1.
A 28‑year‑old biker received a hard blow to the side of his head. X‑ray revealed pooling of blood in his epidural space. The source of blood is MOST LIKELY a ruptured:
Correct Answer
A. Middle meningeal artery
Explanation
The correct answer is the middle meningeal artery. The middle meningeal artery is a branch of the maxillary artery and is located in the epidural space between the dura mater and the skull. A hard blow to the side of the head can cause a fracture of the skull, leading to injury to the middle meningeal artery and subsequent bleeding into the epidural space. This condition is known as an epidural hematoma.
2.
A 55‑year‑old woman presents to her doctor with slight ptosis (drooping) of her left upper eyelid and mydriasis (dilation of pupil). A diagnosis of ophthalmoplegia (inability to move the eye) is made. This ptosis is due to:
Correct Answer
E. Injury to the oculomotor nerve
Explanation
The correct answer is injury to the oculomotor nerve. The oculomotor nerve is responsible for innervating the levator palpebrae superioris muscle, which lifts the upper eyelid. Damage to this nerve can result in ptosis (drooping) of the eyelid. Additionally, the oculomotor nerve also innervates the sphincter pupillae muscle, which constricts the pupil. Damage to the oculomotor nerve can therefore also lead to mydriasis (dilation) of the pupil.
3.
A young boy is taken to the pediatrician because of a nose bleed. Examination of Little's area shows blood exuding from the major artery that supplies the nasal cavity, which is the:
Correct Answer
B. SpHenopalatine
Explanation
The correct answer is Sphenopalatine. The sphenopalatine artery is the major artery that supplies the nasal cavity. When there is a nosebleed, blood can exude from this artery in a region called Little's area.
4.
A 16‑year‑old male high school student, troubled with a bad case of acne, complains of severe headache and problems with movements of his eyes. It is noted that he also has a high fever and is sweating profusely. By the swelling of the tissues on the left side of his face from an infected pimple adjacent to the philtrum leading to the upper lip, you conclude, correctly, that an infection has spread retrograde from the area of the acute infection to the cavernous sinus by way of ...
Correct Answer
B. Ipsilateral (same side) facial vein into the opHthalmic veins.
Explanation
The correct answer is that the infection has spread retrograde from the area of the acute infection to the cavernous sinus by way of the ipsilateral (same side) facial vein into the ophthalmic veins. The symptoms described, such as severe headache, problems with eye movements, high fever, and sweating, are consistent with a cavernous sinus thrombosis. In this case, the infection from the infected pimple adjacent to the upper lip has spread through the facial vein and into the ophthalmic veins, eventually reaching the cavernous sinus.
5.
On examining a lateral X‑ray of the neck, one can usually identify the faint image of the hyoid bone at the level of the ...
Correct Answer
D. Third cervical vertebra
Explanation
On examining a lateral X-ray of the neck, one can usually identify the faint image of the hyoid bone at the level of the third cervical vertebra.
6.
As you examine the 14‑year‑old female patient from Portsmouth, you realize that the evidence on physical examination indicates clearly that she has a right‑sided Bell's palsy. Which of the following signs would lead you to this conclusion?
Correct Answer
C. She is unable to close her right eye tightly.
Explanation
The inability to close the right eye tightly is a sign of right-sided Bell's palsy. Bell's palsy is a condition that affects the facial nerve, causing weakness or paralysis of the muscles on one side of the face. In this case, the weakness in the facial muscles specifically affecting the eye indicates that the patient has right-sided Bell's palsy. The other signs mentioned in the options, such as difficulty chewing, lack of pain or temperature sense in the right cheek, constriction of the right pupil, and deviation of the tongue to the left, are not specific to Bell's palsy and do not necessarily indicate the involvement of the facial nerve.
7.
During a fight in a tavern in Roseau, the 45‑year‑old construction worker received a shallow stab wound at a point near the middle of the left posterior triangle of the neck from a broken Kubuli bottle. On physical examination, it is noted that the left shoulder is drooping lower than the right shoulder, and the superior angle of the left scapula juts out slightly. Strength in turning the head to the right or left appears symmetric. From these facts, what has been injured?
