Incidence Of Ocular Abnormalities Research Articles

Evaluation of a Synthetic Bedding Substrate for Mice (Mus musculus).

This study compared a synthetic bedding substrate (SBS), which has the potential to be a particulate-free animal bedding system, with the standard woodchip bedding. The objective was to demonstrate that the SBS is habitable for mice and reduces particulates to levels that would not contaminate the eye or potentially induce ocular (corneal) injury. Newly weaned mice were placed in either standard woodchip bedding or SBS. All mice were monitored regarding overall health (appearance, food and water intake, natural behavior, clinical signs, and provoked behavior) to verify their ability to adjust to the bedding. At 8 to 10 wk of age, the mice underwent slit-lamp evaluation for ocular (corneal) abnormalities. Results showed significant differences in body weight and overall health between bedding groups. The incidence of ocular abnormalities did not differ significantly between groups. We conclude that, without modifications and more testing, SBS is not a favorable bedding for mice, and results were inconclusive regarding its use as a bedding to preclude ocular contamination.

Rebamipide (OPC-12759) in the Treatment of Dry Eye: A Randomized, Double-Masked, Multicenter, Placebo-Controlled Phase II Study

To investigate the dose response for efficacy of 1% and 2% rebamipide ophthalmic suspension compared with placebo in patients with dry eye. A randomized, double-masked, multicenter, placebo-controlled, parallel-group, dose-response phase II study. A total of 308 patients with dry eye. After a 2-week screening period, patients were randomized to receive placebo or 1% rebamipide or 2% rebamipide administered as 1 drop in each eye 4 times daily for 4 weeks. The primary objective end point was change in fluorescein corneal staining (FCS) score from baseline to last observation carried forward (LOCF). Secondary objective end points were lissamine green conjunctival staining (LGCS) score, tear film break-up time (TBUT), and the Schirmer's test. Secondary subjective end points included dry eye-related ocular symptoms (foreign body sensation, dryness, photophobia, eye pain, and blurred vision) score and patients' overall treatment impression score. Rebamipide dose response was observed in FCS, LGCS, and TBUT scores. Both 1% and 2% rebamipide were significantly more effective than the placebo in terms of the change from baseline to LOCF for FCS, LGCS, and TBUT scores. There was no significant difference between the rebamipide and placebo groups from baseline to LOCF in Schirmer's test values, and dose response was not observed. In the predefined dry eye subpopulation with a baseline FCS score of 10 to 15, the mean change from baseline in the 2% rebamipide group was larger than that in the 1% rebamipide group. Change from baseline to LOCF for all 5 dry eye-related ocular symptom scores and patients' overall treatment impression showed significant improvements in the 1% and 2% rebamipide groups compared with the placebo group, except for photophobia in the 1% rebamipide group. No deaths or drug-related serious adverse events occurred in any treatment group. The incidence of ocular abnormalities was similar across the rebamipide and placebo groups. Rebamipide was effective in treating both objective signs and subjective symptoms of dry eye and were well tolerated in this 4-week study. Although 1% and 2% rebamipide were both efficacious, 2% rebamipide may be more effective than 1% rebamipide in some measures. Proprietary or commercial disclosure may be found after the references.

Reduction of ethanol-induced ocular abnormalities in mice through dietary administration of N-acetylcysteine

N-Acetylcysteine (NAC) is a derivative of the amino acid l-cysteine, which, previously, has been shown to protect against ethanol-induced apoptosis during early development. Ongoing research demonstrates that NAC is also proving clinically beneficial in reducing oxidative stress–mediated lung, liver, and kidney damage, with protection likely resulting from a NAC-mediated increase in glutathione levels. In the present study, the hypothesis that coadministration of NAC and ethanol by means of liquid diet on days 7 and 8 of pregnancy in mice would reduce ethanol's teratogenicity was tested. For this work, adult nonpregnant female mice were acclimated to a liquid diet containing ethanol for 16 days, withdrawn from the ethanol, bred, and then returned to the liquid diet containing 4.8% ethanol and/or either 0.5 or 1-mg NAC/mL diet on their seventh and eighth days of pregnancy. At the concentrations used, the mice received NAC dosages of approximately 300 or 600 mg/kg/day and achieved peak blood ethanol concentrations (BEC) that averaged approximately 200 mg/dL. There was no difference in BEC between the ethanol-alone and ethanol plus 600 mg/kg NAC group. After maternal euthanasia, gestational day (GD) 14 fetuses were removed, fixed, weighed, and examined for the presence and severity of ocular abnormalities, a readily assessed endpoint that results from GD 7 and 8 ethanol exposures. Although the lower dosage of NAC (300 mg/kg) resulted in a decrease in the incidence of ocular defects in both the left and right eyes, this reduction was not statistically significant. However, doubling the NAC concentration did yield a significant change; as compared with the group treated with ethanol alone, the incidence of ocular abnormalities was diminished by 22%. These results show the potential of an orally administered compound with proven clinical efficacy to reduce ethanol's teratogenic effects and support the premise that oxidative damage plays an important mechanistic role in fetal alcohol spectrum disorders.

