OCULOCEPHALIC REFLEX
the patient’s eyes are held open. the head is briskly turned from side to side with the head held briefly at the end of each turn. a positive response occurs when the eyes rotate to the opposite side to the direction of head rotation, thus indicating that the brainstem (CN3,6,8) is intact.
What is a negative dolls eye reflex?
Typically the doll’s eyes reflex is elicited by turning the head of the unconscious patient while observing the eyes. The eyes will normally move as if the patient is fixating on a stationary object. If there is a negative doll’s eyes reflex then the eyes remain stationary with respect to the head.
What is a normal Oculovestibular reflex?
Vestibulo–ocular reflex is an involuntary reflex that stabilizes the visual field and retinal image during head motion by producing eye movements in a counter direction.
What is the doll’s eye maneuver?
Definition. The doll’s eye maneuver is executed by quickly turning the patient’s head horizontally from side to side or vertically up and down while holding the eyelids open.
What is doll’s eye phenomenon?
doll’s eye phenomenon (reflex)
[dolz i] the movement of the eyes as a unit in the opposite direction when the head is moved; it occurs in an individual with a depressed level of consciousness when cranial nerves three and six are intact. Called also oculocephalic reflex.
What does the blinking reflex involve?
The corneal reflex, also known as the blink reflex or eyelid reflex, is an involuntary blinking of the eyelids elicited by stimulation of the cornea (such as by touching or by a foreign body), though could result from any peripheral stimulus.
How is the corneal reflex tested?
The corneal reflex is tested by closure of the eyelids in response to irritation of the cornea by touching with a sterile cotton applicator. It involves afferent impulses transmitted by the trigeminal nerve and efferent motor impulses via the facial nerve.
What is a Disconjugate gaze?
Definition. Dysconjugate gaze is a failure of the eyes to turn together in the same direction.
What is the Vestibulocollic reflex?
The Vestibulocollic Reflex (VCR) The vestibulocollic reflex acts on the neck musculature in order to stabilize the head. Reflex head movement counters the movement sensed by the otoliths or semicircular canals. The neural pathways mediating this reflex are as yet uncertain.
What causes abnormal VOR?
VOR refers to the “ear to eye” link. VOR dysfunction is caused by the following: Multiple sclerosis. Brain stem ischemia.
What is optokinetic eye movement?
The optokinetic response (OKR) is a reflexive eye movement induced by motion of a wide visual field (Collewijn, 1991). When observers are exposed to sustained visual motion, an alternating pattern of slow and fast eye movements emerges (slow and quick phases), called optokinetic nystagmus (OKN).
Which nerves are involved in the corneal reflex?
The corneal blink reflex is caused by a loop between the trigeminal sensory nerves and the facial motor (VII) nerve innervation of the orbicularis oculi muscles.
