Module 5: Ocular Motility & Disorders Flashcards Preview

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Flashcards in Module 5: Ocular Motility & Disorders Deck (50)
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0
Q

Elevation of the eye is the primary action. Also adducts and intorts.

A

Superior rectus

1
Q

Adducts the eye

A

Medial rectus

2
Q

Abducts the eye

A

Lateral rectus

3
Q

Depression of the eye is the primary action. Also adducts and extorts.

A

Inferior rectus

4
Q

Depression of the eye is the primary action. Also abducts and intorts.

A

Superior oblique

5
Q

Elevation of the eye is the primary action. Also abducts and extorts.

A

Inferior oblique

6
Q

Symmetrical or synchronous movement of the eyes

A

Conjugate movement

7
Q

Movement of the eyes in opposite direction

A

Disconjugate movement

8
Q

The six recognized eye movement control systems

A

Vestibulo-ocular reflex, Optokinetic, Saccadic, Smooth pursuit, Fixation & Vergence “VOSS FV”

9
Q

Controls the degree of convergence or divergence of the eyes, maintaining macular fixation no matter what the distance to the target.

A

Vergence

10
Q

Proper _______ of both eyes on the visual target permits fusion of both retinal images into one visual image.

A

Fixation

11
Q

Pathways mediate fixation and fusion

A

Retino-occipito-tegmental (ROT) and reticulo-occipito-fronto-tegmental (ROFT) pathways

12
Q

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.

A

Vestibulo-ocular reflex

13
Q

Occurs in a comatose patient who cannot fixate.

A

Doll’s eye maneuver

14
Q

A positive doll’s means that the ____________ is intact.

A

Vestibuloproprioceptive counterrolling reflex

15
Q

Ensures that the fovea maintains fixation on the object of interest.

A

Supranuclear control of eye movements

16
Q

Cortical areas involved in the generation of saccades

A

Supplemental eye field, Posterior eye field(parietal lobe) & Frontal eye field “SPF”

17
Q

Controls horizontal saccades to the opposite side

A

Frontal Eye field

18
Q

A prominent fiber tract that unites the oculomotor, trochlear and the abducens nuclei. Runs in the midline in the _________ of the brainstem.

A

Medial Longitudinal Folds. Dorsal tegmentum.

19
Q

In MLF: crosses the ____, soon after beginning its ascent to the contralateral ______________.

A

Pons. Third nerve complex.

20
Q

In MLF: coordinate movements of the _____, as well as head and eye, and even body movements.

A

2 eyes

21
Q

Enumerate oculomotor pathways

A

Frontopontine, Medial Longitudinal Fasciculus, Parapontine Folicular “FMP”

22
Q

Vertical gaze. Upgaze and downgaze pathways course in the:

A

Pretectum, Rostral midbrain & Posterior commissure

23
Q

In vertical gaze, voluntary vertical movements are the simultaneous activity of both the

A

Frontal cortical eye fields

24
Q

Types of peripheral part

A

Infranuclear

25
Q

Types of central part

A

Internuclear & Supranuclear

26
Q

Involvements of peripheral disorder

A

Extraocular muscles, CN nuclei & CN fascicles “ECC”

27
Q

CN IV: trochlear. Type of pathway

A

GSE: superior oblique

28
Q

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.

A

Internuclear Opthalmoplegia

29
Q

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.

A

Abducting eye. WEBINO. Adduction failure.

30
Q

Occurs with midline pontine lesions. The only movement is ________ of one eye. Common with infarction and demyelinative lesions.

A

One-and-a-half syndrome. Abduction.

31
Q

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.

A

Parinaud syndrome

32
Q

Other name for parinaud syndrome

A

Sylvian aqueduct syndrome, dorsal midbrain syndrome or the syndrome of the posterior commissure.

33
Q

Parinaud’s syndrome manifestations

A

Paralysis of upward gaze, Failure of convergence, Retraction nystagmus & Setting sun sign “PFRS”

34
Q

Test for evaluating the range of movement of the eyes.

A

Corneal light reflection/Hirschberg test

35
Q

Reflex elicited on hirschberg test

A

Accomodation reflex

36
Q

Ocular alignment and the visual axes include:

A

Inspection of limbus to eyelid relationships & corneal light reflection

37
Q

Inspection while taking the history. Look for malalignment, range and persistence of eye movements, and for hyperkinesis such as nystagmus.

A

Spontaneous eye movements

38
Q

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.

A

Volitional fixation & movements

39
Q

Types of visual reflex ocular movements

A

Smooth pursuit, Alignment lock, Vergences, Optokinetic nystagmus & Reflex fixation “SAVOR”

40
Q

The patient’s eye pursue the examiner’s finger as it moves through the full range of ocular movements.

A

Smooth pursuit

41
Q

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

A

Vergences

42
Q

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)

A

Alignment lock. Cover-uncover test.

43
Q

Patient fixates on rotating drum or a moving striped strip.

A

Optokinetic nystagmus

44
Q

Types of non-visual reflex ocular movements

A

Positional nystagmus, Contraversive eye-turning test (doll’s eye test, oculo-cephalic test) & Caloric nystagmus “PCC”

45
Q

Irrigation of ears with hot or cold water

A

Caloric nystagmus

46
Q

Placing the patient’s head in various postures

A

Positional nystagmus

47
Q

Quick turning of the patient’s head by the examiner’s hands; used im comatose patient.

A

Contraversive eye-turning test (doll’s eye test, oculo-cephalic test)

48
Q

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.

A

Tuberculosis meningitis with hydrocephalus

49
Q

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.

A

Perinaud’s syndrome secondary to midline tumor probably germinoma