Head & Neck

Head & Neck US Medical PG Question 1: A 28-year-old man is admitted to the hospital for the evaluation of symmetric, ascending weakness that started in his feet and has become progressively worse over the past 5 days. A lumbar puncture is performed to confirm the diagnosis. As the needle is advanced during the procedure, there is resistance just before entering the epidural space. This resistance is most likely due to which of the following structures?

• A. Dura mater
• B. Supraspinous ligament
• C. Interspinous ligament
• D. Ligamentum flavum (Correct Answer)
• E. Superficial fascia

Head & Neck Explanation: ***Ligamentum flavum*** - The **ligamentum flavum** is encountered after the interspinous ligament and is the last major ligament traversed before entering the **epidural space**. - It is a **thick, elastic, and strong ligament** that provides significant resistance to the needle, often described as a "pop" or "give" sensation as it is penetrated. *Dura mater* - The **dura mater** is the outermost membrane of the meninges and is encountered *after* the epidural space, surrounding the spinal cord. - While it provides some resistance, the more significant resistance *just before* the epidural space is due to the ligamentum flavum. *Supraspinous ligament* - The **supraspinous ligament** is a strong fibrous cord that connects the tips of the spinous processes. - It is located more superficially and is therefore encountered much earlier in the lumbar puncture procedure, not just before the epidural space. *Interspinous ligament* - The **interspinous ligament** connects adjacent spinous processes and is traversed *before* the ligamentum flavum. - It offers some resistance, but it is typically less prominent than the resistance felt when penetrating the thicker ligamentum flavum. *Superficial fascia* - The **superficial fascia** is located immediately beneath the skin and subcutaneous tissue. - It is encountered very early in the procedure and would not be the structure providing resistance just before the epidural space.

Head & Neck US Medical PG Question 2: A 65-year-old male presents to the emergency room complaining of a severe headache. He developed a sudden-onset severe throbbing headache while watching a football game on television. His past medical history is significant for migraines and hypertension; however, he states that this headache is different from his normal migraine headaches. He has a 30 pack-year smoking history. His family history is notable for stroke in his mother and father. His temperature is 98.9°F (37.2°C), blood pressure is 150/90 mmHg, pulse is 100/min, and respirations are 14/min. On examination, he is oriented to person, place, and time. Neck motion is limited due to pain. Strength is 5/5 bilaterally in both the upper and the lower extremities and sensation is grossly intact across all the dermatomal distributions. Patellar, brachioradialis, and Achilles reflexes are 2+ bilaterally. The vessel that is most commonly involved in this patient's likely condition directly branches off which of the following vessels?

• A. Middle cerebral artery
• B. Maxillary artery
• C. Anterior cerebral artery
• D. Posterior cerebral artery
• E. Internal carotid artery (Correct Answer)

Head & Neck Explanation: ***Internal carotid artery*** - The patient's presentation with a **sudden-onset, severe "thunderclap" headache**, cervical pain, and normal neurologic examination, particularly in the context of **hypertension and smoking history**, is highly suggestive of a **subarachnoid hemorrhage (SAH)**. SAH is most commonly caused by rupture of a **saccular (berry) aneurysm**. - Approximately 85% of SAHs result from the rupture of an aneurysm in the **anterior circulation**. The most common site for these aneurysms is the **anterior communicating artery**, which directly branches off the **anterior cerebral artery**. However, the **anterior cerebral artery (ACA)**, the **middle cerebral artery (MCA)**, and the **posterior communicating artery (PCoA)** (which is commonly involved in berry aneurysms) all originate directly or indirectly, through the ACA, from the **internal carotid artery (ICA)**. Therefore, the ICA is the most encompassing and correct option from which the most common aneurysm sites ultimately branch. *Middle cerebral artery* - While the **middle cerebral artery (MCA)** is a common location for aneurysms, particularly at its bifurcation, it is generally less common than the anterior communicating artery or the posterior communicating artery. - Aneurysms of the MCA are also branches of the internal carotid artery. *Maxillary artery* - The **maxillary artery** is primarily involved in supplying blood to structures in the deep face, maxilla, and mandible. - It is not a significant location for intracranial berry aneurysms that lead to subarachnoid hemorrhage. *Anterior cerebral artery* - While the **anterior cerebral artery (ACA)** itself can be a site for aneurysms, particularly the **anterior communicating artery** (AComA) which connects the two ACAs, it is a branch off the internal carotid artery. - The AComA is the single most common site for berry aneurysms; however, the question asks for the vessel from which the commonly involved vessel *directly branches off*. The ACA itself directly branches off the ICA. *Posterior cerebral artery* - The **posterior cerebral artery (PCA)** is part of the posterior circulation, originating from the basilar artery. - Aneurysms in the posterior circulation (vertebrobasilar system) are less common causes of SAH than those in the anterior circulation.

