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Flashcards in Head and neck I Deck (43)
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1
Q

Inferior Alveolar nerve

A

The inferior alveolar nerve, a branch of the mandibular division of the trigeminal nerve (V), traverses the inferior alveolar, or dental, canal of the mandible to supply all the teeth of that hemimandible; all the teeth on that side are therefore anaesthetised. The mental branch of the nerve emerges through the mental foramen to supply the lower lip, which becomes numb in a successfully performed block. The muscles of the tongue, of mastication and of facial expression are not affected

2
Q

a total division of the left facial (VII) nerve. Postoperatively, which is the most likely sequel

A

Tendency for food and fluids to collect in the buccal sulcus after meals. The facial nerve supplies all the muscles needed for facial expression including the occipitofrontalis, which wrinkles the forehead. A distressing feature is paralysis of the buccinator muscle, which acts to empty the buccal sulcus during mastication. There are no cutaneous sensory fibres in the facial nerve. The levator palpebrae superioris is supplied by the oculomotor nerve, so the patient can still raise his upper lid. The chorda tympani fibres, which transmit taste from the anterior two-thirds of the tongue, pass from the lingual nerve to the facial nerve just below the skull, and therefore remain intact in peripheral injuries of the facial nerve

3
Q

patient undergoes excision of the left submandibular salivary gland for sialectasia. Unfortunately, his hypoglossal (XII) nerve on that side is damaged.

A

The hypoglossal nerve supplies all the muscles of the tongue but none of the palate (the palatoglossus muscle, supplied by the vagus nerve, is a muscle of the palate). It has no sensory component. The genioglossus muscle protrudes the tongue; when it is paralysed, the muscle on the opposite side is unaffected and deviates the tongue towards the affected side

4
Q

inferior laryngeal nerve

A

The inferior or recurrent laryngeal branch of the vagus nerve (X) supplies motor fibres to all the muscles of the larynx apart from the cricothyroid muscle, and sensory fibres to the larynx inferior to the vocal cords. Injury to this nerve will result in paralysis of all muscles of the larynx except cricothyroid, and paralysis of the vocal cord. Paralysed vocal cords lie in the “paralytic position”, slightly abducted from the midline, and do not move with phonation. The sensory loss from this nerve injury will be inferior to the vocal cords on the affected side. Cricothyroid is supplied by the superior laryngeal branch of the vagus nerve

5
Q

a septic cavernous sinus thrombosis, with high fever, orbital oedema and proptosis. The primary source of infection would most likely arise from which site?

A

The cavernous sinus lies on either side of the body of the sphenoid. Anteriorly, the ophthalmic veins drain into the sinus and communicate with the anterior facial vein, which drains the face and upper lip – hence the danger of spread of infection from this locus.

6
Q

A 54-year-old woman presents with longstanding tinnitus and evidence of a unilateral fifth (trigeminal nerve) palsy. Her MRI scan shows evidence of an acoustic neuroma. Where is compression of the trigeminal nerve most likely to be occurring?

A

A complete fifth nerve lesion causes unilateral sensory loss on the face, tongue and buccal mucosa. When motor fibres are damaged there is deviation of the jaw to the side of the lesion as the mouth is opened. Loss of the corneal reflex may be an early indication of a fifth nerve lesion.
Brainstem lesions involving the fifth nerve nuclei may include brainstem glioma, multiple sclerosis, brainstem infarction or syringobulbia. Lesions at the cerebellopontine angle resulting in fifth nerve damage may include acoustic neuroma, meningioma and secondary tumour deposits. Within the cavernous sinus, the trigeminal ganglion may be compressed by a pituitary tumour extending into the sinus, internal carotid artery aneurysm, cavernous sinus thrombosis or secondary tumour. The trigeminal ganglion may also be affected by herpes zoster infection. Prognosis for the recovery of trigeminal nerve function is dependent on the underlying cause.

