SURGICAL lesions of the facial nerve may arise in immediate conjunction with an operation, or they may be delayed in onset. They may be due to direct injury of the nerve, or they may arise from vascular disorders within the facial canal. I prefer to regard any facial palsy which follows an operation as an immediate one unless there is undisputed proof that it is of delayed onset. Surgeons do not like to think that they have injured the nerve, and many patients referred to me for operations have had palsies described as delayed in onset, but the continuity of the nerve was completely interrupted. You are confronted with a case of complete facial palsy which to the best of your judgment has arisen in immediate conjunction with an operation. Is it a case in which only the myelin sheaths may be involved, a so-called neuropraxia? The patient will in