Hipomagnesemia familiar con hipercalciuria y nefrocalcinosis y asociación con alteraciones oculares

Familial hypomagnesemia with hypercalciuria and nephrocalcinosis is an unusual disease that usually leads to end-stage renal failure. There is no specific treatment and, to a variable degree, patients with this disease present ocular abnormalities. The illness is due to a defect in the reabsorption of magnesium and calcium at the thick ascending limb of Henle because of a mutation of the PCLN-1 gene, which encodes a protein, paracellin-1, which intervenes in the reabsorption of both cations. To review outcome and the incidence of ocular abnormalities in our patients and in cases described in Spain and to compare the incidence found with that in groups from other countries. Retrospective study of a group of patients with familial hypomagnesemia with hypercalciuria and nephrocalcinosis diagnosed at a hospital. There were six girls and three boys with clinical symptoms of polyuria, polydipsia, and less frequently, urinary tract infections and lithiasis. All had hypomagnesemia, hypercalciuria and nephrocalcinosis. Five of the patients had renal failure at diagnosis and four underwent transplantation without recurrence. Eight patients had diverse ocular abnormalities. Eighty-one percent of Spanish patients had ocular abnormalities compared with 24 % of those from other countries. There was no evidence of successful medical treatment. Almost half of the patients presented chronic renal failure at diagnosis and most of the patients reached end-stage renal failure in the second or third decade of life. Normal glomerular filtration rate was found only in patients diagnosed at an early age. The most frequent extra-renal association in Spanish patients (81 %) corresponded to ocular abnormalities. Effective treatment consists of kidney transplantation that completely corrects the tubular disorder.

Ocular abnormalities in down syndrome: An analysis of 140 Chinese children

One hundred forty Chinese children with Down syndrome (DS) treated in the Child Assessment Centre of the Duchess of Kent Children's Hospital in Hong Kong between 1985 and 1996 underwent a detailed ophthalmologic evaluation, including test of visual acuity by behavioral testing or retinoscopy, determination of ocular motility, visual field examination, binocular examination for strabismus, determination of near point convergence and pupillary reflex, and/or slit lamp bimicroscopy and ophthalmoscopy to assess ocular health. Only 43 children (31%) had no ocular abnormalities. The overall incidence of ocular abnormalities was 69%, and included refractive error (58%), strabismus (20%), nystagmus (11%), blepharitis/conjunctivitis (7%), lens opacities (4%), and glaucoma (0.7%). No child had Brushfield spots or keratoconus. The incidence of refractive errors increased with increasing age and nearly doubled at school age. As compared with white children with DS, the Chinese children with DS exhibited a higher incidence of refractive error and a similar incidence of lens opacities but a lower incidence of strabismus, nystagmus, blepharitis, Brushfield spots, and keratoconus. Regular visual surveillance, especially of visual acuity, in children with DS as they mature is important in preventing amblyopia.

Ocular findings in premature infants with grade IV intraventricular hemorrhage.

Grade IV intraventricular hemorrhage (IVH) is a severe complication of premature birth. We retrospectively performed serial exams on 13 infants with grade IV IVH and compared their ocular findings to 11 infants matched by gestational age and birth weight without an IVH. All children in the study were initially examined in the neonatal unit within 8 weeks after birth. Subsequent periodic eye exams were performed until 3 to 7 years of age. Of the 13 grade IV IVHs, there was a 92% incidence of ocular abnormalities, compared to a 73% incidence in the premature group without IVH. The children with grade IV hemorrhages had a statistically significant increased incidence of severe eye disease with resultant visual loss (38%) compared to the non-IVH group. Loss of vision was due to optic atrophy and retinopathy of prematurity. Grade IV IVH children are at high risk for severe eye disease and should have early and frequent ophthalmologic exams.

THE EYE AND LEARNING DISABILITIES

The problem of learning disability has become a matter of increasing public concern, which has led to exploitation by some practitioners of the normal concern of parents for the welfare of their children. A child's inability to read with understanding as a result of defects in processing visual symbols, a condition which has been called dyslexia, is a major obstacle to school learning and has far-reaching social and economic implications. The significance and magnitude of the problem have generated a proliferation of diagnostic and remedial procedures, many of which imply a relationship between visual function and learning.1 The eye and visual training in the treatment of dyslexia and associated learning disabilities have recently been reviewed with the following conclusions by the American Academy of Pediatrics, the American Academy of Ophthalmology and Otolaryngology, and the American Association of Ophthalmology: 1. Learning disability and dyslexia, as well as other forms of school underachievement, require a multi-disciplinary approach from medicine, education, and psychology in diagnosis and treatment. Eye care should never be instituted in isolation when a patient has a reading problem. Children with learning disabilities have the same incidence of ocular abnormalities, e.g., refractive errors and muscle imbalance, as children who are normal achievers and reading at grade level.2-4 These abnormalities should be corrected. 2. Since clues in word recognition are transmitted through the eyes to the brain, it has become common practice to attribute reading difficulties to subtle ocular abnormalities presumed to cause faulty visual perception. Studies have shown that there is no peripheral eye defect which produces dyslexia and associated learning disabilities.5,6