Neuro 13 Flashcards

Which muscle group moves the eyes within the orbits?

A. Internal ocular muscles
B. Ciliary body muscles
C. Extraocular muscles
D. Pupillary sphincter muscles

Internal ocular muscles primarily control:

A. Eyelid elevation and closure
B. Pupillary size and accommodation
C. Globe movement within orbit
D. Lacrimal secretion and blinking

Nuclear/infranuclear ocular motor pathways include:

A. Cortex, thalamus, cerebellum
B. Retina, LGN, visual cortex
C. Forebrain circuits, LGN, visual cortex
D. Nuclei, nerves, and muscles

Supranuclear ocular motor pathways include:

A. Peripheral nerves and muscles
B. Brainstem and forebrain circuits
C. Retina and thalamus only
D. Orbit and extraocular fascia

Both nuclear/infranuclear and supranuclear ocular pathways ultimately involve brainstem nuclei of:

A. II, III, and IV
B. III, IV, and VI
C. III, V, and VII
D. IV, V, and VI

The lateral, superior, medial, and inferior rectus muscles insert onto the:

A. Cornea
B. Lens capsule
C. Tarsal plate
D. Sclera

Which of the following best describes the anatomical path (origin, pulley, and insertion) of the superior oblique muscle?

A. Originates from the body of the sphenoid, passes through the trochlea, and inserts on the superior-lateral globe.

B. Originates from the body of the sphenoid, passes through the annulus of Zinn, and inserts on the inferior globe.

C. Originates from the medial orbital wall, passes through the trochlea, and inserts on the superior globe.

D. Originates from the maxilla, passes through the annulus of Zinn, and inserts on the lateral globe.

Intorsion is:

A. Downward movement of the eye
B. Nasal deviation of the globe
C. Upper pole moves inward
D. Upper pole moves outward

Extorsion is:

A. Medial rotation of lower pole
B. Upper pole moves outward
C. Lateral translation of globe
D. Downward movement in abduction

Which of the following best describes the anatomical origin and insertion of the inferior oblique muscle?

A. Originates from the anterior medial orbital floor (maxilla) and inserts on the inferolateral globe.

B. Originates from the orbital apex (annulus of Zinn) and inserts on the inferior sclera.

C. Originates from the sphenoid bone, passes through the trochlea, and inserts inferiorly.

D. Originates from the common tendinous ring and inserts on the superior globe.

Abduction (lateral) movement of eye

Adduction (medial) movement of eye

Elevation and intorsion

Depression and extorsion

Elevation and extorsion

Depression and intorsion

Levator palpebrae superioris primarily:

A. Elevates the eyelid
B. Constricts the pupil
C. Abducts the eye
D. Accommodates the lens

The ciliary muscle primarily:

A. Abducts the globe
B. Elevates the eyelid
C. Adjusts lens thickness
D. Constricts the palpebral fissure

CN III, IV, and VI pass through the _____ and enter the orbit via the _____.

A. Optic canal; orbital apex
B. Jugular foramen; optic canal
C. Foramen rotundum; fissure
D. Cavernous sinus; superior orbital fissure

The superior division of the oculomotor nerve innervates the:

A. Medial rectus and inferior rectus
B. Levator and superior rectus
C. Inferior oblique and levator
D. Superior rectus and medial rectus

The inferior division of the oculomotor nerve supplies the:

A. Medial rectus, inferior rectus, inferior oblique
B. Superior rectus, inferior rectus, inferior oblique
C. Lateral rectus and inferior rectus
D. Superior oblique and medial rectus

The inferior division of CN III carries which fibers to which targets?