Correct Answer
E. The left spinal accessory nerve, inferior to the sternocleidomastoid muscle
Explanation
Based on the given information, the 45-year-old construction worker received a stab wound near the middle of the left posterior triangle of the neck. The physical examination reveals that the left shoulder is drooping lower than the right shoulder, and the superior angle of the left scapula juts out slightly. These findings suggest an injury to the left spinal accessory nerve, which innervates the trapezius muscle responsible for shoulder movement. The nerve is located inferior to the sternocleidomastoid muscle, making it the most likely explanation for the observed symptoms.
8.
After a tonsillectomy your 14‑year‑old female patient has persistent bleeding from the tonsillar bed. Blood flow is slow but constant. The source of the blood is:
Correct Answer
B. External palatine vein
Explanation
The persistent bleeding from the tonsillar bed after a tonsillectomy is most likely due to the external palatine vein. The external palatine vein is located in the area of the tonsils and is responsible for draining blood from this region. If there is damage or injury to this vein during the tonsillectomy procedure, it can result in slow but constant bleeding from the tonsillar bed. The other options listed (tonsillar branch of the facial artery, ascending palatine artery, superior thyroid vein, ascending pharyngeal artery) are not typically associated with bleeding from the tonsillar bed.
9.
Increased Cerebral Spinal Fluid pressure that compresses the contents of the optic nerve is MOST LIKELY to cause:
Correct Answer
A. Swelling of the optic disc or papilla
Explanation
Increased Cerebral Spinal Fluid (CSF) pressure can lead to swelling of the optic disc or papilla. The optic disc is the area where the optic nerve enters the eye, and it is responsible for transmitting visual information from the eye to the brain. When the CSF pressure is elevated, it can compress the contents of the optic nerve, including blood vessels, leading to impaired blood flow and swelling of the optic disc. This can result in symptoms such as blurred vision, visual field defects, and changes in color vision. Therefore, swelling of the optic disc or papilla is the most likely consequence of increased CSF pressure.
10.
The 60‑year‑old woman had been experiencing chronic lancinating pain (very sharp, acute pain) between her left lower eyelid and her left upper lip. A diagnosis of tic douloureux is made and the decision is made to inject the ganglion wherein the highly irritable cell bodies are located which are responsible for the pain. Into which foramen should the needle be directed to reach the ganglion?
Correct Answer
A. The left infraorbital foramen
Explanation
The correct answer is the left infraorbital foramen. The infraorbital foramen is located on the maxilla bone, just below the orbit (eye socket). It is the opening through which the infraorbital nerve passes, and this nerve provides sensory innervation to the area between the lower eyelid and upper lip. By injecting the ganglion through the left infraorbital foramen, the highly irritable cell bodies responsible for the pain can be targeted and relieved.
11.
The 29‑year‑old female patient exhibits gustatory sweating, several months after having her left parotid gland removed because of a benign tumor; that is, she sweats profusely from the ipsilateral (same side) of the face when she smells food that she enjoys, or even thinks of it. This problem...
Correct Answer
A. Results from growth of fibers from the auriculotemporal nerve into the
subcutaneous tissue in the area of the bed of the parotid gland.
Explanation
Gustatory sweating, also known as Frey syndrome, is a condition that occurs after surgery on the parotid gland. It is caused by the regrowth of nerve fibers from the auriculotemporal nerve into the subcutaneous tissue in the area where the parotid gland used to be. These regrown fibers become connected to the sweat glands instead of the salivary glands, leading to sweating on the affected side of the face when the patient smells or thinks about food. Cutting the vagus nerve or the involvement of adrenergic chemical mediators are not related to this condition. Bell's palsy is a different condition and not a side effect of gustatory sweating.
12.
The 3‑year‑old child's eyelids had become swollen shut within a day after the dog had bitten her in the posterior part of her scalp. You, examining this suffering baby in the Emergency Department of the Staten Island Hospital in New York on your first evening of night call, know that ...
