A novel pupillometer smartphone application demonstrates accurate results compared with a validated clinical pupillometer: The Pupillary Light Response Validation (PLR-V) Study

The pupillary light response is a sensitive biomarker commonly used for neuromonitoring in intensive care units worldwide. Automated pupillometers have demonstrated increased inter-rater reliability compared with manual assessments by clinicians, allowing for objective repeated assessment. The purpose of this study was directly to compare the raw values and reproducibility of results from a novel automated pupillometer smartphone application, MindMirror, against an existing validated pupillometer, the Neuroptics NPi-200. This study was a prospective cohort study comparing pupillary light response values from three consecutive readings from the MindMirror application and the Neuroptics NPi-200 pupillometer in 66 well subjects. Initial diameter values for NPi-200 and MindMirror did not demonstrate a clinically significant mean error (−0.37 mm ± 0.51 mm) with comparable inter-sample repeatability. Other parameters suggestive of reduced constriction amplitude and velocity, were likely to be related to the clinical conditions of collection. The data suggested that the novel MindMirror smartphone application provided accurate results that were predictable and comparable to the gold standard device for automated pupillometry, and may therefore have utility as a portable accessible device for the rapid assessment of pupillary light response, particularly outside the intensive care unit.