PURPOSE To describe spherical equivalent (sph eq) refractive errors in preschool members of a Native American tribe with a high prevalence of astigmatism. METHODS Cycloplegic autorefraction measurements were obtained for 819 three- and four-year-old Tohono O'odham children, with follow-up measurements in 146 after 4 to 8 years. RESULTS Mean sph eq was significantly more hyperopic in the ast...

In 1995, a 46-year-old woman was referred for refractive surgery. Eleven years earlier, she had undergone an uncomplicated penetrating keratoplasty in her right eye to treat a dense corneal opacity caused by contact lens-related microbial keratitis. Due to high myopia in the graft, she was unable to achieve useful vision and declined contact lens use. After extensive counseling, she elected to ...

PURPOSE To compare the agreement between subjective refraction and autorefraction using two commercially available autorefractors. METHODS Prospective data were collected for 190 subjects using either the Nidek ARK-700A (Fremont, CA) or the Topcon KR-8000 (Paramus, NJ) and subjective refraction (masked to autorefraction). Refractions were compared in terms of spherical equivalent using Bland-...

PURPOSE To evaluate the outcome after small incision refractive lenticule extraction (SMILE) in patients with myopic astigmatism. METHODS Seven hundred seventy-five eyes from 403 patients with myopia treated with SMILE for a cylinder of 0.75 diopters (D) or more were identified from patient records. Six hundred sixty-nine eyes were defined as receiving low (< 2.5 D) and 106 eyes as receiving ...

PURPOSE The relationship between astigmatic refractive errors and their associated visual acuity has been studied in recent years in the context of refractive power space. The influence of the axis of astigmatism remains a matter of controversy. Our goal in this study is to provide additional experimental evidence to clarify this subject. The influence of the simulated axis orientation was comp...

AIMS This study aimed to evaluate stromal wound healing morphology in short term unsutured compared with sutured corneal wounds, to define regional variation in healing within radial keratotomy wounds. METHODS Stromal scar tissue orientation (fibroblast and collagen fibre orientation) was analysed in unsutured and adjacent sutured keratotomy wounds in monkeys, 2 to 9 weeks after surgery, usin...

Since the introduction of radial keratotomy, accurate incision depth has been difficult to achieve with any corneal knife. To assure repeatable depth of incisions and to adjust the refractive effect of these incisions after the surgery, I have developed a series of techniques that are described in this article and that I refer to as "tickles" in discussion with the patients. Seventeen eyes, fro...