Quiz 7 Practice Problems

Question 1

Answer 1

Question 2

Answer 2

Question 3

Answer 3

Question 4

Answer 4

Question 5

Answer 5

Question 6

Answer 6

Question 7

Answer 7

Question 8

Answer 8

Question 9

what is an epidural hemorrhage

Answer 9

Question 10

what is a Subdural hemorrhage

Answer 10

Question 11

what is a subarachnoid hemorrhage

Answer 11

Question 12

what is a stroke? and what are the two types?

Answer 12

Question 13

Answer 13

E. Subdural hematoma due to a torn bridging vein coursing from the cerebrum to a dural sinus

Question 14

Answer 14

E. Middle meningeal artery hemorrhaging into the epidural space

Question 15

Answer 15

Question 16

Answer 16

Question 17

Answer 17

D. Midbrain

Question 18

Answer 18

B. 2

Question 19

The eye close

Answer 19

Question 20

The eye open

Answer 20

Question 21

the spinal chord section

Answer 21

Question 22

the flashlight in the eye

Answer 22

Question 23

movie theatre

Answer 23

Question 24

Answer 24

Question 25

Answer 25

A. CN II and CN III

Question 26

Answer 26

Question 27

Answer 27

Question 28

Answer 28

Question 29

Answer 29

Question 30

Answer 30

Question 31

Anatomical and clinical movements of the eye and the nerves that innervate the muscles of the eye

Answer 31

Dilator pupillary muscle is sympathetics

Sphinter pupillary is CN III

Superior Tarsal is Sympathetics

Levator papebrae superioris is CNIII

Orbicularis Oculi is CN VII

ophthalmic nerve is CN V

Question 32

Multiple sclerosis (MS) is an autoimmune disorder that causes the formation of plaques, inflammation and destruction of myelin sheaths, formed by oligodendrocytes. Identify the nerve most likely affected by a patient with MS.

A.Abducens nerve

B.Greater petrosal nerve

C.Ophthalmic nerve

D.Oculomotor nerve

E.Optic nerve

F.Trochlear nerve

Answer 32

A.Optic nerve (CN II)

Question 33

A 64-year-old man suffers a lesion to his left CN VI. Identify symptom(s) this patient would most likely present with.

A.Anesthesia of forehead

B.Anhydrosis

C.Double vision when looking left

D.Double vision when looking right

E.Eye is positioned down and out

F.Miosis (pin point pupil)

G.Mydriasis (blown/large pupil)

H.Ptosis

I.Vision problems

Answer 33

A.Double vision when looking left

Question 34

A 52-year-old woman suffers a lesion to her left oculomotor nerve. Identify symptom(s) this patient would most likely present with.

A.Anesthesia of forehead

B.Anesthesia of lower lip

C.Anesthesia of mandibular teeth

D.Anesthesia maxillary teeth

E.Anesthesia of upper lip

F.Anosmia

G.Double vision when looking left

H.Double vision when looking right

I.Eye is positioned down and out

J.Miosis (pin point pupil)

K.Mydriasis (blown/large pupil)

L.Ptosis

M.Vision problems

N.Weakness in clenching jaw

Answer 34

A.Eye is positioned down and out

A.Mydriasis (blown/large pupil)

A.Ptosis

Question 35

A 45-year-old woman complains of double vision when looking to the right but not to the left.

Identify the side of the brainstem that is most likely injured.

A.Medulla – left side

B.Medulla – right side

C.Midbrain – left side

D.Midbrain – right side

E.Pons – left side

F.Pons – right side

Answer 35

Pons - right side

CN VI

Question 36

Answer 36

CN III (right)

Question 37

A patient presents with paralysis of the extraoccular eye

muscles. There is an abolition of the corneal reflex but there is

preservation of vision.

