What is a surgeon's obligation to obtain the consent of a patient?

In Hopp v. Lepp, 1980 CanLII 14 (SCC), [1980] 2 S.C.R. 192, the court considered the issue of informed consent. Laskin C.J. offered the following summary of a surgeon’s obligation: In summary, the decided cases appear to indicate that, in obtaining the consent of a patient for the performance upon him of a surgical operation, that surgeon, generally, should answer any specific questions posed by the patient as to the risks involved and should, without being questioned, disclose to him the nature of the proposed operation, its gravity, any material risks and any special or unusual risks attendant upon the performance of the operation. However, having said that, it should be added that the scope of the duty of disclosure and whether or not it has been breached are matters that must be decided in relation to the circumstances of each particular case.