Correct Answer
B. Bleeding, and possibly infection, have spread through the areolar layer of the scalp.
Explanation
The correct answer is that bleeding, and possibly infection, have spread through the areolar layer of the scalp. This is supported by the information given in the question, which states that the child's eyelids had become swollen shut within a day after the dog had bitten her in the posterior part of her scalp. The areolar layer of the scalp is a loose connective tissue layer that contains blood vessels and lymphatics, making it susceptible to bleeding and the spread of infection.
13.
A 62‑year‑old woman who was a passenger in a car involved in a multi‑vehicle accident suffered cuts and bruises on her face and a brain concussion when her head forcibly hit the inside door frame of the car. On neurological examination she was found to have no sensation over the posterior one‑third of her tongue and her gag response was absent. Cranial x‑ray revealed she had a fracture of the cranial base. The fracture went through what structure?
Correct Answer
D. Jugular foramen
Explanation
The fracture of the cranial base in this case is likely to have gone through the jugular foramen. This is supported by the patient's symptoms of no sensation over the posterior one-third of her tongue and absent gag response, which are consistent with damage to the glossopharyngeal nerve (CN IX) and vagus nerve (CN X) that pass through the jugular foramen.
14.
The orthopedic surgeon wanted to operate on the patient's hand without using general anesthesia. She recognized that she could inject anesthetic into the axillary connective tissue sheath containing the nerves of the upper limb and achieve a nice anesthetic condition of the hand, suitable for operation without causing the patient unnecessary pain or loss of consciousness. She knows she must exercise care, however, because paralysis of half of the diaphragm could occur if the anesthetic entered the space deep to the...
Correct Answer
A. Prevertebral fascia anterior to the anterior scalene muscle
Explanation
The orthopedic surgeon wants to inject anesthetic into the axillary connective tissue sheath to achieve anesthesia in the patient's hand. However, she must exercise caution because if the anesthetic enters the space deep to the prevertebral fascia anterior to the anterior scalene muscle, it could cause paralysis of half of the diaphragm. This is because the phrenic nerve, which innervates the diaphragm, runs in this space. Therefore, it is important for the surgeon to avoid injecting the anesthetic into this specific area to prevent potential complications.
15.
A 14‑year‑old girl with a bad case of acne complains of severe headache, fever, tingling and burning in the skin of the midface and loss of all voluntary movement of her right eye. Physical and ophthalmoscopic examinations reveal swollen eye and engorged retinal veins. The loss of function of the right extraocular eye muscles is due to involvement of which structures that pass through the cavernous sinus?
Correct Answer
C. CN III, CN IV and CN VI
Explanation
The involvement of CN III, CN IV, and CN VI can explain the loss of function of the right extraocular eye muscles. CN III (oculomotor nerve) innervates most of the extraocular muscles involved in eye movement, including the superior, inferior, and medial rectus muscles, as well as the inferior oblique muscle. CN IV (trochlear nerve) innervates the superior oblique muscle, which helps with downward and inward eye movement. CN VI (abducens nerve) innervates the lateral rectus muscle, which is responsible for outward eye movement. Therefore, the involvement of these three cranial nerves can result in the loss of voluntary movement of the right eye.
16.
A teenager is diagnosed with cavernous sinus thrombosis. Infected blood drains from the cavernous sinus directly into the:
Correct Answer
D. Superior and inferior petrosal sinuses
Explanation
Cavernous sinus thrombosis is a condition where a blood clot forms in the cavernous sinus, a large vein located at the base of the brain. The cavernous sinus receives blood from several veins, including the superior and inferior petrosal sinuses. Therefore, in this condition, infected blood would drain from the cavernous sinus directly into the superior and inferior petrosal sinuses.
17.
A 35‑year‑old woman suffers from maxillary sinusitis. Pus generated in the maxillary sinus is MOST LIKELY to drain into what part of the nasal cavity?
