Chapter: Head & Neck — Larynx
Topic: Lymphatic Drainage of the Larynx
Subtopic: Subglottic (below vocal cords) drainage & clinical relevance
Keyword Definitions:
Larynx: Organ of voice and airway protection, divided into supraglottis, glottis, and subglottis.
Subglottis: Region of larynx below the vocal cords extending to the inferior border of cricoid cartilage.
Pretracheal lymph nodes: Lymph nodes anterior to trachea receiving drainage from lower larynx and trachea.
Paratracheal nodes: Nodes alongside trachea that communicate with superior mediastinal nodes.
Clinical significance: Pattern of lymphatic drainage determines sites of metastasis in laryngeal cancer and guides neck dissection and radiotherapy planning.
1) Lead Question – 2016
Larynx below the vocal cords drain into ?
a) Pretracheal lymph nodes
b) Occipital lymphnodes
c) Mediastinal nodes
d) Lymphatics along the superior laryngeal vein
Answer: a) Pretracheal lymph nodes
Explanation: The subglottic region (below the vocal cords) drains primarily to the pretracheal and paratracheal lymph nodes which lie anterior and lateral to the trachea; these nodes then communicate inferiorly with the superior mediastinal nodes. This drainage pattern contrasts with the supraglottis (which drains to upper deep cervical nodes) and the glottis (which has limited lymphatics). Clinically, tumors arising in the subglottic larynx more readily involve pretracheal/paratracheal nodes and may present with lower cervical or mediastinal metastases. Knowledge of this pathway guides neck dissection planning and radiotherapy fields in laryngeal cancer management.
2) The supraglottic larynx primarily drains to which nodes?
a) Submental nodes
b) Upper deep cervical (jugulodigastric) nodes
c) Pretracheal nodes
d) Occipital nodes
Answer: b) Upper deep cervical (jugulodigastric) nodes
Explanation: The supraglottic larynx — including the epiglottis, aryepiglottic folds, and false cords — has an abundant lymphatic plexus that drains principally to the upper deep cervical nodes, especially the jugulodigastric node. This explains why supraglottic cancers frequently present with cervical lymphadenopathy; early nodal metastasis is common and often occult. Surgical and radiotherapeutic strategies therefore target the upper jugular chains when supraglottic malignancy is present. Recognizing this drainage pattern is crucial for staging, prognostication, and planning therapeutic neck dissections or radiation target volumes.
3) The vocal cords (true cords) have relatively sparse lymphatics. Which statement is true?
a) True vocal cord tumors commonly metastasize early
b) Glottic cancers are frequently associated with nodal metastasis at presentation
c) Early glottic cancers rarely involve cervical lymph nodes
d) Glottic lymph drains to occipital nodes
Answer: c) Early glottic cancers rarely involve cervical lymph nodes
Explanation: The true vocal cords (glottis) have few lymphatic channels, particularly in their mid-portion, so early-stage glottic cancers (T1–T2) seldom metastasize to cervical lymph nodes. This contrasts with supraglottic lesions. Consequently, early glottic cancer can often be treated with local radiotherapy or limited surgery without elective neck dissection. However, lesions involving the anterior/posterior commissure or extending to supraglottic/subglottic areas may have higher nodal risk. Understanding this anatomic fact underpins clinical decision-making about elective neck treatment in laryngeal carcinoma.
4) Which nodes receive drainage directly from the hypopharynx and lower larynx and are thus important in spread of subglottic cancer?
a) Deep lateral cervical (levels II–IV)
b) Suboccipital nodes
c) Preauricular nodes
d) Superficial cervical nodes
Answer: a) Deep lateral cervical (levels II–IV)
Explanation: Although the subglottic region first drains to pretracheal/paratracheal nodes, subsequent spread commonly involves the deep lateral cervical chain (levels II–IV), which are critical pathways for metastatic dissemination of hypopharyngeal and lower laryngeal cancers. Clinicians evaluating neck metastases focus on these deep nodes; imaging and surgical dissections target levels II–IV when metastasis is suspected. Knowledge of these nodal basins is essential for accurate staging, choosing the extent of neck dissection, and tailoring radiotherapy fields to encompass likely sites of microscopic disease.
5) Clinically, involvement of pretracheal/paratracheal nodes by subglottic carcinoma most likely mandates consideration of which additional therapy approach?
a) Elective orchiectomy
b) Inclusion of superior mediastinal nodes in radiotherapy fields
c) Excision of parotid gland
d) Occipital node dissection
Answer: b) Inclusion of superior mediastinal nodes in radiotherapy fields
Explanation: Because pretracheal/paratracheal nodes communicate with the superior mediastinal nodal basin, documented involvement of these stations in subglottic cancer may warrant extending radiation fields inferiorly to cover superior mediastinal nodes or even performing targeted surgical sampling in appropriate cases. Treatment planning must account for the anatomic drainage pathway to reduce the risk of residual disease. This consideration is especially relevant for advanced tumors with suspicious lower cervical or mediastinal nodal disease on imaging.
6) In laryngeal cancer staging, cervical lymph node metastasis most strongly affects prognosis. Which laryngeal subsite carries the highest risk of nodal spread?
a) Glottis
b) Supraglottis
c) Subglottis
d) Epiglottis only
Answer: b) Supraglottis
Explanation: The supraglottic larynx has an extensive lymphatic network draining bilaterally to the upper deep cervical nodes, predisposing tumors in this subsite to early and frequent cervical metastases. Consequently, supraglottic carcinomas often have worse nodal-related prognosis compared with early glottic tumors. This higher propensity for nodal spread influences both staging and treatment: clinicians commonly perform elective neck dissection or include bilateral neck irradiation for supraglottic malignancies even when clinically node-negative.
7) Which nerve provides sensory innervation above the vocal cords (important for laryngeal reflexes and tumor symptomatology)?
a) Superior laryngeal branch of vagus (internal branch)
b) Recurrent laryngeal nerve
c) Glossopharyngeal nerve only
d) Hypoglossal nerve
Answer: a) Superior laryngeal branch of vagus (internal branch)
Explanation: The internal branch of the superior laryngeal nerve (from the vagus via the superior laryngeal) supplies sensory innervation to the mucosa of the supraglottis down to the level of the vocal cords. This afferent input mediates protective laryngeal reflexes and contributes to symptoms such as foreign body sensation or pain when supraglottic tumors are present. Recurrent laryngeal nerve supplies motor function to intrinsic laryngeal muscles (except cricothyroid) and sensory below the vocal cords; these distinctions are important for surgical planning and understanding presenting deficits in laryngeal disease.