The most likely cause of this condition would be fracture of the:

A.foramen rotundum

B.petrous part of temporal bone (internal acoustic meatus)

C.superior orbital fissure (Rochon-Duvigneaud’s syndrome)

D.pterygopalatine fossa (Sluder’s syndrome)

E.maxillary sinus

Answer 37

C. superior orbital fissure (Rochon-Duvigneaud’s syndrome)

Question 38

A patient presents with paralysis of the extraoccular eye

muscles. There is an abolition of the corneal reflex but there is

preservation of vision.

What other symptoms would this patient most likely present

with?

A.Anesthesia (loss of sensation) of the root of the nose, upper eyelid and forehead

B.Anesthesia (loss of sensation) of the upper lip and mouth

C.Anesthesia (loss of sensation) of the lower lip and mouth

D.Facial paralysis (Bell’s palsy)

E.Muscles of mastication paralysis

Answer 38

A.Anesthesia (loss of sensation) of the root of the nose, upper eyelid and forehead

Question 39

1. Frontonasal dysplasia represents a spectrum of disorders characterized by widely spaced eyes, a midline facial cleft and absence of the tip of the nose (see photos). Recent work has implicated loss of function mutations in Alx3 homeobox transcription factors in this disorder. In mice, compound mutations in Alx3/Alx4 cause similar facial clefts. Based on this phenotype, discuss where you would anticipate Alx3 to be expressed in human development and what its normal function might be.

Answer 39

Discussion: The tip of the nose is normally formed by fusion of the medial nasal prominences, with some contribution from the frontal prominence to the more cranial portions. Although in frontonasal dysplasia the face is abnormally wide and the eyes are far apart (suggesting excess production of tissue in the mid-face region), failure to form the tip of the nose would argue that there has been a failure of normal medial nasal prominence fusion and/or a reduction in the amount of this tissue. Studies in mouse (http://www.ncbi.nlm.nih.gov/pubmed/11641221) indicate that both Alx3 and Alx4 are expressed in the medial nasal prominence. Loss of the Alx family of genes results in failure of neural crest migration into the facial prominences, resulting in these structures being both widely spaced and small. Consequently, the medial nasal prominences fail to fuse, resulting in a midline facial cleft.

Question 40

. Although the palatine shelves fuse at the midline of the mouth, cleft lip and cleft palate are most frequently oblique, even in cases of bilateral clefts (see photo). Discuss why this is the case and what events are likely to have not occurred in formation of the face. In cases of bilateral cleft lip, would you anticipate cleft palate to be more or less likely than in the case of a unilateral cleft, and why?

Answer 40

The primary palate is a small wedge of tissue within the mouth that is formed from the medial nasal prominences—structures that also contribute to the philtrum. Failure of this region to fuse to the maxillary prominence is the most common cause of cleft lip. In severe cases, this cleft extends to the palate—but in all cases, it is a lateral cleft that does not extend into the tissue produced by the medial nasal prominence (i.e. it does not extend to the midline). In bilateral cleft lip, this failure has occurred on both sides, leaving tissue of the philtrum and primary palate suspended at the midline. In this case, it is highly likely that the cleft will extend to the primary palate within the mouth.

Question 41

. Several craniofacial syndromes (Apert, Cruzon, Pfeiffer, Muenke) are due to stenosis, or premature fusion of the bones of the skull. Strikingly, all are caused by mutations in components of the Fgf signaling pathway, and are also associated with hand and foot defects—most commonly syndactyly (see image).

Interestingly (and perhaps incidentally), work in bat embryos has implicated sustained Fgf signaling in the development of bat wings compared to bat hind limbs or compared to mouse limbs (see image). In bat limb development, the forelimbs show elongation of the digits and retention of interdigit soft tissues. Based on this model, would you anticipate that the Fgf mutations seen in craniofacial syndromes reflect a gain of function or loss of function in the Fgf signaling pathway and why?

