Use of pupil size and reaction to detect orbital trauma during and after surgery.

We describe how pupillary reactions, used as an index of optic nerve function, can be elicited using only one working pupil. This is to challenge the conclusion of a study that did not appreciate this physiological phenomenon and thus gave rise to erroneous conclusions that might otherwise limit the scope of pupil measurements during and after surgery. For suitable cases, non-opioid anaesthesia and further clinical development of pupillometry are suggested by us as measures to monitor optic nerve function.