8) A patient with subglottic carcinoma develops a metastatic node at the root of the neck and superior mediastinum on imaging. Which statement best describes the likely pathway?
a) Direct hematogenous spread to mediastinum only
b) Lymphatic spread from subglottis → pretracheal/paratracheal nodes → superior mediastinal nodes → root of neck
c) Spread via occipital nodes then to mediastinum
d) Lymphatic spread from supraglottis only
Answer: b) Lymphatic spread from subglottis → pretracheal/paratracheal nodes → superior mediastinal nodes → root of neck
Explanation: The described sequence reflects the anatomical lymphatic continuity: subglottic drainage to pretracheal/paratracheal nodes, which connect to superior mediastinal nodes and the lower deep cervical nodes at the root of neck. This predictable pathway explains why lower laryngeal cancers can present with lower cervical and mediastinal nodal disease, and it underlines the need for imaging of both neck and superior mediastinum when evaluating subglottic tumors. Hematogenous metastasis is less likely for initial regional nodal disease.
9) During a thyroidectomy with central neck dissection, surgeons must be aware that manipulation of which nodal group is anatomically close to the recurrent laryngeal nerve and parathyroids?
a) Pretracheal and paratracheal nodes (central compartment)
b) Submental nodes
c) Occipital nodes
d) Superficial cervical nodes
Answer: a) Pretracheal and paratracheal nodes (central compartment)
Explanation: The central compartment (level VI) includes pretracheal and paratracheal lymph nodes that sit adjacent to the trachea, recurrent laryngeal nerve, and parathyroid glands. Surgical clearance of these nodes risks injury to the nerve (causing vocal cord palsy) and devascularization of parathyroids (leading to hypocalcemia). In laryngeal and thyroid malignancies involving central nodes, meticulous dissection is required to balance oncologic clearance and preservation of these critical structures.
10) Which imaging modality is most sensitive for detecting small cervical nodal metastases from laryngeal cancer during staging?
a) Contrast-enhanced CT of neck
b) Plain radiograph of neck
c) Abdominal ultrasound
d) PET-CT and/or MRI complement CT for small-volume nodal disease
Answer: d) PET-CT and/or MRI complement CT for small-volume nodal disease
Explanation: Contrast-enhanced CT is commonly used for anatomic staging of head and neck cancers, but PET-CT (FDG PET) and MRI can provide superior sensitivity for small-volume or metabolically active nodal disease; PET-CT is particularly useful for detecting occult metastases and distant spread, while MRI offers excellent soft-tissue contrast for assessment of nodal extracapsular extension. Multimodality imaging is often employed to comprehensively stage laryngeal cancer and to delineate nodal disease for surgical and radiotherapy planning.
Chapter: Head & Neck Anatomy; Topic: Cutaneous Nerve Supply of Face; Subtopic: Sensory Supply to Angle of Mandible
Keyword Definitions:
Greater auricular nerve: Cutaneous branch of cervical plexus (C2–C3) supplying skin over angle of mandible and parotid region.
Cervical plexus: Formed by anterior rami of C1–C4; provides sensory nerves to neck and lower face.
Mandibular nerve: Branch of trigeminal nerve (V3) supplying lower face, but not the angle of mandible.
Maxillary nerve: V2 division of trigeminal nerve supplying midface region.
Angle of mandible: Region just behind the masseter, supplied by cervical nerves, not trigeminal.
1) Lead Question – 2016
Nerve supply to the angle of the mandible is by ?
a) Posterior primary rami of C2, C3
b) Greater auricular nerve
c) Maxillary nerve
d) Mandibular nerve
Answer: b) Greater auricular nerve
Explanation: The angle of the mandible is an important landmark because, although most of the face is supplied by branches of the trigeminal nerve (V1, V2, V3), this specific region is supplied by the greater auricular nerve—a branch of the cervical plexus (C2–C3). This nerve emerges from the posterior border of the sternocleidomastoid and ascends toward the parotid gland, providing sensation to the angle of the mandible, parotid fascia, and lower auricle. Because of this, anesthesia or injury to trigeminal branches cannot block sensation here, and cervical plexus blocks may affect this zone more reliably.
2) The skin over the parotid gland receives its sensory supply from:
a) Auriculotemporal nerve
b) Buccal branch of facial nerve
c) Greater auricular nerve
d) Infraorbital nerve
Answer: c) Greater auricular nerve
Explanation: Although the auriculotemporal nerve provides innervation to the parotid gland itself (secretomotor fibers), the skin over the gland is supplied by the greater auricular nerve, a branch of C2–C3. This nerve travels vertically over the sternocleidomastoid muscle and supplies both the parotid sheath and skin overlying it. Clinically, parotid surgeries require safeguarding this nerve to avoid sensory loss over the region, and pain from parotid inflammation often radiates along its distribution.
3) A patient with cervical plexus block complains of numbness over the angle of mandible. Which nerve was anesthetized?
a) Facial nerve
b) Greater auricular nerve
c) Lingual nerve
d) Buccal nerve
Answer: b) Greater auricular nerve
Explanation: The cervical plexus block targets sensory branches of C2–C4, including the greater auricular nerve. Since the angle of the mandible is supplied by this nerve, numbness in this area indicates successful blockade. This finding differentiates it from facial nerve or trigeminal blocks, which would not anesthetize this region. Clinicians confirm block adequacy by checking sensation around the ear lobe and angle of mandible.
4) Sensation to the lower lip is carried by which nerve?
a) Mental nerve
b) Greater auricular nerve
c) Glossopharyngeal nerve
d) Facial nerve
Answer: a) Mental nerve
Explanation: The mental nerve, a branch of the inferior alveolar nerve (V3), supplies the skin of the chin and lower lip. This differs from the angle of the mandible, which is supplied by cervical nerves. Clinically, mental nerve blocks are useful for dental procedures and chin laceration repair. The mental foramen is the landmark for local anesthesia infiltration.
5) Which nerve supplies sensation to the external acoustic meatus and posterior auricle?
a) Auriculotemporal nerve
b) Greater auricular nerve
c) C3 posterior rami
d) Vestibulocochlear nerve
Answer: a) Auriculotemporal nerve
Explanation: The auriculotemporal nerve (V3) supplies the anterior part of auricle and external acoustic meatus. It carries sensory fibers from the trigeminal nerve, unlike the greater auricular nerve (C2–C3), which supplies the posterior auricle and angle of the mandible. This distribution helps differentiate referred otalgia causes, as dental and TMJ lesions may radiate pain through this nerve.
6) Which muscle lies closest to the emergence point of greater auricular nerve along the posterior border of SCM?
a) Trapezius
b) Digastric
c) Sternocleidomastoid
d) Platysma
Answer: c) Sternocleidomastoid
Explanation: The greater auricular nerve emerges at Erb’s point along the posterior border of the sternocleidomastoid muscle. It then ascends superficially across the SCM toward the parotid region. This predictable course is clinically important during cervical plexus blocks and superficial neck dissections to avoid nerve injury.