A. Motor fibers to lateral rectus
B. Sensory fibers to cornea
C. Preganglionic parasympathetics to pupil and ciliary muscle
D. Postganglionic sympathetics to iris dilator

The Edinger-Westphal nucleus contains:

A. Branchial motor neurons
B. Preganglionic parasympathetic neurons
C. General sensory neurons
D. Somatic sensory neurons

Parasympathetic fibers from the Edinger–Westphal nucleus are especially vulnerable to aneurysms of the:

A. Posterior communicating artery
B. Anterior cerebral artery
C. Superior cerebellar artery
D. Middle cerebral artery

A painful oculomotor palsy with pupillary involvement should raise greatest concern for:

A. Cavernous sinus thrombosis
B. Diabetic neuropathy
C. Posterior communicating aneurysm
D. Myasthenia gravis

Can unilateral weakness of levator palpebrae superioris and pupillary dilator muscles be caused by a single unilateral lesion?

A. Yes, usually
B. Yes, always
C. Sometimes
D. No

The trochlear nuclei lie at the level of the:

A. Superior colliculi and red nucleus
B. Inferior colliculi and SCP decussation
C. Facial colliculi and MLF
D. Obex and pyramidal decussation

Which cranial nerve exits the brainstem dorsally and has crossed fibers?

A. Oculomotor nerve
B. Abducens nerve
C. Trochlear nerve
D. Trigeminal nerve

Trochlear nerves are particularly susceptible to compression from:

A. Cerebellar tumors
B. Pituitary adenomas
C. ICA aneurysms
D. Vestibular schwannomas

The abducens nerve exits the dura and enters:

A. Meckel’s cave
B. Internal auditory meatus
C. Cavernous sinus
D. Dorello’s canal

The abducens nerve is especially susceptible to injury from:

A. Lateral brain shift and high ICP
B. Downward traction and high ICP
C. Basilar thrombosis and low ICP
D. Optic nerve edema and low ICP

From distal to proximal, causes of diplopia include fracture, then:

A. NMJ, muscles, CN palsies
B. CN palsies, muscles, NMJ
C. Muscles, NMJ, CN palsies
D. CN palsies, NMJ, muscles

Injury to an extraocular muscle most directly causes:

A. Dysconjugate gaze
B. Monocular blindness
C. Miosis
D. Visual field loss

Abnormal lateral deviation of one eye is called:

A. Esotropia
B. Hypertropia
C. Phoria
D. Exotropia

Abnormal medial deviation of one eye is called:

A. Exotropia
B. Esotropia
C. Hypertropia
D. Amblyopia

Vertical deviation of one eye is called:

A. Esotropia
B. Exotropia
C. Hypertropia
D. Phoria

A penlight shone at both eyes shows asymmetric corneal reflections. This suggests:

A. Subtle dysconjugate gaze
B. Papilledema
C. Afferent pupillary defect
D. Monocular blindness

A mild latent weakness revealed only when one eye is covered is called:

A. Exotropia
B. Hypertropia
C. Amblyopia
D. Phoria

Amblyopia is:

A. Vertical misalignment
B. Decreased vision in one eye
C. Latent ocular drift
D. Diplopia on lateral gaze

With a complete CN III palsy, the eye can still perform:

A. Abduction, depression, intorsion
B. Adduction, elevation, extorsion
C. Abduction, elevation, extorsion
D. Adduction, depression, intorsion

Injury to the oculomotor nerve causes _____ of the pupil.

A. Constriction
B. Hippus
C. Normal size
D. Dilation

Diplopia that is worse when looking at near objects rather than far objects suggests:

A. Trochlear palsy
B. Oculomotor palsy
C. Abducens palsy
D. Vestibular dysfunction

Diagonal diplopia that worsens when looking up and medially is most consistent with:

A. Abducens palsy
B. Trochlear palsy
C. Oculomotor palsy
D. Horner syndrome

Herniation of the medial temporal lobe over the tentorium cerebelli can compress the:

A. Oculomotor nerve
B. Optic tract
C. Trochlear nerve
D. Trigeminal nerve

In all suspected cases of oculomotor nerve palsy, which studies should be ordered?

