June 5, 2017 E-Pearl of the Week: Pharmacologic pupil: The “blown pupil” of a healthy patient
June 5, 2017
Pharmacologic pupil: The “blown pupil” of a healthy patient
Medications are a common benign cause of unilateral mydriasis. In the outpatient setting, finger-to-eye contact involving scopolamine patches, glycopyrrolate cream, or certain plants (e.g. Jimson weed) are frequent causes. Nebulized ipratropium escaping through an ill-fitted mask is common in inpatients with respiratory distress. The use of pilocarpine, a muscarinic agonist, can be helpful in diagnosis. Occupation of muscarinic acetylcholine receptors will prevent constriction of the mydriatic pupil in response to the instillation of 0.1% pilocarpine, which suggests benign rather than dangerous causes (e.g. compressive oculomotor palsy). Often, in patients without other neurologic findings, careful observation may be sufficient to ensure return of pupillary function.
- Moeller J, Maxner C. The Dilated Pupil: An Update. Current neurology and Neuroscience Reports 2007; 7: 417-422.
Submitted by Stephen Aradi, MD - Neurology Resident, University of Pennsylvania.
Dr. Aradi reports no disclosures.
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