Head & Neck US Medical PG Question 3: A 60-year-old male is admitted to the ICU for severe hypertension complicated by a headache. The patient has a past medical history of insulin-controlled diabetes, hypertension, and hyperlipidemia. He smokes 2 packs of cigarettes per day. He states that he forgot to take his medications yesterday and started getting a headache about one hour ago. His vitals on admission are the following: blood pressure of 160/110 mmHg, pulse 95/min, temperature 98.6 deg F (37.2 deg C), and respirations 20/min. On exam, the patient has an audible abdominal bruit. After administration of antihypertensive medications, the patient has a blood pressure of 178/120 mmHg. The patient reports his headache has increased to a 10/10 pain level, that he has trouble seeing, and he can't move his extremities. After stabilizing the patient, what is the best next step to diagnose the patient's condition?

• A. Doppler ultrasound of the carotids
• B. CT head with intravenous contrast
• C. MRI head without intravenous contrast
• D. CT head without intravenous contrast (Correct Answer)
• E. MRI head with intravenous contrast

Head & Neck Explanation: ***CT head without intravenous contrast*** - The sudden onset of severe headache, visual disturbances, and neurological deficits (inability to move extremities), coupled with uncontrolled severe hypertension despite initial treatment, is highly suggestive of an **intracranial pathology**, most likely a **hemorrhagic stroke**. - A **non-contrast CT scan of the head** is the **gold standard** for rapidly identifying acute intracranial hemorrhage, as it can be performed quickly and is readily available in emergency settings. *Doppler ultrasound of the carotids* - This test is primarily used to evaluate **carotid artery stenosis** due to atherosclerosis, which can lead to ischemic stroke. - While the patient has risk factors for atherosclerosis, his acute presentation with severe central neurological symptoms points more towards an acute intracranial event rather than carotid disease. *CT head with intravenous contrast* - While a contrast CT can be useful for identifying tumors, abscesses, or vascular malformations, it is **contraindicated in the initial assessment of acute stroke** if an intracranial hemorrhage is suspected. - Contrast can sometimes obscure subtle bleeds or complicate the interpretation of acute hemorrhage, and it also carries a risk of **contrast-induced nephropathy**, especially in a patient with diabetes. *MRI head without intravenous contrast* - An MRI provides superior soft tissue resolution compared to CT and is excellent for detecting ischemic strokes in later stages, as well as subtle hemorrhages, tumors, and other conditions. - However, it is **less available, takes longer to perform**, and is often not the first choice in an acute neurological emergency where time is critical, particularly when differentiating between ischemic and hemorrhagic stroke. *MRI head with intravenous contrast* - Similar to a contrast CT, an MRI with contrast is generally **not the initial imaging choice for acute stroke** due to time constraints and the need to quickly rule out hemorrhage before considering contrast administration. - Contrast agents for MRI, such as gadolinium, have their own risks, including **nephrogenic systemic fibrosis** in patients with renal impairment, which is a concern in a diabetic patient.