7
Q

the inferior laryngeal branch of the right recurrent laryngeal nerve was injured.The action of which of the following laryngeal muscles is most likely to be affected

A

The posterior cricoarytenoid is innervated by the inferior laryngeal nerve, which is a continuation of the recurrent laryngeal nerve. The posterior cricoarytenoid is the only muscle that abducts the vocal folds. If this muscle is denervated, the vocal folds may be paralysed in an adducted position, which would prevent air from entering the trachea. Arytenoid, lateral cricoarytenoid and thyroarytenoid all adduct the vocal folds. Cricothyroid is the only laryngeal muscle innervated by the external branch of the superior laryngeal. It tenses the vocal ligaments by tipping the thyroid cartilage forward relative to the cricoid cartilage

8
Q

The vocal ligaments

A

The vocal folds are concerned with the production of sound and enclose two strong bands, the vocal ligaments. Each ligament consists of a band of yellow elastic tissue formed by the superior free edge of the conus elasticus, attached in front to the angle of the thyroid cartilage and behind to the vocal process of the arytenoid. Its lower border is continuous with the thin lateral part of the conus elasticus. Its upper border forms the lower boundary of the ventricle of the larynx. Laterally, the vocalis muscle lies parallel with it. It is covered medially by mucous membrane, which is extremely thin and closely adherent to its surface.

9
Q

supratrochlear nerve

A

The supratrochlear nerve, the smaller of the two branches of the frontal nerve, passes above the pulley of the superior oblique and gives off a descending filament to join the infratrochlear branch of the nasociliary nerve. It then escapes from the orbit between the pulley of the superior oblique and the supraorbital foramen, curves up onto the forehead close to the bone, ascends beneath the corrugator and frontalis and dividing into branches which pierce these muscles, it supplies the skin of the lower part of the forehead close to the midline and sends filaments to the conjunctiva and skin of the upper eyelid.

10
Q

Facial muscles

A

The facial muscles are subcutaneous (just under the skin, in the same plane as the platysma) muscles that control facial expression. They generally originate on bone and insert on the skin of the face. The facial muscles are innervated by cranial nerve VII, also known as the facial nerve. The facial muscles are derived from the second pharyngeal arch.

11
Q

olfactory foramina

A

The olfactory foramina are located in the anterior cranial fossa. These foramina are in the cribriform plate of the ethmoid bone for the passage of olfactory nerves.

12
Q

Inferior sagittal sinus

A

The inferior sagittal sinus is enclosed in the posterior half or two thirds of the free margin of the falx cerebri. It is cylindrical in shape. It increases in size as it passes backward and ends in the straight sinus. It receives several veins from the falx cerebri and occasionally receives a few veins from the medial surfaces of the hemispheres.

13
Q

separates the anterior and posterior chambers in the eye

A

iris has received its name from its various colours in different individuals. It is a thin, circular, contractile disc, suspended in the aqueous humour between the cornea and lens and perforated a little to the nasal side of its centre by a circular aperture, the pupil. At its periphery it is continuous with the ciliary body and is also connected to the posterior elastic lamina of the cornea by means of the pectinate ligament. Its surfaces are flattened and look forward and backward, the anterior toward the cornea, the posterior toward the ciliary processes and lens. The iris divides the space between the lens and the cornea into an anterior and a posterior chamber. The anterior chamber of the eye is bounded in front by the posterior surface of the cornea; behind by the front of the iris and the central part of the lens. The posterior chamber is a narrow chink behind the peripheral part of the iris and in front of the suspensory ligament of the lens and the ciliary processes. In the adult, the two chambers communicate through the pupil, but in the fetus up to the seventh month they are separated by the membrana pupillaris

14
Q

A patient who had surgery in the left carotid triangle complained to his physician that he has little sense of touch to the skin over the left side of his neck and difficulty swallowing. The patient’s hyoid bone is deviated to the right side. The patient’s tongue is not affected. The physician suspects that the cervical plexus of nerves to the left side of this patient’s neck was harmed during the surgical procedure

