It can be challenging to complete a full neurologic assessment
of the comatose patient. However, you can evaluate brainstem function and specific cranial nerves
(III, IV, VI, VIII) by testing for the oculocephalic reflex, also known as doll’s eyes reflex.
How to Assess for Doll’s Eyes Reflex (Bickley et al., 2021)
Before you attempt to assess for the oculocephalic reflex, ensure the patient has a stable cervical spine without c-spine precautions or neck injuries. Then, holding the patient’s upper eyelids open, turn the patient’s head quickly, from one side and then to the other. If the comatose patient’s brainstem is intact, when the head is turned in one direction, the eyes move to the opposite side, like a doll’s eyes. If the eyes continue to look straight (stay midline) without movement relative to the head position, this is negative for doll’s eye movements and may indicate a lesion of the midbrain or pons. This reflex is suppressed in a conscious adult with normal neurologic function but is active in a comatose patient patient with brainstem function. The test can be performed in both the vertical and horizonal directions.
Clinical Significance (Dishioni & Tadi, 2022)
A doll’s eyes reflex can be a used in clinical practice in the following areas:
- Lesions in the vestibular nerve or nuclei have been shown to impair the ipsilateral doll’s eye reflex.
- Dizziness can be assessed using the doll’s eye reflex in the office setting.
- Vertical and horizonal abnormal eye movements may be seen in schizophrenic and bipolar patients. However, these patients should show an intact doll’s eye reflex.
- A positive doll’s eyes reflex in critically ill intensive care patients may predict a change in mental status (i.e., delirium, coma, confusion) once sedation is discontinued.
- Neonates do not suppress the doll’s eyes reflex prior to 11.5 weeks of age; the reflex can be used as a neurologic developmental milestone.
- Do not perform the doll’s eye test in patients with cervical spine or neck injury.
- A positive doll’s eye reflex (eyes move in opposite direction of head movement) indicates an intact brainstem.
- A negative doll’s eye reflex (eyes remain midline or move in same direction of head movement) indicates severe brain stem dysfunction.
- These results only apply to patients who are comotose. These reflexes are suppressed in the conscious adult with normal neurologic function.
Bickley, L. S., Szilagyi, P. G., Hoffman, R. M., & Soriano, R. P. (2021). Bate’s Guide to Physical Examination and History Taking (13th ed.). Wolters Kluwer Health: Philadelphia.
Dishion, E. & Tadi, P. (2022, May 8). Doll’s Eyes. StatPearls [Internet].