Gaze Palsy vs. Gaze Preference: Key Clinical Distinctions

Gaze Palsy: Structural Inability to Move Eyes

Gaze palsy represents an inability to move the eyes in a specific direction due to neurological damage, whereas gaze preference describes eyes that rest in a deviated position but retain the ability to move past midline with appropriate stimulation, such as the vestibulo-ocular reflex, as noted by the American College of Emergency Physicians 1
Partial gaze palsy is characterized by eyes that can move partially in the affected direction but movement is incomplete, scoring 1 on the NIH Stroke Scale, according to the American College of Emergency Physicians 1
Complete gaze palsy is marked by forced eye deviation or total paresis that cannot be overcome by Doll's eyes, with a score of 2 on the NIH Stroke Scale, as defined by the American College of Emergency Physicians 1
The critical distinguishing feature of gaze palsy is that even with vestibulo-ocular reflex testing, the eyes cannot move past midline in the affected direction, as stated by the American College of Emergency Physicians 1

Vertical gaze palsy is characteristic of progressive supranuclear palsy, particularly affecting downward gaze more than upward, often with absent optokinetic nystagmus or slowed downward saccades, as reported in the medical literature 2
Sixth nerve palsy produces horizontal gaze limitation but is an infranuclear problem, not a supranuclear gaze palsy, according to the American Academy of Ophthalmology 3

Gaze preference describes a resting deviation of the eyes that can be moved past midline with appropriate stimulation, such as the vestibulo-ocular reflex, as noted by the American College of Emergency Physicians 1
The vestibulo-ocular reflex successfully brings the eyes across midline, proving the motor pathways are intact, as stated by the American College of Emergency Physicians 1
Gaze preference typically indicates a cortical or subcortical lesion affecting the frontal eye fields or their descending pathways, rather than brainstem gaze centers, as reported in the Journal of Neurosurgery 4

In acute stroke, gaze preference toward the side of a hemispheric lesion is common, representing disruption of cortical control over eye movements, not structural inability to move the eyes, as noted in the Journal of Neurosurgery 4

The vestibulo-ocular reflex is the definitive test to distinguish between gaze palsy and gaze preference, with gaze preference allowing eyes to cross midline with head turning, and gaze palsy resulting in eyes that remain fixed and cannot cross midline despite head turning, as stated by the American College of Emergency Physicians 1

The American Academy of Neurology suggests that progressive supranuclear palsy (PSP) is a common cause of chronic vertical supranuclear gaze palsy, usually caused by FTLD-PSP (frontotemporal lobar degeneration with tau pathology), characterized by postural instability with supranuclear gaze palsy, accompanied by varying degrees of cognitive, behavioral, or other movement symptoms 5, 6, 7
Corticobasal degeneration (CBD) and Lewy body disease can also cause PSP syndrome, although less commonly 5, 6, 7

The American College of Radiology recommends considering cranial nerve III (oculomotor) nucleus lesions, which can be caused by vascular compression (e.g., aneurysm) or vasculopathic etiologies (e.g., diabetes, hypertension), and can result in pupil-involving or pupil-sparing palsies 8
Cranial nerve IV (trochlear) nucleus lesions are most often caused by trauma, and rarely by nerve sheath tumors 8
Cranial nerve VI (abducens) nucleus lesions may be caused by lesions within the prepontine cistern, skull base, cavernous sinus, or sella, and can occur with increased intracranial pressure without direct nerve compression 8

The American Academy of Ophthalmology suggests performing forced duction and forced generation testing to distinguish restriction from paresis of extraocular muscles 9
Cover testing should be performed at near and distance in primary and secondary gaze positions, and evaluate torsion for patients with vertical misalignment 10
A detailed sensorimotor exam with attention to versions, ductions, saccades, pursuit, vergence, and near reflex is essential for diagnosing nuclear gaze palsy 9

The American College of Radiology recommends MRI of the head without and with contrast, including small field-of-view high-resolution T2-weighted images of cranial nerves, for suspected nuclear pathology 8
CTA or MRA is indicated when vascular compression from aneurysm is suspected, and CT is preferred over MRI if concern for ferrous-metallic foreign body or orbital fracture 8, 9
High-resolution orbital imaging is useful for evaluation of mechanical causes 10