How should myopia be assessed and managed?

Assessment and Management of Myopia

Assessment of Myopia

All patients with suspected myopia require quantification of refractive error through comprehensive refraction to determine spherical equivalent and identify any astigmatic component. 1

Classification by Severity

• Low to moderate myopia: Less than 6.00 D spherical equivalent 1
• High myopia: 6.00 D or greater spherical equivalent 1
• Assess axial length measurements, particularly in progressive cases and children, as this provides objective data on eye growth 2

Risk Stratification

• High myopia patients require counseling about increased lifetime risks: retinal detachment, glaucoma, myopic macular degeneration, choroidal neovascularization, and cataract 1
• Screen for pathologic changes including peripheral retinal degeneration, choroidal thinning, and early glaucomatous changes 1
• Recognize that myopia typically appears between ages 6-12 years with average progression of 0.50 D per year in Caucasian children, though ethnic Chinese children show higher progression rates 1

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Management Strategy by Age Group

Children and Adolescents: Active Myopia Control

For school-age children with progressive myopia, combine low-dose atropine (0.01-0.05%) with multifocal daily disposable contact lenses (MiSight) as first-line therapy to achieve maximum slowing of progression. 3

First-Line Interventions (in order of efficacy):

Pharmacological:

• Low-dose atropine 0.01-0.05% shows the largest positive effects for slowing progression 3, 2
• Requires compounding pharmacy in the United States 3
• Fewer side effects than 1% concentration used for amblyopia 3
• High-dose atropine (1%) provides superior control (MD 0.90 D at 1 year, MD 1.26 D at 2 years) but cycloplegic and mydriatic side effects limit use 2

Optical Interventions:

• MiSight FDA-approved daily disposable multifocal contact lenses for children 8-12 years who can safely handle lenses, with 6-year safety data showing no complications 3
• Orthokeratology reduces axial elongation by 32-63% over 2 years but carries microbial keratitis risk similar to overnight lens wear, with particular concern for Acanthamoeba when tap water is used 3, 2
• Multifocal spectacles (including Stellest defocus technology) provide modest benefit for children who cannot or will not use contact lenses or atropine 3, 2

Environmental Modification:

• Increase outdoor time to 1-2 hours daily to reduce progression 3
• Note: Outdoor time prevents myopia onset but does NOT slow progression once myopia is established 4

Interventions to AVOID:

• Undercorrection of myopia does NOT slow progression and should never be used as a control strategy 3, 2
• Timolol or IOP-lowering drops show no efficacy 3
• Visual training exercises lack scientific evidence 3
• Acupuncture and nutritional approaches have insufficient evidence 3

Safety Considerations for Contact Lens Wear:

• Daily disposable lenses have the lowest complication rates for soft contact lens wear 3
• Address contact lens safety in at-risk patients: eliminate overnight wear, convert from planned replacement to daily disposables, and switch from multipurpose solution to peroxide disinfection 1

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Adults: Optical Correction

For adults with stable myopia, prescribe eyeglasses as first-line correction because they represent the simplest and most cost-effective strategy. 1, 5

Optical Correction Options (in order of preference):

1. Eyeglasses:

   • First-line for all symptomatic refractive errors 1
   • Use high-index lenses for myopia ≥6.00 D to reduce thickness and weight 5
   • Full correction recommended for optimal visual function 1

2. Contact Lenses:

   • Consider after eyeglasses have been evaluated 1
   • Soft hydrogel or silicone hydrogel lenses used by 93% of contact lens wearers 5
   • Rigid gas-permeable lenses as alternative option 5

3. Refractive Surgery:

   • LASIK and other corneal refractive procedures for appropriate candidates 1, 5
   • Over 13 million LASIK procedures performed in the United States 1
   • Consider only after non-surgical options discussed 5

Adult-Onset Myopia:

• Represents one-third or more of all myopia in Western populations 6
• Clinically meaningful progression continues in early adulthood, averaging 1.00 D between ages 20-30 years 6
• Higher myopia levels carry greater absolute risk of myopia-related ocular disease requiring ongoing management 6

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Special Considerations

Presbyopic Patients with Myopia:

• Offer bifocal, trifocal, or progressive addition lenses for combined distance and near correction 1, 5
• Consider multifocal contact lenses (soft or rigid gas-permeable with aspheric bifocal/multifocal optics) 7
• Pilocarpine HCl 1.25% (Vuity) is FDA-approved for presbyopia but requires mandatory dilated retinal exam before initiation to rule out retinal holes, tears, or detachments 7

High Myopia (≥6.00 D):

• Inform patients about substantially increased lifetime risk of vision-threatening complications 1, 8
• Each additional 1 D of myopia increases risk: myopic maculopathy by 58%, open-angle glaucoma by 20%, posterior subcapsular cataract by 21%, and retinal detachment by 30% 8
• Schedule more frequent monitoring for pathologic changes 1

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Risk-Benefit Analysis of Myopia Control

The benefits of slowing myopia progression by 1 D substantially outweigh treatment risks: the number needed to treat to prevent 5 years of visual impairment is 4.1 to 6.8, whereas fewer than 1 in 38 patients will experience vision loss from myopia control interventions. 8

• Predicted mean years of visual impairment ranges from 4.42 years with -3 D myopia to 9.56 years with -8 D myopia 8
• A 1-D reduction lowers these by 0.74 and 1.21 years, respectively 8
• Risk of microbial keratitis with contact lens wear: 1-25 per 10,000 patient-years, with 15% resulting in vision loss 8