II. Indications

  1. Brainstem function testing in coma

III. Mechanism

  1. Afferent limb: Touch stimulates the V1 branch of the Trigeminal Nerve (Cranial Nerve 5)
  2. Reflex center: Pons in the Brainstem
  3. Efferent limb: Temporal and zygomatic arches of the Facial Nerve (Cranial Nerve 7) close the Eyelids

IV. Technique

  1. Touch Cornea, lid or Conjunctiva with cotton whisp
  2. Alternative: Instill 5-10 cc Normal Saline by syringe over the surface of the Cornea

V. Interpretation: Expected response (normal)

  1. Results in a rapid, Blink Reflex in the exposed eye as well as the other eye (consensual response)
  2. Diminished reflex in those who use Contact Lenses
  3. Intact reflex suggests intact Brainstem function

VII. References

  1. Degowin (1987) Diagnostic Examination, 5th ed, MacMillan Publishing Company, p. 810

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