A 16-year-old girl is brought to clinic for vision follow-up. The patient has myopia that was diagnosed at age 8. She wears corrective lenses, and her prescription has progressed yearly. The patient has no other chronic medical conditions and takes no daily medications. Vital signs are normal. Examination shows equal pupillary reflexes. Visual acuity is 20/50 bilaterally with current lenses. Refraction testing results in a lens prescription of −9 diopters sphere in the right eye and −8.75 diopters sphere in the left eye. This patient is at increased risk for which of the following complications?
Myopia (nearsightedness) | |
Pathophysiology |
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Epidemiology |
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Clinical features |
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Management |
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Complications* |
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*Associated with high myopia (ie, ≥6 diopters of correction). | |
This patient has progressive myopia (nearsightedness), a refractive error most commonly caused by increased anterior-posterior diameter of the eye. As the axial length of the eye increases during adolescence, the risk of myopia also increases because the focal point of a refracted image shifts anterior to the retina. The image displacement causes blurred distance vision, although vision of nearby objects is normal. Examination shows decreased visual acuity; peripheral field testing and funduscopic examination are normal. Management of myopia is with prescription lenses with a diverging (concave) lens, which refocuses the refracted image onto the retina.
Patients with progressive myopia (ie, untreated or refractory to treatment) may develop high myopia, which is characterized by needing ≥6 diopters of correction to achieve normal visual acuity, as seen in this patient. High myopia leads to stretching and thinning of the sclera, choroid, and retina. These mechanical changes are associated with an increased risk of retinal detachment and macular degeneration, both of which can lead to vision loss. Retinal detachment in high myopia is characterized by a retinal tear that allows vitreous fluid to accumulate between the retinal layers.
In some children, antimuscarinic drops (eg, atropine) or orthokeratology (ie, rigid contact lens) may be used to slow progressive myopia and prevent subsequent complications.
(Choice A) Hyphema, or blood within the anterior chamber, usually occurs due to blunt force trauma to the eye. Spontaneous hyphema is associated with underlying bleeding disorders (eg, von Willebrand disease) or microvascular disease (eg, diabetes), not high myopia.
(Choice B) Anterior uveitis (intraocular inflammation) can cause eye pain, redness, and vision loss. Associated conditions include infection (eg, herpes viruses) and autoimmune disease (juvenile idiopathic arthritis). The incidence is not increased with myopia.
(Choice C) Pterygium is a wedge-shaped proliferation of conjunctival tissue that expands from the lateral aspects of the eye toward the cornea. Patients typically have chronic ultraviolet light exposure; myopia is not associated with pterygium development.
(Choice E) Retinal microinfarctions are characterized by arteriolar obstruction leading to ischemia and are seen on funduscopy as yellow-white retinal lesions (cotton-wool spots). This condition is associated with hypertension and diabetes, not high myopia.
Educational objective:
Myopia, or nearsightedness, is characterized by increased anterior-posterior diameter of the eye, causing blurred distance vision. High myopia (≥6 diopters of correction) increases the risk of retinal detachment and macular degeneration.