What Is Myopia (Nearsightedness)?

Miopia is a refractive error (nearsightedness) in which parallel light focuses in front of the retina, causing blurred distance vision with clear near vision. It results from excessive eye length (axial myopia) or too much optical power of the cornea/lens (refractive myopia). Diagnosis is by refraction and ocular biometry; management includes spectacles, contact lenses, myopia control strategies in children, and refractive surgery in adults. High or pathologic miopia increases risks of retinal detachment, myopic maculopathy, glaucoma, and cataract.

Key Points

• Miopia (myopia, nearsightedness) causes blurred distance vision and typically begins in childhood, progressing through adolescence.
• Axial elongation is the principal mechanism; high miopia (≤ −6.00 D or axial length ≥ 26 mm) confers sight-threatening risks.
• Diagnosis requires cycloplegic refraction in children, axial length measurement when monitoring progression, and dilated retinal examination.
• Evidence-based myopia control in children includes low-dose atropine (off-label in the US), orthokeratology, and center-distance multifocal soft contact lenses (MiSight is FDA-approved for slowing progression).
• Adults with stable miopia may be candidates for LASIK/PRK/SMILE or phakic IOLs; pathologic complications require retinal subspecialty care.
• ICD-10-CM: H52.11 (right eye), H52.12 (left eye), H52.13 (bilateral), H52.10 (unspecified eye).

Anatomy and Physiology

• The eye forms a focused image when the cornea and crystalline lens converge light onto the retina.
• In miopia, total optical power exceeds the focal length required for the axial length, or the globe is elongated.
• Accommodation (ciliary muscle contraction increasing lens power) aids near focus and can mask or exacerbate apparent refractive error in youth.

Etiology

• Axial elongation: most common; driven by scleral remodeling and vitreoretinal signaling during childhood growth.
• Refractive components: steep cornea (eg, keratoconus), increased lens power (eg, nuclear sclerosis, spherophakia), or transient lens index shifts (hyperglycemia).
• Risk factors: parental myopia (dose-dependent), East Asian ancestry, early age of onset, high educational intensity/near work, limited outdoor time, prematurity/retinopathy of prematurity sequelae.

Pathophysiology

• Sustained hyperopic defocus at the peripheral retina is hypothesized to stimulate axial elongation via biochemical pathways in the retina–RPE–choroid–sclera complex.
• High axial length stretches ocular tissues, predisposing to peripheral retinal degeneration (lattice), posterior staphyloma, lacquer cracks, myopic choroidal neovascularization (mCNV), and myopic traction maculopathy.
• Accommodation spasm can cause “pseudomyopia,” a transient myopic shift due to ciliary muscle overactivity.

Epidemiology

• In the US, myopia prevalence increased from 25.0% (1971–1972) to 41.6% (1999–2004) among persons aged 12–54 years [1].
• Onset is typically school age (6–12 years) with average progression until late teens; adult-onset miopia occurs, particularly with intensive near work.
• High myopia prevalence has risen; precise contemporary US estimates vary by cohort and definition.

Classification

• By magnitude:

  • Low: < −3.00 diopters (D)
  • Moderate: −3.00 to −5.75 D
  • High: ≥ −6.00 D (or axial length ≥ 26.0 mm)

• By mechanism:

  • Axial vs refractive (corneal, lenticular)
  • Pseudomyopia (accommodative spasm)

• By onset: congenital/infantile, school-age/juvenile, adult-onset

• By pathology: simple (non-pathologic) vs pathologic/degenerative myopia (with myopic maculopathy, posterior staphyloma, or tractional changes)

Symptoms and Signs

Simple/axial miopia

• Blurred distance vision; squinting; eye strain (asthenopia); headaches after prolonged near work.
• Night vision difficulties (night myopia) and halos if concurrent mild corneal irregularity or tear film instability.
• Children: sitting close to screens/board, rubbing eyes, reduced distance attention, normal near tasks.

High/pathologic miopia

• Reduced best-corrected acuity if macular changes present.
• Fundus: tessellated background, peripapillary atrophy, tilted disc, lacquer cracks, chorioretinal atrophy, posterior staphyloma, lattice degeneration; potential mCNV.
• Symptoms of retinal break/detachment: photopsias (flashes), sudden increase in floaters, curtain/shadow.