A

The ansa cervicalis (or ansa hypoglossi in older literature) is a loop of nerves that are part of the cervical plexus. Branches from the ansa cervicalis innervate the sternohyoid, sternothyroid and the inferior belly of the omohyoid. Two roots make up the ansa cervicalis. The superior root of the ansa cervicalis is formed by a branch of spinal nerve C1. These nerve fibres travel in the hypoglossal nerve before leaving to form the superior root. The superior root goes around the occipital artery and then descends embedded in the carotid sheath. It sends a branch off to the superior belly of the omohyoid muscle and is then joined by the inferior root. The inferior root is formed by fibres from spinal nerves C2 and C3

15
Q

Postganglionic sympathetic fibres innervating the dilator pupillae muscle begin in….

A

The cervical portion of the sympathetic trunk consists of three ganglia, named according to their positions as the superior, middle and inferior ganglia and connected by intervening cords. This portion receives no white rami communicantes from the cervical spinal nerves. Its spinal fibres are derived from the white rami of the upper thoracic nerves and enter the corresponding thoracic ganglia of the sympathetic trunk, through which they ascend into the neck. The superior cervical ganglion, the largest of the three, is located opposite the second and third cervical vertebrae. It is reddish-grey in colour and usually fusiform in shape. It is thought to be formed by the coalescence of four ganglia, corresponding to the upper four cervical nerves. It is related anteriorly to the sheath of the internal carotid artery and the internal jugular vein and posteriorly to the longus capitis muscle. It contains neurones that supply sympathetic innervation to the face (including the dilator pupillae muscle of the iris

16
Q

The ophthalmic artery emerges through which of the following foramina to reach the eye?

A

The ophthalmic artery arises from the internal carotid, just as that vessel is emerging from the cavernous sinus, on the medial side of the anterior clinoid process and enters the orbital cavity through the optic foramen (canal), below and lateral to the optic nerve. It then passes over the nerve to reach the medial wall of the orbit and thence horizontally forward, beneath the lower border of the superior oblique and divides it into two terminal branches, the frontal and dorsal nasal. As the artery crosses the optic nerve it is accompanied by the nasociliary nerve and is separated from the frontal nerve by the rectus superior and levator palpebrae superioris

17
Q

The sphenopalatine artery

A

The sphenopalatine artery, a branch of the third part of the internal maxillary artery, passes through the sphenopalatine foramen into the cavity of the nose, at the back part of the superior meatus. Here it gives off its posterior lateral nasal branches, which spread forward over the conchae and meatuses, anastomose with the ethmoidal arteries and the nasal branches of the descending palatine and assist in supplying the frontal, maxillary, ethmoidal and sphenoidal sinuses. Crossing the undersurface of the sphenoid, the sphenopalatine artery ends on the nasal septum as the posterior septal branches; these anastomose with the ethmoidal arteries and the septal branch of the superior labial. One branch descends in a groove on the vomer to the incisive canal and anastomoses with the descending palatine artery

18
Q

The submandibular duct opens

A

The submandibular duct (Wharton’s duct) is about 5 cm long and its wall is much thinner than that of the parotid duct. It begins from numerous branches from the deep surface of the gland and runs forward between the mylohyoid and the hyoglossus and genioglossus, then between the sublingual gland and the genioglossus and opens by a narrow orifice on the summit of a small papilla, at the side of the frenulum linguae, near the midline in the anterior aspect of the floor of the mouth. On the hyoglossus it lies between the lingual and hypoglossal nerves, but at the anterior border of the muscle it is crossed laterally by the lingual nerve. The terminal branches of the lingual nerve ascend on its medial side.

19
Q

Of the following intrinsic muscles of the larynx, which tenses (stretches) the vocal folds?