Correct Answer
D. Middle meatus
Explanation
Pus generated in the maxillary sinus is most likely to drain into the middle meatus of the nasal cavity. The middle meatus is located between the inferior and middle nasal conchae, and it is the area where the openings of the maxillary sinus, frontal sinus, and anterior ethmoid air cells are located. Since the maxillary sinus is located in close proximity to the middle meatus, it is the most likely pathway for the pus to drain out of the sinus and into the nasal cavity.
18.
A 45‑year‑old man visits his doctor because of ringing in his left ear. Physical examination reveals an infection of the middle ear. If the infection spreads into the facial canal located in the medial wall of the tympanic cavity, which of the following signs and symptoms is LEAST LIKELY to occur?
Correct Answer
A. Vertigo (dizziness)
Explanation
If the infection spreads into the facial canal, it is least likely to cause vertigo (dizziness). Vertigo is commonly associated with inner ear problems, such as labyrinthitis or vestibular neuritis, rather than middle ear infections. The infection in the facial canal may affect the facial nerve, leading to symptoms like loss of lacrimation, reduced salivation, and loss of taste from the tip of the tongue. However, vertigo is not typically associated with this specific complication. Sounds being annoyingly loud could be a possible symptom due to the involvement of the facial nerve.
19.
The 22‑year‑old woman is to undergo bilateral (both sides) removal of the C6 ‑ T2 segments of her sympathetic chains, in an attempt to correct the excessive, chronic vasoconstriction in her upper limbs that was causing ischemia (loss of adequate blood supply) to her hands, especially in her fingers. You must caution her that this procedure will result in ...
Correct Answer
A. A slight drooping of her upper eyelids (partial ptosis).
Explanation
The sympathetic chains are part of the autonomic nervous system that control involuntary functions, including blood vessel constriction. By removing segments of the sympathetic chains, the excessive vasoconstriction in the woman's upper limbs can be corrected. However, the sympathetic chains also play a role in controlling the muscles that elevate the upper eyelids. Therefore, the removal of these segments may result in a slight drooping of the upper eyelids, known as partial ptosis.
20.
The parasympathetic portion of the Autonomic Nervous System acts to maintain homeostasis, insuring the normal functions of processes vital to life. With regard to this system, it is well known that ...
Correct Answer
A. Parasympathetic stimulation of the heart results in a negative chronotropic effect in cardiac activity.
Explanation
The parasympathetic stimulation of the heart results in a negative chronotropic effect in cardiac activity. This means that when the parasympathetic portion of the Autonomic Nervous System is activated, it slows down the heart rate. This is important for maintaining homeostasis and ensuring normal functioning of the cardiovascular system.
21.
A 22‑year‑old male comes into your office complaining of hoarseness and an unsettling inability to change the tone of his voice normally. He has never smoked and he drinks alcohol in moderation. He is of normal weight and has no nasal, oral, or pharyngeal obstructions. When you examine him with the laryngoscope you note that the laryngopharyngeal mucosa is normal, all movements of the arytenoid cartilages seem normal, and the vocal folds are free of inflammation and polyps. You do notice an asymmetrical dislocation of the rima glottidis to the left when the patient attempts to speak in a higher tone of voice, indicating that the forward rotation of the thyroid cartilage is weakened. The only noteworthy point of the patient's history is that he is a kick boxer and sustained a blow to the right side of his throat the night before he noted the alterations in his voice. Damage to which nerve is responsible for his symptoms?
Correct Answer
C. External laryngeal nerve
Explanation
The external laryngeal nerve is responsible for innervating the cricothyroid muscle, which is responsible for adjusting the tension of the vocal folds and changing the pitch of the voice. In this case, the patient's inability to change the tone of his voice normally and the asymmetrical dislocation of the rima glottidis to the left when attempting to speak in a higher tone indicate weakened forward rotation of the thyroid cartilage. This suggests damage to the external laryngeal nerve, which would result in the inability to properly adjust the tension of the vocal folds and change the pitch of the voice.