Ratings of importance to the care process (A-C) and ratings of strength of evidence (I-III) are defined at the end of the "Major Recommendations" field.
Diagnosis
The evaluation of refractive errors requires an assessment of both the refractive status of the eye, the patient's current mode of correction, symptoms, and visual needs. [A:III]
History
The history should incorporate the elements of the comprehensive adult medical eye evaluation in order to consider the patient's visual needs and any ocular pathology [A:III]
Examination
Distance visual acuity should be measured separately for each eye with current correction. [A:III]
The refraction of each eye should be evaluated independently, either objectively by retinoscopy, with an autorefractor, or with a wavefront analyzer; or it may be done subjectively. [A:III] In cooperative patients, subjective refinement of refraction using a phorometer or trial lens set is preferred. [B:III] Distance refraction should be performed with accommodation relaxed. [B:III] Near vision should be measured in each eye before cycloplegia for patients with high hyperopia, presbyopia, or complaints about near vision. [B:III]
Management
Eyeglasses
Patients with low refractive errors may not require correction; small changes in refractive corrections in asymptomatic patients are generally not recommended. [A:III] Eyeglasses are the simplest and safest means of correcting a refractive error; therefore eyeglasses should be considered before contact lenses or refractive surgery. [A:III] A patient's eyeglasses and refraction should be evaluated whenever visual symptoms develop. [A:III]
Safety glasses or eye protectors are strongly recommended for individuals involved in certain sports (e.g., racquetball, squash) and hazardous activities in which there is risk of flying particles (e.g., using hammers, saws, weed trimmers) (American Academy of Pediatrics and American Academy of Ophthalmology, 2003) [A:III] They are also recommended for all individuals with good vision in only one eye. [A:III] When ocular protection is the foremost consideration, polycarbonate plastic is the material of choice, because it is much more impact resistant than regular plastic or hardened glass (Vinger et al., 1997) [A:I]
Contact Lenses
Before contact lens fitting, an ocular history including past contact lens experience should be obtained and a comprehensive medical eye evaluation should be performed (see the National Guideline Clearinghouse [NGC] summaries of the American Academy of Ophthalmology [AAO] Preferred Practice Patterns Comprehensive adult medical eye evaluation and Pediatric eye evaluations: I. Screening. II. Comprehensive ophthalmic evaluation). [A:III] Patients should be made aware that using contact lenses can be associated with the development of ocular problems, including microbial corneal ulcers that may be vision threatening, and that overnight wear of contact lenses is associated with an increased risk of ulcerative keratitis (Mondino et al., 1986; Poggio et al., 1989; Stehr-Green et al., 1987) [A:II] The increased risk of ulcerative keratitis with extended contact lens wear should be discussed with patients who are considering this modality of vision correction (Poggio et al., 1989) [A:I] Before being fitted with overnight wear contact lenses, patients should be informed of their responsibilities and the increased risks of overnight wear compared with daily wear.[A:III]
The United States Food and Drug Administration has made the following recommendations for contact lens wearers regarding proper lens care practices (U.S. Food and Drug Administration, 2007) [A:III]
- Wash hands with soap and water, and dry (lint-free method) before handling contact lenses.
- Wear and replace contact lenses according to the schedule prescribed by the doctor.
- Follow the specific contact lens cleaning and storage guidelines from the doctor and the solution manufacturer.
- Keep the contact lens case clean and replace every 3 to 6 months.
- Remove the contact lenses and consult your doctor immediately if you experience symptoms such as redness, pain, tearing, increased light sensitivity, blurry vision, discharge, or swelling.
First-time daily-wear or extended-wear contact lens users should be checked soon after the contact lenses are initially dispensed. [A:III] Experienced contact lens users should generally be examined annually. [A:III]
Keratorefractive Surgery
Preoperative Evaluation
A comprehensive medical eye evaluation should be performed before any refractive surgery procedure. [A:III] In addition to the elements listed in the comprehensive adult medical eye evaluation (see the NGC summary of the AAO Preferred Practice Pattern Comprehensive adult medical eye evaluation), the refractive surgery examination should also include the following elements: [A:III]
- Visual acuity without correction
- Manifest, and where appropriate, cycloplegic refraction
- Computerized corneal topography
- Central corneal thickness measurement
- Evaluation of tear film
- Evaluation of ocular motility and alignment (Snir et al., 2003)
The patient should be informed of the potential risks, benefits, and alternatives to and among the different refractive procedures before surgery. [A:III] The informed consent process should be documented, and the patient should be given an opportunity to have all questions answered before surgery. [A:III]
Refer to the original guideline document for detailed management recommendations.