A

The cricothyroid, triangular in form, arises from the front and lateral part of the cricoid cartilage; its fibres diverge and are arranged in two groups. The lower fibres constitute a pars obliqua and slant backward and lateralward to the anterior border of the inferior cornu. The anterior fibres, forming pars recta, run upward, backward and lateralward to the posterior part of the lower border of the lamina of the thyroid cartilage. The external laryngeal branch of the superior laryngeal nerve supplies the cricothyroid. The cricothyroids produce tension and elongation of the vocal folds by drawing up the arch of the cricoid cartilage and tilting back the upper border of its lamina. The distance between the vocal processes and the angle of the thyroid is so increased and the folds are consequently elongated.

20
Q

The nasolacrimal duct empties into the:

A

The nasolacrimal duct is a membranous canal, about 18 mm in length, which extends from the lower part of the lacrimal sac to the inferior meatus of the nose, where it ends by a somewhat expanded orifice, provided with an imperfect valve, the plica lacrimalis (Hasner’s fold), formed by a fold of the mucous membrane. It is contained in an osseous canal, formed by the maxilla, the lacrimal bone and the inferior nasal concha. It is narrower in the middle than at either end and is directed downward, backward and a little lateralward. The mucous lining of the lacrimal sac and nasolacrimal duct is covered with columnar epithelium, which in places is ciliated

21
Q

In surgery of the thyroid gland, the external laryngeal nerve may be injured and must be identified before ligating the:

A

The external laryngeal nerve is the smaller, external branch (ramus externus) of the superior laryngeal nerve. It descends on the larynx, beneath the sternothyroid muscle, to supply the cricothyroid muscle. It gives branches to the pharyngeal plexus and the superior portion of the inferior pharyngeal constrictor and communicates with the superior cardiac nerve behind the common carotid artery. The external branch is susceptible to damage during thyroidectomy, as it lies immediately deep to the superior thyroid artery.

22
Q

Directing the gaze downward when the eye is abducted requires the:

A

The inferior rectus muscle is an extraocular muscle that depresses, adducts and rotates the eye laterally. As with most of the muscles of the orbit (exceptions are the lateral rectus and superior oblique), it is innervated by the oculomotor nerve (cranial nerve III)

23
Q

What structure divides the posterior triangle of the neck further into an upper and lower triangle?

A

The posterior triangle is bounded in front by the sternocleidomastoid; behind, by the anterior margin of the trapezius; its base is formed by the middle third of the clavicle; its apex, by the occipital bone. The space is crossed, about 2.5 cm above the clavicle, by the inferior belly of the omohyoid, which divides it into two triangles, an upper or occipital and a lower or subclavian. It contains the accessory nerve, which crosses the triangle from the upper third of sternocleidomastoid to the lower two-thirds of trapezius. It is particularly vulnerable to damage during lymph node biopsy, when damage results in an inability to shrug the shoulders or raise the arm above the head (brushing hair).

24
Q

The thyroid gland in some cases can have a thyroidea ima artery that supplies the isthmus of the thyroid. If present, it would take origin:

A

The thyroidea ima artery, when present, arises from the brachiocephalic trunk (innominate artery) and ascends in front of the trachea to the lower part of the thyroid gland, which it supplies. It varies greatly in size and appears to compensate for deficiency or absence of one of the other thyroid vessels. It occasionally arises from the aorta, the right common carotid, the subclavian or the internal mammary.

25
Q

The name of the bone that the internal carotid artery enters to reach the intracranial cavity is the:

A

The internal carotid artery supplies the anterior part of the brain, the eye and its appendages and the forehead and nose. In the adult it is the same size as the external carotid, but in the child it is larger than the external carotid. It is remarkable for the number of curvatures that it presents in different parts of its course. It occasionally has one or two curvatures near the base of the skull, while in its passage through the carotid canal in the petrous part of the temporal bone and along the side of the body of the sphenoid bone it describes a double curvature and resembles an italic letter ‘s’. The carotid canal is found on the inferior surface of the petrous part of the temporal bone. It ascends vertically at first and then bends and runs horizontally forward and medially. It transmits the internal carotid artery and the carotid plexus of nerves into the cranium.