Answer 41

The connection between limb defects and craniofacial defects is not well understood. However, several studies suggest that the mutations seen in Apert syndrome as well as Pfeiffer and Muenke syndromes result in either enhanced affinity of the Fgf-receptor for its normal ligands or a loss of specificity (resulting in the receptor binding multiple ligands), both of which would enhance Fgf signaling. While cross-species comparisons are not always valid, these observations are consistent with the observed increased Fgf expression in the interdigit regions of bat forelimbs, which results in the retention of interdigit tissues and increased cell proliferation. How enhanced Fgf signaling results in stenosis is not clear, but increased proliferation and decreased cell death would be consistent with premature expansion/fusion of the bones of the skull.

Question 42

Answer 42

Answer: D. At point A in this action potential, Vm has reached threshold potential and has triggered the opening of voltage-gated Na+ channels. The resulting Na+ influx is responsible for the rapid, self- perpetuating depolarization phase of the action potential.

Question 43

Answer 43

Answer: C. The rapid depolarization phase is terminated at point B by the inactivation of the voltage-gated Na+ channels and the opening of the voltage-gated K+ channels. The latter results in the efflux of K+ from the cytosol into the extracellular fluid and repolarization of the cell membrane.

Question 44

Which of the following electrical events is characteristic of inhibitory synaptic interactions?

A) A neurotransmitter agent that selectively opens ligand-gated chloride channels is the basis for

an inhibitory postsynaptic potential

B) Because the Nernst potential for chloride is about −70 mV, chloride ions tend to move out of

the cell along its electrochemical gradient

C) A neurotransmitter that selectively opens potassium channels will allow potassium to move into

the cell

D) An increase in the extracellular sodium concentration usually leads directly to an inhibitory

postsynaptic potential

Answer 44

Answer A. Opening of ligand-gated chloride channels and movement of chloride ions into the cell leads to hyperpolarization of the membrane. Neither increasing the extracellular sodium concentration nor the movement of potassium into the cell leads to hyperpolarization of the membrane.

Question 45

3) Which of the following statements concerning the mechanoreceptive receptor potential is/are true?

A) Increase in stimulus energy results in an increase in receptor potential

B) When receptor potential rises above a certain threshold action potentials will appear in the

neuron attached the receptor

C) Number of action potentials generated in the neuron attached to the receptor is proportional to

receptor potential

D) All of the above are correct

Answer 45

Answer D. The receptor potential is defined as the membrane potential of the neuronal receptor. Once the threshold for activation is reached the number of action potentials generated will increase in proportion to the strength of the stimulus until a plateau is reached.

Question 46

4) Transmission of the electrical signal from the dendrites to the soma of a neuron occurs by which of the following?

A) Calcium channels

B) An action potential propagation

C) Electrotonic conduction

D) Synaptic transmission

Answer 46

Answer C. Dendrites have few voltage-gated sodium channels. As such the capability of these structures in generating action potentials is extremely limited. Therefore, the transmission of the electrical signal in the dendrite is via a non action potential mechanism, electrotonic conduction.

Question 47

When a muscle is suddenly stretched, a signal is transmitted over 1a sensory fibers from muscle spindles. Which of the following statements best describes the response elicited by these spindle afferent signals?

A) Contraction of the muscle in which the active spindles are located

B) Relaxation of the muscle in which the active spindles are located

C) Contraction of muscles antagonistic to those in which the active spindles are located

D) Relaxation of intrafusal fibers in the active spindles

Answer 47

Answer A : When a muscle is stretched, signals traveling over Ia sensory fibers will lead to contraction of the muscle in which the active spindles are located. At the same time, the antagonist muscles will be inactivated. The intrafusal fibers in the spindle do not go slack due to the tonic activation of gamma motor neurons by supraspinal systems.

Question 48

Case 1 A 4-year old boy with cerebral palsy and epilepsy is receiving physical therapy in the clinic of Shriner’s Hospital. He develops a seizure that does not resolve and requires treatment for status epilepticus. Diazepam is an appropriate treatment. What patient and drug information would you like before selecting a dose and route of administration for diazepam?

