Search results for "Cycloplegia"
showing 9 items of 9 documents
Accuracy and accommodation capability of a handheld autorefractor
2000
Purpose: To determine the accuracy of measurement by the Nikon Retinomax handheld autorefractor and its ability to relax accommodation. Setting: Pediatric Section, Department of Ophthalmology, University of Mainz, Germany. Methods: To perform a series of comparative measurements, autorefractor readings were obtained on healthy young adults (students) and on children aged 2 to 12 years. The autorefractor readings were compared with subjective refractions of the young adults and with cycloplegic retinoscopy of the children. Results: In adults, the accuracy of the handheld autorefractor measurements was comparable to that of conventional tabletop autorefractors. In children, the autorefractor …
Risk factors for high myopia: a 22‐year follow‐up study from childhood to adulthood
2018
PURPOSE To determine the effect of the definition of high myopia on its prevalence and risk factors for high myopia. METHODS A total of 240 myopic schoolchildren (119 boys and 121 girls) at the mean age of 10.9 years (range 8.8-12.8 years) were recruited to a randomized clinical trial of myopia treatment among children from 3rd- and 5th grades of school referred for an eye examination due to poor distant vision and having no previous spectacles. Clinical follow-ups, including refraction with cycloplegia, were conducted annually at 3 years [third follow-up here = clinical follow-up 1, (n = 237)], and thereafter twice at approximately 10-year intervals [clinical follow-ups 2 (n = 179) and 3, …
Comparison of partial coherence interferometry and ultrasound for anterior segment biometry.
2008
To assess the performance of a partial coherence interferometry (PCI)-based device for the determination of anterior segment biometry.Clinica Centrofama, Cartagena, Murcia, Spain.Central corneal thickness (CCT), anterior chamber depth (ACD), and lens thickness (LT) were measured with the ACMaster PCI anterior segment biometer and an Echoscan US-1800 ultrasound (US) biometer/pachymeter with and without cycloplegia. To determine the precision of the instruments, the same examiner took 30 consecutive CCT, ACD, and LT measurements in a single subject under the same conditions and with and without cycloplegia. The same measurements were performed in additional subjects.Twenty-one eyes (16 subjec…
Prevalence of refractive errors in the European adult population: the Gutenberg Health Study (GHS).
2014
Objective To study the distribution of refractive errors among adults of European descent. Design Population-based eye study in Germany with15 010 participants aged 35–74 years. Methods The study participants underwent a detailed ophthalmic examination according to a standardised protocol. Refractive error was determined by an automatic refraction device (Humphrey HARK 599) without cycloplegia. Definitions for the analysis were myopia +0.5 D, astigmatism >0.5 cylinder D and anisometropia >1.0 D difference in the spherical equivalent between the eyes. Exclusion criterion was previous cataract or refractive surgery. Results 13 959 subjects were eligible. Refractive errors ranged from −21.5 to…
Comparison of myopic progression in Finnish and Singaporean children
2020
Purpose To compare 3-year myopic progression between Finnish and Singaporean children. Methods Myopic progression was compared between 9-year-old (mean age 9.7 ± 0.4 years, n = 92) and 11-year-old (mean age 11.7 ± 0.4 years, n = 144) Finnish (Finnish RCT) children and Singaporean children matched by age and refraction (SCORMMatched, n = 403) and 7- to 8-year-old Singaporean children matched only by refraction (SCORM Young, n = 186). Spherical equivalent (SE) was between −0.50 and −3.00 D. Refraction with cycloplegia was controlled annually for 3 years. Information on parental myopia, mother’s education, time spent on near-work and outdoor time was gathered by parental questionnaire. Results…
Accommodation-related changes in monochromatic aberrations of the human eye as a function of age.
2008
PURPOSE. To investigate the relationship between accommodation and the optical aberrations of the whole human eye, as a function of age. METHODS. Sixty healthy subjects with spherical ametropia in the range 3 D, astigmatism less than 1 D, corrected visual acuity of 20/18 or better, and normal findings in an ophthalmic examination were enrolled. Subjects were divided into four groups, with age ranges of 19 to 29, 30 to 39, 40 to 49, and 50 to 60 years. Monochromatic optical aberrations and pupil size were measured with a Hartmann-Shack wavefront sensor under monocular viewing conditions, without pharmacological dilation or cycloplegia. Stimulus vergences were in the range of 0 to 5 D, with a…
Superdiluted atropine at 0.01% reduces progression in children and adolescents. A 5 year study of safety and effectiveness
2018
Abstract Objective To confirm the clinical security and effectiveness of the daily application of 0.01% superdiluted atropine eyedrops in the progression of myopia in children. Material and methods A total of 200 children 9–12 years of age were randomized into a treated group and a control without treatment. Refraction under cycloplegia was performed. Results Myopia progression of the treated group was −0.14 ± 0.35 versus −0.65 ± 0.54 in the control group without treatment. Only 2% of patients were forced to stop treatment due to side effects. Conclusion Atropine superdiluted atropine 0.01% eyedrops is effective and well tolerated, and reduced myopia progression by 25%.
Effect of Phenylephrine on the Accommodative System
2016
Accommodation is controlled by the action of the ciliary muscle and mediated primarily by parasympathetic input through postganglionic fibers that originate from neurons in the ciliary and pterygopalatine ganglia. During accommodation the pupil constricts to increase the depth of focus of the eye and improve retinal image quality. Researchers have traditionally faced the challenge of measuring the accommodative properties of the eye through a small pupil and thus have relied on pharmacological agents to dilate the pupil. Achieving pupil dilation (mydriasis) without affecting the accommodative ability of the eye (cycloplegia) could be useful in many clinical and research contexts. Phenylephr…
Effect of Cycloplegia on Blur Perception Thresholds as Measured by Source Method
2017
Abstract One of the advantages of a source method over observer method in blur perception measurements is better control of a stimulus blur level, which is achieved with computerised image processing unlike the observer method that requires optical defocusing of the observer. The aim of this study was to determine if paralysation of accommodation has effect on blur perception thresholds, thereby evaluating its necessity in such experiments. Blur perception thresholds (just noticeable blur, clear image, recognition, and non-resolvable blur thresholds) were evaluated with (using cycloplegia) and without paralysed accommodation to determine effect on blur perception. A computerised low-pass sp…