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Lens Capsule (lens + capsule)
Selected AbstractsContributions of Mouse Genetic Background and Age on Anterior Lens Capsule ThicknessTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 12 2008Brian P. Danysh Abstract Accurate lens capsule thickness measurements are necessary for studies investigating mechanical characteristics of the capsule. Confocal Z -axis imaging was used to measure the anterior lens capsule thickness of living intact lenses with minimal tissue manipulation. Measurements of the anterior capsule thickness is reported for the first time in young and old mice from four inbred strains, BALB/c, FVB/N, C57BL/6, and 129X1, and the outbred strain ICR. Our data demonstrates that the mouse anterior lens capsule continues to grow postnatally similar to that described in other mammals. It is also shown there is a significant difference in anterior lens capsule thickness between unrelated mouse strains, suggesting that capsule thickness is a quantitative trait shared by strains with common ancestry. Measurements, taken from other regions of FVB/N capsules revealed the anterior pole to be the thickest, followed by the equatorial region and posterior pole. In addition to mouse, anterior capsule measurements taken from intact cattle, rabbit, rat lenses, and human capsulotomy specimens correlated with the overall size of the animal. Anat Rec, 2008. © 2008 Wiley-Liss, Inc. [source] Implantable Imaging System for Visual ProsthesisARTIFICIAL ORGANS, Issue 6 2010Chuanqing Zhou Abstract In order to propose a method of intraocular imaging system for the visual prosthesis, an implantable microcamera was developed and evaluated in vivo. The microcamera was specially developed and shaped to fit the rabbit's lens capsule and encapsulated with the biocompatible silicone. To evaluate the feasibility of this novel approach, the custom-built device was implanted following the surgical extraction of rabbit's lens. And clinical examinations were performed 1 day, 3 days, 1 week, 2 week, and 1 month postoperatively, including slit-lamp examination, intraocular pressure, wound status, anterior chamber depth, the presence of the iris fibrosi of neovascularization, and the position of the implant. Real-time imaging was performed in vivo 1 month after the operation, and the acquired images were processed with the software and hardware that were specially developed for generating the stimulating pulses. Short-term results showed the novel approach is promising. [source] 2267: Safety of the anterior vitreous detachment induced by microplasmin, pharmacologic vitreolysis to separate the posterior capsule from the anterior hyaloidACTA OPHTHALMOLOGICA, Issue 2010J VAN LOOVEREN Purpose The aim of this project is to establish the safety of the use of microplasmin in the vitreolenticular interface to promote the separation of the anterior hyaloid from the posterior capsule. Methods The safety of the use of microplasmin solution will be examined in 24 eyes of 12 rabbits after having performed a cataract surgery and a primary posterior continuous curvilinear capsulorhexis and having exposed the anterior hyaloid interface with a solution of different doses of microplasmin (125µg or 250µg in 0.1ml balanced salt solution)and having left this solution in place during different time intervals starting from 5 minutes to one hour. The rabbit eyes will be examined at well-defined time intervals: day 1 and 7, month 1,2,3,6 and 12. Slitlamp examination and OCT-SLO imaging will be performed to monitor ocular inflammation, visual axis reproliferation and anterior vitreous anatomy. Conclusion Congenital cataracts, whether or not combined with persistent fetal vasculature may present different degrees of congenital dysgenesis of the vitreolenticular interface. Pharmacological separation of the interface between posterior lens capsule and anterior hyaloid would be benificial to improve the surgical outcome. Therefore the feasibility, safety and clinical application of intravitreal injection of microplasmin for this indication need to be examined first. [source] Crystal deposits on the lens capsules in Bietti crystalline corneoretinal dystrophy associated with a mutation in the CYP4V2 geneACTA OPHTHALMOLOGICA, Issue 5 2010Yumiko Yokoi Abstract. Purpose:, We report a patient (Case 1) with Bietti crystalline corneoretinal dystrophy (BCD) associated with previously unknown findings of crystal-like deposits on the anterior and posterior lens capsules. This patient is one of four (Cases 1,4) in whom we have found BCD associated with the same mutation in the CYP4V2 gene. Methods:, We present a case report with molecular diagnosis. A 45-year-old man (Case 1) was referred to our clinic with complaints of gradual progression of visual disturbances and night blindness. His visual acuity was limited to hand movement bilaterally. Slit-lamp biomicroscopy disclosed glistening, crystal-like deposits on the anterior and posterior lens capsules, as well as on the corneal stroma near the corneoscleral limbus. No such deposit was found in the lens stroma. Fundus examination disclosed profound chorioretinal atrophy with scarce crystal deposits. Full-field electroretinography showed extinguished responses of isolated rods, isolated