7) A patient with trauma to upper cervical roots (C2–C3) will have sensory loss over all except:
a) Angle of mandible
b) Parotid gland skin
c) Lower auricle
d) Upper lip
Answer: d) Upper lip
Explanation: The upper lip is supplied by the infraorbital nerve (V2). C2–C3 injuries affect branches of the cervical plexus, especially the greater auricular nerve, leading to sensory loss over the angle of mandible, parotid region, and lower auricle. Understanding this helps differentiate trigeminal versus cervical nerve lesions.
8) Facial nerve paralysis causes muscle weakness but sensation over the angle of mandible remains intact because it is supplied by:
a) Mandibular nerve
b) Maxillary nerve
c) Greater auricular nerve
d) Buccal branch of facial nerve
Answer: c) Greater auricular nerve
Explanation: The facial nerve is purely motor to facial muscles and does not provide cutaneous sensation (except taste). Thus, even complete facial nerve palsy spares the sensation at the angle of the mandible, as this region is supplied by the greater auricular nerve (C2–C3). This helps clinicians localize nerve injuries.
9) Pain radiating to the angle of the mandible during parotitis follows which nerve pathway?
a) Greater auricular nerve
b) Buccal nerve
c) Inferior alveolar nerve
d) Nasociliary nerve
Answer: a) Greater auricular nerve
Explanation: Parotid swelling stretches the parotid fascia, which is supplied by the greater auricular nerve. This results in referred pain toward the angle of mandible and lower auricle. Knowledge of this pathway aids diagnosis of parotid gland infections and tumors and distinguishes them from trigeminal nerve–related pain.
10) During a superficial parotidectomy, which nerve is most at risk of sensory injury?
a) Auriculotemporal nerve
b) Greater auricular nerve
c) Facial nerve
d) Glossopharyngeal nerve
Answer: b) Greater auricular nerve
Explanation: The greater auricular nerve runs superficially across the sternocleidomastoid and enters the parotid sheath, supplying the overlying skin. During parotidectomy, sacrificing this nerve may lead to numbness over the angle of mandible and lower auricle. Surgeons aim to preserve its posterior branch when possible to reduce postoperative sensory deficits.
11) Which branch of the trigeminal nerve does NOT supply any skin over the mandible?
a) V1
b) V2
c) V3
d) None of the above
Answer: a) V1
Explanation: The ophthalmic division (V1) supplies the forehead, upper eyelid, and nose—not the mandible. Sensory supply to the mandible is mainly via V3 except for the angle of mandible, which is supplied by the greater auricular nerve (C2–C3). This distinction is crucial for facial anesthesia and trauma mapping.
Chapter: Head & Neck Anatomy; Topic: Cutaneous Nerve Supply of Face; Subtopic: Sensory Supply of External Nose
Keyword Definitions:
Ophthalmic division (V1): First division of trigeminal nerve supplying forehead, upper eyelid, dorsum and tip of nose.
Maxillary division (V2): Second division supplying midface including lateral nose and upper lip.
External nasal nerve: Terminal branch of anterior ethmoidal nerve (V1), supplying tip and ala of nose.
Trigeminal nerve: Main sensory nerve of face with three divisions (V1, V2, V3).
Greater auricular nerve: C2–C3 nerve supplying angle of mandible and parotid skin—not nose.
1) Lead Question – 2016
Nerve supply to the tip of the nose is from?
a) The ophthalmic division of the trigeminal nerve
b) Greater auricular nerve
c) The maxillary division of the trigeminal nerve
d) Mandibular nerve
Answer: a) The ophthalmic division of the trigeminal nerve
Explanation: The tip of the nose receives sensory innervation from the external nasal nerve, a branch of the anterior ethmoidal nerve which arises from the ophthalmic division (V1) of the trigeminal nerve. This is a key anatomical distinction because the lateral nose is supplied by V2, but the tip and dorsum are V1 territory. Clinically, this aids in diagnosing sensory deficits after nasal trauma, maxillofacial injuries, or herpetic outbreaks, where lesions limited to the tip of the nose strongly suggest involvement of V1-based nerves.
2) Sensation over the ala of the nose is supplied mainly by:
a) Infraorbital nerve
b) External nasal nerve
c) Greater auricular nerve
d) Mental nerve
Answer: b) External nasal nerve
Explanation: The ala and tip are supplied by the external nasal nerve, a V1 branch. This differentiates it from the lateral nasal wall, which receives infraorbital (V2) innervation. Clinically, trigeminal neuralgia involving V1 may cause pain over the nasal tip region. Understanding the distinction is key in nasal surgeries and local anesthesia blocks.
3) Herpes zoster eruption at the nasal tip (Hutchinson’s sign) indicates involvement of:
a) Maxillary division (V2)
b) Mandibular division (V3)
c) Ophthalmic division (V1)
d) C2–C3 nerves
Answer: c) Ophthalmic division (V1)
Explanation: Hutchinson’s sign refers to vesicles on the nasal tip, indicating involvement of the nasociliary nerve, a branch of V1. This strongly correlates with ocular involvement in herpes zoster ophthalmicus. Recognizing this sign early allows prompt antiviral therapy, preventing corneal complications.
4) Sensory loss over lateral aspect of the nose occurs due to damage of:
a) Infraorbital nerve
b) External nasal nerve
c) Buccal nerve
d) Mental nerve
Answer: a) Infraorbital nerve
Explanation: The lateral nose is supplied by the infraorbital nerve (V2). Trauma to the infraorbital foramen, often seen in maxillary fractures, can impair sensation here. This contrasts with the tip of the nose, which is V1 territory. Precise mapping of sensory territories helps localize nerve injuries.
5) During rhinoplasty, numbness at the nasal tip is expected due to injury of:
a) External nasal nerve
b) Maxillary nerve
c) Mandibular nerve
d) Greater auricular nerve
Answer: a) External nasal nerve
Explanation: The external nasal nerve runs superficially along the nasal dorsum and is frequently stretched during rhinoplasty. Temporary hypoesthesia in this region is common. Knowledge of this branch helps avoid long-term sensory complications.
6) Which nerve enters the nasal cavity through the anterior ethmoidal foramen?
a) Anterior ethmoidal nerve
b) Infraorbital nerve
c) Nasopalatine nerve
d) Buccal nerve
Answer: a) Anterior ethmoidal nerve
Explanation: The anterior ethmoidal nerve (V1 branch) enters the nasal cavity and gives rise to the external nasal nerve, supplying the nasal tip. Its course is important in sinus surgeries because inadvertent damage may cause nasal sensation loss.
