Assessing Specific Cranial Nerves III, IV, V, and VI

Question 1

Primary function of the ______________ is to coordinate eye movements by interconnecting the nuclei of C.N. III, IV, and VI

Answer 1

Medial Longitudinal Fasciculus

Question 2

Diseases that effect the interconnecting pathways of MLF may produce a characteristic _____________

Answer 2

Internuclear ophthalmoplegia

Question 3

Disease that effects the MLF. Causes a person to be unable to laterally gaze and has no abnormality noted on convergence

Answer 3

Multiple sclerosis

Convergence only requires bilateral C.N. III

Question 4

Supranuclear pathway for mostly rapid or darting (saccadic) eye movement is from the _________ lobe

Answer 4

Frontal

Question 5

Supranuclear pathway for controlling mostly smooth or following eye movement is found in the ________ lobe

Answer 5

Occipital

Question 6

The result of uncoordinated attempts at controlling eye movement, with the fast component representing saccadic movement and the slow portion representing following movement

Answer 6

Nystagmus

Question 7

Disease of this C.N. is usually more obvious due to the accompanying parasympathetic manifestations

Answer 7

C.N. III

Question 8

Examples of parasympathetic manifestations from disease of C.N. III

Answer 8

Ptosis and corectasia

Question 9

Diseases of this C.N. causes difficulty for the patient when looking down and in

Answer 9

C.N. IV

Question 10

Disease of this C.N. makes the patient unable to laterally deviate the eye on the same side of the lesion

Answer 10

C.N. VI

Question 11

Disease of C.N. II will diminish pupilloconstriction with ____________ due to decreased sensory perception. However, exposure to the unaffected side should cause brisk ___________________

Answer 11

Bilateral symmetry

Bilateral pupilloconstriction

Question 12

Pathological involvement of C.N III results in a decreased ability to carry out pupilloconstriction in the _________ eye

Answer 12

Ipsilateral

Question 13

Loss of diencephalon of midbrain function results in unopposed ______________ dominance, light as a stimulus causes no ___________ and the pupil is _____________.

Answer 13

Sympathetic
Pupilloconstriction
Fixed and dilated

Question 14

Bilaterally fixed and dilated pupils upon exposure to a light stimulus would indicate what clinically?

Answer 14

Brain dead patient

Question 15

Pupil that reacts to light very slowly, remains constricted longer, then dilates slowly. Occurs most often in young women and is considered a benign finding

Answer 15

Holmes-Adie syndrome (Adie’s Pupil/ Tonic pupil)

Question 16

Pupil that reacts only to accomodation. It has neither a direct nor indirect reaction to light. Once though to be pathognomonic of tabes dorsalis (neurosphylis), but it has now been found to occur as a diabetic complication

Answer 16

Argyll-Robertson pupil

Question 17

Causes sympathetic hypofunction often due to lesions of the neck proximal to the carotid artery bifurcation that compresses ascending sympathetic fibers

Answer 17

Horner’s syndrome

Question 18

Signs and symptoms of Horner’s syndrome

Answer 18

• Ptosis (paralysis of superior tarsal muscle)
• Pupilloconstriction(unopposed C.N. III pupilloconstriction)
• Facial anhydrosis (denervation of the sweat glands in the ipsilateral side of the face)
• Ipsilateral facial vasodilation )red or flushed look and a palpable increase in skin temperature)

Question 19

Lesions along the sympathetic pathwya distal to the bifurcation of the common carotid arteries will cause only _____________ and _________, if it is occurring along the ____________ pathway

Answer 19

Pupilloconstriction
Ptosis
internal carotid

Question 20

Symptoms present if the lesion occurs along the external carotid pathway distal to the carotid bifurcation

Answer 20

Vasodilation

Anhydrosis

Question 21

An inward sinking of the eyeball n the eye socket, theoretically a part of sympathetic paralysis due to disruption of sympathetic contractile impulses to the small muscle of Muller

Answer 21

Enopthalmos