Background: Striae and folds are observed with a slitlamp biomicroscope in the cornea following overnight contact lens wear. These phenomena are poorly understood. The aim of this study is to employ confocal microscopy to observe and document these and other morphological changes in the human cornea following overnight contact lens wear.
Methods: Slitlamp biomicroscopy, slit-scanning confocal microscopy and ultrasonic pachometry were performed on both eyes of 13 subjects (3M, 10F, age 24 +/- 3 years) before and after eight hours overnight wear of a -3.00 D Bausch & Lomb one day disposable soft contact lens (Dk/t = 15.1 x 10(-9) [cm/sec] x [ml O2/ml x mmHg]) in one eye; the other non-lens-wearing eye acted as a control.
Results: Following sleep, both corneas were swollen (lens-wearing eye 11.8 +/- 3.8 per cent; control eye 2.1 +/- 1.9 per cent) and the stroma of both corneas displayed an apparent reduction in keratocyte density (lens-wearing eye 21 per cent; control eye 10 per cent). Folds were observed with the slitlamp biomicroscope and long, straight, dark, orthogonal lines were observed with the confocal microscope, in the posterior stroma of the oedematous lens-wearing eyes. Such features were not observed in the control eyes. The keratocytes appeared less distinct with greater levels of corneal oedema.
Conclusion: The apparent loss of keratocytes following overnight lens wear is an optical artefact that can be explained in terms of corneal oedema causing volumetric tissue expansion and a loss of optical clarity, which hampers keratocyte detection. These findings place the onus on researchers postulating a loss of stromal keratocytes following clinical interventions, such as contact lens wear, to account for the effects of oedema.
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http://dx.doi.org/10.1111/j.1444-0938.2002.tb03027.x | DOI Listing |
BMC Public Health
January 2025
Department of Research and Development, Central Denmark Region, The Prehospital Emergency Medical Services, Brendstrupgaardsvej 7, Aarhus N, 8200, Denmark.
Background: While most Danish citizens never or very rarely call the national emergency helpline, 1-1-2, a few citizens call very often. In this article, we attend to the often-unheard voices of frequent callers, exploring why these citizens call 1-1-2 and why they often do not feel helped.
Methods: The article is based on a mixed-methods study on citizens in the Central Denmark Region who had called 1-1-2 five or more times during a period of six months in 2023.
Int Ophthalmol
January 2025
Discipline of Optometry, University of KwaZulu-Natal, Durban, South Africa.
Aim: To determine the prevalence of keratoconus and its associated risk factors within the adult population of Trinidad and Tobago.
Method: A population-based cross-sectional study was conducted among adults in Trinidad and Tobago, utilizing the Keratoconus Risk Assessment Questionnaire (KRIS) for data collection. Data were exported to the Statistical Package for Social Sciences (SPSS) version 27 for analysis.
Arq Bras Oftalmol
January 2025
Department of Ophthalmology and Visual Sciences, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
Purpose: This study aimed to report the use, efficacy, and safety of intracameral voriconazole as an adjuvant treatment for deep fungal keratitis.
Methods: This was a prospective case series of seven eyes with fungal keratitis with anterior chamber involvement or a corneal ulcer refractory to conventional topical treatment. In addition to topical treatment with 0.
Arq Bras Oftalmol
January 2025
Ophthalmology and Visual Sciences Department, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
Purpose: This study aimed to modify scleral contact lenses to achieve a desired compression standard and to evaluate the effectiveness and reliability of the adjustments.
Methods: In this nonrandomized, noncomparative, and partially masked study Scleral contact lens fittings were analyzed in 20 eyes of 12 patients (50% women, 50% men) diagnosed with keratoconus. Participants were selected based on their need for scleral contact lenses (SCLs), which was determined in complete ophthalmological examinations.
Arq Bras Oftalmol
January 2025
Department of Ophthalmology, Guangdong Eye Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences. No. 106 Zhongshan Er Road, Guangzhou 510080, China.
Purpose: Although the orthokeratology effects on corneal biomechanics have been proven with clinical trials, reports of stiffness parameter change are scarce. This study investigated the short-term orthokeratology effects in pediatric myopia and compared stiffness parameter changes to those published in recent clinical investigations. This prospective study aimed to investigate corneal biomechanics changes induced by short-term overnight orthokeratology treatment, focusing on stiffness parameter at A1 and stress-strain index.
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