Gaze deviation in stroke
Seizures resulting in gaze deviation
Gaze preference is an acute inability to produce gaze contralateral to the side of a cerebral (supranuclear) lesion. Strokes or other destructive lesions involving the frontal eye fields cause a tonic gaze deviation that “looks towards the lesion.” This is because the intact FEF is now working unopposed to drive the eyes towards the non-functional side.
In such cases, the doll’s head maneuver generates a full range of horizontal eye movements because the vestibular-ocular pathways are intact.
Stroke is the most common cause.
The eye movement dysfunction is generally temporary, lasting only days or weeks. Presumably, alternative cerebral-bulbar pathways (perhaps from the parietal lobe) become increasingly capable of generating the saccades and maintaining central gaze.
Deviation of the eyes may occur with seizures involving any cerebral lobe.
Most notably, a lesion of the FEF that causes excess neural activity, such as a focal seizure, will drive the eyes contralaterally during the period of the seizure. The head may also turn contralateral tin the same direction as the eyes. In the postictal state, when there may be lingering hypoactivity of the FEF neurons, the eyes may deviate ipsilateral to the side of the lesion because of a relative increase in input from the unaffected FEF on the opposite side of the brain.
Transient and conjugate downward or upward ocular deviation may occur in healthy newborns. In these cases, the vertical doll’s head maneuver can move the eyes out of their tonically held position. Tonic downgaze in premature newborns, however, may be associated with serious neurologic disease, especially when intraventricular hemorrhage expands the third ventricle and presses on the pretectum. Tonic downward deviation of the eyes combined with retraction of the eyelids, referred to as the setting sun sign, is primarily observed in children as part of dorsal midbrain syndrome. Conjugate paresis of upgaze is an associated ɹnding, and in these cases, the doll’s head maneuver cannot induce upward movements of the eyes.
Oculogyric crisis is a tonic upward ocular deviation, sometimes directed toward the right or left. Patients find it diɽcult to direct their eyes downward. This disorder often arises from neuroleptic antipsychotic drugs as well as antiemetic drugs such as metoclopramide, due to dopamine receptor blockage. These drugs alter supranuclear input onto the ocular motor nuclei. The crisis may persist for hours.
Patients with Wilson disease may have an oculogyric crisis.
Administration of anticholinergic drugs (eg, prochlorperazine) promptly stops the crisis.
Wrong way eyes refers to the phenomenon of ocular deviation away from the lesion, contrary to the usual pattern.
This is typically associated with large intracranial hemorrhages or extensive hemispheric infarction. Thalamic involvement appears to be common.
The prognosis of patients with wrong-way deviation is generally poor; most patients with this sign died.
Pathophysiology: The precise mechanism is unclear, but damage to the adjacent rostral brainstem where oculomotor pathways cross over from the contralateral hemisphere is the accepted explanation.