BGN Eye Clinic – Jamsil Main Branch

Suspect High Myopia?
Symptoms to Correction Methods — A Complete Guide

If your vision is blurry and your eyes feel constantly strained, high myopia may be the cause. Here is an overview of the key symptoms, correction options, and the criteria to consider when choosing a surgical method.

What Is High Myopia? Definition & Characteristics

Myopia is a refractive error in which distant objects appear blurry, and its severity is measured in diopters (D). A prescription of -9D or higher (sometimes defined as -10D or higher) is generally classified as "high myopia." It is considered a stage beyond simply having poor vision — one that can affect the structural integrity of the eye itself.

Ordinary myopia can be corrected to a reasonable degree with glasses or contact lenses. However, high myopia is often accompanied by an excessively elongated axial length (the length of the eyeball), which increases the risk of thinning of the retina and the development of complications.

Difference from Ordinary Myopia
Ordinary myopia (roughly -3D to -6D) can be easily corrected with glasses or contacts. High myopia, however, frequently involves structural changes to the eye, which means precise diagnostic testing is absolutely essential when selecting a surgical approach.

Symptoms of High Myopia

High myopia can be accompanied by a range of eye symptoms beyond simple vision loss. If any of the following symptoms persist, it is strongly recommended that you undergo a comprehensive eye examination.

• Severe Vision Deterioration — Even with glasses or contacts, corrected vision may be insufficient, and night vision in particular may be notably poor.
• Floaters (Myodesopsia) — Spots or thread-like shapes that appear to drift across the visual field. In high myopia, floaters may appear at an earlier age and more frequently.
• Photopsia (Light Flashes) — The perception of flashing lights even in the absence of an actual light source. This may be caused by vitreous traction on the retina and warrants careful attention.
• Visual Field Obstruction — If part of your visual field appears blocked or covered by a dark curtain, this may be a sign of a retinal abnormality and requires immediate examination.
• Increased Eye Fatigue — Eyes tire quickly after near-distance tasks such as reading or using a smartphone, often accompanied by headaches.
• Increased Risk of Complications — If left unaddressed, high myopia can progress to serious complications including retinal detachment, glaucoma, and macular degeneration. Regular eye check-ups are essential.

Correction Methods for High Myopia

Surgical correction for high myopia varies depending on the individual's eye condition. The most appropriate method — SMILE, ICL (Implantable Collamer Lens), or LASEK — is selected after a comprehensive evaluation of factors including corneal thickness, ocular structure, and lifestyle.

SMILE

SMILE uses a laser to precisely reshape the interior of the cornea through a small incision. It is characterized by a fast recovery time and a low risk of dry eye due to the minimal incision involved.

For very high myopia (-10D or above), there may be limitations to the correctable range; generally, correction of approximately -8D is possible. However, it is only applicable when sufficient corneal thickness can be confirmed, so a thorough examination and detailed consultation with your physician are necessary.

ICL (Implantable Collamer Lens)

ICL surgery involves implanting a specialized lens inside the eye without removing any corneal tissue. It is a valuable alternative for patients whose corneas are too thin or whose myopia is too high for LASIK or LASEK.

Even in cases of high myopia, ICL covers a wide correctable range, making it an option for many patients. Another key advantage is that the lens can be removed if needed. However, there must be sufficient space inside the eye (anterior chamber depth) for the procedure to be performed safely.

LASEK

LASEK involves reshaping the surface of the cornea and does not create a corneal flap, which reduces the risk associated with external impact.

It may be selected for high myopia patients who lack sufficient corneal thickness for other procedures but still meet the criteria for LASEK. However, the initial recovery period is longer — approximately 1 to 3 months — and may involve some discomfort during healing. Strict post-operative care, including UV protection, is required.

Comparison of Surgical Methods at a Glance

The table below summarizes the key differences between the three surgical options. Rather than declaring one method superior, it is important to understand that the optimal approach depends entirely on each individual's eye condition.

Criteria to Consider When Choosing a Procedure

Corrective surgery for high myopia is not determined by prescription numbers alone. The safest and most effective method is chosen through a comprehensive assessment of the individual's corneal condition, ocular structure, and lifestyle.

• Corneal Thickness & Shape — If the cornea is thin or irregularly shaped, LASIK or SMILE may not be appropriate. A corneal thickness measurement should be performed first to determine a safe ablation range.
• Ocular Structure (Anterior Chamber Depth, etc.) — ICL requires sufficient space within the eye for safe implantation. Whether the procedure is feasible is determined by precise test results, including anterior chamber depth and corneal endothelial cell count.
• Lifestyle & Occupational Environment — Those with high physical activity levels or frequent physical contact may benefit more from procedures that do not create a corneal flap. Recovery time and its impact on work or study schedules should also be factored in.
• Comparative Consultation: LASEK vs. Other Methods — No single method is universally superior. The right surgery can differ between two patients with identical prescriptions. It is strongly recommended to make the final decision only after reviewing your full diagnostic results with your physician.

High myopia extends beyond a simple vision problem — it is associated with a range of potential complications involving the retina, glaucoma, and more. At BGN Eye Clinic – Jamsil Main Branch, we conduct precise diagnostic evaluations to accurately assess each patient's individual eye condition and help identify the safest corrective approach together. If you are concerned about any symptoms, we encourage you to consult a specialist today.