Postoperative Care
Postoperative management is integral to the outcome of any surgical procedure and is the responsibility of the operating surgeon (American Academy of Ophthalmology and American Society of Cataract and Refractive Surgery, 2000; American Academy of Ophthalmology, 2006) [A:III]
For patients undergoing refractive surgery with surface ablation techniques, postoperative examination, including slit-lamp biomicroscopy of the cornea, is advisable on the day following surgery and every 2 to 3 days thereafter until the epithelium is healed. [A:III]
For patients who have had uncomplicated laser in situ keratomileusis (LASIK) surgery, postoperative examination should be performed within 48 hours following surgery, a second visit should be performed 1 to 4 weeks postoperatively, and further visits thereafter as appropriate. [A:III]
Intraocular Refractive Surgery
Preoperative Evaluation
A comprehensive medical eye evaluation should be performed before any refractive surgery procedure. [A:III] In addition to the elements listed in the comprehensive adult medical eye evaluation (see the NGC summary of the AAO Preferred Practice Pattern Comprehensive adult medical eye evaluation), the intraocular refractive surgery examination includes the following elements in the table below.
Achieving the targeted postoperative refraction for refractive lens exchange requires measuring axial length accurately, determining corneal power, and using the most appropriate intraocular power formula for that eye. [A:III]
Table. Elements of the Intraocular Refractive Surgery Preoperative Evaluation [A:III]
Element |
Phakic Intraocular Lens (IOL) Implantation |
Refractive Lens Exchange |
Computerized corneal topography |
Optional |
Yes |
Central corneal thickness measurement |
Yes |
Optional |
Axial length |
Optional* |
Yes |
White-to-white measurement of the limbus |
Yes |
Optional |
Specular microscopy/confocal microscopy |
Yes |
Optional |
Anterior chamber depth |
Yes |
Yes |
Pupil size |
Yes |
Yes |
* The surgeon should be prepared to implant a pseudophakic IOL in the case that there is significant damage to the lens during phakic lens implantation.
Refer to the original guideline document for detailed management recommendations.
Postoperative Care
Components of each postoperative examination should include: [A:III]
- Interval history, including use of postoperative medications, new symptoms, and self-assessment of vision
- Measurement of visual function (e.g., visual acuity, pinhole testing)
- Measurement of intraocular pressure
- Slit-lamp biomicroscopy
- Counseling/education
- Management plan
Provider
Patients with refractive errors should be examined and evaluated for treatment by an ophthalmologist or an optometrist. [A:III] Surgical treatment of refractive errors, including excimer laser surgery, should be performed only by an appropriately trained ophthalmologist. [A:III]
Counseling/Referral
Any decisions about surgical correction of a refractive error should be made by an informed patient and an ophthalmologist familiar with refractive surgery. [A:III] Information and discussion about the planned procedure should be available sufficiently in advance of the proposed surgical date so that the patient can carefully consider the risks, benefits, and alternatives to the procedure. [A:III]
Definitions:
Rating of Importance to the Care Process
Level A, defined as most important
Level B, defined as moderately important
Level C, defined as relevant but not critical
Rating of Strength of Evidence
Level I: Includes evidence obtained from at least one properly conducted, well-designed randomized controlled trial. It could include meta-analyses of randomized controlled trials.
Level II: Includes evidence obtained from the following:
- Well-designed controlled trials without randomization
- Well-designed cohort or case-control analytic studies, preferably from more than one center
- Multiple-time series with or without the intervention
Level III: Includes evidence obtained from one of the following:
- Descriptive studies
- Case reports
- Reports of expert committees/organization (e.g., Preferred Practice Patterns [PPP] Panel consensus with external peer review)