Head and Neck V Flashcards
Which of the following structures is not transmitted by the jugular foramen?
A. Hypoglossal nerve B. Accessory nerve C. Internal jugular vein D. Inferior petrosal sinus E. Vagus nerve
Contents of the jugular foramen:
Anterior: inferior petrosal sinus
Intermediate: glossopharyngeal, vagus, and accessory nerves
Posterior: sigmoid sinus (becoming the internal jugular vein) and some meningeal branches from the occipital and ascending pharyngeal arteries
Theme from 2009 exam
The jugular foramen may be divided into three compartments:
Anterior compartment transmits the inferior petrosal sinus
Middle compartment transmits cranial nerves IX, X and XI
Posterior compartment transmits the sigmoid sinus
A 19 year old female is admitted with suspected meningitis. The House Officer is due to perform a lumbar puncture. What is the most likely structure first encountered when the needle is inserted?
A. Ligamentum flavum B. Denticulate ligament C. Dural sheath D. Pia Mater E. Supraspinous ligament
Supraspinous ligament
Lumbar punctures are performed to obtain cerebrospinal fluid. In adults, the procedure is best performed at the level of L3/L4 or L4/5 interspace. These regions are below the termination of the spinal cord at L1.
During the procedure the needle passes through:
The supraspinous ligament which connects the tips of spinous processes and the interspinous ligaments between adjacent borders of spinous processes
Then the needle passes through the ligamentum flavum, which may cause a give as it is penetrated
A second give represents penetration of the needle through the dura mater into the subarachnoid space. Clear CSF should be obtained at this point
What is the correct embryological origin of the stapes?
A. First pharyngeal arch B. Second pharyngeal arch C. Third pharyngeal arch D. Fourth pharyngeal arch E. Fifth pharyngeal arch
2nd branch
The dorsal ends of the cartilages of the first and second pharyngeal arches articulate superior to the tubotympanic recess. These cartilages form the malleus, incus and stapes. At least part of the malleus is formed from the first arch and the stapes from the second arch. The incus is most likely to arise from the first arch.
A 73 year old man presents with a tumour at the central aspect of the posterior third of the tongue. To which of the following lymph node groups is it most likely to metastasise?
A. Submental B. Submandibular C. Ipsilateral deep cervical nodes D. Contralateral deep cervical nodes E. Bilateral deep cervical nodes
Bilateral deep cervical nodes
Posterior third tumours of the tongue commonly metastasise to the bilateral deep cervical lymph nodes
Tumours of the posterior third of the tongue will typically metastasise early and bilateral nodal involvement is well recognised, this is most often true of centrally located tumours and those adjacent to the midline as the lymph vessels may cross the median plane at this location.
A 34 year old lady suffers from hyperparathyroidism. The right inferior parathyroid is identified as having an adenoma and is scheduled for resection. From which of the following embryological structures is it derived?
A. Second pharyngeal pouch B. Third pharyngeal pouch C. Fourth pharyngeal pouch D. First pharyngeal pouch E. None of the above
3rd
The inferior parathyroid is a derivative of the third pharyngeal pouch. The superior parathyroid originates from the fourth pharyngeal pouch.
A 56 year old man is undergoing a superficial parotidectomy for a pleomorphic adenoma. During the dissection of the parotid, which of the following structures will be encountered lying most superficially?
A. Facial nerve B. External carotid artery C. Occipital artery D. Maxillary artery E. Retromandibular vein
Facial
Most superficial structure on the parotid gland = facial nerve
The facial nerve is the most superficial structure in the parotid gland. Slightly deeper to this lies the retromandibular vein, with the arterial layer lying most deeply.
A 78 year old man is due to undergo an endarterectomy of the internal carotid artery. Which of the following nervous structures are most at risk during the dissection?
A. Recurrent laryngeal nerve B. Sympathetic chain C. Hypoglossal nerve D. Phrenic nerve E. Lingual nerve
Hypoglossal
Nerves at risk during a carotid endarterectomy:
Hypoglossal nerve
Greater auricular nerve
Superior laryngeal nerve
During a carotid endarterectomy the sternocleidomastoid muscle is dissected, with ligation of the common facial vein and then the internal jugular is dissected exposing the common and the internal carotid arteries. The nerves at risk during the operation include:
Hypoglossal nerve
Greater auricular nerve
Superior laryngeal nerve
The sympathetic chain lies posteriorly and is less prone to injury in this procedure.
Which of the following fascial structures encases the apex of the lungs?