Head & Neck US Medical PG Question 4: A 16-year-old girl presents with a sore throat. The patient says symptoms onset acutely 3 days ago and have progressively worsened. She denies any history of cough, nasal congestion or rhinorrhea. No significant past medical history or current medications. The vital signs include: temperature 37.7°C (99.9°F), blood pressure 110/70 mm Hg, pulse 74/min, respiratory rate 20/min, and oxygen saturation 99% on room air. Physical examination is significant for anterior cervical lymphadenopathy. There is edema of the oropharynx and tonsillar swelling but no tonsillar exudate. Which of the following is the next best step in management?

• A. Reassurance
• B. Empiric treatment with antibiotics
• C. Empiric treatment with antivirals
• D. Rapid strep test (Correct Answer)
• E. Ultrasound of the anterior cervical lymph nodes

Head & Neck Explanation: ***Rapid strep test*** - This patient presents with symptoms suggestive of **Streptococcal pharyngitis (Centor criteria)**, including acute onset sore throat, anterior cervical lymphadenopathy, tonsillar swelling, and absence of cough. A rapid strep test is crucial to confirm the diagnosis and guide antibiotic therapy. - While tonsillar exudates are often present in strep throat, their absence does not rule out the diagnosis, especially given the other strong indicators. *Reassurance* - Reassurance alone is insufficient given the patient's symptoms are highly suggestive of a **bacterial infection** that could lead to serious complications if left untreated. - Untreated **Streptococcal pharyngitis** can lead to complications such as acute rheumatic fever and peritonsillar abscess. *Empiric treatment with antibiotics* - Empiric antibiotic treatment without confirmation can contribute to **antibiotic resistance** and is not the best approach when a diagnostic test is readily available. - Without a positive rapid strep test, the patient could be unnecessarily exposed to antibiotics, potentially leading to **adverse drug reactions** or masking other underlying conditions. *Empiric treatment with antivirals* - The patient's symptoms are more consistent with a **bacterial infection** (strep throat) rather than a viral illness that would benefit from antiviral treatment. - Antivirals are generally reserved for specific viral infections like influenza or herpes, and there is no indication for their use in this clinical scenario. *Ultrasound of the anterior cervical lymph nodes* - While the patient has **anterior cervical lymphadenopathy**, this is a common finding in pharyngitis and an ultrasound is not necessary as a first step to diagnose the cause of a sore throat. - Imaging of the lymph nodes would be considered if there were concerns for an **abscess** or malignancy, which are not suggested by the current presentation.

Head & Neck US Medical PG Question 5: A 45-year-old patient presents with difficulty speaking and swallowing following a stroke. MRI reveals an infarct in the medulla. Which of the following cranial nerve nuclei is most likely affected?

• A. Vestibulocochlear nucleus
• B. Trigeminal nerve nucleus
• C. Facial nerve nucleus
• D. Nucleus ambiguus (Correct Answer)

Head & Neck Explanation: ***Nucleus ambiguus*** - The **nucleus ambiguus** is located in the **medulla** and contains motor neurons that innervate muscles involved in **speaking** and **swallowing**, specifically those of the pharynx, larynx, and soft palate via cranial nerves IX, X, and XI. - An infarct in the medulla causing difficulty speaking and swallowing strongly implicates damage to this nucleus, leading to **dysarthria** and **dysphagia**. *Vestibulocochlear nucleus* - This nucleus is primarily involved in **hearing** and **balance**, which would manifest as dizziness, hearing loss, or nystagmus, not directly difficulty speaking and swallowing. - While located in the brainstem, damage to this nucleus typically does not cause the specific symptoms of dysarthria and dysphagia described. *Trigeminal nerve nucleus* - The trigeminal nerve is responsible for sensory innervation of the face, and motor innervation for **mastication** (chewing). - Damage would primarily affect facial sensation or jaw movement, not the act of deglutition or phonation. *Facial nerve nucleus* - This nucleus, located in the **pons**, controls the muscles of **facial expression** and taste for the anterior two-thirds of the tongue. - Damage would lead to facial weakness or paralysis, not the profound difficulty with speaking and swallowing affecting pharyngeal and laryngeal function.