7) A patient has decreased sensation over the nasal bridge. Which nerve is likely affected?
a) Supratrochlear nerve
b) Mental nerve
c) Infraorbital nerve
d) Mandibular nerve
Answer: a) Supratrochlear nerve
Explanation: The supratrochlear nerve (V1) supplies the medial upper eyelid and nasal bridge. Blunt trauma or brow surgeries may injure this nerve. Its involvement helps distinguish between V1 and V2 sensory deficits in facial trauma.
8) Sensory supply to nasal septum anteriorly is from:
a) Anterior ethmoidal nerve
b) Greater palatine nerve
c) Mandibular nerve
d) Buccal nerve
Answer: a) Anterior ethmoidal nerve
Explanation: The anterior nasal septum is supplied by the anterior ethmoidal nerve (V1). This is relevant clinically in Little’s area, where epistaxis commonly occurs, and proper anesthesia requires blocking this branch.
9) Which nerve does NOT supply the external nose?
a) V1
b) V2
c) Greater auricular nerve
d) Both V1 and V2
Answer: c) Greater auricular nerve
Explanation: V1 supplies dorsum and tip; V2 supplies lateral nose. The greater auricular nerve (C2–C3) supplies the angle of mandible and parotid skin, not the nose. This distinction helps in trauma mapping and nerve block planning.
10) Which foramen transmits the major nerve supplying the nasal tip?
a) Foramen rotundum
b) Optic canal
c) Anterior ethmoidal foramen
d) Infraorbital foramen
Answer: c) Anterior ethmoidal foramen
Explanation: The anterior ethmoidal nerve exits via the anterior ethmoidal foramen and eventually becomes the external nasal nerve that supplies the nasal tip. Thus, fractures involving the ethmoid region can compromise nasal tip sensation.
11) Pain at the nasal tip radiating to the eye is due to involvement of which nerve?
a) Nasociliary nerve
b) Greater auricular nerve
c) Maxillary nerve
d) Facial nerve
Answer: a) Nasociliary nerve
Explanation: The nasociliary nerve (V1) gives rise to the anterior ethmoidal nerve, which supplies the nasal tip. Disorders such as sinusitis or zoster affecting this nerve produce pain radiating to the eye due to shared sensory pathways. Understanding this helps differentiate ophthalmic versus maxillary nerve involvement.
Chapter: Head & Neck Anatomy; Topic: Deep Cervical Fascia & Spaces; Subtopic: Retropharyngeal & Danger Space
Keyword Definitions:
Buccopharyngeal fascia: Fascial layer covering pharynx and esophagus.
Alar fascia: A subdivision of deep cervical fascia separating retropharyngeal space from danger space.
Prevertebral fascia: Fascia covering vertebral column and associated muscles.
Retropharyngeal space: Space between buccopharyngeal fascia and alar fascia.
Danger space: Space between alar fascia and prevertebral fascia, extends to diaphragm.
1) Lead Question – 2016
Dangerous space in the neck is found between?
a) Buccopharyngeal fascia and alar fascia
b) Prevertebral fascia and alar fascia
c) Buccopharyngeal fascia and Prevertebral fascia
d) None
Answer: b) Prevertebral fascia and alar fascia
Explanation: The dangerous space, also known as “danger space 4,” lies between the alar fascia anteriorly and the prevertebral fascia posteriorly. This space is clinically important because infections originating in the pharynx or retropharyngeal space can spread inferiorly through it directly to the posterior mediastinum up to the diaphragm. Unlike the retropharyngeal space, which ends at T3, the danger space has no inferior limit, making it a conduit for severe mediastinal infection. Therefore, the correct answer is the space between the alar and prevertebral fascia.
2) Retropharyngeal abscess is located between:
a) Buccopharyngeal fascia & alar fascia
b) Alar fascia & prevertebral fascia
c) Carotid sheath layers
d) Investing layer of deep fascia
Answer: a) Buccopharyngeal fascia & alar fascia
Explanation: The retropharyngeal space lies immediately behind the pharynx, bounded anteriorly by buccopharyngeal fascia and posteriorly by alar fascia. Infections here may cause dysphagia or dyspnea. If the infection breaches the alar fascia, it can enter the danger space and descend into the mediastinum.
3) Infection in the danger space may spread inferiorly up to:
a) T3 vertebra
b) Diaphragm
c) Base of skull only
d) Manubrium sterni
Answer: b) Diaphragm
Explanation: The danger space has no inferior boundary and continues from the skull base to the diaphragm. This makes descending necrotizing mediastinitis possible. Clinically, this is life-threatening and requires early surgical drainage.
4) The fascia that forms the posterior boundary of the danger space is:
a) Alar fascia
b) Buccopharyngeal fascia
c) Prevertebral fascia
d) Investing fascia
Answer: c) Prevertebral fascia
Explanation: The prevertebral fascia forms the posterior wall of the danger space. It covers deep muscles of the spine. Infection reaching behind this layer indicates severe deep neck space involvement.
5) Which layer encloses the retropharyngeal lymph nodes?
a) Buccopharyngeal fascia
b) Alar fascia
c) Prevertebral fascia
d) Carotid sheath
Answer: a) Buccopharyngeal fascia
Explanation: Retropharyngeal lymph nodes lie just anterior to the retropharyngeal space, within the buccopharyngeal fascia. These nodes often get infected in children presenting with sore throat, fever, and neck stiffness.
6) A child with dysphagia and neck stiffness likely has abscess in:
a) Retropharyngeal space
b) Danger space
c) Pretracheal space
d) Submandibular space
Answer: a) Retropharyngeal space
Explanation: Retropharyngeal abscess is common in children due to prominent retropharyngeal lymph nodes. Symptoms include drooling, dysphagia, and cervical rigidity. If untreated, infection may rupture into danger space.
7) Carotid sheath contains all except:
a) Internal jugular vein
b) Internal carotid artery
c) Vagus nerve
d) Sympathetic chain
Answer: d) Sympathetic chain
Explanation: The sympathetic chain lies posterior to the carotid sheath, not within it. Knowledge of nearby spaces helps differentiate sources of neck swelling and infection.
8) Infection in prevertebral space may cause:
a) Retropharyngeal bulge
b) Dysphonia
c) Horner syndrome
d) Trismus
Answer: a) Retropharyngeal bulge
Explanation: Prevertebral abscess causes forward displacement of the prevertebral fascia, appearing as a bulge in the posterior pharyngeal wall. It is commonly associated with spinal tuberculosis (Pott's disease).
9) The alar fascia extends from skull base to:
a) T3
b) Diaphragm
c) Mandible
d) Hyoid bone
Answer: a) T3
Explanation: The alar fascia ends around T3 level, forming the posterior border of the retropharyngeal space. Below this, the danger space continues further inferiorly.