A. Waldeyers fascia B. Sibsons fascia C. Pretracheal fascia D. Clavipectoral fascia E. None of the above
Sibson’s fascia overlies the apices of both lungs
The suprapleural fascia (Sibson’s fascia) runs from C7 to the first rib and overlies the apex of both lungs.It lies between the parietal pleura and the thoracic cage.
With regards to the jugular vein, which of the following statements is untrue?
A. It lies within the carotid sheath B. It is the continuation of the sigmoid sinus C. The terminal part of the thoracic duct crosses anterior to it to insert into the right subclavian vein D. The hypoglossal nerve is closely related to it as it passes near the atlas E. The vagus nerve is closely related to it within the carotid sheath
C
Each jugular vein begins in the jugular foramen, where they are the continuation of the sigmoid sinus. They terminate at the medial end of the clavicle where they unite with the subclavian vein.
The vein lies within the carotid sheath throughout its course. Below the skull the internal carotid artery and last four cranial nerves are anteriomedial to the vein. Thereafter it is in contact medially with the internal (then common) carotid artery. The vagus lies posteromedially.
At its superior aspect the vein is overlapped by sternocleidomastoid and covered by it at the inferior aspect of the vein.
Below the transverse process of the atlas it is crossed on its lateral side by the accessory nerve. At its mid point it is crossed by the inferior root of the ansa cervicalis.
Posterior to the vein are the transverse processes of the cervical vertebrae, the phenic nerve as it descends on the scalenus anterior, and the first part of the subclavian artery. On the left side its also related to the thoracic duct.
A 43 year old man is stabbed outside a nightclub. He suffers a transection of his median nerve just as it leaves the brachial plexus. Which of the following features is least likely to ensue?
A. Ulnar deviation of the wrist B. Complete loss of wrist flexion C. Loss of pronation D. Loss of flexion at the thumb joint E. Inability to oppose the thumb
Complete loss of wrist flexion
Loss of the median nerve will result in loss of function of the flexor muscles. However, flexor carpi ulnaris will still function and produce ulnar deviation and some residual wrist flexion. High median nerve lesions result in complete loss of flexion at the thumb joint.
Which of the following anatomical structures lies within the spiral groove of the humerus?
A. Median nerve B. Radial nerve C. Tendon of triceps D. Musculocutaneous nerve E. Axillary nerve
The radial nerve lies in this groove and may be compromised by fractures involving the shaft.
A 24 year old man falls and sustains a fracture through his scaphoid bone. From which of the following areas does the scaphoid derive the majority of its blood supply?
A. From its proximal medial border B. From its proximal lateral border C. From its proximal posterior surface D. From the proximal end E. From the distal end
The blood supply to the scaphoid enters from a small non articular surface near its distal end. Transverse fractures through the scaphoid therefore carry a risk of non union.
Which of the following cranial venous sinuses is unpaired?
A. Transverse sinus B. Superior sagittal sinus C. Cavernous sinus D. Sigmoid sinus E. Inferior petrosal sinus
The superior sagittal sinus is unpaired
The superior sagittal sinus is unpaired. It begins at the crista galli, where it may communicate with the veins of the frontal sinus and sometimes with those of the nasal cavity. It arches backwards in the falx cerebri to terminate at the internal occipital protuberance (usually into the right transverse sinus). The parietal emissary veins link the superior sagittal sinus with the veins on the exterior of the cranium.
Which of the following laryngeal tumours will not typically metastasise to the cervical lymph nodes?
A. Glottic B. Supraglottic C. Subglottic D. Transglottic E. Aryepiglottic fold
Glottic
The vocal cords have no lymphatic drainage and therefore this region serves as a lymphatic watershed. The supraglottic part drains to the upper deep cervical nodes through vessels piercing the thyrohyoid membrane. The sub glottic part drains to the pre laryngeal, pre tracheal and inferior deep cervical nodes. The aryepiglottic and vestibular folds have a rich lymphatic drainage and will metastasise early.
Which of the following forms the medial wall of the femoral canal?
A. Pectineal ligament B. Adductor longus C. Sartorius D. Lacunar ligament E. Inguinal ligament
Lacunar
The femoral canal lies at the medial aspect of the femoral sheath. The femoral sheath is a fascial tunnel containing both the femoral artery laterally and femoral vein medially. The canal lies medial to the vein.
Borders of the femoral canal Laterally Femoral vein Medially Lacunar ligament Anteriorly Inguinal ligament Posteriorly Pectineal ligament
An 18 year old man is cutting some plants when a small piece of vegetable matter enters his eye. His eye becomes watery. Which of the following is responsible for relaying parasympathetic neuronal signals to the lacrimal apparatus?
