For patients with a large degree of myopia, undergoing cataract surgery can be life changing because in addition to fixing the cataract, we can also address huge amounts of myopia. But be careful, because I am convinced that you should not aim for plano in patients with ultra-high myopia.
The video presented below shows cataract surgery in a highly myopic patient and my rationale for choosing a significantly myopic refractive outcome. This patient has always been very myopic and today is more than -30 diopters of myopia. He is functionally monocular and his only seeing eye now has a very significant cataract. He was likely quite myopic in very early childhood and as a result he developed bilateral ametropic amblyopia. Previously his best corrected vision with hard contact lenses was 20/80.
He currently spends most of his day using his mobile phone, tablet, and laptop. And he has under-corrected his contact lenses so that he remains about -6 diopters myopic. This gives a near point of about 16 centimeters, which he finds very useful for his daily life. It is important to understand that he does not want to be plano or even -1.00 in the post-op period. In addition, the variability of lens power estimation plus the difference with lens geometry, tend to make the prediction of the post-op refractive state less accurate.
For ultra-myopic patients, do not aim for a plano post-operative outcome. Going from -36 to -6 diopter is amazing for this patient. Even going from -20 to -2 diopters is great and will make patients very happy. But going from -12 to +1 diopters will be difficult for the patient to tolerate.
If you are aiming for plano with traditional IOL power calculations, you will almost certainly end up hyperopic. If you use the newest methods for lens power calculations and aim for plano and achieve plano, you may have a reasonably happy patient but you may also have an unhappy patient. If you use the newest methods of IOL calculations and then also aim for mild post-operative myopia, then you will have a very happy patient. And if you absolutely must, then it is easy to perform an excimer laser corneal ablation (LASIK or PRK) to treat the residual mild myopia quite accurately.
We have already discussed the specific methods of lens power estimation and surgical techniques for these highly myopic patients in the following articles:
- surgical technique for high myopia cataract surgery
- IOL power calculation in high myopia
- IOL power quiz for high myopia
Please review the above articles before proceeding with the video below (click to play):