10) Which deep neck space lies closest to the pharynx?
a) Retropharyngeal space
b) Danger space
c) Prevertebral space
d) Parapharyngeal space
Answer: d) Parapharyngeal space
Explanation: The parapharyngeal space lies lateral to the pharynx and communicates with other deep neck spaces. Infections here may cause medial displacement of tonsils or airway obstruction.
11) Sudden onset mediastinitis following dental infection suggests spread through:
a) Danger space
b) Retropharyngeal space
c) Carotid sheath
d) Submandibular space
Answer: a) Danger space
Explanation: Dental infections can spread through fascial planes to the pharynx and subsequently enter the danger space, allowing rapid spread into the mediastinum. This life-threatening condition requires urgent intervention.
Chapter: Head & Neck; Topic: Temporomandibular Joint (TMJ); Subtopic: Muscular Attachments of TMJ
Keyword Definitions:
TMJ (Temporomandibular Joint): A synovial joint between mandible & temporal bone.
Articular Disc: Fibrocartilaginous structure dividing TMJ into upper & lower compartments.
Lateral Pterygoid Muscle: Major muscle inserting into TMJ disc & neck of mandible.
Masseter: Elevator of mandible, no attachment to disc.
Temporalis: Inserts into coronoid process, elevates/retracts mandible.
Buccinator: Muscle of cheek, unrelated to TMJ movement.
1) Lead Question – 2016
Which muscle is attached to the disc of the temporomandibular joint?
a) Buccinator
b) Lateral pterygoid
c) Masseter
d) Temporalis
Answer: b) Lateral pterygoid
Explanation: The lateral pterygoid muscle, specifically its superior head, inserts into the articular disc and capsule of the TMJ. This attachment allows the muscle to control anterior movement of the disc during mouth opening. Other muscles like masseter and temporalis act on the mandible but do not attach to the disc. Buccinator plays no role in TMJ mechanics. This unique attachment explains why disc displacement is commonly associated with lateral pterygoid hyperactivity.
2) Which muscle primarily assists in protrusion of the mandible?
a) Medial pterygoid
b) Lateral pterygoid
c) Masseter
d) Temporalis
Answer: b) Lateral pterygoid
Explanation: The lateral pterygoid is the only muscle that pulls the mandibular condyle and disc forward, producing protrusion. Medial pterygoid assists slightly but is mainly an elevator. Temporalis retracts, and masseter mainly elevates the mandible.
3) A patient with TMJ clicking likely has dysfunction involving:
a) Masseter
b) Lateral pterygoid
c) Mylohyoid
d) Stylohyoid
Answer: b) Lateral pterygoid
Explanation: Clicking occurs when the articular disc displaces anteriorly due to imbalance or hyperactivity of the lateral pterygoid, which is attached to the disc.
4) Depression (opening) of the mouth is initiated mainly by:
a) Gravity
b) Lateral pterygoid
c) Masseter
d) Buccinator
Answer: a) Gravity
Explanation: Initial mouth opening is passive due to gravity; full opening requires contraction of lateral pterygoid.
5) Which muscle assists in retraction of the mandible?
a) Posterior fibers of temporalis
b) Buccinator
c) Medial pterygoid
d) Lateral pterygoid
Answer: a) Posterior fibers of temporalis
Explanation: Posterior temporalis fibers pull the mandible backward; pterygoids protrude instead.
6) TMJ disc is primarily composed of:
a) Hyaline cartilage
b) Fibrocartilage
c) Elastic cartilage
d) Keratinized cartilage
Answer: b) Fibrocartilage
Explanation: Unlike most synovial joints, TMJ has a fibrocartilaginous disc, allowing durability during mastication.
7) Injury to which nerve affects TMJ movements?
a) Auriculotemporal nerve
b) Facial nerve
c) Hypoglossal nerve
d) Spinal accessory nerve
Answer: a) Auriculotemporal nerve
Explanation: Auriculotemporal nerve (branch of V3) supplies sensory innervation to TMJ; V3 supplies muscles of mastication including lateral pterygoid.
8) Which artery supplies TMJ?
a) Maxillary artery
b) Facial artery
c) Lingual artery
d) Superior thyroid artery
Answer: a) Maxillary artery
Explanation: TMJ receives blood mainly from maxillary artery branches, including deep auricular artery.
9) During wide mouth opening, the condyle moves:
a) Upward
b) Downward and forward
c) Backward
d) None
Answer: b) Downward and forward
Explanation: The lateral pterygoid pulls the condyle and disc forward onto the articular eminence.
10) Teeth clenching involves strongest contraction of:
a) Masseter
b) Buccinator
c) Styloglossus
d) Superior constrictor
Answer: a) Masseter
Explanation: Masseter is the strongest muscle of mastication, responsible for forceful elevation of the jaw.
11) Pain in the preauricular region during chewing suggests pathology of:
a) TMJ
b) Stylomastoid foramen
c) Hypoglossal canal
d) Nasal cavity
Answer: a) TMJ
Explanation: TMJ dysfunction presents with preauricular pain, clicking, limited jaw movement, or deviation to one side.
Chapter: Head & Neck Anatomy; Topic: Muscles of Mastication; Subtopic: Attachments around Maxilla
Keyword Definitions:
Maxillary Tuberosity: Rounded posterior part of maxilla giving attachment to medial pterygoid.
Medial Pterygoid: Muscle assisting mastication; attaches to tuberosity & lateral pterygoid plate.
Lateral Pterygoid: Protrudes mandible; no attachment to maxillary tuberosity.
Masseter: Inserts on ramus of mandible; no attachment to tuberosity.
Temporalis: Inserts on coronoid process; unrelated to tuberosity.
1) Lead Question – 2016
Maxillary tubercle gives attachment to?
a) Lateral pterygoid
b) Medial pterygoid
c) Temporalis
d) Masseter
Answer: b) Medial pterygoid
Explanation: The medial pterygoid muscle arises from the medial surface of the lateral pterygoid plate and the maxillary tuberosity. This posterior maxillary prominence provides a strong anchor point for this elevator of the mandible. None of the other muscles—masseter, temporalis, or lateral pterygoid—attach to the maxillary tuberosity. Understanding this attachment is clinically relevant in maxillary fractures and posterior maxillary nerve blocks.
2) Fibers of medial pterygoid run in the same direction as:
a) Lateral pterygoid
b) Masseter
c) Buccinator
d) Temporalis
Answer: b) Masseter
Explanation: The medial pterygoid and masseter form a muscular sling elevating the mandible, with nearly parallel fiber orientation.