Answer 48

Key Points ! Because intravenous administration of diazepam may be difficult in this patient, alternative administration routes should be considered. Oral administration is impractical in this patient who is seizing. !

The suitability of the rectal route for administration requires knowledge of both the degree of bioavailability (absorption, first-pass elimination) and the time-course of absorption.

Rectally administered diazepam is 90% bioavailable (e.g. well-absorbed, minimal first-pass elimination) and reaches therapeutic concentrations within 10 minutes. Especially if IV placement is challenging, the time to seizure cessation can be similar between intravenous and rectally administered diazepam. !

Intranasal midazalom has also been shown to be an effective means of halting seizures in pediatric patients.

Question 49

A 27 year-old man with spina bifida develops an infection of his intraventricular-peritoneal shunt and requires antimicrobial therapy with vancomycin. He has impaired renal function due to prior vesicoureteral reflux. Vancomycin exhibits time-dependent bacteriocidal activity with persistant effects. It is eliminated primarily by glomerular filtration of unchanged drug and has a typical elimination half-life of 6 hours. Vancomycin is associated with nephrotoxicity. How would you adjust vancomycin dosing for this patient? How will you monitor therapy?

Answer 49

Renal impairment will decrease the clearance rate of renally eliminated drugs. Dosing interval and/or dose should be adjusted to decrease the rate of drug delivery while maintaining appropriate therapeutic concentration-time profiles of the drug. Referencing clinical guidelines and pharmacist consultation is appropriate.

In this case the purpose of drug monitoring is both to ensure adequate therapeutic levels as well as to prevent toxic effects. After dose adjustments, the new steady state drug concentration should be reached within four drug half-lives; trough levels should be drawn just prior to administration of the next dose.

Question 50

A 39 year-old woman with mild hypothyroidism has been maintained on her current dose of levothyroxine for five years. Her most recent thyroid stimulating hormone (TSH) level is now somewhat elevated and suggests subtherapeutic levothyroxine levels. Further questioning reveals that the woman was concerned about potential bone mineral loss with aging, so she began taking an oral calcium supplement 5 months ago. A calcium associated DECREASE in which of the following is the most likely explanation for the change in this patient’s levothyroxine level?

A. Bioavailability

B. Clearance

C. Elimination rate

D. First-pass hepatic metabolism

E. Volume of distribution

Answer 50

A Bioavailability

Levothyroxine absorption from the gastrointestinal tract is sensitive to a number of dietary interactions. Recommendations are that it be taken on an empty stomach 30-60 minutes before breakfast to ensure consistent day-to-day absorption and bioavailability. • Remember that while absorption and bioavailability are not the same thing, absorption contributes to bioavailability. • If a change in elimination of levothyroxine were suspected as the cause for sub-therapeutic levothyroxine levels it would need to be because calcium caused an INCREASE in clearance and elimination rate. • Similarly, if first-pass hepatic metabolism of levothyroxine were suspected as the cause for sub-therapeutic levothyroxine levels it would need to be because calcium caused an INCREASE in in this process.

Question 51

A morbidly obese 63 year-old man with congestive heart failure and atrial fibrillation will receive digoxin therapy. Digoxin has a narrow therapeutic window with the potential for dysrhythmias at elevated plasma levels. Despite its relatively large volume of distribution, digoxin is not concentrated in fat tissue. What would be the most likely anticipated plasma drug levels if digoxin dosing were based on this patient’s total body mass?

A. Sub-therapeutic drug levels

B. Supra-therapeutic drug levels

C. Therapeutic drug levels

Answer 51

B. Supra-therapeutic drug levels

• Since digoxin does not concentrate in fat tissues, adjusting the dose upward to account for this patients increased weight due to fat is likely to cause supra-therapeutic digoxin drug levels. It is therefore not recommended to adjust digoxin dosing based on weight.

