Is canthopexy ever a good option & in what instances should it be used?

As far as I can tell, neither a canthoplasty or canthopexy are ever enough on their own to solve scleral show issues. Most surgeons seem to recommend at least canthoplasty with the addition of spacer grafts, sometimes also orbital rim implants. If this is the case, in what instance should canthopexy be used? As it seems canthoplasty is always the procedure that surgeons go for to solve eyelid retraction. Thanks!