cones, and mixed rods and cones. Results:, Molecular genetic analysis revealed that the subject had a homozygous mutation in the CYP4V2 gene (IVS6,8delTCATACAGGTCATCGCG/insGC), which is most commonly found in Japanese patients with BCD. Three other cases (Cases 2,4) of BCD associated with the same mutation did not show such crystal-like deposits on the lens surface. Conclusions:, Although their exact origin remains unknown, crystal-like deposits may appear on the lens capsule of patients with BCD associated with a mutation in the CYP4V2 gene. [source] Prophylaxis of posttraumatic endophthalmitisACTA OPHTHALMOLOGICA, Issue 2009A ABU EL ASRAR Infectious endophthalmitis is a devastating complication of open globe injuries. The incidence of culture-positive endophthalmitis after open globe injuries varies between 0.5% and 17%. Several reports have demonstrated that delayed primary repair, dirty wound, breach of lens capsule, retained intraocular foreign body (IOFB), grade 4 injury (presenting visual acuity of worse than 5/200 to light perception), placement of primary intraocular lens, and rural setting are associated with an increased risk of posttraumatic endophthalmitis. Posttraumatic endophthalmitis is associated with its own microbiologic spectrum which is distinct from other subgroups of exogenous endophthalmitis. Posttraumatic endophthalmitis still carries a poor prognosis. Reasons for guarded prognosis include polymicrobial infection and the virulence of the infecting microorganisms. In addition, concomitant injuries may directly result in ocular damage that limits ultimate visual recovery. Because of the substantial incidence of endophthalmitis after open globe injuries, careful consideration should be given to the use of prophylactic antimicrobial therapy. The purpose of prophylaxis is to provide effective antibiotic levels as rapidly as possible against a broad range of organisms. Good coverage for most organisms is obtained with intravenous vancomycin coupled with a third generation cephalosporin, such as ceftazidime, which can penetrate the vitreous cavity in effective levels in inflamed aphakic experimental eyes. Recently, the use of prophylactic intravitreal antibiotic administration in high-risk cases was recommended. [source] The distribution of neuroglobin in mouse eyeACTA OPHTHALMOLOGICA, Issue 2009Y YOU Purpose To determine the distribution of neuroglobin (Ngb) in mouse eye. Ngb is predominantly expressed in the nervous system,and at particularly high levels in the retina. Ngb may serve as a reactive oxygen scavenger and may protect the tissue of eye from ischemia/hypoxia injuries. However,the distribution of Ngb in the eye is still controversial. Methods Two polyclonal antibodies against Ngb were used in this immunohistochemical study, both of which were raised in rabbits. One of these two antibodies was generated against the whole recombinant protein of mouse Ngb and the other was generated against amino acid positions 55-70 of mouse and human Ngb. The expression of Ngb was analyzed with light microscopy on tissue sections. Results These two antibodies showed comparable results. Ngb was expressed in the layers of the retina, including the ganglion cell layer, inner and outer nuclear layers, inner and outer plexiform layers, the inner segments of the photoreceptors and the retinal pigment epithelium. Ngb was also detected in other structures of the eye, including the epithelium and endothelium of cornea,the stroma of iris,the ciliary body, the lens epithelium, and the sclera. However, Ngb was not expressed in the corneal stroma, the lens capsule, the lamellar fibers of lens, the pigment epithelium of ciliary body or the pigment layer of iris. Conclusion Ngb was found widely distributed in mouse eye. This finding can be explained by the fact that most of the structures of the eye originated from neural crest/neural ectoderm. Future experiments will focus on the distribution of Ngb at the mRNA level (in situ hybridization),and the quantitative expression levels at baseline and after hypoxic/ischemic challenge. [source] Investigation of particular surgical steps in epiretinal prostheses implantation procedure in pigsACTA OPHTHALMOLOGICA, Issue 2009D IVASTINOVIC Purpose Proliferative vitreoretinopathy (PVR) is known a known complication of implantation of epiretinal prostheses in porcine eyes using our combined surgical procedure of vitrectomy, lensectomy, large scleral incision and retinal tack insertion. The aim of the present experimental study is to investigate the intraocular reaction to particular parts of the epiretinal prostheses implantation procedure in pigs. Methods 15 pigs were divided into 3 groups. Group 1 (n=6) underwent vitrectomy, lensectomy, insertion of inactive epiretinal prosthesis through a scleral incision and fixation to the posterior pole with a retinal tack. In group 2 (n=5) vitrectomy, scleral incision and retinal tack insertion were performed. Group 3 (n=4) received vitrectomy, scleral incision and insertion of a shortened prosthesis into the vitreous cavity. The follow up was 4 weeks. Results PVR was observed in all eyes of group 1 and in one eye of the group 3 with unintentional perforation of the lens capsule by the shortened implant. In all other eyes funduscopy