Question 52

A 46 year-old man with alcoholic cirrhosis and ascites is receiving diuretic therapy with furosemide. In healthy patients, furosemide has a volume of distribution of 7.7 liters and is 99% protein bound. Hypoproteinemia in this patient results in an increase in furosemide volume of distribution. Which of the following is the most likely affect that the increased volume of distribution will have on drug elimination?

A. Change from 1st-order to 0-order kinetics

B. Change from 0-order to 1st-order kinetics

C. Decreased clearance

D. Decreased half-life

E. Increased clearance

F. Increased half-life

Answer 52

F. Increased half-life

• While an increase in volume of distribution would decrease the elimination rate constant and thus increase the half-life of the drug, it would not be expected to have an effect on elimination kinetics.

A change in the volume of distribution would not be expected to change the clearance of furosemide. However, other organ system dysfunction caused by the liver (and probably kidney) disease could affect clearance.

Question 53

Fancying herself an expert in pharmacokinetics, the 39 year-old woman with hypothyroidism looks up the Clinical Pharmacology of levothyroxine on rxlist.com and notices that the elimination half-life is approximately 7 days. She decides to experiment with once-weekly dosing of her medication. Which of the following best describes the necessary dose adjustment and effect on plasma drug concentration variability as a result of changing to onceweekly levothyroxine dosing?

A. 7 times the daily dose, increased plasma concentration variability

B. 1/7th daily dose, increased plasma concentration variability

C. 7 times the daily dose, decreased plasma concentration variability

D. 1/7th daily dose, decreased plasma concentration variability

E. no change, no change

Answer 53

A. 7 times the daily dose, increased plasma concentration variability

• To achieve the same steady state concentration of levothyroxine, the patient would need to maintain the same overall rate of drug administration by giving 7X the daily dose but only once per week.

The longer interval and larger dose will cause higher peak drug concentrations and lower trough concentrations

Question 54

Answer 54

Question 55

Answer 55

Question 56

Facial Nerves V and VII explain the course and how they overlap!!!!

Answer 56

Question 57

Answer 57

Question 58

Answer 58

Question 59

Answer 59

Question 60

Answer 60

Question 61

Answer 61

Question 62

Answer 62

Question 63

Answer 63

Question 64

A patient suffers injury to the mandibular branch of the trigeminal nerve (CN V-3) during a dental procedure. Identify symptom(s) this patient would most likely present with.

A.Anesthesia of forehead

B.Anesthesia of lower lip

C.Anesthesia of mandibular teeth

D.Anesthesia maxillary teeth

E.Anesthesia of upper lip

F.Anosmia

G.Double vision when looking left

H.Double vision when looking right

I.Eye is positioned down and out

J.Miosis (pin point pupil)

K.Mydriasis (blown/large pupil)

L.Ptosis

M.Vision problems

N.Weakness in clenching jaw

Answer 64

A.Anesthesia of lower lip

B.Anesthesia of mandibular teeth

C.Weakness in clenching jaw

Question 65

A patient suffers a lesion to the nerve within her right stylomastoid foramen inhibiting the function of this nerve.

A. What nerve is effected by this lesion?

B. Will this lesion effect general sensation of the head (if so which part) or

motor function to the head (if so which part)?

C. Will taste be effected by this lesion? Why or why not?

D. Will this patient have any trouble crying on the right side? Why or why not?

E. Will parotid gland function be effected by this lesion? Why or why not?

F. During the physical examination you conduct the pupillary reflex … what

do you expect to observe in your patient?

G. During the physical examination you conduct the corneal reflex … what do

you expect to observe in your patient?

