RESUMO
Orthokeratology offers the unique possibility of correcting myopia: a special reverse geometry contact lens used exclusively during sleeping hours at nighttime. The authors give a comprehensive overview about the evolving technique, including the careful selection of patients, and practical contact lens fitting. They explain a series of daily life situations and point out dos and don'ts. Limitations of orthokeratology are highlighted with regard to refraction errors and anatomical conditions. Early regression and glare due to corneal aberrations are common negative side effects. Critical complications like bacterial keratitis, ocular surface disorders, and morphologic changes through corneal molding as corneal hypoesthesia and ferritin deposits are considered. Emerging applications are discussed: correction of presbyopia, corneal crosslinking to stabilize the ortho-k effect, myopia control in children, topographically controlled and individualized contact lens geometries using advanced contact lens materials. Legal regulations concerning the driving permission are outlined. Nevertheless, orthokeratology seems to be a well-established niche technology predominantly useful in young, healthy, and active myopic patients. The fitting and care of this refractive tool is demanding and costly. However, these lenses fill the gap between every day conventional contact lens and surgical refractive methods. Another growing application of high interest is myopia control in children.
Assuntos
Lentes de Contato , Miopia , Procedimentos Ortoceratológicos , Erros de Refração , Criança , Córnea , Topografia da Córnea , Humanos , Miopia/diagnóstico , Miopia/terapia , Refração Ocular , Acuidade VisualRESUMO
In times of unlimited availability of exchange lenses on the internet and in discount stores, the contact lens has increasingly become a lifestyle but also a disposable product. The targeted marketing of the contact lens as a mass product could only be realized because the fitting and application of the contact lenses are presented as very simple. The numbers of contact lens-induced complications, as well as the fact that the German market in particular has not seen any increase in the number of contact lens wearers in recent years (2015 to 2019), however, speak a different language.How to fit your patient correctly after a detailed explanation of the different types of contact lenses and their areas of application, how to instruct him or her on how to use them correctly and what risks the patient must be informed about is the subject of this 2nd part of "The basics of practical contact lens fitting". It also explains how to avoid complications that can occur when wearing contact lenses and how to advise and care for patients with contact lens intolerances.
Assuntos
Lentes de Contato Hidrofílicas , Lentes de Contato , Lentes de Contato/efeitos adversos , Lentes de Contato Hidrofílicas/efeitos adversos , Feminino , Humanos , Masculino , Ajuste de PróteseRESUMO
The great potential of contact lenses for improving vision in all forms of corneal irregularities, e.âg. keratoconus, after keratoplasty, after keratitis, is in danger of being forgotten. Especially by the younger generation of ophthalmologists and opticians there is a risk that the skill of fitting contact lenses professionally will be lost. There are many situations in which the practicing ophthalmologist should recognize that the contact lens can be a useful option for the visual rehabilitation of his patient. In this article, we provide a summary of "The basics of practical contact lens fitting". The first part is about materials, fields of application and differences in optics compared to glasses.
Assuntos
Lentes de Contato , Transplante de Córnea , Ceratocone , Córnea , Humanos , Ceratocone/cirurgia , Ajuste de Prótese , Acuidade VisualRESUMO
INTRODUCTION: Myopia is a major cause of degenerative eye disease and increases the risk of secondary visual impairment. Mitigating its progression therefore has great potential of clinically relevant benefit as shown by using highly diluted atropine eye drops in children of Asian origin. However, limited evidence is available regarding the efficacy and safety of low-dose atropine therapy in non-Asian populations. Hence, the Low-dose AtropIne for Myopia Control in Children (AIM) study will test the efficacy and safety of 0.02% atropine vs placebo in a German population. METHODS AND ANALYSIS: AIM is a national, multicentre, prospective, randomised, placebo-controlled, double-blind trial with two parallel arms. The primary objective is to assess the efficacy of atropine 0.02% eyedrops for myopia control in children of Caucasian origin. The primary outcome is the change in cycloplegic refraction after 1 year of treatment (D/year). Secondary and tertiary outcome measures comprise the change in axial length (mm/year) in children treated with 0.02% atropine compared with placebo, the myopic progression of participants treated with 0.01% compared with 0.02% atropine (D/year and mm/year), and the safety profile of both 0.02% and 0.01% atropine. Furthermore, the myopic progression 1 year after cessation of therapy with 0.02% atropine will be evaluated. Inclusion criteria are an age of 8-12 years and myopia of -1 D to -6 D with an estimated annual myopia progression of ≥0.5 D. After randomisation, patients will receive either atropine 0.02% (arm A) or placebo eye drops (arm B) in the first year of treatment. In the second year, they will continue to receive atropine 0.02% (arm A) or switch to atropine 0.01% (arm B). In the third year, they will switch to placebo (arm A) or continue with atropine 0.01% (arm B). To achieve a statistical power of 80%, the calculated sample size is 300. The trial has started in October 2021 with a planned recruitment period of 18 months. ETHICS AND DISSEMINATION: AIM has been approved by the Central Ethics Committee of the University Medical Center Freiburg (21-1106), local ethics committees of each participating centre and the German Federal Institute for Drugs and Medical Devices (61-3910-4044659). It complies with the Declaration of Helsinki, local laws and ICH-GCP. Results and underlying data from this trial will be disseminated through peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT03865160.