In Leone v. United Health Servs. (282 AD2d 860) a plaintiff opposed the defendant surgeon's motion for summary judgment by relying solely upon the res ipsa loquitur doctrine to sustain his cause of action. The defendant had performed a vasectomy upon plaintiff. It was eventually discovered that the left genitofemoral nerve had been injured. The court held that expert testimony was required to establish that the injury would not have occurred in the absence of negligence. No such expert opinion was produced and, consequently, the complaint was dismissed.