ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00076.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00077.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTThe discovery that myopia can be induced in animals has resulted in renewed interest in the condition and it is hoped that information gained about the production, manipulation and prevention of myopia in animals might provide information about naturally occurring myopia in humans. Early experimental work was carried out using monkeys as subjects, but the high cost involved, and the difficulty of obtaining monkeys in adequate numbers for good experimental design and control, made researchers look for more suitable experimental animals. Myopia has also been induced in other animals species such as the domestic cat, the tree shrew, the marmoset, the guinea pig and, most successfully, the domestic chicken. The parallels between experimentally induced myopia, which can only be induced in infant animals, and human myopia which typically develops well after infancy, have still to be established.

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00078.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTOcular axial length and thickness were measured in 12 children (age 4 to 418 days, median 103 days) with unilateral congenital cataract who were referred to St. Erik's Eye Hospital during 1991–1994. The measurements were performed in both eyes with A‐scan ultrasonography before cataract extraction. In 4 children measurement of the axial length was repeated 1 to 4 months after the unilateral cataract extraction. All eyes with congenital cataract were shorter than the normal fellow eye. The individual axial length differences showed a mean value ± SEM of 1.03 ± 0.16 mm. This difference was statistically significant (p<0.01). In the 4 children where measurement of the axial length was repeated, the difference between the eyes after unilateral cataract extraction had become greater than before. In addition, the thickness of the cataractous lens was 0.63 ± 0.17 mm (mean ± SEM) less than the non‐operated clear lens. This difference was statistically significant (p<0.01). In conclusion, in children with unilateral congenital cataract the affected eye has a shorter axial length and a thi

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00079.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTThe effect of 193 nm excimer laser radiation on human corneal endothelial cell density was examined. Fifty‐five eyes from 35 patients underwent photorefractive keratectomy for myopia. Photomicrographs of the endothelium were taken a short time before the operation and on an average of 7 months postoperatively with a specular microscope. The average endothelial cell densities were preoperatively 3375 ± 266 cells/mm2(mean ± SD) and postoperatively 3348 ± 287 cells/mm2, corresponding to a fall of 27 cells/mm2(N = 55). This fall in endothelial cell density was not statistically significant. A significant correlation between the change in cell density and age of the patient was found, with older patients losing more cells (N = 35, 2p<0.05). The magnification of the specular microscope was found to change with corneal thickness. The importance of correcting the endothelial cell densities for corneal thickness is discu

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00080.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTEpithelial hyperplasia has been found to occur after photorefractive keratectomy in eyes treated with small (5 mm or less) ablation zone diameters with the Summit laser, but not with large zones (6 mm) with the VISX laser (Gauthier et al. 1995a). The aim of this study was to further investigate the effect of surgical parameters on epithelial hyperplasia by comparing eyes treated with the same zone diameter but two different lasers. We examined 11 subjects who had photorefractive keratectomy for myopia performed with 5 mm ablation zones with the Summit excimer laser in one eye and the VISX 20/20 laser in the fellow eye an average of 21 months previously. Epithelial thickness and corneal topography were measured. The mean epithelial thickness was not statistically different (p = 0.083) between the eyes treated with the Summit (66 ± 12 μm) and VISX (60 ± 14 μm) lasers. Postoperative corneal dioptric power showed a similar profile between the two eyes at the edge of the zone, with the VISX‐treated corneas being more shallow centrally. There was a trend towards greater epithelial thickness with deeper ablations. This study supports the hypothesis that epithelial hyperplasia is dependent on ablation zone diameter and ablation

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00081.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTCorneal epithelial healing velocity was determined in patients admitted to excimer laser photo refractive keratectomy, by daily video planimetry of the denuded area until complete healing. The epithelial healing process was followed in fellow eyes with regard to intervals between surgery of the two eyes of 1 to 10 weeks. In cases where the fellow eye was treated at one week after the first eye, the lesions healed significantly faster in the second eye as compared to patients with longer delay between the two operations.

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00082.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTSamples of five different solutions for disinfection of soft contact lenses were experimentally inoculated with a strain of Pseudomonas aeruginosa or Serratia marcescens. No bacteria could be detected after one hour in solutions with biguanids, while they survived in reduced number up to 72 h in solutions with polyquaternium as active substance. However, prolonged survival after one week could not be detected. Lenses treated with polyquaternium based contact lens disinfectant solutions overnight may still harbour bacteria, which might increase the risk for bacterial complications, such as keratitis.

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00083.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTThe clinical performance of a portable ultrasound pachometer was compared with a digital, ‘optical’ pachometer attachment of a contact specular microscope. The two separate methods were used to assess central corneal thickness (CCT) in 214 extended‐wear soft contact lens subjects over a cumulative 33 month period. The two test methods did not correlate well (r = 0.56). Mean ultrasound CCT was 0.542 mm ± 0.004 SEM; mean CSM ‘optical’ attachment CCT was 0.562 mm ± 0.004 SEM (significantly different by t‐test; p<0.05). A two‐way anova (each CCT method by immediate duration of extended lens wear, and by duration in study) revealed an apparent underestimation of central corneal thickness by the ultrasound pachometer. While this presumed ultrasound bias or error can be explained by concurrent morphological and physiological changes associated with long‐term contact lens wear, other methodological errors could have influenced the results. Pending additional study, physiologically stressed corneas might be better evaluated by some method of corneal thickness measurement othe

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00084.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

ABSTRACTWe designed and evaluated a new drug delivery system (DDS) in which a drug plate containing levofloxacin was placed between a hydrophilic soft contact lens (SCL) and a non‐hydrophilic SCL. The drug plate (diameter 8.0 mm, thickness 0.2 mm) was prepared by coating and freeze‐drying a poly(vinyl alcohol) (PVA) disc containing 20, 30 or 40 wt% levofloxacin with a block styrene‐(ethylene/butene)‐styrene (SEBS) polymer solution. The release rate of the levofloxacin in vitro reduced with an increase in the concentration of SEBS polymer in solution used for coating. The release rate was well controlled and in zero‐order kinetics was observed. The drug release from the drug plate consisting of a PVA disc loaded with 30 wt% levofloxacin and coated with 7.5 wt% SEBS polymer solution was 3.07 ± 0.39 mg during 8 h. This drug plate was placed on an albino rabbit's eye wearing a hydrophilic soft contact lens (SCL), and then covered with a non‐hydrophilic SCL. The drug concentrations in the anterior chamber were 156.0 ± 133.6 μg/ml and 193.2 ± 136.1 μg/ml after 4 and 8 h, respectively. The values obtained with frequent instillation of 0.5% levofloxacin every 30 min were 9.9 ± 4.3 μg/ml and 12.5 ± 10.0 μg/ml after 4 and 8 h, respectively. Therefore a significantly higher drug level was achieved with DDS compared to f

ISSN:1395-3907    

DOI:10.1111/j.1600-0420.1996.tb00085.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY