I have a corneal defect, and was tld by a specialist, that i need corneal transplant, but i don't wanna, would i become totally blind if i don't do it?

Probably not: Your vision and/or pain may get worse, but regardless of the condition, you are unlikely to become completely blind. The purpose of a corneal transplant is to improve vision or decrease pain. Seek a second opinion if that will help with your decision regarding a corneal transplant.

Probably not: There are many diseases in which a cornea transplant can be performed to improve the vision. In fact, different parts of the cornea can be transplanted. Although some corneal conditions are progressive, you will likely not become totally blind from them. You should speak to your ophthalmologist to better understand your condition and the prognosis if you don't have a transplant.