What's the best LASIK procedure to correct night vision?

Hi Moi

This is a great question. As a military personnel, you should definitely consult your commanding officer and service Ophthalmologist about your vocation suitability to have a refractive surgical procedure performed. There are several military vocations that you would be disqualified from after having refractive surgery.

In general, if you wanted to consider a surgical procedure to improve your night vision with the least likely to induce higher order aberrations or impair your performance at night, then the short answer would be that you should consider the implantable collamer lens first.

If you are not suitable for an ICL, then the laser procedures to consider in order would be SMILE, then femto-assisted Lasik.

For the most precise and tailored answer for you, I would suggest that you undergo a comprehensive evaluation at your refractive centre of choice so that all your options appropriate for your eye can be discussed, and all your concerns can be adequately addressed. Best of luck!

ESG

To answer your question, first we need to figure out what is wrong with your night vision.

Some people get a phenomenon called night myopia when their myopia degree seem to increase at night, partly due to a combination of increased accommodation tone through the day, and also due to pupil dilation in the dark which will cause an increase in higher order aberration.

There are also rare cases whose colour vision is problematic due to inherited eye disease, and these cases may manifest with poorer night vision. Some may simply have dry eyes that worsen through the day after long hours staring at the computer screen, culminating in deterioration in their quality of vision at night. There may even be early lens changes (cataract) that could cause a deterioration of night vision.

For my patients with a complaint like yours, I would usually make sure that I examine

1) their pupil size in the dark

2) the wavefront scans of their (a)cornea and (b) whole eye

3) A careful full eye check including colour vision, sometimes also the visual field.

A full refraction (including with relaxing eyedrops), detailed examination for dry eyes and of the lens and retina are my routine for all cases anyway.

So if the higher order / wavefront aberrations are higher than usual, I often would offer wavefront-guided LASIK or LASEK treatment (either cornea or total, depending on the age of the patient). SMILE does not treat higher order aberrations and is unlikely to incorporate wavefront-guided treatment in the foreseeable future, although in comparison, it tends not to induce wavefront aberrations compared to standard LASIK.

The current iteration of SMILE for correcting astigmatism is also not machine-guided, hence surgeon factor is important for correction of higher degrees of astigmatism.

The current ICL model (Staar Visian Evo) is significantly safer than previous models, as it now has a tiny hole right in the center to reduce possible complications. However, some patients notice a bit of night halos from this, although so far, none of my ICL patients found the halos problematic after a few weeks.

The choice between wavefront LASIK (surface ablation i.e. LASEK / epiLASIK/ PRK not recommended for high power like yours) vs ICL in your scenario will again depend on several factors. If your cornea thickness is irregular or insufficient to support safe wavefront-guided LASIK eyes (wavefront-guided treatment sacrifices more cornea tissue than standard LASIK), or if you suffer from dry eyes, ICL will be the choice treatment. However, there are also criteria for ICL such as the depth of your front of eye, the size of your cornea etc which you need to fulfill.

Hope you find a good solution for treatment of your refractive error. Best wishes!

Dr Daphne Han

Hi Moi

I think the more accurate way of looking at it is to ask about a procedure to reduce (or 'correct') your spectacle power, rather than to correct night vision.

The primary aim of all refractive procedures, whether LASIK, epiLASIK, SMILE or ICL surgery is to reduce spectacle power. They are not designed/meant to correct night vision.

In your case, with high shortsightedness (myopia) and astigmatism, it may be that ICL surgery can give you a good result while affecting night vision less than LASIK.

Generally speaking, the higher the power that is treated with a laser procedure (whether LASIK, epiLASIK or SMILE), the higher the risk that after surgery there are some visual issues at night. These can include some amount of halos, and overall shortsighted feeling if the optical zone treated by the laser needs to be smaller to minimise cornea tissue removal.

As ICL surgery implants a lens of a fixed optical zone into the eye, these issues are minimized. It is still possible to see a thin ring of light or some reflections from the ICL implant, however, these are likely to be much less compared with laser procedures for very high spectacle powers.

Actual suitability for the various kinds of surgery can only be determined after you have a full check up in the clinic, with testing for spectacle power, corneal thickness and anterior chamber depth being particularly important.

To sum up, no refractive procedure corrects night vision. In fact, they may degrade night vision to some extent, the risk increasing somewhat the higher the power that is being treated. Bearing in mind the different options, it is likely that ICL surgery degrades night vision the least for very high spectacle powers. For lower spectacle powers, laser refractive surgery will remain the procedure of choice for most suitable patients.

The choice of either LASIK or Implantable Collamer Lens( ICL) really boils down to answering the key questions of whether your corneas are thick enough for LASIK to be performed safely or if there is sufficient intra-ocular space to accommodate an ICL.

To be clear, both treatments can result in patients seeing haloes and glare at night though the risk may be relatively lower in ICL compared to LASIK when dealing with higher degrees of refractive error.

With regards to improving your night vision, both procedures have the potential to help you in that respect. What is important though is for your surgeon to perform a thorough eye assessment to exclude important eye conditions such as glaucoma, cataracts and retinal detachment that are known to be associated with highly myopic eyes and that may in themselves cause poor vision in low light.

Dr David Chan