Module 5: Ocular Motility & Disorders Flashcards
Elevation of the eye is the primary action. Also adducts and intorts.
Superior rectus
Adducts the eye
Medial rectus
Abducts the eye
Lateral rectus
Depression of the eye is the primary action. Also adducts and extorts.
Inferior rectus
Depression of the eye is the primary action. Also abducts and intorts.
Superior oblique
Elevation of the eye is the primary action. Also abducts and extorts.
Inferior oblique
Symmetrical or synchronous movement of the eyes
Conjugate movement
Movement of the eyes in opposite direction
Disconjugate movement
The six recognized eye movement control systems
Vestibulo-ocular reflex, Optokinetic, Saccadic, Smooth pursuit, Fixation & Vergence “VOSS FV”
Controls the degree of convergence or divergence of the eyes, maintaining macular fixation no matter what the distance to the target.
Vergence
Proper _______ of both eyes on the visual target permits fusion of both retinal images into one visual image.
Fixation
Pathways mediate fixation and fusion
Retino-occipito-tegmental (ROT) and reticulo-occipito-fronto-tegmental (ROFT) pathways
Produces conjugate eye movements of equal magnitude but in the opposite direction to compensate for head movements in order to maintain foveation during motion of the head. Also called eye counterrolling.
Vestibulo-ocular reflex
Occurs in a comatose patient who cannot fixate.
Doll’s eye maneuver
A positive doll’s means that the ____________ is intact.
Vestibuloproprioceptive counterrolling reflex
Ensures that the fovea maintains fixation on the object of interest.
Supranuclear control of eye movements
Cortical areas involved in the generation of saccades
Supplemental eye field, Posterior eye field(parietal lobe) & Frontal eye field “SPF”
Controls horizontal saccades to the opposite side
Frontal Eye field
A prominent fiber tract that unites the oculomotor, trochlear and the abducens nuclei. Runs in the midline in the _________ of the brainstem.
Medial Longitudinal Folds. Dorsal tegmentum.
In MLF: crosses the ____, soon after beginning its ascent to the contralateral ______________.
Pons. Third nerve complex.
In MLF: coordinate movements of the _____, as well as head and eye, and even body movements.
2 eyes
Enumerate oculomotor pathways
Frontopontine, Medial Longitudinal Fasciculus, Parapontine Folicular “FMP”
Vertical gaze. Upgaze and downgaze pathways course in the:
Pretectum, Rostral midbrain & Posterior commissure
In vertical gaze, voluntary vertical movements are the simultaneous activity of both the
Frontal cortical eye fields
Types of peripheral part
Infranuclear
Types of central part
Internuclear & Supranuclear
Involvements of peripheral disorder
Extraocular muscles, CN nuclei & CN fascicles “ECC”
CN IV: trochlear. Type of pathway
GSE: superior oblique
Contralateral MR does not receive a signal to contract. As a result, gaze to one side results in _______ of the eye ipsilateral to PPRF, with no _________ of contralateral eye.
Internuclear Opthalmoplegia
In Internuclear Opthalmoplegia, there may be nystagmus of the _________. Bilateral INO = ______(wall eyed bilateral INO) INO is labeled by the side with ________. Common in MS and brainstem strokes.
Abducting eye. WEBINO. Adduction failure.
Occurs with midline pontine lesions. The only movement is ________ of one eye. Common with infarction and demyelinative lesions.
One-and-a-half syndrome. Abduction.
Usually results from a mass lesion involving the region of the posterior third ventricle and upper dorsal midbrain. The pupils may have a poor, rarely absent, light response, and much better near response. The pupils also tend to be large.
Parinaud syndrome
Other name for parinaud syndrome
Sylvian aqueduct syndrome, dorsal midbrain syndrome or the syndrome of the posterior commissure.
Parinaud’s syndrome manifestations
Paralysis of upward gaze, Failure of convergence, Retraction nystagmus & Setting sun sign “PFRS”
Test for evaluating the range of movement of the eyes.
Corneal light reflection/Hirschberg test
Reflex elicited on hirschberg test
Accomodation reflex
Ocular alignment and the visual axes include:
Inspection of limbus to eyelid relationships & corneal light reflection
Inspection while taking the history. Look for malalignment, range and persistence of eye movements, and for hyperkinesis such as nystagmus.
Spontaneous eye movements
Examiner observes steadiness and range of movements after commanding the patient to fixate on a distant object straight ahead and then to move the eyes to the right, left, up and down.
Volitional fixation & movements
Types of visual reflex ocular movements
Smooth pursuit, Alignment lock, Vergences, Optokinetic nystagmus & Reflex fixation “SAVOR”
The patient’s eye pursue the examiner’s finger as it moves through the full range of ocular movements.
Smooth pursuit
The examiner directs the patient to look at ear and distant objects and to follow the examiner’s finger in toward the patient’s nose
Vergences
The patient fixates straight ahead, the the examiner alternately covers and uncovers first one, then the other eye, and looks for deviation in alignment after monocular occlusion of vision (_________ test)
Alignment lock. Cover-uncover test.
Patient fixates on rotating drum or a moving striped strip.
Optokinetic nystagmus
Types of non-visual reflex ocular movements
Positional nystagmus, Contraversive eye-turning test (doll’s eye test, oculo-cephalic test) & Caloric nystagmus “PCC”
Irrigation of ears with hot or cold water
Caloric nystagmus
Placing the patient’s head in various postures
Positional nystagmus
Quick turning of the patient’s head by the examiner’s hands; used im comatose patient.
Contraversive eye-turning test (doll’s eye test, oculo-cephalic test)
2wk hx of headache, low gradef evrr, vomiting and diplopia. Progressive dec in sensorium. Drowsy, arousable & incoherent. Pupils 4mm ESRTL, bilateral papilledema. Bilateral lateral gaze palsy. (+) response to visual threat, bilateral. All extremities spastic, bilateral babinski, clonus. Rigid neck, (+) incontinence.
Tuberculosis meningitis with hydrocephalus
Symptoms gradually progressing 6mos. Associated with vomiting and noted to be “cross eyed”. Pupils 4mm ESRTL, (-)convergence. fundoscopy: bilateral papilledema. No visual field cuts; VA: UO 20/30. Persistently downward gaze.
Perinaud’s syndrome secondary to midline tumor probably germinoma