A. Pterygopalatine ganglion B. Otic ganglion C. Submandibular ganglion D. Ciliary ganglion E. None of the above
Pterygopalatine ganglion
The parasympathetic fibres to the lacrimal apparatus transit via the pterygopalatine ganglion.
A 43 year old lady is undergoing a total thyroidectomy for an extremely large goitre. The surgeons decide that access may be improved by division of the infra hyoid strap muscles. At which of the following sites should they be divided?
A. In their upper half B. In their lower half C. In the middle D. At their origin from the hyoid E. At the point of their insertion
In their upper half
Should the strap muscles require division during surgery they should be divided in their upper half. This is because their nerve supply from the ansa cervicalis enters in their lower half.
A 22 year old women has recently undergone a surgical excision of the submandibular gland. She presents to the follow up clinic with a complaint of tongue weakness on the ipsilateral side to her surgery. Which nerve has been damaged?
A. Hypoglossal nerve B. Lingual nerve C. Inferior alveolar nerve D. Facial nerve E. Lesser petrosal nerve
Hypoglossal nerve
Three cranial nerves may be injured during submandibular gland excision.
Marginal mandibular branch of the facial nerve
Lingual nerve
Hypoglossal nerve
Theme from April 2012 Exam
Hypoglossal nerve damage may result in paralysis of the ipsilateral aspect of the tongue. The nerve itself lies deep to the capsule surrounding the gland and should not be injured during an intracapsular dissection. The lingual nerve is probably at greater risk of injury. However, the effects of lingual nerve injury are sensory rather than motor.
A 67 year old man undergoes a carotid endarterectomy and seems to recover well following surgery. When he is reviewed on the ward post operatively he complains that his voice is hoarse. What is the most likely cause?
A. Damage to the accessory nerve B. Damage to the cervical plexus C. Damage to the glossopharyngeal nerve D. Damage to the hypoglossal nerve E. Damage to the vagus
Many of these nerves are at risk of injury during carotid surgery. However, only damage to the vagus would account for difficulties in speech.
A 12 year old boy undergoes surgery for recurrent mastoid infections. Post operatively he complains of an altered taste sensation. Which of the following nerves has been injured?
A. Glossopharyngeal B. Greater petrosal C. Olfactory D. Trigeminal E. Chorda tympani
Submit answer
Chorda tympani
The chorda tympani branch of the facial nerve passes forwards through itrs canaliculus into the middle ear, and crosses the medial aspect of the tympanic membrane. It then passes antero-inferiorly in the infratemporal fossa. It distributes taste fibres to the anterior two thirds of the tongue.
Which of the structures listed below is not a content of the carotid sheath?
A. Internal jugular vein B. Internal carotid artery C. Vagus nerve D. Recurrent laryngeal nerve E. Common carotid artery
Contents of carotid sheath: Common carotid artery Internal carotid artery Internal jugular vein Vagus nerve
A 22 year old man is undergoing a wedge excision of his great toenail. As the surgeon passes a needle into the area to administer local anaesthetic, the patient notices a sharp pain. By which pathway will this sensation be conveyed to the central nervous system?
A. Anterior corticospinal tract B. Posterior spinocerebellar tract C. Cuneate fasciculus D. Vestibulospinal tract E. Spinothalamic tract
Spinothalamic tract- Pain and temperature
Vestibulospinal tract- Motor neuronal signals relating to posture
Cuneate fasciculus- Fine touch, pressure and proprioception
Posterior spinocerebellar tract- Proprioceptive signals to cerebellum
Anterior corticospinal tract- Conveys motor signals from precentral gyrus to motor cells within the cord
In which space is a lumbar puncture performed?
A. Subdural space B. Epidural space C. Subarachnoid space D. Extradural space E. Intraventricular space
subarachnoid space
Samples of CSF are normally obtained by inserting a needle into the third and fourth lumbar vertebrae. The tip of the needle lies in the sub arachnoid space, the spinal cord terminates at L1 and is not at risk of injury. Clinical evidence of raised intracranial pressure is a contraindication to lumbar puncture.
Which of the following is not a content of the cavernous sinus?
A. Oculomotor nerve B. Internal carotid artery C. Opthalmic nerve D. Abducens nerve E. Optic nerve
Optic nerve
Mnemonic for contents of cavernous sinus:
O TOM CAT
Occulomotor nerve (III) Trochlear nerve (IV) Ophthalmic nerve (V1) Maxillary nerve (V2) Carotid artery Abducent nerve (VI) T
OTOM=lateral wall components
CA= components within sinus
The optic nerve lies above and outside the cavernous sinus.