3) Medial pterygoid is supplied by:
a) Facial nerve
b) Mandibular nerve (V3)
c) Glossopharyngeal nerve
d) Hypoglossal nerve
Answer: b) Mandibular nerve (V3)
Explanation: All muscles of mastication, including the medial pterygoid, receive motor supply from V3.
4) Action of medial pterygoid includes:
a) Depression of mandible
b) Elevation and side-to-side movement
c) Retraction
d) Protraction only
Answer: b) Elevation and side-to-side movement
Explanation: Along with masseter, it elevates the mandible and produces grinding movements.
5) A blowout fracture of posterior maxilla may affect the attachment of:
a) Buccinator
b) Medial pterygoid
c) Temporalis
d) Orbicularis oris
Answer: b) Medial pterygoid
Explanation: The medial pterygoid attaches to the maxillary tuberosity; fractures here affect its function.
6) Which muscle helps in protrusion of mandible?
a) Temporalis
b) Masseter
c) Lateral pterygoid
d) Mylohyoid
Answer: c) Lateral pterygoid
Explanation: The only major muscle that protrudes the mandible is the lateral pterygoid.
7) Which structure lies medial to medial pterygoid?
a) Parotid gland
b) Tensor veli palatini
c) Pharyngeal wall
d) Mandibular ramus
Answer: c) Pharyngeal wall
Explanation: The medial pterygoid forms the lateral boundary of the pharyngeal wall.
8) Medial pterygoid forms part of:
a) Infratemporal fossa
b) Parapharyngeal space
c) Pterygopalatine fossa
d) Nasal cavity
Answer: a) Infratemporal fossa
Explanation: It occupies the infratemporal fossa and contributes to mastication mechanics.
9) Paralysis of medial pterygoid results in:
a) Inability to protrude mandible
b) Deviation of jaw to opposite side
c) Weak elevation of mandible
d) Excessive retraction
Answer: c) Weak elevation of mandible
Explanation: Medial pterygoid is a major elevator; paralysis weakens closure of mouth.
10) Which artery supplies medial pterygoid?
a) Facial artery
b) Inferior alveolar artery
c) Maxillary artery
d) Lingual artery
Answer: c) Maxillary artery
Explanation: Branches of the maxillary artery supply muscles of mastication.
11) Medial pterygoid is separated from ramus of mandible by:
a) Pterygomandibular raphe
b) Parotid duct
c) Mylohyoid line
d) Buccal fat pad
Answer: a) Pterygomandibular raphe
Explanation: The raphe forms an important landmark between buccinator and superior constrictor, lying close to the medial pterygoid.
Chapter: Head & Neck Anatomy; Topic: Pterygopalatine Fossa & Nerve Pathways; Subtopic: Vidian Nerve (Nerve of Pterygoid Canal)
Keyword Definitions:
Vidian Nerve: Formed by union of greater petrosal (parasympathetic) and deep petrosal (sympathetic) nerves.
Nerve of Pterygoid Canal: Another name for Vidian nerve; passes through pterygoid canal.
Greater Petrosal Nerve: Parasympathetic branch from facial nerve; NOT same as Vidian nerve.
Deep Petrosal Nerve: Sympathetic fibers contributing to Vidian nerve.
Pterygopalatine Ganglion: Parasympathetic relay ganglion receiving Vidian nerve.
1) Lead Question – 2016
Vidian nerve is also known as?
a) Nerve of Pterygoid canal
b) Greater Petrosal nerve
c) Lesser Petrosal nerve
d) Greater Auricular nerve
Answer: a) Nerve of Pterygoid canal
Explanation: The Vidian nerve is classically known as the “nerve of the pterygoid canal.” It is formed by the union of the greater petrosal nerve (parasympathetic fibers) and the deep petrosal nerve (sympathetic fibers). It passes through the pterygoid canal into the pterygopalatine fossa and carries autonomic fibers to the pterygopalatine ganglion. Greater or lesser petrosal nerves are components but not synonyms. The greater auricular nerve is unrelated.
2) Vidian nerve carries which type of fibers?
a) Pure parasympathetic
b) Pure sympathetic
c) Mixed autonomic fibers
d) Pure sensory
Answer: c) Mixed autonomic fibers
Explanation: It includes both parasympathetic (greater petrosal) and sympathetic (deep petrosal) fibers forming a mixed nerve.
3) The greater petrosal nerve is a branch of?
a) Glossopharyngeal nerve
b) Facial nerve
c) Trigeminal nerve
d) Vagus nerve
Answer: b) Facial nerve
Explanation: The greater petrosal arises from the geniculate ganglion of facial nerve.
4) Vidian nerve enters which fossa?
a) Infratemporal fossa
b) Pterygopalatine fossa
c) Parotid fossa
d) Retropharyngeal space
Answer: b) Pterygopalatine fossa
Explanation: It ends in the pterygopalatine fossa to reach its ganglion.
5) Deep petrosal nerve fibers originate from:
a) Otic ganglion
b) Stellate ganglion
c) Internal carotid plexus
d) Ciliary ganglion
Answer: c) Internal carotid plexus
Explanation: Sympathetic deep petrosal fibers arise from carotid plexus and merge to form Vidian nerve.
6) Parasympathetic fibers of Vidian nerve synapse in:
a) Otic ganglion
b) Pterygopalatine ganglion
c) Submandibular ganglion
d) Ciliary ganglion
Answer: b) Pterygopalatine ganglion
Explanation: The Vidian nerve brings preganglionic parasympathetics to the pterygopalatine ganglion.
7) A lesion of Vidian nerve causes decreased secretion in:
a) Parotid gland
b) Lacrimal gland
c) Submandibular gland
d) Thyroid gland
Answer: b) Lacrimal gland
Explanation: Parasympathetic fibers via Vidian → pterygopalatine ganglion → lacrimal gland.
8) Vidian canal lies in which bone?
a) Maxilla
b) Zygomatic
c) Sphenoid
d) Mandible
Answer: c) Sphenoid
Explanation: The pterygoid canal (Vidian canal) runs through the sphenoid bone.
9) Vidian nerve damage may result in dryness of:
a) Nasal mucosa
b) Pharynx
c) Tongue
d) External ear
Answer: a) Nasal mucosa
Explanation: Loss of parasympathetic supply through the pterygopalatine ganglion reduces nasal gland secretion.
10) Greater petrosal nerve joins deep petrosal at:
a) Foramen rotundum
b) Foramen spinosum
c) Lacerum region
d) Jugular foramen
Answer: c) Lacerum region
Explanation: The union occurs near the foramen lacerum before entering the pterygoid canal.
