What are the treatment options to correct short-sightedness of more than 1000 degrees?

High myopia can indeed be quite a burden when unaided vision is very poor, which results in heavy reliance on visual aid. This can limit some activities.

To safely improve your unaided vision, there are several options:

1) LASIK

It is still possible to consider LASIK, provided your cornea measurements allow it.

Although the results of treatment for LASIK for high myopia may not be as satisfactory as for low myopia due to:

• higher chance of dry eyes,
• possible induced higher order aberrations and
• higher chance of post-LASIK regression

A significant number of high myopia sufferers are still able to obtain good results.

I often recommend adding cross-linking (LASIK-EXTRA) to such cases to reduce the chance of regression (myopia returning) as these cases are less likely to be eligible for further enhancement via LASIK.

2) Implantable contact lens (ICL)

The phakic intraocular lens (which means lens implantation without removing your natural lens) by Staar Visian ICL, made of biocompatible materia works well for correction of high power of myopia +/- astigmatism.

Again, certain criteria in eye measurements need to be met for safety. As the cornea is practically intact (bar a small sub 3mm incision through which the lens is implanted), there is minimal side effects like dry eyes.

The current ICL has a tiny hole or port in the center of the lens to improve fluid flow within the eye, and in my experience is far safer for the eye compared to previous generation of the ICL. However, beyond close to 1800 myopia or less when there is also astigmatism, ICL alone is not sufficient.

3) Bioptics

This is a term describing combining a lens implant technique with LASIK or its alternatives like SMILE or surface ablation.

For above 1800 myopia the only possibility is combining the ICL treatment with additional laser correction. This comes with the combined pros and cons of both ICL and LASIK procedures.

You must have found out that SMILE currently only treats up to 1000 deg of myopia. It is being used experimentally to treat higher than 1000 deg myopia, but is not commercially released for this yet.

Also a gentle reminder that high myopia comes with slightly higher risk of other eye problems like glaucoma, cataract and retina tears, hence do take a long term view as well in looking after your eyes.

I wish you all the best in finding a solution to your high refractive error. Cheerio!

Hi Lydia

The surgical treatment options for people with very high myopia may still include laser techniques like LASIK, as well as Implantable Collamer Lens (ICL) surgery.

LASIK can be considered if the cornea happens to be thicker than average, say for example, above 600 microns in central thickness. Practically speaking, the upper limit at which LASIK can still give satisfactory visual quality is around -10 to -11D (1000 to 1100 degrees) or so, although I know of rare cases which had even higher myopia than this corrected with LASIK.

The main issue with regard to LASIK for such high powers is a higher risk of compromised visual quality. This goes with the smaller optical zone that needs to be used (to avoid thinning the cornea excessively), with the smaller zone increasing the risk of night time halos and poorer vision in the dark, as well as a somewhat higher risk of regression (getting shortsighted power again).

ICL surgery avoids most of these issues with visual quality. A mild thin halo may be noticed in the dark with ICL, but usually patients are not disturbed by this and after a while, stop noticing it.

Of course, LASIK and ICL are 2 very different procedures each with their own pros and cons. I would almost never do ICL for a low myope (unless the cornea appeared weak), while on the other hand I almost always prefer to do ICL for patients with very high spectacle power-whether that is myopia, hyperopia or astigmatism, if possible. ICL is intraocular surgery and carries a very small risk of things like cataracts, although since it is reversible, it can be removed if problems are seen so that they do not get worse. On the other hand, while there is no risk of LASIK causing a cataract, the visual quality issues can be a bit too much of a con for those with very high spectacle powers.

One thing I think you should also note is that as a wearer of RGP lenses, you are used to very crisp, clear vision. That is the great strength of RGP lenses, and very few (if any) methods can give comparable visual quality. If absolute sharpness of vision is your ultimate goal, I think you should stick to your RGP lenses. If you are unable to wear them, or prefer not to for various reasons, and prioritise convenience over absolute sharpness, then ICL surgery would probably be the method of choice (provided your eyes meet eligibility criteria).

Myopia in excess of 1000 degrees puts you in the category of few patients who may not be suitable for conventional femto-laser assisted surgery.

There are other options for yourself to be spectacle-free.

These include:

a. Implantable collamer lens. This reversible procedure to implant a collamer lens to correct your refractive error is a good option if you are suitable for it. It carries the risks of an intra-ocular procedure, and post-surgery you will need to be reviewed regularly in the immediate post-operative period for complications of raised eye-pressure, prolonged inflammation or infection, or cataract development.

b. Alternatively - some patients may be suitable for a surface ablation technique including Epilasik with anti-scarring medication (Mitomycin-C) and cornea-strengthening procedure (riboflavin-assisted cross-linking), or Epilasik-plus.

Do speak to your ophthalmologist for a detailed discussion about your options, after you have had a comprehensive ocular examination. Best of luck in your decision!

ESG

I am glad to inform you that having 1,000 degrees of short-sightedness does not automatically mean that you are not eligible for laser vision correction (LVC) procedures like LASIK and ReLEx SMILE. What is important to ascertain are the thickness and shape of your corneas, and the overall health of your eyes. I would encourage you to still go for an evaluation to determine your suitability for laser refractive surgery.

Should it be found that you are not suitable for LVC, the alternative technique could be the insertion of an implantable collamar lens (ICL). This technique works best in cases where the refractive errors are in the higher ranges and where the patient may not be suitable for LVC. It works very much like a contact lens but rather than sitting on your cornea, the ICL sits in the space between your iris and natural lens.

The main adavtanges of ICL over LVC are that it corrects far higher levels of refractive errors, it is potentially reversible by way of its removal and there is less potential for complications relating to dry eye or corneal weakening (as in the case of LASIK). The potential downsides of ICL are its significantly higher cost and potential complications relating to earlier development of cataracts or glaucoma.

All our patients are tested for suitability for both ICL as well as LVC. That way, we are then best able to customise the treatment option to the individual patient.

I wish you every success in your efforts to become spectacles independent.

Dr David Chan