revealed no clinical pathology. Conclusion Our results indicate that lensectomy is the key stimulus for PVR in porcine eyes while other steps of the implantation procedure are well tolerated. Though pigs do not seem to be a reactive animal model, lens manipulation should be avoided in the surgical procedure for the implantation of retinal prostheses. [source] Unraveling the genetics of exfoliation glaucomaACTA OPHTHALMOLOGICA, Issue 2008F JONASSON Purpose To give an account of our recent discovery (2007) of the association of lysyl oxidase like 1 (LOXL1) sequence variants and exfoliation glaucoma (XFG) as well as later replications in other populations. Methods We did a genome-wide association study on open angle glaucoma cases and controls using the Illumina 300 chip. This chip includes probes for 317.000 single , nucleotide polymorphisms (SNPs), that tag, as highly correlated surrogates about 80% of the 2.1 million known common SNPs in the Caucasian genome. For diagnosis of exfoliation syndrome a peripheral band or central shield of exfoliative material on the anterior lens capsule was required. Results When we had done 195 open angle glaucoma cases high genome wide significance was achieved on chromosome 15q24.1 an association later found to be confined to XFG only. This SNP (rs2165241T) was located in the first intron of the LOXL1 gene. We then added 11 correlated SNPs that are not on the Illumina chip and found that two non-synonymous variants in the first exon of LOXL1 can jointly account for all the observed association (R141L, OR 2.5; G153D, OR 20.1). Combined the variants explained 99% of the population attributable risk for exfoliation glaucoma. Conclusion These findings have now largely been confirmed in numerous American, Asian, Australian and European studies, and in all instances do these polymorphisms in the LOXL1 gene confer risk to XFG. LOXL1 is cross linking enzyme responsible for elastin polymer deposition in ocular tissue. The LOXL1 discovery is the first big hit in the search for genetic background for exfoliation glaucoma. These findings may soon influence monitoring of glaucoma suspects in the clinic targeting persons with the high risk haplotypes. [source] Deposition of triamcinolone crystals on the posterior lens capsule following prone posturing post-vitrectomyACTA OPHTHALMOLOGICA, Issue 6 2006Paul A. Cauchi No abstract is available for this article. [source] Excessive maternal caffeine exposure during pregnancy is cataractogenic for neonatal crystalline lenses in rats: a biomicroscopic and histopathologic studyACTA OPHTHALMOLOGICA, Issue 5 2004Cem Evereklioglu Abstract. Purpose:,To investigate histologically the influence of maternal caffeine exposure during pregnancy in vivo on crystalline lenses in neonatal rats. Methods:,Experimentally naive, female Wistar-albino rats (200,220 g) were mated with adult male rats over 2 days for copulation. After confirming pregnancy with a vaginal smear method, 50 gravid rats (dams) were randomly divided into five groups (n = 10 in each), consisting of one control and four experimental groups. Groups 1, 2 and 3 experimental dams were treated with intraperitoneal (i.p.) caffeine at doses of 25, 50 and 100 mg/kg/day, respectively, during pregnancy from gestational day 9 through to day 21. Group 4 dams were treated with caffeine in distilled water in a gavage at a dose of 50 mg/kg/day. Group 5 control dams were given i.p. saline solution daily for the same period. After normal delivery, the eyes were examined by slit-lamp biomicroscopy. The neonates were then killed by decapitation at postnatal days 1 or 30 and the eyes removed for histopathologic investigation of the lenses. Results:,Group 1 and control eyes had normal anterior lens capsules with a single layer of anterior cuboidal epithelial cells, regularly oriented cortical and nuclear lens fibres, and a clear posterior lens capsule with no lining epithelial cells behind the equator. In the remaining groups, histopathologic findings suggesting cataractogenesis included eosinophilic degeneration, lens fibre cell swelling and liquefaction, central lens fibres with retained nuclei, and prominent epithelial cells lining the posterior lens capsule behind the equator. Moreover, some lenses in group 3 had immature cataract on slit-lamp biomicroscopic examination at postnatal day 30. Conclusion:,Excessive maternal caffeine exposure during pregnancy had cataractogenic effects on developing crystalline lenses in newborn rat eyes, both macroscopically and histopathologically. If an appropriate dose of caffeine can be identified, caffeine-induced cataract formation may be used as a new experimental cataract model in animal studies. [source] 2333: Cultivation of limbal stem cells-derived corneal epithelium on different biologic materials for clinical transplantationACTA OPHTHALMOLOGICA, Issue 2010G PETROVSKI Purpose To develop simple, reproducible, animal-materials free method for cultivating limbal stem-cells and differentiating them into corneal epithelium on different human biologic materials for clinical transplantation. Methods The limbal tissues (2x2mm) were harvested from cadavers not more than 8 hours after death and proliferated in vitro on cell culture tissue plates, human amniotic membranes (HAM) or human