11) Vidian nerve does NOT supply:
a) Nasal glands
b) Palatine glands
c) Lacrimal gland (via zygomatic nerve)
d) Parotid gland
Answer: d) Parotid gland
Explanation: Parotid is supplied via glossopharyngeal → lesser petrosal → otic ganglion, unrelated to Vidian nerve.
Chapter: Neuroanatomy; Topic: Brainstem Functional Columns; Subtopic: General Visceral Afferent (GVA) Nuclei
Keyword Definitions:
General Visceral Afferent (GVA): Sensory fibers that carry visceral sensations from thoracic, abdominal, and pelvic organs.
Dorsal Nucleus of Vagus: Major GVA nucleus receiving input from thoracic and abdominal viscera.
Nucleus Ambiguus: Motor nucleus (SVE), NOT GVA.
Trigeminal Nucleus: Receives somatic sensation (GSA), not visceral.
Facial Nerve Nucleus: Motor/Special sensory, not GVA.
1) Lead Question – 2016
Which of the following nuclei belong to the general visceral afferent column?
a) Facial nerve nucleus
b) Trigeminal nucleus
c) Dorsal nucleus of vagus
d) Nucleus ambiguus
Answer: c) Dorsal nucleus of vagus
Explanation: The dorsal nucleus of the vagus is the primary GVA nucleus in the brainstem. It receives visceral afferents from thoracic and abdominal organs, including heart, lungs, and gut. The facial nerve nucleus and nucleus ambiguus are motor nuclei, while the trigeminal nucleus receives somatic, not visceral, sensation. Thus, only the dorsal nucleus of vagus belongs to the GVA column.
2) GVA fibers from carotid sinus synapse in:
a) Nucleus solitarius
b) Chief sensory nucleus of V
c) Nucleus ambiguus
d) Motor nucleus of VII
Answer: a) Nucleus solitarius
Explanation: The nucleus solitarius receives taste and visceral afferent inputs from cranial nerves IX and X, including the carotid sinus baroreceptors.
3) Visceral afferent fibers from abdominal organs reach CNS mainly via:
a) Glossopharyngeal
b) Facial nerve
c) Vagus nerve
d) Hypoglossal
Answer: c) Vagus nerve
Explanation: The vagus nerve carries the majority of visceral sensations from thoracic and abdominal organs to the dorsal vagal nucleus and nucleus solitarius.
4) Lesion of dorsal vagal nucleus may cause:
a) Loss of gag reflex
b) Altered visceral reflexes
c) Facial paralysis
d) Hypoglossal palsy
Answer: b) Altered visceral reflexes
Explanation: Because this nucleus regulates visceral sensations and reflexes, its injury disrupts autonomic responses.
5) Taste fibers (special visceral afferent) from anterior tongue terminate in:
a) Nucleus solitarius
b) Dorsal vagal nucleus
c) Trigeminal motor nucleus
d) Facial motor nucleus
Answer: a) Nucleus solitarius
Explanation: The rostral part of the nucleus solitarius (gustatory nucleus) receives taste sensations.
6) Pain from heart is carried mainly by:
a) Somatic afferents
b) Sympathetic visceral afferents
c) Parasympathetic visceral afferents only
d) Spinal accessory nerve
Answer: b) Sympathetic visceral afferents
Explanation: Cardiac pain is transmitted through sympathetic GVA fibers to upper thoracic spinal segments.
7) Parasympathetic visceral inputs to nucleus solitarius come via:
a) III, IV
b) VII, IX, X
c) V, VIII
d) XI, XII
Answer: b) VII, IX, X
Explanation: These cranial nerves carry visceral and taste sensations to the nucleus solitarius.
8) A patient with bilateral dorsovagal nucleus lesion may show:
a) Loss of voluntary limb movement
b) Severe autonomic dysfunction
c) Complete facial anesthesia
d) Loss of smell
Answer: b) Severe autonomic dysfunction
Explanation: The dorsal nucleus is key to regulating autonomic visceral function; damage affects heart rate and gut motility.
9) Which nucleus is NOT part of visceral afferent pathways?
a) Nucleus solitarius
b) Dorsal nucleus of vagus
c) Nucleus ambiguus
d) Carotid sinus nerve nucleus
Answer: c) Nucleus ambiguus
Explanation: The nucleus ambiguus is a motor nucleus (SVE) supplying pharyngeal muscles.
10) Which nerve carries both taste and visceral afferents?
a) Hypoglossal
b) Vagus
c) Spinal accessory
d) Trochlear
Answer: b) Vagus
Explanation: Vagus carries taste (epiglottis) and GVA fibers from thoracoabdominal organs.
11) Visceral reflexes like vomiting are integrated in:
a) Facial motor nucleus
b) Solitary nucleus
c) Abducens nucleus
d) Spinal trigeminal nucleus
Answer: b) Solitary nucleus
Explanation: The solitary nucleus integrates visceral sensory input essential for autonomic reflexes.
Chapter: Neck Anatomy; Topic: Nerves of the Larynx; Subtopic: Recurrent Laryngeal Nerve Course
Keyword Definitions:
Recurrent Laryngeal Nerve (RLN): Branch of vagus nerve that loops and ascends to supply intrinsic laryngeal muscles.
Right RLN: Loops around right subclavian artery; shorter and more oblique path.
Left RLN: Loops around aortic arch; longer intrathoracic course.
Vagus Nerve: CN X giving motor and sensory supply to pharynx, larynx, and thoracic structures.
Inferior Laryngeal Nerve: Terminal part of RLN entering larynx.
1) Lead Question – 2016
Right Recurrent laryngeal nerve loops around?
a) Right subclavian artery
b) Right axillary artery
c) Right External carotid artery
d) Right Superior thyroid artery
Answer: a) Right subclavian artery
Explanation: The right recurrent laryngeal nerve branches from the vagus in the root of the neck and loops around the right subclavian artery before ascending in the tracheoesophageal groove. This looping pattern differs from the left RLN, which loops under the aortic arch. After looping, the nerve travels superiorly to supply all intrinsic laryngeal muscles except cricothyroid. Damage may occur during thyroid or parathyroid surgery.
2) The left recurrent laryngeal nerve loops under:
a) Aortic arch
b) Pulmonary artery
c) Subclavian vein
d) Brachiocephalic vein
Answer: a) Aortic arch
Explanation: The left RLN loops beneath the aortic arch near the ligamentum arteriosum before ascending toward the larynx.
3) Injury to recurrent laryngeal nerve causes:
a) Loss of pitch control
b) Hoarseness
c) Inability to swallow solids
d) Loss of gag reflex
Answer: b) Hoarseness
Explanation: RLN injury affects intrinsic laryngeal muscles, leading to vocal cord paralysis and hoarseness.