Answer 65

A. What nerve is effected by this lesion? Facial nerve proper

B. Will this lesion effect general sensation of the head (if so which part) or

motor function to the head (if so which part)? BM mm facial exp

C. Will taste be effected by this lesion? Why or why not? No

D. Will this patient have any trouble crying on the right side? Why or why not? No

E. Will parotid gland function be effected by this lesion? Why or why not? No

F. During the physical examination you conduct the pupillary reflex … what

do you expect to observe in your patient? Normal reflex

G. During the physical examination you conduct the corneal reflex … what do

you expect to observe in your patient? No reflex

Question 66

A summary of Cranial Nerves:

Answer 66

Question 67

Table summary of CNs

Answer 67

Question 68

A 55 year-old man takes a baby aspirin once daily for cardiovascular event prevention. In anticipation of surgery for wide local excision of a melanoma on his neck, his surgeon has asked him to discontinue his aspirin. Aspirin has a plasma half-life of approximately three hours; it impairs platelet aggregation by irreversibly acetylating a serine residue on cyclooxygenase and thus inhibiting thromboxane A2 synthesis in platelets. How far in advance of his surgery should the patient discontinue his aspirin in order to have return of platelet aggregation capacity?

Answer 68

This is an example of a drug that exerts its effect both allosterically and on an enzyme instead of a receptor.

The plasma elimination half-life and effect half-life of a drug are not necessarily the same. The duration of effect of a drug depends on both its pharmacokinetic and pharmacodynamic properties.

Because aspirin irreversibly inhibits cyclooxygenase, its effect half-life is much greater than its plasma half-life. The effect half-life of aspirin correlates more closely to platelet half-life.

Cessation of aspirin therapy 7-10 days should allow return of platelet function.

Question 69

The personal physician to a 49 year-old musician with disordered sleep decides to administer intravenous boluses of lorazepam along with a continuous infusion of propofol to help his client sleep. Lorazepam and propofol are both allosteric modulators that enhance the function of GABAA receptors. The patient develops respiratory depression and dies. What pharmacodynamic and pharmacokinetic factors could have contributed to this patient’s death?

Answer 69

Administration of multiple drugs that affect the same receptor may have complex results depending on the strength of the bonds, the location of binding, and the intrinsic activity of the drugs.

Drugs with low therapeutic indices like propofol have a narrow range between the effective and toxic or lethal concentrations.

Concentration-time relationships for a single bolus dose of a drug may not always be useful for designing continuous infusion dosing regimens.

Question 70

1. A physician is considering beta-blocker therapy for a 63 year-old man with coronary artery disease who also suffers from chronic obstructive lung disease. Beta-1 receptor blockade decreases heart rate and contractility. Beta-2 receptor stimulation causes bronchodilation. Which of the following might be the most appropriate therapy for this patient?

A. Administration of a non-selective beta blocker

B. Administration of a beta-1 selective beta blocker

C. Administration of a beta-2 selective beta blocker D. Avoidance of all beta blockers

Answer 70

B. Administration of a beta-1 selective beta blocker

Reducing heart rate and contractility and thus cardiac work are therapeutic goals in coronary artery disease management. This can be accomplished with beta-1 adrenergic receptor blockade.

This patient also suffers from chronic obstructive pulmonary disease likely from a long-standing smoking history. He may have a bronchospastic component to his disease, and may even use a bronchodilating agent that activates beta-2 receptors. Blocking beta-2 receptors with a non-specific beta blocking drug could worsen his pulmonary symptoms.

Question 71

Consider the figure below. Which of the following best describes curve B?

A. A partial agonist compared to Drug A
B. Administration of Drug A in the presence of an irreversible antagonist
C. Administration of Drug A in the presence of an allosteric antagonist
D. Administration of Drug A in the presence of a non-competitive antagonist E. All of the above

Answer 71

E. All of the above

Key Points

In this case curve B depicts a lower maximal response compared to curve A. The half-maximal response occurs at approximately the same concentration.

Administration of the same agonist in the presence of a non-competitive antagonist (irreversible or allosteric) could account for this concentration-effect relationship.

This shape of curve could also be seen if B were a partial agonist compared to A.

Question 72

A 42 year-old woman develops a pulmonary embolus and begins therapy with warfarin. Through drug monitoring and dosage adjustment, the patient is determined to require approximately two-thirds the dose of the average patient to maintain therapeutic drug levels; after that point, her therapeutic course is uneventful. Which of the following terms best describes this patient’s drug response to warfarin?

