Extreme Nearsightedness: Dangers Beyond Coke Bottle Glasses
- Sophia Wong, MD
- May 12
- 6 min read
Updated: May 13
Did you know that being nearsighted, or myopic, can have vision implications beyond needing to wear thick glasses? Severe nearsightedness, called high myopia or pathologic myopia, can cause retinal damage that is not correctable with glasses. According to an article in the scientific journal Ophthalmology, the rate of myopia is predicted to affect half the world's population by 2050, with high myopia affecting approximately 10% (1). That's 938 million people with high myopia.
As rates of myopia climb worldwide, especially among younger populations, understanding the risks and management of high myopia has become more important than ever. In this post, we’ll explore the various retinal complications that can arise from high myopia, and the treatment options that are available to prevent or slow its progression.
What Is High Myopia?
Myopia is a refractive error that causes distant objects to appear blurry while close objects can be seen clearly. We call this nearsightedness, meaning the sight is focused at near or close up. Refractive error refers to the amount of correction or prescription that is needed in your lenses to optimize clear vision. Myopia occurs when the eye is too long from front to back (axial elongation), or the cornea is too curved, causing light to focus in front of the retina rather than directly on it. As a result, the image that is created on the retina is blurry and out of focus.
High myopia is defined as a refractive error of -6.00 diopters (D) or more, or an axial length of 26.5 mm or greater (the average axial length is 23-25 mm). Unlike low or moderate myopia, high myopia is associated with structural changes in the eye that increase the risk for serious retinal conditions such as bleeding inside the eye and retinal detachment.
The Myopia Epidemic
Myopia rates have skyrocketed over the past few decades, particularly in East Asia, where 80-90% of young adults are affected in some regions(2). This was exacerbated by the COVID-19 pandemic and attributed to time spent indoors . It's a looming challenge for public health systems due to the lifelong risks that high myopia brings.
Factors contributing to this epidemic include:
Increased near work (e.g., screen time and reading)
Decreased outdoor time
Genetic predisposition (children of myopic parents are more likely to be myopic)
How High Myopia Affects Eye Health
While standard myopia mainly causes blurred vision, high myopia can lead to irreversible vision loss due to its effects on the anatomy of the eye. The longer eyeball stretches and thins the tissues, including the sclera, choroid, and retina, making the eye more vulnerable to a range of complications.
1. Myopic Degeneration
Not to be confused with age-related macular degeneration, myopic degeneration is one of the most vision-threatening complications of high myopia. The central part of the retina, the macula, is responsible for sharp, detailed vision. The macula can develop degenerative changes due to progressive stretching and thinning. These include:
Lacquer cracks: breaks or splitting in Bruch's membrane underlying the retina
Choroidal neovascularization (CNV): Abnormal blood vessels that grow under the retina that leak fluid or bleed. This causes retinal hemorrhage and causes your central vision to appear distorted (straight lines appear wavy).
Fuchs spot: A pigmented scar that forms after CNV resolves, leading to central vision loss.
Atrophy: Thinning of retinal tissue and loss of photoreceptors (rods and cones), leading to visual scotoma, or blind spots in the vision.
This image was originally published in the Retina Image Bank. David Callanan, MD. Myopic Degeneration / CNVM. Retina Image Bank. 2014; Image Number 19392. © the American Society of Retina Specialists."
2. Retinal Detachment
High myopia significantly increases the risk of retinal detachment. The elongated eye stretches and thins the peripheral retina, making it more susceptible to:
Lattice degeneration: areas of thin retina with abnormally adherent vitreous gel, increasing the chance of ripping the retina with any vitreous traction
Retinal tears or holes: When untreated, these progress to retinal detachment, a surgical emergency that can cause permanent vision loss if not repaired promptly.
3. Posterior Staphyloma
This is an outpouching or bulging of the back part of the eye, common in highly myopic eyes. It alters the contour of the retina and can contribute to distortion and degeneration in the macula.
4. Vitreoretinal Interface Disorders
High myopia is associated with earlier and abnormal separation of the vitreous (vitreous detachment), which can cause:
Macular holes
Epiretinal membranes
Vitreomacular traction
These conditions can distort vision and often require surgical intervention.