A. EEG and lumbar puncture
B. EMG and NCS
C. CT perfusion and PET
D. CTA and MRA

Aneurysmal oculomotor palsy classically involves the:

A. Corneal reflex
B. Pupil
C. Facial sensation
D. Visual field

Pupil-sparing oculomotor palsy is most likely caused by:

A. Uncal herniation
B. Cavernous sinus tumor
C. Diabetes or microvascular neuropathy
D. Posterior communicating aneurysm

A patient has ptosis, a “down and out” eye, and a dilated pupil. The most concerning cause is:

A. Posterior communicating aneurysm
B. Thyroid eye disease
C. Orbital floor fracture
D. Myasthenia gravis

Horizontal diplopia after elevated intracranial pressure most likely reflects injury to:

A. Trochlear nerve
B. Oculomotor nerve
C. Optic nerve
D. Abducens nerve

The oculomotor nuclei are located at the level of the:

A. Superior colliculi and red nuclei
B. Inferior colliculi and SCP decussation
C. Facial colliculi and vestibular nuclei
D. Obex and pyramidal decussation

Relative to the cerebral aqueduct, the oculomotor nuclei lie:

A. Dorsal to tectum
B. Lateral to crus cerebri
C. Ventral to periaqueductal gray
D. Within the red nucleus

The abducens nuclei lie:

A. In the rostral midbrain
B. In the upper medulla
C. In the lateral tegmentum
D. On the floor of the fourth ventricle

The abducens nuclei are located in the:

A. Upper/mid pons
B. Mid/lower pons
C. Upper medulla
D. Cervicomedullary junction

The dorsal subnuclei of the oculomotor nucleus innervate the:

A. Ipsilateral Medial rectus
B. Ipsilateral Inferior rectus
C. Contralateral Inferior rectus
D. Contralateral Medial rectus

The intermediate subnuclei of the oculomotor nucleus innervate the ipsilateral:

A. Ipsilateral Medial oblique
B. Ipsilateral Inferior oblique
C. Contralateral Inferior oblique
D. Contralateral Medial oblique

The ventral subnuclei of the oculomotor nucleus innervate the:

A. Ipsilateral Medial rectus
B. Ipsilateral Inferior rectus
C. Contralateral Inferior rectus
D. Contralateral Medial rectus

The Edinger-Westphal subnucleus innervates the pupillary constrictors and ciliary muscles on the:

A. Ipsilateral side
B. Bilateral sides
C. Contralateral side
D. Side of gaze only

The central caudal subnucleus supplies the levator palpebrae superioris:

A. Bilaterally
B. Ipsilaterally
C. Contralaterally
D. With no decussation

A nuclear lesion affecting the medial subnucleus would most directly weaken the:

A. Ipsilateral superior rectus
B. Bilateral superior recti
C. Ipsilateral medial rectus
D. Contralateral superior rectus

Which is a supranuclear cause of diplopia?

A. Orbital fracture
B. Oculomotor palsy
C. Internuclear ophthalmoplegia
D. Myasthenia gravis

Which is also listed as a supranuclear cause of diplopia?

A. Skew deviation
B. Superior oblique myositis
C. Cavernous sinus lesion
D. Thyroid eye disease

Which additional category is included among supranuclear causes of diplopia in this material?

A. Neuromuscular junction disease
B. Ingestion of toxins
C. Orbital pseudotumor
D. Ocular trauma

In mild dysconjugate gaze, patients may have only:

A. Complete ophthalmoplegia
B. Monocular blindness
C. Polyopia
D. Visual blurring

Monocular diplopia or polyopia is not caused by:

A. Ophthalmologic disease
B. Visual cortex disorders
C. Eye movement abnormalities
D. Psychiatric conditions

In oculomotor nerve palsy, the eye typically rests in a:

A. Down and out position
B. Up and out position
C. Down and in position
D. Midline fixed position

Complete ptosis requiring manual lid elevation is most suggestive of:

