Assessment of pupillary function and reactivity is a fundamental component of neurological examination in most intensive care settings.
The conventional eye pen torch method is subjective with a high degree of inter-rater variability. The Pupillometer (NeurOptics) is a novel hand-held infrared device which provides objective measurements of pupillary status; it measures size and constriction velocity (Neurological Pupillary Index - NPi); this may allow a more meaningful interpretation of pupillary response. A previous small study suggested that decreasing NPi is related to future neurological deterioration as measured by invasive intracranial pressure (ICP). Initial pilot data suggests that Pupillometry is superior to pen-torch in accuracy, reliability and objectivity. It can demonstrate pupillary response when the pen-torch cannot. Monitoring NPi trends over time provides extra information and a potential added time window for targeted management. The correlation of NPi with ICP is the subject of ongoing study. The Pupillometer is a novel device that is easy to use and provides accurate, reproducible and clinically useful data. We are continuing this study on a larger scale to see if Pupillometry data can predict dynamic ICP changes and could possibly provide a non-invasive means to monitor ICP.