26
Q

A 25-year-old woman with history of high-grade fever, gradual-onset loss of consciousness and a petechial rash is suspected of having bacterial meningitis. As part of the diagnostic procedure, a lumbar puncture is to be performed. To avoid injury to the spinal cord and nerves you must insert the spinal needle just below the spine of the fourth lumbar vertebra.What anatomical landmark would you use to identify the spine of the fourth lumbar vertebra

A

The fourth lumbar vertebra (L4) is a relatively safe level for performing a lumbar puncture. Since the conus medullaris is at the inferior border of L1 or the superior border of L2, it should be safe to insert a needle either above or below L4. The anatomical landmark used to identify L4 is the top of the iliac crest. The line connecting the top of the two iliac crests, the supracrestal line, passes through the spinous process of the L4 vertebra. Therefore, by finding the tops of the iliac crests, you should be able to identify L4.

27
Q

An 85-year-old man with prostatic cancer is most likely to have metastatic spread of cancer through which of the following veins?

A

The veins of the internal vertebral venous plexus are clinically significant because they are valveless and can serve as a route for metastases. Cancerous cells can travel freely in vertebral veins and lodge somewhere else in the body. The other veins all have valves that would direct the flow of blood and stop some of the metastatic spread.

28
Q

Itching sensation from the skin immediately over the base of the spine of your scapula is mediated through the:

A

Dorsal and ventral primary rami are the first branches off spinal nerves. Dorsal rami provide sensory innervation to the skin over the back and give motor innervation to the true back muscles; ventral rami supply sensory innervation to the skin over the limbs and the skin over the ventral side of the trunk. Ventral rami also give motor innervation to the skeletal muscles of the neck, trunk and extremities. Therefore, if the skin over the spine of your scapula began to itch, the sensation of that area would be transmitted by the dorsal primary ramus of C7. The accessory nerve, which innervates the trapezius, is not responsible for any sensory innervation. The dorsal and ventral roots of spinal nerves are not directly responsible for any sensory innervation to the skin. Dorsal and ventral rootlets emerge from the spinal cord to form the dorsal and ventral roots. The ventral roots contain efferent motor fibres to skeletal muscles, while the dorsal roots contain afferent sensory fibres. These roots combine to form the spinal nerve, which then gives off the primary rami.

29
Q

Which of the following effects is most likely to be seen if the right dorsal scapular nerve is injured near its origin?

A

The dorsal scapular nerve is a motor nerve off the C5 nerve root that innervates the rhomboids and levator scapulas. These muscles help to retract and elevate the scapula, so these movements would be weakened following that damage. The skin of the upper back on the right side is innervated by the dorsal primary rami of a spinal nerve. The point of the right shoulder, the acromion, is elevated by the trapezius. The trapezius is innervated by the accessory nerve, so the point of the shoulder would droop if the accessory nerve was damaged. Latissimus dorsi, innervated by the thoracodorsal nerve, allows for extension and adduction of the arm.

30
Q

The transverse cervical artery is severed in a road traffic accident. Which muscle would be affected the most?

A

The transverse cervical artery supplies blood to the trapezius. Levator scapulas and the rhomboids receive blood from the dorsal scapular artery. Latissimus dorsi receives blood from the thoracodorsal artery

31
Q

Which of the following statements regarding the spinal arachnoid mater is CORRECT?