lens capsules in medium containing human AB serum. Cell viability was tested using the MTT assay and annexin-FITC/Propidium Iodide positivity methods. Molecular gene and immunofluorescent marker studies for stemness, proliferation and differentiation were used for the analysis. Results Over a period of one year, 50 limbal tissue explants were cultivated. Emergence of cells at one edge of the explants occurred within 24 hours from culturing and formed monolayer within 14 days. Although the speed of cell growth varied among donors and types of media for growth, inadequate growth at two weeks was never recorded. The viability of the cells at 7 and 14 days of cultivation was higher than 96% except in case of HAM use where viability was below 80%. The growing cells were characterized for their positivity for stemness (P63, ABCG2), proliferation (ki67) and epithelial cell markers CK 3, 8, 12, 14, 18 and 19. Conclusion We demonstrate a simple, animal-materials free technique for generating corneal epithelium from cadavers or alternatively from autologous donors for viable cell growth on different biologic materials for transplantation. The growth of corneal epithelium on lens capsules proved to be superior compared to the other cultivation techiques. [source] Crystal deposits on the lens capsules in Bietti crystalline corneoretinal dystrophy associated with a mutation in the CYP4V2 geneACTA OPHTHALMOLOGICA, Issue 5 2010Yumiko Yokoi Abstract. Purpose:, We report a patient (Case 1) with Bietti crystalline corneoretinal dystrophy (BCD) associated with previously unknown findings of crystal-like deposits on the anterior and posterior lens capsules. This patient is one of four (Cases 1,4) in whom we have found BCD associated with the same mutation in the CYP4V2 gene. Methods:, We present a case report with molecular diagnosis. A 45-year-old man (Case 1) was referred to our clinic with complaints of gradual progression of visual disturbances and night blindness. His visual acuity was limited to hand movement bilaterally. Slit-lamp biomicroscopy disclosed glistening, crystal-like deposits on the anterior and posterior lens capsules, as well as on the corneal stroma near the corneoscleral limbus. No such deposit was found in the lens stroma. Fundus examination disclosed profound chorioretinal atrophy with scarce crystal deposits. Full-field electroretinography showed extinguished responses of isolated rods, isolated cones, and mixed rods and cones. Results:, Molecular genetic analysis revealed that the subject had a homozygous mutation in the CYP4V2 gene (IVS6,8delTCATACAGGTCATCGCG/insGC), which is most commonly found in Japanese patients with BCD. Three other cases (Cases 2,4) of BCD associated with the same mutation did not show such crystal-like deposits on the lens surface. Conclusions:, Although their exact origin remains unknown, crystal-like deposits may appear on the lens capsule of patients with BCD associated with a mutation in the CYP4V2 gene. [source] Excessive maternal caffeine exposure during pregnancy is cataractogenic for neonatal crystalline lenses in rats: a biomicroscopic and histopathologic studyACTA OPHTHALMOLOGICA, Issue 5 2004Cem Evereklioglu Abstract. Purpose:,To investigate histologically the influence of maternal caffeine exposure during pregnancy in vivo on crystalline lenses in neonatal rats. Methods:,Experimentally naive, female Wistar-albino rats (200,220 g) were mated with adult male rats over 2 days for copulation. After confirming pregnancy with a vaginal smear method, 50 gravid rats (dams) were randomly divided into five groups (n = 10 in each), consisting of one control and four experimental groups. Groups 1, 2 and 3 experimental dams were treated with intraperitoneal (i.p.) caffeine at doses of 25, 50 and 100 mg/kg/day, respectively, during pregnancy from gestational day 9 through to day 21. Group 4 dams were treated with caffeine in distilled water in a gavage at a dose of 50 mg/kg/day. Group 5 control dams were given i.p. saline solution daily for the same period. After normal delivery, the eyes were examined by slit-lamp biomicroscopy. The neonates were then killed by decapitation at postnatal days 1 or 30 and the eyes removed for histopathologic investigation of the lenses. Results:,Group 1 and control eyes had normal anterior lens capsules with a single layer of anterior cuboidal epithelial cells, regularly oriented cortical and nuclear lens fibres, and a clear posterior lens capsule with no lining epithelial cells behind the equator. In the remaining groups, histopathologic findings suggesting cataractogenesis included eosinophilic degeneration, lens fibre cell swelling and liquefaction, central lens fibres with retained nuclei, and prominent epithelial cells lining the posterior lens capsule behind the equator. Moreover, some lenses in group 3 had immature cataract on slit-lamp biomicroscopic examination at postnatal day 30. Conclusion:,Excessive maternal caffeine exposure during pregnancy had cataractogenic effects on developing crystalline lenses in newborn rat eyes, both macroscopically and histopathologically. If an appropriate dose of caffeine can be identified, caffeine-induced cataract formation may be used as a new experimental cataract model in animal studies. [source] | ||||||||||