Pseudomyopia (accommodative spasm)

• Variable blur at distance, improves after cycloplegia; often associated with excessive near work or convergence spasm.

Refractive (lenticular/corneal) myopia

• Rapid myopic shift with nuclear sclerotic cataract (older adults) or with acute hyperglycemia; fluctuates with glucose control.

Complications

• Retinal tears and rhegmatogenous retinal detachment (RRD)
• Myopic maculopathy: chorioretinal atrophy, lacquer cracks, mCNV
• Myopic traction maculopathy, foveoschisis
• Early posterior subcapsular and nuclear cataract
• Open-angle glaucoma risk elevation (diagnosis nuanced due to disc tilt and peripapillary atrophy)

Diagnosis

Clinical evaluation

• History: age of onset, progression rate, family history, visual demands, near work habits, outdoor time, systemic diseases (eg, diabetes), medications (eg, topiramate).
• Visual acuity at distance/near; manifest refraction; cover testing for phoria/tropia.
• Children: cycloplegic refraction (eg, cyclopentolate 1% OU) to uncover latent hyperopia/pseudomyopia.
• Slit-lamp exam; intraocular pressure; dilated fundus exam with peripheral retinal evaluation for lattice/holes.

Imaging and laboratory testing

• Axial length by optical biometry (eg, partial coherence interferometry/swept-source) to quantify progression.
• Keratometry/corneal topography for irregular astigmatism/ectasia (keratoconus).
• Macular OCT for suspected myopic traction, foveoschisis, or mCNV.
• Ocular ultrasound for posterior staphyloma when media opaque.

Differential diagnosis

Treatment

Medical management

• Optical correction

  • Spectacles: single-vision lenses for distance; progressive addition or bifocals for presbyopes.
  • Contact lenses: soft spherical/toric; rigid gas permeable (RGP) for superior optics in irregular corneas. Emphasize hygiene; sleeping in contacts increases keratitis risk [2].

• Myopia control in children/adolescents (slowing progression)

  • Low-dose atropine ophthalmic drops (compounded 0.01–0.05% OU qhs). Evidence supports dose-dependent slowing of axial elongation and refractive progression [3][4]. In the US, low-dose atropine for myopia is off-label; counsel on photophobia/near blur at higher doses and need for UV protection.
  • Center-distance multifocal soft contact lenses: MiSight 1 day is FDA-approved to slow myopia progression in children who start treatment age 8–12 [5]. Other center-distance multifocal designs are used off-label.
  • Orthokeratology (overnight corneal reshaping with RGP): reduces progression on average in controlled studies; off-label in the US. Requires strict hygiene and follow-up due to microbial keratitis risk [2][6].
  • Spectacle lens designs inducing peripheral myopic defocus (eg, DIMS/H.A.L.T.) show efficacy internationally; US regulatory status and availability are evolving.
  • Lifestyle: increasing outdoor time (≈2 hours/day) lowers risk of myopia onset; effect on progression is smaller and variable [7][8].

• Pathologic complications

  • Myopic choroidal neovascularization: intravitreal anti-VEGF. Ranibizumab 0.5 mg intravitreal is FDA-approved for mCNV; initial injection with PRN re-treatment based on activity [9]. Aflibercept is commonly used off-label.
  • Inflammatory/tractional sequelae: guided by retina subspecialist; OCT-directed management.

Procedural and surgical management

• Refractive surgery (adults with stable refraction, adequate corneal thickness/topography)

  • LASIK/PRK for low-to-moderate miopia; SMILE for selected ranges.
  • Phakic IOL (eg, posterior chamber ICL) for higher myopia or thin corneas.
  • Clear lens extraction is rarely chosen in young adults due to loss of accommodation; consider in very high myopia or when cataract present.
  • Contraindications: keratoconus/ectasia risk, active ocular surface disease, pregnancy/lactation, unstable refraction.

• Retina procedures

  • Laser retinopexy for symptomatic retinal tears; not for asymptomatic lattice without risk factors per standard practice [10].
  • Pars plana vitrectomy for macular traction/foveoschisis when visually significant.
  • Photodynamic therapy (verteporfin) is a secondary option for mCNV when anti-VEGF is unsuitable [10].

