Lens epithelial changes and mutated gene expression in patients with myotonic dystrophy.
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AIMS: Examination of the expression of the mutated allele of myotonic dystrophy protein kinase gene and lens epithelial cell changes in patients with myotonic dystrophy. METHODS: Six eyes from three patients with myotonic dystrophy underwent cataract surgery. The lens epithelium was photographed to examine the morphological changes. mRNAs were extracted to determine myotonic dystrophy protein kinase gene expression in the lens epithelium and peripheral blood. Age matched lens epithelial cells from senile cataracts were used as controls. RESULTS: All eyes showed iridescent or posterior subcapsular lens opacity. The expression of the myotonic dystrophy protein kinase gene with trinucleotide repeat expansion was evaluated by reverse transcriptase polymerase chain reaction, Southern blotting, and sequence analysis. Lens epithelial cell densities were extremely reduced in the patients compared with the control group. CONCLUSION: To the authors' knowledge, this is the first report to describe the relation between lens epithelial cell changes and mutated gene expression in patients with myotonic dystrophy. The gene may be mitotically unstable in the lens epithelial cells; it may influence cell density and lens epithelial function, and it may lead to the development of typical subcapsular lens opacity. (+info)
Equine phacoclastic uveitis: the clinical manifestations, light microscopic findings, and therapy of 7 cases.
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This retrospective clinical study describes the clinical manifestations, light microscopic findings, and diagnosis and treatment of acute and chronic lens rupture in the horse. Rupture of the lens capsule in the horse usually results in a chronic, blinding inflammation (phacoclastic uveitis) unless prompt surgical and medical therapies are implemented. The clinical manifestations of acute lens capsule rupture included: cataract; intralenticular displacement of iridal pigment; lens cortical fragments attached to the perforated lens capsule, iris, and corneal endothelium; miosis; aqueous flare; and usually a corneal or scleral perforation with ulceration or focal full thickness corneal edema and scarring. The clinical signs of chronic phacoclastic uveitis include blindness, phthisis bulbi, and generalized corneal opacification related to scarring, vascularization, pigmentation, and edema. In one horse, acute phacoclastic uveitis was successfully treated with phacoemulsification to remove the ruptured lens and medical therapy to control the accompanying inflammation. The affected eyes of the horses with chronic phacoclastic uveitis were enucleated because of persistent clinical signs of nonulcerative keratitis and uveitis, despite long-term medical management. The clinical manifestations and lack of improvement with medical therapy are similar in the horse, dog, cat, and rabbit. However, the histologic findings in equine phacoclastic uveitis differ significantly from those in the dog, and rabbit. (+info)
Herpes simplex virus DNA in the lens one year after an episode of retinitis.
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The present report describes a case where HSV was detected by polymerase chain reaction (PCR) in the lens cortical material removed during cataract surgery one year after resolution of retinal inflammation in a patient with ARN. (+info)
Intraoperative complications during cataract surgery in the very old.
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PURPOSE: To determine if there is a difference in intraoperative complications during cataract surgery in very old patients (> or = 88 years) compared with younger patients (< 88 years). METHODS: The records of 802 consecutive cataract operations were reviewed. Identical techniques of small-incision phacoemulsification were used in all cases. A total of 102 eyes were in patients aged 88 to 98, designated as the "very old." The remaining 700 eyes were in patients under 88, designated as "younger." The incidence of intraoperative complications in the 2 groups was compared. RESULTS: Posterior capsule tears, vitreous loss, and loss of the nucleus were found as complications. Overall, these events occurred in 10% of the very old and in only 3% of those under age 88. Vitreous loss occurred in 7% of the very old and in only 1.6% of those under 88. There was 1 dropped nucleus in the very old. In the younger patients, 90.5% of eyes with complicated surgery achieved 20/40 visual acuity or better, but only 40% of complicated cases in the very old achieved this. Furthermore, 50% of complicated cases in the very old had visual acuity of 20/200 or worse, all directly attributed to surgical difficulties. Fifteen percent of patients in both groups had trabeculectomies with no influence on complications. We noted that 8% of the very old required pupil stretching compared with 2% of those under 88. CONCLUSIONS: This study strongly suggests that very old patients (i.e., those 88 years and older) have a higher incidence of intraoperative complications during cataract surgery than younger patients. Furthermore, such complications may result in severe visual loss. These findings may have significance as the population ages. (+info)
Causes of severe visual impairment and blindness in children attending schools for the visually handicapped in the Czech Republic.