Head & Neck US Medical PG Question 6: A 78-year-old man is brought in to the emergency department by ambulance after his wife noticed that he began slurring his speech and had developed facial asymmetry during dinner approximately 30 minutes ago. His past medical history is remarkable for hypertension and diabetes. His temperature is 99.1°F (37.3°C), blood pressure is 154/99 mmHg, pulse is 89/min, respirations are 12/min, and oxygen saturation is 98% on room air. Neurologic exam reveals right upper and lower extremity weakness and an asymmetric smile. Which of the following is the next best step in management?

• A. Alteplase
• B. MRI brain
• C. CT head (Correct Answer)
• D. Aspirin
• E. CTA head

Head & Neck Explanation: ***CT head*** - A **non-contrast CT head** is the immediate priority to differentiate between ischemic and hemorrhagic stroke, which is critical for guiding subsequent treatment decisions. - Given the patient's acute neurological deficits (slurred speech, facial asymmetry, weakness) and vascular risk factors (hypertension, diabetes), **stroke is highly suspected**, and identifying intracerebral hemorrhage is crucial before considering thrombolytic therapy. *Alteplase* - **Alteplase** (tPA) is a thrombolytic agent used for acute ischemic stroke, but its administration is **contraindicated in hemorrhagic stroke**. - Initiating alteplase without first ruling out hemorrhage with a CT scan could lead to catastrophic bleeding. *MRI brain* - While an **MRI brain** can provide more detailed imaging of stroke, it is typically **not the initial imaging modality** in the emergency setting due to longer acquisition times and limited availability, especially when emergent differentiation between ischemic and hemorrhagic stroke is needed. - Its use is usually reserved for cases where the CT is inconclusive or for later evaluation. *Aspirin* - **Aspirin** is an antiplatelet agent used in the management of ischemic stroke, but it should **not be given until a hemorrhagic stroke has been ruled out** via CT head. - Administering aspirin in the context of an intracerebral hemorrhage could worsen bleeding. *CTA head* - A **CT angiography (CTA) head** is used to visualize the cerebral vasculature and identify large vessel occlusions, which can guide thrombectomy decisions in ischemic stroke. - However, performing a **non-contrast CT head is a prerequisite** to rule out hemorrhage before proceeding with CTA or any other advanced imaging or therapeutic interventions.

Head & Neck US Medical PG Question 7: A 72-year-old woman is brought in to the emergency department after her husband noticed that she appeared to be choking on her dinner. He performed a Heimlich maneuver but was concerned that she may have aspirated something. The patient reports a lack of pain and temperature on the right half of her face, as well as the same lack of sensation on the left side of her body. She also states that she has been feeling "unsteady" on her feet. On physical exam you note a slight ptosis on the right side. She is sent for an emergent head CT. Where is the most likely location of the neurological lesion?

• A. Pons
• B. Internal capsule
• C. Cervical spinal cord
• D. Medulla (Correct Answer)
• E. Midbrain

Head & Neck Explanation: ***Medulla*** - This presentation describes **Wallenberg syndrome** (lateral medullary syndrome), characterized by **ipsilateral facial sensory loss**, **contralateral body sensory loss**, and **ataxia** due to involvement of the spinothalamic tracts, trigeminal nucleus, and cerebellar pathways. - **Dysphagia** (choking) and **Horner's syndrome** (ptosis, miosis, anhidrosis) are also classic signs, specifically the ptosis seen here, pointing to an infarct in the **lateral medulla**. *Pons* - Lesions in the pons typically present with varying degrees of **cranial nerve deficits** (e.g., trigeminal, abducens, facial) and **motor or sensory deficits** affecting both sides of the body due to the decussation of tracts. - The specific combination of **crossed sensory loss** and other symptoms seen here is not characteristic of isolated pontine lesions. *Internal capsule* - A lesion in the internal capsule would primarily cause **contralateral motor weakness (hemiparesis)** and **sensory loss** affecting both the face and body on the same side, without the ipsilateral facial involvement. - It would not explain the **ataxia** or specific cranial nerve signs like ptosis. *Cervical spinal cord* - Spinal cord lesions result in **sensory and motor deficits below the level of the lesion**, affecting both sides of the body symmetrically, or ipsilaterally depending on the tract involved. - They do not cause **facial sensory disturbances**, **dysphagia**, or **ataxia** in the manner described. *Midbrain* - Midbrain lesions typically involve the **oculomotor nerve** (CN III), causing eye movement abnormalities, and can result in **contralateral hemiparesis**. - They do not produce the **crossed sensory deficits** (ipsilateral face, contralateral body) or **ataxia** characteristic of this case.