4) A patient with mediastinal tumor compressing the left RLN will present with:
a) Nasal regurgitation
b) Hoarse voice
c) Tongue deviation
d) Facial paralysis
Answer: b) Hoarse voice
Explanation: The longer intrathoracic course of the left RLN makes it vulnerable to mediastinal masses.
5) RLN supplies all intrinsic laryngeal muscles except:
a) Cricothyroid
b) Posterior cricoarytenoid
c) Lateral cricoarytenoid
d) Thyroarytenoid
Answer: a) Cricothyroid
Explanation: Cricothyroid is supplied by external laryngeal nerve (branch of superior laryngeal nerve).
6) The RLN ascends in which anatomical groove?
a) Carotid sheath
b) Tracheoesophageal groove
c) Retropharyngeal space
d) Submandibular space
Answer: b) Tracheoesophageal groove
Explanation: This groove provides a protected pathway for RLN ascent toward the larynx.
7) Most common cause of bilateral RLN palsy:
a) Stroke
b) Thyroid surgery
c) Mastoidectomy
d) Lung cancer
Answer: b) Thyroid surgery
Explanation: Close proximity to the inferior thyroid artery makes the RLN vulnerable during thyroidectomy.
8) Recurrent laryngeal nerve provides sensory supply to:
a) Supraglottis
b) Glottis
c) Infraglottis
d) Epiglottis
Answer: c) Infraglottis
Explanation: Sensory innervation below vocal cords is via the inferior laryngeal nerve (terminal RLN branch).
9) A patient with voice fatigue and aspiration likely has injury to:
a) Glossopharyngeal
b) External laryngeal
c) Recurrent laryngeal nerve
d) Hypoglossal
Answer: c) Recurrent laryngeal nerve
Explanation: RLN injury impairs glottic closure, leading to aspiration and weak voice.
10) RLN injury during PDA ligation affects mostly:
a) Right RLN
b) Left RLN
c) Both equally
d) None
Answer: b) Left RLN
Explanation: The left RLN loops near ligamentum arteriosum and is at risk during PDA repair.
11) The nerve entering larynx below the inferior constrictor is:
a) Internal laryngeal nerve
b) External laryngeal nerve
c) Inferior laryngeal nerve
d) Glossopharyngeal nerve
Answer: c) Inferior laryngeal nerve
Explanation: This is the continuation of RLN after its ascent, supplying motor and sensory functions.
Chapter: Neck & Thorax Anatomy; Topic: Recurrent Laryngeal Nerve; Subtopic: Course of Left Recurrent Laryngeal Nerve
Keyword Definitions:
Recurrent Laryngeal Nerve (RLN): Branch of vagus nerve supplying intrinsic laryngeal muscles except cricothyroid.
Left RLN: Loops under the arch of aorta and ascends in the tracheoesophageal groove.
Tracheoesophageal Groove: Anatomical space between trachea and esophagus where RLN runs.
Vagus Nerve: Cranial nerve X giving rise to superior and recurrent laryngeal branches.
Inferior Laryngeal Nerve: Terminal continuation of recurrent laryngeal nerve.
1) Lead Question – 2016
Left recurrent laryngeal passes between?
a) Trachea & larynx
b) Trachea & esophagus
c) Esophagus and bronchi
d) Esophagus and aorta
Answer: b) Trachea & esophagus
Explanation: The left recurrent laryngeal nerve hooks under the arch of aorta near the ligamentum arteriosum and then ascends in the tracheoesophageal groove, which lies between the trachea and esophagus. This pathway makes it vulnerable in surgeries such as esophagectomy, thyroidectomy, and mediastinal procedures. The nerve supplies all intrinsic laryngeal muscles except cricothyroid and provides sensory innervation to the infraglottic region. Its long intrathoracic course explains why left RLN palsy occurs more commonly in mediastinal tumors.
2) Which nerve supplies intrinsic laryngeal muscles except cricothyroid?
a) Superior laryngeal nerve
b) Recurrent laryngeal nerve
c) Glossopharyngeal nerve
d) Hypoglossal nerve
Answer: b) Recurrent laryngeal nerve
Explanation: RLN provides motor supply to all intrinsic laryngeal muscles except cricothyroid, which is supplied by external laryngeal nerve.
3) The left recurrent laryngeal nerve hooks around:
a) Right subclavian artery
b) Aortic arch
c) Brachiocephalic trunk
d) Pulmonary artery
Answer: b) Aortic arch
Explanation: It loops under the aortic arch near the ligamentum arteriosum before ascending.
4) Compression of the left RLN may occur in:
a) Thyroid cyst
b) Left atrial enlargement
c) Submandibular mass
d) Parotid swelling
Answer: b) Left atrial enlargement
Explanation: Left atrial enlargement (Ortner’s syndrome) compresses the left RLN causing hoarseness.
5) Sensory supply below vocal cords is via:
a) Internal laryngeal nerve
b) Inferior laryngeal nerve
c) Glossopharyngeal nerve
d) Facial nerve
Answer: b) Inferior laryngeal nerve
Explanation: Inferior laryngeal nerve is the terminal part of RLN and supplies infraglottic mucosa.
6) A patient with hoarseness and mediastinal mass most likely has involvement of:
a) Right RLN
b) Left RLN
c) Hypoglossal nerve
d) Spinal accessory nerve
Answer: b) Left RLN
Explanation: The longer thoracic course makes left RLN more prone to mediastinal compression.
7) Right RLN loops around:
a) Right subclavian artery
b) Right common carotid artery
c) Aortic arch
d) Brachiocephalic vein
Answer: a) Right subclavian artery
Explanation: The right vagus gives off RLN which loops around the right subclavian artery.
8) RLN injury during thyroid surgery is due to its relation with:
a) Superior thyroid artery
b) Inferior thyroid artery
c) Middle thyroid vein
d) Cricothyroid membrane
Answer: b) Inferior thyroid artery
Explanation: RLN crosses close to inferior thyroid artery branches, risking damage.
9) RLN supplies all except:
a) Posterior cricoarytenoid
b) Lateral cricoarytenoid
c) Cricothyroid
d) Thyroarytenoid
Answer: c) Cricothyroid
Explanation: Cricothyroid is supplied by the external laryngeal nerve.
10) Unilateral RLN palsy leads to:
a) Aphonia
b) Hoarseness
c) Breathy voice loss
d) Complete airway obstruction
Answer: b) Hoarseness
Explanation: Paralysis of one vocal cord results in hoarseness but airway remains adequate.
11) RLN ascends toward the larynx in:
a) Retropharyngeal space
b) Tracheoesophageal groove
c) Parapharyngeal space
d) Carotid sheath
Answer: b) Tracheoesophageal groove
Explanation: This anatomical pathway protects but also clinically exposes RLN during esophageal or thyroid surgery.