A. Trochlear palsy
B. Horner syndrome
C. Oculomotor palsy
D. Abducens palsy

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Trochlear nerve palsy produces vertical diplopia because of loss of:

A. Elevation and extorsion
B. Adduction and elevation
C. Depression and extorsion
D. Depression and intorsion

A patient improves diplopia by looking up and tilting the head away from the affected eye. This pattern suggests:

A. Oculomotor palsy
B. Trochlear palsy
C. Abducens palsy
D. Internuclear ophthalmoplegia

Vertical diplopia in trochlear nerve palsy is usually worst when the eye looks:

A. Downward and nasally
B. Upward and temporally
C. Straight ahead only
D. Laterally and upward

Which finding supports trochlear nerve palsy?

A. Affected eye has esotropia
B. Diplopia improves on downgaze
C. Affected eye has hypertropia
D. Head tilt toward lesion helps

A patient sees two pen lines, with the lower line tilted, and has had a subtle compensatory head tilt since childhood but diplopia in adulthood. The best diagnosis is:

A. Acute abducens palsy
B. Myasthenia gravis
C. Oculomotor fascicular lesion
D. Congenital trochlear palsy

Vertical disparity of the eyes due to a supranuclear lesion is called:

A. Esotropia
B. Skew deviation
C. Exotropia
D. Phoria

Skew deviation can result from lesions in the:

A. Cerebellum, brainstem, or inner ear
B. Orbit, retina, or lens
C. Cortex, chiasm, or tract
D. Pons, cord, or cortex

Lesions of the abducens nerve classically produce:

A. Vertical diplopia
B. Monocular diplopia
C. Horizontal diplopia
D. Torsional diplopia

Diplopia that improves at near but worsens at distance most strongly suggests:

A. Oculomotor palsy
B. Trochlear palsy
C. Abducens palsy
D. Horner syndrome

Diplopia that worsens when the affected eye abducts is most consistent with:

A. Trochlear palsy
B. Abducens palsy
C. Oculomotor palsy
D. Skew deviation

The abducens nerve is especially vulnerable to:

A. Downward traction from elevated ICP
B. Medial traction from aneurysm
C. Upward herniation from edema
D. Lateral stretch from trauma

A pontine infarct affecting abducens pathways most likely causes:

A. Contralateral adduction weakness
B. Bilateral ptosis
C. Ipsilateral abduction weakness
D. Contralateral vertical diplopia

A lesion of the abducens nucleus may also produce facial weakness because of nearby involvement of:

A. CN V nucleus
B. CN VII nucleus
C. CN IX nucleus
D. CN XII nucleus

Light entering one eye activates retinal ganglion cells that project to:

A. The ipsilateral optic tract
B. The contralateral optic tract
C. Both optic tracts
D. The lateral geniculate only

The pupillary light reflex travels centrally in the _____ pathway through the _____ of the superior colliculus.

A. Geniculocalcarine; tectum
B. Extrageniculate; brachium
C. Retinogeniculate; crus
D. Spinothalamic; tegmentum

The pupillary light reflex reaches the:

A. Pretectal area
B. Lateral geniculate body
C. Superior salivatory nucleus
D. Solitary nucleus

Relative to the oculomotor nuclei, the Edinger-Westphal nuclei lie:

A. Ventral and posterior
B. Lateral and inferior
C. Dorsal and anterior
D. Medial and caudal

Which list gives all three components of accommodation?