Head & Neck US Medical PG Question 8: During a surgical procedure involving the posterior triangle of the neck, which of the following muscles forms its anterior boundary?

• A. Scalene anterior
• B. Trapezius
• C. Sternocleidomastoid (Correct Answer)
• D. Omohyoid

Head & Neck Explanation: ***Sternocleidomastoid*** - The **sternocleidomastoid muscle** forms the **anterior boundary** of the **posterior triangle of the neck**. - Its broad origin on the sternum and clavicle and insertion on the mastoid process help define this triangular region. *Scalene anterior* - The **scalene anterior muscle** is located deeper in the neck and is not a direct boundary of the posterior triangle. - This muscle is part of the **floor** of the posterior triangle, along with other prevertebral muscles, but does not form its anterior border. *Trapezius* - The **trapezius muscle** forms the **posterior boundary** of the posterior triangle of the neck, running from the nuchal line and thoracic vertebrae to the clavicle and scapula. - It would be incorrect to identify it as the anterior boundary. *Omohyoid* - The **inferior belly of the omohyoid muscle** crosses the posterior triangle, subdividing it into occipital and supraclavicular triangles. - It does not form one of the main borders of the entire posterior triangle.

Head & Neck US Medical PG Question 9: A 26-year-old man is brought to the emergency department by ambulance after being involved in a motor vehicle collision. He does not open his eyes on command or respond to verbal cues. A CT scan of the head shows a hyperdense fluid collection in the right medial temporal lobe with medial displacement of the uncus and parahippocampal gyrus of the temporal lobe. Which of the following cranial nerves is most likely to be injured as a result of this patient's lesion?

• A. Vagus
• B. Facial
• C. Oculomotor (Correct Answer)
• D. Abducens
• E. Trigeminal

Head & Neck Explanation: ***Oculomotor*** - The description of **medial displacement of the uncus and parahippocampal gyrus** (uncus herniation) compresses the **oculomotor nerve (CN III)** as it passes between the posterior cerebral and superior cerebellar arteries. - Compression of the oculomotor nerve leads to a **dilated pupil** (due to parasympathetic fiber involvement) and **down-and-out deviation of the eye** (due to paralysis of extraocular muscles it innervates). *Vagus* - The vagus nerve (CN X) is deep within the skull and brainstem, far from the temporal lobe, and is not directly affected by uncal herniation. - Injury to the vagus nerve typically presents with dysphagia, hoarseness, or cardiac arrhythmias, symptoms not indicated here. *Facial* - The facial nerve (CN VII) exits the brainstem at the pontomedullary junction and is located more superiorly and laterally than the structures involved in uncal herniation. - Damage to the facial nerve causes facial muscle weakness or paralysis, which is not the primary concern with uncal herniation. *Abducens* - The abducens nerve (CN VI) is a long, slender nerve that can be affected by **generalized increases in intracranial pressure**, but is less commonly directly compressed by an uncal herniation itself. - Injury to the abducens nerve causes **lateral rectus muscle paralysis**, leading to medial deviation of the eye, whereas uncal herniation typically affects the oculomotor nerve. *Trigeminal* - The trigeminal nerve (CN V) exits the pons and is located superior to the tentorial notch and medial temporal lobe, making it unlikely to be directly compressed by uncal herniation. - Injury to the trigeminal nerve causes sensory loss in the face or weakness of the muscles of mastication, which are not consistent with the described lesion.

