Neurocritical Care

, Volume 21, Issue 2, pp 309–311 | Cite as

Neurologist Versus Machine: Is the Pupillometer Better than the Naked Eye in Detecting Pupillary Reactivity

  • Christopher L. KramerEmail author
  • Alejandro A. Rabinstein
  • Eelco F. M. Wijdicks
  • Sara E. Hocker
Practical Pearl



A 62-year-old man with severe traumatic brain injury developed postsurgical anisocoria in which there was a discrepancy between pupillometer and manual testing.


Case report.


The patient’s larger pupil was read as unreactive by the pupillometer but constricted 1 mm over 7–9 s of continuous light stimulation.


While pupillometry assessment is a valuable adjunct to the manual pupillary assessment, this case demonstrates that nonreactive pupils read on the pupillometer should be confirmed with the manual examination because it can miss very slowly reacting pupils.


Pupillometer Neurological examination Brain death Uncal herniation Neurocritical care Pupillary reactivity 


Conflict of interest

Christopher Kramer, Sara Hocker, Alejandro Rabinstein, and Eelco Wijdicks declare that they have no conflict of interest.

Supplementary material

Video: Pupillary reactivity assessment using the pupillometer and with manual testing. No reactivity is noted with pupillometer testing, however, slow reactivity was seen with a sustained light stimulus upon manual testing. Video specifications: Author: Christopher Kramer, M.D. Videographer: Elaine Flom, Sally Podein. Length: 23 s. Size: 43.3 MB (MP4 44364 kb)


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Christopher L. Kramer
    • 1
    Email author
  • Alejandro A. Rabinstein
    • 1
  • Eelco F. M. Wijdicks
    • 1
  • Sara E. Hocker
    • 1
  1. 1.Department of NeurologyMayo ClinicRochesterUSA

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