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AIMS: To describe the causes of severe visual impairment and blindness in children in schools for the visually handicapped in the Czech Republic in 1998. METHODS: Pupils attending all 10 primary schools for the visually handicapped were examined. A modified WHO/PBL eye examination record for children with blindness and low vision was used. RESULTS: 229 children (146 males and 83 females) aged 6-15 years were included in the study: 47 children had severe visual impairment (20.5%) (visual acuity in their better eye less than 6/60), and 159 were blind (69.5%) (visual acuity in their better eye less than 3/60). Anatomically, the most affected parts of the eye were the retina (124, 54.2%), optic nerve (35, 15.3%), whole globe (25, 10.9%), lens (20, 8.7%), and uvea (12, 5.2%). Aetiologically (timing of insult leading to visual loss), the major cause of visual impairment was retinopathy of prematurity (ROP) (96, 41.9 %), followed by abnormalities of unknown timing of insult (97, 42.4%), and hereditary disease (21, 9.2%). In 90 children (40%), additional disabilities were present: mental disability (36, 16%), physical handicap (16, 7%), and/or a combination of both (19, 8%). It was estimated that 127 children (56%) suffer from visual impairment caused by potentially preventable and/or treatable conditions (for example, ROP, cataract, glaucoma). CONCLUSIONS: Establishing a study group for comprehensive evaluation of causes of visual handicap in children in the Czech Republic, as well as for detailed analysis of present practice of screening for ROP was recommended. (+info)
Fibrous congenital iris membranes with pupillary distortion.
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BACKGROUND: In 1986 Cibis and associates described 2 children with a new type of congenital pupillary-iris-lens membrane with goniodysgenesis that was unilateral, sporadic, and progressive. These membranes were different from the common congenital pupillary strands that extend from 1 portion of the iris collarette to another or from the iris collarette to a focal opacity on the anterior lens surface. They also differed from the stationary congenital hypertrophic pupillary membranes that partially occlude the pupil, originating from multiple sites on the iris collarette, but not attaching directly to the lens. CASE MATERIAL: The present report is an account of 7 additional infants with congenital iris membranes, similar to those reported by Cibis and associates, which caused pupillary distortion and were variably associated with adhesions to the lens, goniodysgenesis, and progressive occlusion or seclusion of the pupil. Six of the 7 patients required surgery to open their pupils for visual purposes or to abort angle closure glaucoma. A remarkable finding was that the lenses in the area of the newly created pupils were clear, allowing an unobstructed view of normal fundi. CONCLUSION: This type of fibrous congenital iris membrane is important to recognize because of its impact on vision and its tendency to progress toward pupillary occlusion. Timely surgical intervention can abort this progressive course and allow vision to be preserved. (+info)
Exogenous Pseudomonas endophthalmitis: a cause of lens enucleation.
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Pseudomonas aeruginosa eye infection, although uncommon, may be a devastating disease if not recognised and treated appropriately, especially in premature infants. The case is presented of a premature baby who lost her right eye from invasive exogenous Ps aeruginosa eye infection. (+info)
Multiple developmental defects derived from impaired recruitment of ASC-2 to nuclear receptors in mice: implication for posterior lenticonus with cataract.
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ASC-2, a recently isolated transcriptional coactivator molecule, stimulates transactivation by multiple transcription factors, including nuclear receptors. We generated a potent dominant negative fragment of ASC-2, encompassing the N-terminal LXXLL motif that binds a broad range of nuclear receptors. This fragment, termed DN1, specifically inhibited endogenous ASC-2 from binding these receptors in vivo, whereas DN1/m, in which the LXXLL motif was mutated to LXXAA to abolish the receptor interactions, was inert. Interestingly, DN1 transgenic mice but not DN1/m transgenic mice exhibited severe microphthalmia and posterior lenticonus with cataract as well as a variety of pathophysiological phenotypes in many other organs. Our results provide a novel insight into the molecular and histopathological mechanism of posterior lenticonus with cataract and attest to the importance of ASC-2 as a pivotal transcriptional coactivator of nuclear receptors in vivo. (+info)