A

The spinal part of the arachnoid is a thin, delicate, tubular membrane loosely investing the spinal cord. Above, it is continuous with the cranial arachnoid. Below, it widens out and invests the cauda equina and the nerves proceeding from it. It is separated from the dura mater by the subdural space, but here and there this space is traversed by isolated connective-tissue trabeculae, which are most numerous on the posterior surface of the spinal cord. The arachnoid surrounds the cranial and spinal nerves and encloses them in loose sheaths as far as their points of exit from the skull and vertebral canal. The arachnoid consists of bundles of white fibrous and elastic tissue intimately blended together. Its outer surface is covered with a layer of low cuboidal mesothelium. The inner surface and the trabeculae are likewise covered by a somewhat low type of cuboidal mesothelium, which in places is flattened to a pavement type. Vessels of considerable size, but few in number, and a rich plexus of nerves derived from the motor root of the trigeminal, the facial and the accessory nerves, are found in the arachnoid.

32
Q

Each branchial (pharyngeal) arch has a cartilaginous bar, a muscle component that differentiates from the cartilaginous tissue, an artery and a cranial nerve. The first pharyngeal (branchial) arch:

A

The first pharyngeal arch or mandibular arch is involved with development of the face. It develops two processes, maxillary and mandibular, which form the upper and lower jaws respectively. Bones and muscles of this region are developed from mesoderm in the arch. Meckel’s cartilage is the first arch cartilage. It ossifies to form the malleus and incus in the middle ear. The sphenomandibular ligament is derived from its perichondrium. The rest of the cartilage disappears after the mandible forms around it by intramembranous ossification. The muscles derived from the first arch include temporalis, masseter, medial and lateral pterygoids, anterior belly of the digastric, mylohyoid, tensor tympani and tensor palati. The trigeminal nerve is the motor supply of the mandibular arch

33
Q

A 47-year-old male with a history of alcoholic liver disease presents with a two week history of epigastric pain and bloating. Computerised tomography (CT) reveals a 4cm fluid collection in the lesser sac.

A

Pancreatic pseudocysts are a complication of both acute and chronic pancreatitis. The incidence of all three is increased in patients with alcoholic liver disease. They usually develop within the lesser sac, and so can be drained via a posterior wall gastrostomy at endoscopy. Von-Hippel Lindau disease is a rare inherited pathology that causes cyst development in multiple organs, including the pancreas.

34
Q

A 20-year-old girl presented with a unilateral conductive hearing loss; otoscopy revealed characteristics of Cholesteatoma of the middle ear.

A

Cholesteatoma derived its name from early observations that it resembled a ball of cholesterol. Although given the suffix –oma, it does not behave like a tumour, nor is it composed of atypical cells suggestive of a tumour. It is in fact a non-cleaning squamous cell cyst that can cause complications if untreated, due to its invasive properties, including meningitis, brain abscess, hearing loss, neck abscess (Bezold’s abscess, very rare), lateral sinus thrombosis, facial nerve palsy and vertigo. It usually presents with continuously discharging ears and otalgia. Treatment is regular cleaning and exteriorisation in the form of mastoidectomy and variations of this procedure.

35
Q

An 18-year-old female presented with ear-ache, a conductive deafness and a temperature of 39oC

A

The most common causes of conductive deafness include wax, acute otitis media, secretory otitis media, chronic otitis media, barotrauma, otosclerosis and injuries to the tympanic membrane and otitis externa. Other less common causes include tumours of the middle ear and traumatic ossicular dislocation. Sensory neural deafness is caused by a number of causes including infections such as mumps, herpes zoster, meningitis and syphilis. Other causes include congenital–maternal rubella, cytomegalovirus, toxoplasmosis, prolonged exposure to loud noises, drugs (aspirin, aminoglycosides), Meniere’s disease, head injury and acoustic neuroma. Metabolic causes include diabetes and hypothyroidism. In Paget’s disease there may be a mixed hearing loss ie conduction and sensorineural deafness. This is due to direct involvement of the ossicles of the inner ear due to ankylosis of the stapes, or by impeachment of bone on the eighth cranial nerve in the auditory foramen

36
Q

A 76-year-old man underwent tracheostomy for long term ventilation. A few weeks later the tube was removed but the patient had hoarseness of voice

A

Other complications include pneumothorax, dislodgement of the tube (partial or complete), obstruction of the tube or trachea, tracheal stenosis, sepsis, cuff prolapse, intubation granuloma of the vocal cords. Subglottic stenosis occurs if the first and second tracheal rings are damaged.