A. Hyperreactive

B. Hyporeactive

C. Idiosyncratic D. Tachyphylactic E. Tolerant

Answer 72

A. Hyperreactive

Key Points

This case of a patient who is hyperreactive compared to normal populations is a pharmacogenetic example of genetic contribution to differences in drug responses within the population.

This patient likely carries one of the VKORC1 or CYP2C9 polymorphisms that result in increased sensitivity to the anticoagulant effects of warfarin.

Question 73

A 25 year-old female presents to the clinic with maxillary tooth pain and tenderness to the skin of her upper lip. She also complains of purulent nasal discharge and congestion for the past 12 days. Identify the nerve most likely affected resulting in these symptoms.

CN V-1

CN V-2

CN V-3

CN VII

Answer 73

Question 74

The Five Paranasal Sinuses

Answer 74

Question 75

In addition to rhinorrhea and nasal congestion, the same patient also presents with watery eyes and anosmia. Identify the most likely reason the patient has “watery eyes” and “anosmia”.

Answer 75

Block the nasolacrimal duct and affect the CNI

Question 76

A 4 year old female presents to the clinic with pain and swelling behind her left ear. What structure is inflamed? How could a sinus infection be associated with this finding?

Answer 76

The Mastoid antrium and mastoid air cells could be inflamed, and this could be from a sinus infection that has traveled into the nasal cavity and then up the opening of the pharyngotympanic tube!

Question 77

Would these lesions affect taste, lingual sensation, or both:

• mandibular nerve
• chorda tympani nerve
• proximal lingual nerve
• distal lingual nerve

Answer 77

Mandibular nerve: Lingual sensation

Chroda tympani: Taste

Proximal lingual nerve: Lingual sensation

Distal lingual nerve: Both

Question 78

A 45-year-old woman presents with paralysis of muscles of facial expression on her right side with ipsilateral loss of taste on the anterior surface of her tongue.

Where do you suspect the lesion to be occurring?

Answer 78

Right internal acoustiic meatus

Question 79

The path of CN VII: Facial nerve proper

Answer 79

Question 80

The path of CN VII: chorda Tympani nerve

Answer 80

Question 81

The path of CN VII: Greater petrosal nerve

Answer 81

Question 82

A 45-year-old woman presents with paralysis of muscles of facial expression on her right side with ipsilateral loss of taste on the anterior surface of her tongue.

What additional findings may you suspect?

Answer 82

Dryness of eyes

Dry mucous membranes in nasal cavity/palate

Dry mouth

Hyperacusis

Question 83

45-year-old woman presents with paralysis of muscles of facial expression on her right side with ipsilateral loss of taste on the anterior surface of her tongue.

What additional findings would you suspect if a CN VII schwannoma in the internal

acoustic meatus is the cause of her

problems?

Answer 83

Hearing Loss

Vertigo (balance problems)

Question 84

Imaging of a 56-year-old man shows a tumor compressing the nerves traversing the right hypoglossal canal. Identify the symptom(s) from the following list that the patient could be presenting with as a result of this condition. Explain why.

Answer 84

Difficulty saying “La, La, La, La, La”

Tongue deviates to side upon protrusion

Question 85

A 44-year-old male presents with the following deviation of his tongue during a physical examination (see photo). Imaging reveals a tiny stroke in his brainstem.

Identify the most likely location for this lesion.

Answer 85

Right Side Medulla

Question 86

A 60 year old man suffers a stroke. Using a tongue blade, the left side of the patient’s palate is touched, which results in a gag reflex with the left side of the palate elevating more then the right, and the uvula deviates to the left.

What nerve is most likely affected by this stroke?

What muscle is most likely affected?

What level of the brainstem is most likely affected? L or R?

Answer 86

What nerve is most likely affected by this stroke? CN X (vagus n.)

What muscle is most likely affected? Levator veli palatini m.

