(Not a doctor, just read some papers before doing my PRK)
SMILE is new but insanely expensive, though it's the only procedure you can do if you need high correction.
LASIK you flap up the epithelial cells and part of your cornea, and then the laser comes in and ablates the inside of your cornea and you put it back on. If you need high correction, you need more depth of ablation. Since you "lost" some of your cornea because of the flap in terms of depth that can be ablated, for medium to high correction, it is not possible. I think if you have -5 or so it starts getting dicey.
PRK you don't have the flap, they just rub off the epithelial cells so you have the entire cornea to ablate if you want. I think this also starts getting dicey with really high ablation depth, obviously. If you have like -12, the doctor will not even think about PRK.
SMILE you actually pop in a high diffraction, engineered lens in, which can be used to achieve a ludicrously high correction, at the cost of well, cost, and maybe more uncertain long term prognosis?
SMILE is new but insanely expensive, though it's the only procedure you can do if you need high correction.
LASIK you flap up the epithelial cells and part of your cornea, and then the laser comes in and ablates the inside of your cornea and you put it back on. If you need high correction, you need more depth of ablation. Since you "lost" some of your cornea because of the flap in terms of depth that can be ablated, for medium to high correction, it is not possible. I think if you have -5 or so it starts getting dicey.
PRK you don't have the flap, they just rub off the epithelial cells so you have the entire cornea to ablate if you want. I think this also starts getting dicey with really high ablation depth, obviously. If you have like -12, the doctor will not even think about PRK.
SMILE you actually pop in a high diffraction, engineered lens in, which can be used to achieve a ludicrously high correction, at the cost of well, cost, and maybe more uncertain long term prognosis?