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Book

Ciliospinal Reflex

Koushik Tripathy  1 , Sriram Simakurthy  2 , Arif Jan  3
In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan.
.
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Book

Ciliospinal Reflex

Koushik Tripathy et al.
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Excerpt

Ciliospinal reflex is characterized by rapid dilation of the ipsilateral pupil (by 1 to 2mm) with a painful or startling stimulus. It is elicited by scratching or pinching over the skin at the side of the neck, upper trunk, and face. This reflex, which was first described by Budge, is present in normal awake or sleeping humans as well as in comatose patients.

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Conflict of interest statement

Disclosure: Koushik Tripathy declares no relevant financial relationships with ineligible companies.

Disclosure: Sriram Simakurthy declares no relevant financial relationships with ineligible companies.

Disclosure: Arif Jan declares no relevant financial relationships with ineligible companies.

References

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    1. Reeves AG, Posner JB. The ciliospinal response in man. Neurology. 1969 Dec;19(12):1145-52. - PubMed
    1. Andrefsky JC, Frank JI, Chyatte D. The ciliospinal reflex in pentobarbital coma. J Neurosurg. 1999 Apr;90(4):644-6. - PubMed
    1. Yang LL, Niemann CU, Larson MD. Mechanism of pupillary reflex dilation in awake volunteers and in organ donors. Anesthesiology. 2003 Dec;99(6):1281-6. - PubMed
    1. Chapman CR, Oka S, Bradshaw DH, Jacobson RC, Donaldson GW. Phasic pupil dilation response to noxious stimulation in normal volunteers: relationship to brain evoked potentials and pain report. Psychophysiology. 1999 Jan;36(1):44-52. - PubMed

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