Management of Refractive Errors
Eyeglasses are the first-line treatment for all refractive errors (myopia, hyperopia, astigmatism, and presbyopia), representing the simplest and most cost-effective correction strategy before considering contact lenses or surgical options. 1, 2
Treatment Algorithm by Modality
Primary Correction: Eyeglasses
- All patients with symptomatic refractive errors should initially be offered eyeglasses as they provide the most straightforward, protective, and economical solution 1, 3
- For hyperopia in young/middle-aged patients, slight undercorrection may be preferable due to physiologic accommodative tone, but full correction becomes necessary with aging to optimize both distance and near vision 1
- For astigmatism, full cylindrical correction effectively treats both with-the-rule and against-the-rule types, though adults with previously uncorrected astigmatism require gradual correction to improve tolerance 2
- High refractive errors (≥3.00 D hyperopia, ≥6.00 D myopia, ≥3.00 D astigmatism) should utilize high-index lenses to reduce thickness, weight, and improve cosmetic appearance 1, 3
- For presbyopia, bifocals, trifocals, or progressive addition lenses are appropriate options 4, 3
Secondary Correction: Contact Lenses
Contact lenses should only be considered after eyeglasses have been evaluated as the primary option. 1, 4
Lens Selection by Refractive Error Type:
- Spherical errors (myopia/hyperopia): Soft hydrogel or silicone hydrogel lenses are most commonly used (93% of contact lens wearers), with rigid gas-permeable lenses as an alternative 1, 3
- Low to moderate astigmatism (<3.00 D): Soft toric contact lenses or rigid gas-permeable lenses effectively correct these errors 2, 3
- High astigmatism (≥3.00 D): Rigid gas-permeable, hybrid, or custom-designed soft toric lenses provide optimal correction, with bitoric or back-surface toric designs minimizing corneal bearing 2, 3
- Irregular astigmatism: Rigid gas-permeable scleral lenses (diameter >17 mm) are excellent for high and/or irregular astigmatism, particularly with anisometropia 2, 3
Critical Safety Considerations:
- Daily disposable lenses are the safest modality, causing less ocular surface damage and lower proinflammatory cytokine levels compared to reusable lenses 3
- For patients at risk or with history of contact lens complications: eliminate extended wear (overnight wear), convert from planned replacement to daily disposable lenses, and/or switch from multipurpose solution to peroxide disinfection systems 3
- Adequate contact lens movement is essential for comfortable wear and maintenance of corneal integrity 3
Tertiary Correction: Surgical Options
Surgical correction should only be considered after non-surgical options have been evaluated. 1
Surgical Modalities by Indication:
- LASIK is a viable corneal refractive surgery option for myopia, hyperopia, and astigmatism 1, 3
- PRK (Photorefractive Keratectomy) involves removing central corneal epithelium and using excimer laser ablation, with mitomycin-C 0.02% often used off-label for approximately 15 seconds to reduce corneal subepithelial haze, particularly with high corrections 2
- Axis alignment is critical for astigmatism correction: reference marks must be placed on the operative eye while the patient is seated upright before laser procedures to compensate for ocular cyclotorsion, as misalignment significantly reduces treatment effectiveness 2
- Lens-based surgery (clear lens extraction, phakic intraocular lenses) is an option for high refractive errors 1
- For presbyopia: excimer laser photoablation is the most widely used surgical approach, with monovision surgery appropriate for patients over 40 who prioritize freedom from optical aids and are willing to sacrifice uncorrected distance stereoacuity 4
Absolute Contraindications to Refractive Surgery:
- Insufficient corneal thickness for proposed ablation depth 2
- Significant irregular astigmatism (relative contraindication) 2
Pharmacological Treatment (Presbyopia Only)
- Pilocarpine HCL 1.25% (Vuity) is the only FDA-approved topical therapy for daily treatment of presbyopia, acting by stimulating ciliary muscle contraction and promoting miosis 4
- Mandatory dilated eye exam before initiating pilocarpine to identify retinal holes, tears, or detachments, as retinal detachment and retinal tear have been reported with miotics 4
- Patients with pre-existing retinal disease are at increased risk of complications 4
Myopia Prevention and Control in Children
- Consider low-dose atropine and increased outdoor time for myopia prevention in young children at risk 3
- For school-age children with myopia progression: consider antimuscarinic agents, multifocal spectacles or contact lenses, and orthokeratology for myopia control 3
Common Pitfalls to Avoid
- Never attempt full cylindrical correction immediately in adults with previously uncorrected astigmatism, as this leads to poor tolerance; gradual correction is better accepted 2
- Undercorrection in older adults with hyperopia compromises both distance and near vision; full correction is necessary for optimal visual outcomes 1
- Never initiate pilocarpine without a prior dilated eye exam due to risk of retinal detachment in patients with pre-existing retinal pathology 4
- Avoid monovision surgery in patients with history of strabismus surgery or ocular deviations due to risk of post-operative diplopia 4
- Failing to compensate for cyclotorsion during refractive surgery results in axis misalignment and reduced astigmatic correction 2
- Irregular astigmatism cannot be fully corrected with spherocylindrical lenses and requires specialty contact lenses or surgical intervention 2