A. Dilation, divergence, blinking
B. Constriction, lens accommodation, convergence
C. Miosis, abduction, convergence
D. Adduction, constriction, tearing

The accommodation response is initiated by visual signals relayed to the:

A. Pretectal area
B. Superior colliculus
C. Visual cortex
D. Red nucleus

The descending sympathetic pathway for pupillary dilation activates preganglionic neurons in the:

A. Dorsal horn
B. Edinger-Westphal nucleus
C. Intermediolateral column
D. Ciliary ganglion

Preganglionic sympathetic fibers reach the paravertebral chain through the:

A. Gray rami communicantes
B. White rami communicantes
C. Internal carotid plexus
D. Dorsal roots

Postganglionic sympathetic fibers to the pupillary dilator arise from the:

A. Ciliary ganglion
B. Pterygopalatine ganglion
C. Stellate ganglion
D. Superior cervical ganglion

Postganglionic sympathetic fibers ascend to the cavernous sinus and then innervate the:

A. Pupillary constrictor muscle
B. Ciliary muscle
C. Pupillary dilator muscle
D. Medial rectus muscle

The sympathetic pathway also innervates Müller’s muscle, which:

A. Constricts the pupil
B. Elevates the upper eyelid
C. Depresses the lower eyelid
D. Adducts the globe

Asymmetry of pupil size is called:

A. Anisocoria
B. Amblyopia
C. Astigmatism
D. Hemianopia

Injury to the Edinger-Westphal nuclei can cause a:

A. Bilaterally constricted pupil
B. Unilaterally dilated pupil
C. Bilateral Marcus Gunn pupil
D. Small reactive pupil

Ptosis in Horner syndrome is due to denervation of:

A. Levator palpebrae superioris
B. Superior rectus
C. Müller’s muscle
D. Orbicularis oculi

Miosis in Horner syndrome is caused by loss of sympathetic input to the:

A. Pupillary constrictor
B. Pupillary dilator
C. Ciliary muscle
D. Superior tarsal muscle

Anisocoria that is more obvious in the dark suggests:

A. Oculomotor lesion
B. Marcus Gunn pupil
C. Horner syndrome
D. Pontine lesion

Pupillary dilation after hydroxyamphetamine drops indicates a:

A. Postganglionic lesion
B. Preganglionic lesion
C. Optic tract lesion
D. Midbrain lesion

The absence of anhidrosis favors a _____ sympathetic lesion.

A. Central
B. Preganglionic
C. Diffuse
D. Postganglionic

Bilateral small but light-reactive pupils are most consistent with lesions of the:

A. Midbrain
B. Pons
C. Optic nerves
D. Cavernous sinus

An absent direct response with a normal consensual response is characteristic of:

A. Horner syndrome
B. Argyll Robertson pupils
C. Marcus Gunn pupils
D. Oculomotor palsy

Marcus Gunn pupils result from injury to the:

A. Optic nerve, retina, or eye
B. Oculomotor nerve, iris, or lens
C. Optic chiasm, tract, or cortex
D. Pons, medulla, or cerebellum

A lesion at or behind the optic chiasm would produce Marcus Gunn pupils:

A. Always
B. Usually
C. Sometimes
D. Never

The best bedside test for Marcus Gunn pupils is the:

A. Doll’s eye test
B. Swinging flashlight test
C. Cover-uncover test
D. Head impulse test

During the swinging flashlight test, paradoxical dilation every few seconds suggests:

A. Horner syndrome
B. Pontine pupils
C. Marcus Gunn pupils
D. Oculomotor palsy

A patient with optic neuritis has a relative afferent pupillary defect. Can optic nerve or retinal disease itself explain anisocoria?

A. Yes, commonly
B. Only if bilateral
C. Only with retinal detachment
D. No

Benign anisocoria is usually defined by a pupil asymmetry of:

A. Less than 0.6 mm
B. Less than 1.5 mm
C. Greater than 0.6 mm
D. Greater than 2.0 mm

A patient found unresponsive has bilateral pinpoint pupils. Which intoxication is most likely?

