There are some complications you may suffer if something goes wrong during lasik surgery. In some cases, you may suffer double vision after the surgery. But it will fade soon later. However, some people may experience permanent double vision though it is really rare. Moreover, some surgeons who are not experienced enough don't know your cornea is too thin to have lasik surgery, but they still give you the surgery, you may suffer complete vision loss or blindness.
Before you have lasik surgery, you will undergo a rigorous preoperative examination, in order to check on whether you are appropriate to have this surgery. If you pass the checking, in general, you will not go blind after the surgery. Most patients will not get myopia again after the surgery, only some individual pathologic myopia with a degree exceed 1400 may produce part of rollback, but the rollback rate will not be great.