What level of the brainstem is most likely affected? L or R? Right

general sensory innervation to palate:

CN V-2 (greater and lesser palatine nerves)

Question 87

Answer 87

Question 88

Damage of the lingual nerve before it is joined by the chorda tympani in the infratemporal fossa would most likely result in loss of:

a. general sensation to the anterior two thirds of the tongue
b. general sensation to the posterior one third of the tongue
c. secretion of the submandibular gland
d. taste sensation from the anterior two thirds of the tongue
e. taste sensation from the posterior one third of the tongue

Answer 88

A. general sensation to the anterior two thirds of the tongue

• Lingual nerve comes from CN V-3 and does general sensation for anterior 2/3 of tongue
• Chorda tympani (from CN VII) not affected since lesion is prior to joining, so taste and secretions from submandibular and sublingual glands are intact
• posterior 1/3 of tongue: taste and general sensation from CN IX

Question 89

A 52-year-old man with ankylosing spondylitis underwent bilateral stapedectomy as a result of progressive hearing loss. The procedure resulted in a substantial improvement in the patient’s hearing. However, the right chorda tympani nerve was injured during the surgery. Identify symptoms from the following list that the patient present with as a result of this injury. Explain why.

Answer 89

Xerostomia (dry mouth)

Ageusia (ant 2/3 tounge)

Question 90

The middle nasal concha is part of what bone?

a. Ethmoid bone
b. Maxilla
c. Palatine bone
d. Sphenoid bone
e. Vomer

Answer 90

Ethmoid bone

• superior and middle nasal conchae are part of ethmoid bone
• perpendicular plate also part of ethmoid bone and forms superior part of nasal septum
• vomer is its own bone and forms posteroinferior part of nasal septum
• inferior nasal concha is its own bone
• palatine bone is its own bone and forms the posterior part of hard palate

Question 91

A 23-year-old man comes to you complaining that he can’t stop crying, i.e. tears regularly run down the right side of his face. You suspect that one of the lacrimal ducts on the right side of the face is blocked. You look into an endoscope to see if the nasolacrimal duct is blocked. Into which part of the nasal cavity would you most likely look to see the opening of the duct?

a. Hiatus semilunaris
b. Inferior meatus
c. Middle meatus
d. Sphenoethmoidal recess
e. Superior meatus

Answer 91

Inferior Meatus

• nasolacrimal duct drains into inferior meatus
• hiatus semilunaris is in the middle meatus, where frontal sinus , anterior ethmoid air cells, and maxillary sinus drain
• superior meatus receives drainage from posterior ethmoid air cells
• sphenoethmoidal recess is superior to superior nasal concha and receives drainage from sphenoid sinuses

Question 92

A 38-year-old patient complained of acute dental pain. The attending dentist found penetrating dental caries (dental decay) affecting one of the mandibular molar teeth. Which nerve would the dentist need to anesthetize to work on that tooth?

Answer 92

The inferior Alveolar

• inferior alveolar is branch of CN V-3, which does general sensation to mandibular teeth
• lingual nerve: branch of V-3. general sensation to tongue.
• buccal nerve: branch of V-3. general sensation from skin of cheek and cheek’s oral mucosa (vs. buccal nerve branch from VII—motor to buccinator and other muscles of facial expression)
• mental nerve: branch of V-3, from inferior alveolar nerve. general sensation to chin skin and lower lip.
• nerve to mylohyoid: branch of V-3. motor to mylohyoid and anterior belly of digastric.

Question 93

The pharyngeal tonsils (aka adenoids) may become inflamed and in serious cases need to be removed. Where would the physician most likely look to find them during surgery?

Dorsal surface of the tongue

Pharyngeal recess

Piriform recess

Roof of the nasopharynx

Tonsillar fossa

Answer 93

Question 94

Answer 94

Question 95

Answer 95

Question 96

Answer 96

Question 97

Answer 97

Question 98

Innervation of the Larynx

Answer 98

Question 99

Answer 99

Question 100

Answer 100