37
Q

A 69-year-old man presents with recurrent episodes of epistaxis.

A

Epistaxis most commonly arises from the anterior part of the septum – Little’s area. Hypertensive epistaxis affects an older age group and arises far back or high up the nose. It may require nasal/post-nasal packing. Nasal packing is performed using 1-inch ribbon gauze soaked in 5% cocaine and adrenaline (1/1000). Surgical treatment is rarely necessary and SMR is used if bleeding is from behind a septal spur or if deviation prevents packing.

38
Q

A 29-year-old female underwent total thyroidectomy. Post-operatively she complained of difficulty in breathing. What would be the most likely cause of this?

A

A thyroid crisis should be suspected if there is tachycardia, hyperpyrexia and confusion. It is a potentially life-threatening condition that is rarely seen but classically occurs in a patient who has undergone surgery without adequate preoperative preparation. Assessment of damage to the external superior laryngeal nerve is difficult, as changes are subtle. It is most likely to be damaged at the time of ligation and division of the superior thyroid vessels. To avoid this, arterial branches should be ligated individually and close to the thyroid and the nerve identified whenever possible. Persistent hypoparathyroidism should be less than 1% in reputable units.

39
Q

A 27-year-old is brought into Accident & Emergency by ambulance following a high speed road traffic accident. What is the best method to immobilise his cervical spine?

A

The cervical spine must be immobilised in all unconscious victims of trauma, those with blunt injury above the clavicle and those with multisystem trauma. The neck is initially immobilised manually in the in-line position NOT with traction. The head and neck may be carefully moved into the in-line position if found in a different position, however if any resistance is encountered it is then immobilised in the position that it was found. For immobilisation to be adequate a collar, sandbags and tape must all be used.

40
Q

A 25-year-old motorcyclist sustains a head injury and presents with a Glasgow Coma Score of 10. He has no other complications. What should the initial investigations of this patient include?

A

Plain radiographs of the chest, pelvis and cervical spine should be performed in all patients with a significant head injury who are unconscious and so cannot be assessed reliably. The insertion of an intracranial pressure (ICP) monitor is indicated for diffuse axonal injuries where patients are managed conservatively, persistent raised ICP and in the presence of systemic complications, such as severe hypotension and hypoxia. Lumbar puncture is contraindicated in patients with raised ICP due to the risk of coning.

41
Q

Skull fractures in the temporal region can damage the middle meningeal artery. Which of the following best describes this artery?

A

The middle meningeal artery is a branch of the maxillary artery which in turn is a branch of the external carotid artery. The middle meningeal artery lies on the bone outside the dura and passes through the foramen spinosum. The foramen ovale transmits the accessory middle meningeal artery.

42
Q

An 82-year-old woman fainted and fell downstairs sustaining head injuries with skull fracture. Bleeding was discovered from the middle meningeal artery.What is this is associated with?

A

The anterior branch is more often affected than the posterior, probably because it courses through thinner bone and across the sutures at the pterion. Although designated an extradural bleed, the haematoma collects between the endosteal and meningeal layers of the dura mater. Fractures invariably precede an extradural bleed. The pia mater invests the blood vessel, not the arachnoid mater.

43
Q

In head anatomy, the middle meningeal artery could be ruptured in head trauma.

A

The middle meningeal artery is a branch of the maxillary artery in the infratemporal fossa. The maxillary artery enters the infratemporal fossa before running forwards between the heads of lateral pterygoid passing into the pterygopalatine fossa. The middle meningeal artery passes through the foramen spinosum. The dura mater is supplied by the posterior meningeal artery.