Special populations

• Pediatric: prioritize evidence-based myopia control, cycloplegic refraction, and axial length monitoring. Address binocular vision and near work ergonomics.
• Pregnancy/lactation: defer elective refractive surgery; transient refractive shifts occur. Avoid atropine for myopia control during pregnancy; limited data in lactation—consider alternatives or defer [3][9].
• Immunocompromised/contact lens users: heightened infection risk; prefer spectacles or meticulous lens hygiene; prompt evaluation for red, painful eye.
• Older adults: consider cataract-induced myopic shift when planning surgery and IOL power; screen for glaucoma and myopic maculopathy.

Prognosis

• Simple miopia is highly correctable with lenses; progression often slows after late adolescence.
• Early onset, faster yearly progression, and parental myopia predict higher adult refractive error.
• High/pathologic miopia increases lifetime risks of RRD, myopic maculopathy, cataract, and glaucoma; regular dilated retinal exams and prompt care for symptoms improve outcomes [1][10].

Prevention and Patient Counseling

• Encourage outdoor time in children; schedule regular eye examinations (annual for progressing youth; at least every 1–2 years for stable adults, more often in high myopia).
• Near work ergonomics: appropriate working distance, good lighting, frequent breaks (eg, 20-20-20 rule).
• Contact lens hygiene: daily replacement where possible; no overnight wear unless explicitly prescribed; avoid water exposure.
• High myopia: educate on warning symptoms of retinal tear/detachment and need for urgent evaluation.

When to Seek Immediate Care

• Sudden flashes of light, new or many floaters, or a curtain/shadow in vision
• Sudden, severe vision loss in one or both eyes
• Painful, red eye in a contact lens wearer
• Eye injury or blunt trauma
• Severe eye pain with headache and halos after starting a new medicine such as topiramate

References

1. Vitale S, Sperduto RD, Ferris FL III. Increased prevalence of myopia in the United States between 1971–1972 and 1999–2004. Arch Ophthalmol. 2009;127(12):1632-1639. doi:10.1001/archophthalmol.2009.303.
2. AAO EyeWiki. Contact Lens-Related Keratitis. Accessed July 2026. https://eyewiki.org/Contact_Lens-Related_Keratitis
3. AAO Preferred Practice Pattern. Pediatric Eye Evaluations PPP, and Refractive Errors & Refractive Surgery PPP. San Francisco, CA: American Academy of Ophthalmology; 2022–2023. https://www.aao.org/preferred-practice-pattern
4. Wei S, Li S, An W, et al. Safety and efficacy of low-dose atropine for myopia control: a meta-analysis. Ophthalmology. 2020;127(11):1530-1541. doi:10.1016/j.ophtha.2020.03.033.
5. U.S. FDA. FDA approves first contact lens indicated to slow the progression of nearsightedness in children. Press release. Nov 15, 2019. https://www.fda.gov/news-events/press-announcements/fda-approves-first-contact-lens-indicated-slow-progression-nearsightedness-children
6. Bullimore MA, Johnson LA. Overnight orthokeratology. Cont Lens Anterior Eye. 2020;43(3):322-332. doi:10.1016/j.clae.2019.11.004.
7. He M, Xiang F, Zeng Y, et al. Effect of time spent outdoors at school on the development of myopia. JAMA. 2015;314(11):1142-1148. doi:10.1001/jama.2015.10803.
8. AAPOS. Myopia and myopia control. Accessed July 2026. https://aapos.org/glossary/myopia-and-myopia-control
9. DailyMed. Ranibizumab injection label (Lucentis). Indications include myopic choroidal neovascularization. Accessed July 2026. https://dailymed.nlm.nih.gov
10. AAO Preferred Practice Pattern. Posterior Vitreous Detachment, Retinal Breaks, and Lattice Degeneration; and Age-Related Macular Degeneration/Retinal Vascular PPPs (sections on mCNV management). American Academy of Ophthalmology; 2019–2023. https://www.aao.org/preferred-practice-pattern

This article is for informational purposes and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified eye care professional about your specific condition. If you have sudden vision loss, severe eye pain, or an eye injury, seek emergency care immediately.