A. Anticholinergics
B. Cocaine
C. Opiates
D. Amphetamines

Barbiturate overdose classically causes:

A. Bilateral fixed dilated pupils
B. Bilateral small pupils
C. Unilateral blown pupil
D. Alternating anisocoria

A dilated pupil constricts with 1% pilocarpine. This finding supports:

A. Muscarinic blockade
B. Sympathetic overactivity
C. Optic neuropathy
D. Parasympathetic lesion

The classic light-near dissociation pupil associated with neurosyphilis is the:

A. Argyll Robertson pupil
B. Adie tonic pupil
C. Marcus Gunn pupil
D. Horner pupil

Degeneration of the ciliary ganglion or postganglionic parasympathetic neurons causes a mid-dilated pupil known as:

A. Argyll Robertson pupil
B. Adie myotonic pupil
C. Marcus Gunn pupil
D. Midbrain corectopia

A pupil that is irregular and off-center suggests the rare disorder:

A. Adie myotonic pupil
B. Argyll Robertson pupil
C. Midbrain corectopia
D. Horner syndrome

Opening of the eye is mediated primarily by:

A. Levator and Müller muscles
B. Orbicularis and levator
C. Superior rectus and levator
D. Orbicularis and superior tarsal

Eye closure is produced by the _____ muscle innervated by _____.

A. Levator palpebrae; CN III
B. Müller; sympathetics
C. Frontalis; CN VII
D. Orbicularis oculi; CN VII

Mild ptosis is most suggestive of:

A. Myasthenia gravis
B. Horner syndrome
C. Oculomotor palsy
D. Facial nerve palsy

Ptosis that worsens with sustained upgaze most strongly suggests:

A. Horner syndrome
B. Oculomotor lesion
C. Myasthenia gravis
D. Cavernous sinus syndrome

Bilateral ptosis without loss of consciousness suggests a dorsal lesion affecting the:

A. Central caudal nucleus
B. Red nucleus
C. Edinger-Westphal nucleus
D. Pretectal area

The cavernous sinus lies between the _____ and _____ layers of dura.

A. Arachnoid and meningeal
B. Periosteal and dural
C. Dural and pial
D. Periosteal and arachnoid

Within the cavernous sinus, the nerve closest to the carotid siphon is the:

A. Oculomotor nerve
B. Trochlear nerve
C. Abducens nerve
D. Ophthalmic nerve

The orbital apex is the region where orbital _____ converge.

A. Nerves, arteries, and veins
B. Muscles, nerves, and lens
C. Veins, ducts, and retina
D. Arteries, chiasm, and veins

Cavernous sinus syndrome classically disrupts:

A. CN II, III, IV
B. CN III, V1, V2
C. CN II, IV, VI
D. CN III, IV, VI

The first nerve typically affected by a cavernous carotid aneurysm is the:

A. Oculomotor nerve
B. Trochlear nerve
C. Abducens nerve
D. Optic nerve

Supranuclear output from CN III, IV, and VI systems generates which eye movements?

A. Horizontal, vertical, vergence
B. Saccadic, smooth, vestibular
C. Horizontal, torsional, pursuit
D. Fixation, blinking, vergence

Stable viewing of a moving target is mediated by:

A. Vergence
B. Saccades
C. Vestibulo-ocular reflex
D. Smooth pursuit

The oculomotor and trochlear nuclei are in the _____, whereas the abducens nucleus is in the _____.

A. Pons; medulla
B. Medulla; midbrain
C. Midbrain; pons
D. Midbrain; medulla

The tract interconnecting eye movement nuclei with vestibular nuclei is the:

A. Medial longitudinal fasciculus
B. Trigeminothalamic tract
C. Medial lemniscus
D. Spinothalamic tract

A dilated pupil fails to constrict after 1% pilocarpine. This most strongly suggests:

A. Preganglionic parasympathetic lesion
B. Muscarinic blockade
C. Adie myotonic pupil
D. Edinger-Westphal injury

_____ are rapid eye movements reaching velocities of up to 700° per second

_____ eye movements maintain fused fixation by both eyes as targets move toward or away from the viewer

_____ is a rhythmic form of reflex eye movements composed of slow eye movements in one direction interrupted repeatedly by fast, saccade-like eye movements in the opposite direction.