Head & Neck US Medical PG Question 10: An 87-year-old male presents to his neurologist for a follow-up visit. He is being followed for an inoperable tumor near his skull. He reports that he recently noticed that food has started to lose its taste. He also notes increasing difficulty with swallowing. He has a history of myocardial infarction, diabetes mellitus, hyperlipidemia, hypertension, and presbycusis. He takes aspirin, metoprolol, metformin, glyburide, atorvastatin, lisinopril, and hydrochlorothiazide. On examination, the patient is a frail-appearing male sitting in a wheelchair. He is oriented to person, place, and time. Gag reflex is absent on the right side. A taste evaluation is performed which demonstrates a decreased ability to detect sour and bitter substances on the right posterior tongue. The nerve responsible for this patient’s loss of taste sensation also has which of the following functions?

• A. Somatic sensory innervation to the roof of the pharynx
• B. Parasympathetic innervation to the trachea
• C. Somatic sensory innervation to the lower lip
• D. Parasympathetic innervation to the parotid gland (Correct Answer)
• E. Parasympathetic innervation to the submandibular gland

Head & Neck Explanation: ***Parasympathetic innervation to the parotid gland*** - The patient's symptoms, including loss of taste on the **right posterior tongue**, difficulty swallowing, and an absent gag reflex, point to an issue with the **glossopharyngeal nerve (CN IX)**. - The glossopharyngeal nerve provides **parasympathetic innervation to the parotid gland** via the otic ganglion, stimulating saliva production. *Somatic sensory innervation to the roof of the pharynx* - The glossopharyngeal nerve (CN IX) does provide somatic sensory innervation to the pharynx, but specifically the **posterior 1/3 of the tongue**, tonsils, and part of the pharynx, not primarily the roof. - While related to the pharynx, this option is not the most precise or unique function associated with the primary nerve implicated here. *Parasympathetic innervation to the trachea* - **Parasympathetic innervation to the trachea** is primarily mediated by the **vagus nerve (CN X)**, which innervates the smooth muscle and glands of the trachea and bronchi. - The glossopharyngeal nerve (CN IX) does not have a direct role in tracheal innervation. *Somatic sensory innervation to the lower lip* - **Somatic sensory innervation to the lower lip** is primarily provided by the **mental nerve**, a branch of the **trigeminal nerve (CN V)**. - The glossopharyngeal nerve (CN IX) is not involved in sensory innervation of the lower lip. *Parasympathetic innervation to the submandibular gland* - **Parasympathetic innervation to the submandibular and sublingual glands** is provided by the **facial nerve (CN VII)** via the submandibular ganglion. - This function is distinct from the glossopharyngeal nerve's role in innervating the parotid gland.

Head & Neck Flashcard 1 of 10

Question: Which lymph node cluster drains the head and neck? _____

Answer: Cervical

Head & Neck Flashcard 2 of 10

Question: The middle meningeal artery is a branch of the _____ artery

Answer: maxillary

Head & Neck Flashcard 3 of 10

Question: Thyroid papillary carcinoma often spreads to the _____ nodes (lymphatic invasion)

Answer: cervical

Head & Neck Flashcard 4 of 10

Question: ID Chamber: _____

Answer: Posterior chamber

Head & Neck Flashcard 5 of 10

Question: Nasopharyngeal carcinoma often presents with involvement of _____ lymph nodes

Answer: cervical

Head & Neck Flashcard 6 of 10

Question: Horner syndrome presents with ptosis due to denervation of the _____ muscle

Answer: superior tarsal

Head & Neck Flashcard 7 of 10

Question: Light reflex: The ciliary ganglia send post-ganglionic parasympathetic neurons to the pupillary constrictor muscle via _____ nerves

Answer: short ciliary

Head & Neck Flashcard 8 of 10

Question: What lymph node cluster drains the nasal cavity, nasopharynx, and auditory tubes?_____

Answer: Retropharyngeal lymph nodes

Head & Neck Flashcard 9 of 10

Question: CN 9

Answer:

Head & Neck Flashcard 10 of 10

Question: parafollicular cells (C-cells) of thyroid

Answer: neural crest