatible with the absence of clinical gold-related lens disease or visual impairment.

Adult↗

The influence of the size of the lens in ocular disease.

The mechanism of normal lens growth is considered. This involves both the surface accretion of new fibres and the central compaction of aging fibres. When lens growth is abnormal, it is shown to be retarded in most conditions, but accelerated in diabetes. The relationship between lens growth and ocular disease, in particular angle-closure glaucoma, is discussed.

Aging↗

Inherited metabolic diseases affecting the carrier.

The objective of this review is to draw attention to those inherited metabolic traits which are potentially harmful also for the carrier, and to outline preventive measures, at least for obligate heterozygotes, i.e. parents of homozygous children. Concerning carriers of food-dependent abnormalities, early vascular disease in homocystinuria, hyperammonaemic episodes in ornithine transcarbamylase deficiency, presenile cataracts in galactosaemia as well as galactokinase deficiency, spastic paraparesis in X-linked adrenoleukodystrophy, and HELLP syndrome in mothers of babies with long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency have to be mentioned. In the group of food-independent disorders, clinical features in carriers may be paraesthesias and corneal dystrophy in Fabry disease, lens clouding in Lowe syndrome, lung and/or liver diseases in alpha 1-antitrypsin deficiency, and renal stones in cystinuria type II and III. Finally, two monogenic carrier states are known which in pregnant individuals could possibly afflict the developing fetus, i.e. heterozygosity for galactosaemia and for phenylketonuria. Elevated levels of galactose-1-phosphate have been found in red blood cells of infants heterozygous for galactosaemia born to heterozygous mothers. Aspartame in very high doses is reported to increase blood phenylalanine levels in heterozygotes for phenylketonuria, thus being a risk for the fetus of a heterozygous mother. For some of these carrier states preventive measures can be recommended, e.g. restriction of lactose in parents and heterozygous grandparents of children with galactosaemia and galactokinase deficiency as well as transiently in infants heterozygous for galactosaemia, dietary supplementation with monounsaturated fatty acids in symptomatic carriers for X-linked adrenoleukodystrophy, avoidance of smoking and alcohol in heterozygotes for alpha 1-antitrypsin deficiency, avoidance of episodes of dehydration in heterozygotes for cystinuria, and restriction of aspartame in pregnant women.

Diet↗