Castroviejo Caliper is a multipurpose surgical tool used in many plastic and cosmetic surgeries such as rhinoplasty procedures and ophthalmic procedures. It is an extremely important and useful ophthalmological instrument which facilitates in measuring the distance for dissecting muscles during strabismus surgeries. It is also used to take measurements during ptosis, retinal detachment and pars plana vitrectomy surgery. The Castroviejo Caliper has one straight end and one curved end to accommodate various surgical needs.