5. Glaucoma and Optic Nerve Changes
People with high myopia may be at increased risk of developing open-angle glaucoma. It's hypothesized that the stretched and thinned sclera (the white part of the eye comprising its outer wall) can alter the structure of the optic nerve head, making it more vulnerable to pressure damage. The exact mechanism is unknown. Additionally, diagnosing glaucoma in highly myopic eyes can be more challenging due to anatomical variations and difficulty assessing the features of the optic nerve.
Treatment Options: How to Prevent High Myopia
Given the potential for vision loss due to retinal complications, there is significant interest in preventing the progression of myopia. Research has given us some effective options, particularly when initiated in childhood.
1. Lifestyle Modifications
Increased Outdoor Time
Spending more time outdoors has been shown to significantly reduce the onset and progression of myopia in children. Natural light may help regulate eye growth and reduce the risk of axial elongation. Approximately 13 hours per week of outdoor time is recommended.
Limit Near Work
Encouraging children to take breaks during reading or screen time (e.g., the 20-20-20 rule: look 20 feet away for 20 seconds every 20 minutes) can help reduce eye strain and potentially slow progression.
2. Pharmacologic Interventions
Low-Dose Atropine Eye Drops
Atropine eye drops have been shown in multiple studies (e.g., ATOM, LAMP) to reduce myopia progression by up to 50% or more, with minimal side effects.
Atropine works by acting on muscarinic receptors, possibly inhibiting axial elongation through non-accommodative mechanisms.
It’s typically used once daily at night and can be continued for several years. The eye drops are usually well-tolerated and do not blur the vision.
3. Optical Interventions
Orthokeratology (Ortho-K)
Special contact lenses worn overnight reshape the cornea temporarily, allowing for clear vision during the day.
Ortho-K also slows myopia progression by flattening the central cornea and reducing the focusing power of the eye.
Overnight use of contact lenses can predispose to a serious infection called a corneal ulcer. Risks and benefits of this treatment should be carefully discussed with your eye doctor. Due to this potentially blinding complication, I personally recommend patients to consider other treatment options first.
Multifocal or Dual-Focus Contact Lenses
These lenses correct distance vision while creating myopic defocus in the peripheral retina (intentionally blurring the peripheral vision).
These are daily disposable contact lenses that are not worn overnight and therefore carry less infection risk than Ortho-K mentioned above.
Several brands (e.g., MiSight) have been FDA-approved for myopia control in children.
Specialized Spectacle Lenses
Lenses such as DIMS (Defocus Incorporated Multiple Segments) and HAL (Highly Aspherical Lenslets) are designed to slow myopia progression through peripheral defocus.
These are well-tolerated and increasingly available.
4. Surgical Interventions for Complications
While not used to prevent high myopia, surgery plays a vital role in managing complications in adults:
Vitrectomy for macular holes, retinal detachment, or vitreomacular traction.
Anti-VEGF injections for CNV.
Scleral reinforcement surgery or macular buckles (still experimental in many countries) may help limit axial elongation in extreme cases.
Living with High Myopia: A Lifelong Journey
For individuals who already have high myopia, the focus shifts to monitoring and protecting vision:
Regular retinal exams with OCT and widefield imaging
Prompt attention to symptoms such as flashes, floaters, or a curtain over vision.
Protection from trauma (high myopes are at greater risk for retinal tears from minor impacts)
Clear communication with eye care professionals about the specific risks associated with their level of myopia
Final Thoughts
High myopia is not just a stronger glasses prescription. It’s a lifelong risk factor for potentially blinding eye diseases. But the good news is that early prevention and regular monitoring can make a difference. With the advent of myopia control therapies and greater awareness, we now have the tools to not only preserve vision but to proactively protect it with early childhood intervention.
If you or a loved one has high myopia, talk to your eye care provider about regular retinal screening and whether myopia control treatments are appropriate. As with many things in medicine, the earlier we act, the better the outcomes.
Dr. Sophia Wong is a retina specialist, surgeon and board-certified ophthalmologist. She established Beacon Retina, the first concierge ophthalmology practice in the Washington, D.C. metro region, to prioritize thoughtful, patient-centered care for preserving long-term vision.
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