Is a canthoplasty required when doing lower eyelid retraction surgery?

My eyes changed for the worse after a lower eyelid retraction surgery. I only requested this surgery but come to find out a canthoplasty was also performed which made my eyes look extremely weird especially on the corners and the surgeon is saying that it was required in order to do the lower eyelid retraction surgery. Is it true that a canthoplasty surgery is required when doing a lower eyelid retraction? The canthoplasty ruined my eye appearance and i didnt ask for that surgery. Please respond