Gray's - Head & Neck - Jackie Flashcards
A 12-year-old boy is admitted to the emergency
department with signs of meningitis. To determine the specific type of meningitis, it is necessary to aspirate cerebrospinal fluid with a lumbar puncture for laboratory examination. However, before performing a lumbar puncture, it must be established that the cerebrospinal fluid pressure is not elevated. What condition in the eye would indicate that cerebrospinal fluid pressure is too
elevated for a lumbar puncture to be performed?
A. Papilledema
B. Separation of the pars optica retinae anterior
to the ora serrata
C. The foveal centralis exhibits hemorrhage from
medial retinal branches.
D. Obvious opacity of the lens
E. Pitting or compression of the optic disc
A. Papilledema is optic disc swelling (“edema
of the papilla”) that is caused by increased intracranial pressure and increased CSF pressure. If a lumbar puncture is performed in a patient with elevated CSF pressure and fluid is withdrawn from the lumbar cistern, the brain can become displaced caudally and the brainstem is pushed against the tentorial notch. This is a potentially fatal complication.
A 65-year-old woman is admitted to the hospital
with signs of cavernous sinus thrombosis. Radiographic examination reveals an aneurysm of the internal carotid artery within the cavernous sinus. During physical examination what sign would one first expect to see if nerve compression has occurred within the cavernous sinus?
A. Inability to gaze downward and medially on
the affected side
B. Complete ptosis of the superior palpebra
C. Bilateral loss of accommodation and loss of
direct pupillary reflex
D. Ipsilateral loss of the consensual corneal
reflex
E. Ipsilateral paralysis of abduction of the pupil
E. Within the cavernous sinus the abducens
nerve is in intimate contact with the internal carotid
artery. Therefore, an aneurysm of the internal carotid artery could quickly cause tension or compression on the abducens nerve. This would result in ipsilateral paralysis of abduction of the pupil
A 54-year-old man is admitted to the emergency
department with a fracture at the frontozygomatic suture. During physical examination the eyelid of the patient exhibits multiple lacerations and the sclera contains small fragments from his broken glasses. What site would be preferable for needle insertion to anesthetize the orbital contents and then the area of the eyelid injury?
A. Into the sclera in the limbic region and also
into the infraorbital foramen
B. Into the lacrimal fossa and also beneath the
lateral bulbar conjunctiva
C. Into the supraorbital foramen and also into
the lacrimal caruncle
D. Through the upper eyelid deeply toward the
orbital apex and also between the orbital septum
and the palpebral musculature laterally
E. Directly posteriorly through the anulus tendineus
and superior orbial fissure
D. It is necessary to anesthetize the conjunctival
covering of the sclera, which is supplied by the
nasociliary branch of the ophthalmic nerve. To do
that, the needle should be placed through the upper eyelid deeply toward the orbital apex to infiltrate the nasociliary nerve, and also between the orbital septum and the palpebral musculature laterally to anesthetize lateral sensory supply from the lacrimal nerve and (perhaps) twigs from the maxillary nerve.
A 55-year old woman has undergone facial surgery
for the excision of a malignant parotid tumor. A
week postoperatively, marked weakness is seen in the musculature of the patient’s lower lip. Which of the following nerves was most likely injured during the parotidectomy?
A. Marginal mandibular branch of facial B. Zygomatic branch of facial C. Mandibular division of the trigeminal nerve D. Buccal branch of facial E. Buccal nerve
A. The anterior division of the facial nerve
passes through the parotid gland and is therefore at risk during surgery of the parotid gland. Since this patient’s symptoms involved paralysis of the muscles of the lower lip, the branch of the facial nerve that supplies these muscles, the marginal mandibular branch, is the one that has suffered the iatrogenic injury.
A 45-year-old male construction worker slips and
falls on a nail protruding from a board. The nail penetrates the skin overlying the submental triangle lateral to the midline. Which of the following muscles would be the last to be penetrated?
A. Platysma B. Mylohyoid C. A nterior belly of he digastric D. Geniohyoid E. Genioglossus
E. During a puncture wound as described in
this case, passing up from below the chin, the nail
would first pierce the platysma, then the anterior
belly of the digastric, then the mylohyoid, then the
geniohyoid, and finally the genioglossus.
A 15-year-old male is admitted to the emergency
department with severe headache and hydrocephalus. Radiographic examination reveals a craniopharyngioma occupying the sella turcica, primarily involving the suprasellar space. Which of the following is the most likely cause of this tumor?
A. Persistence of a small portion of the Rathke
pouch
B. Abnormal development of pars tuberalis
C. Abnormal development of foramina of Monro
D. Abnormal development of the alar plates that
form the lateral wall of diencephalon
E. Abnormal development of diencephalon
A. During embryologic development of the pituitary
gland, an outgrowth from the roof of the pharynx
(Rathke’s pouch) grows cephalad and comprises
the anterior lobe (pars distalis) of the pituitary gland. Since this gland normally occupies the sella turcica, it is most likely a tumor derived from the Rathke’s pouch that is extending up into the sella turcica and the space just above it, the suprasellar space.
A 1-day old infant presents with a telencephalic
vesicle; the eyes are fused, and a single nasal chamber is present in the midline. In addition, the olfactory bulbs and tracts and the corpus callosum are hypoplastic. Which of the following is the most likely diagnosis?
A. Holoprosencephaly B. Smith-Lemli-Opitz syndrome C Schizencephaly D. Exencephaly E Meningoencephalocele
A. In holoprosencephaly, loss of midline structures
results in malformations of the brain and face.
There is a single telencephalic vesicle, fused eyes, and a single nasal chamber. Also, there is often hypoplasia of the olfactory bulbs, olfactory tracts, and corpus callosum.
A 1-day-old infant presents with meningohydroencephalocele. Which of the following bones is most commonly affected?
A. Squamous part of temporal bone B. Petrous part of temporal bone C. Squamous part of occipital bone D. Sphenoid bone E. Ethmoid bone
C. Usually, deficits of the cranium involve the
squamous part of the occipital bone and, in some
cases, the posterior aspect of the foramen magnum. If the herniation or protruding brain includes part of the ventricular system (most likely the posterior horn of the lateral ventricles), then it is referred to as meningohydroencephalocele.
A 1-day-old infant was born with the vault of the
skull undeveloped, leaving the malformed brain exposed. A diagnosis of exencephaly is made. What is the embryologic cause of this condition?
A. Toxoplasmosis infection
B. Failure of closure of the cephalic part of the
neural tube
C. Ossification defect in the bones of the skull
D. Caudal displacement of cerebellar structures
E. Maternal alcohol abuse
B. The rosral neuropore closes during the fourth week of development. If this does not occur, the forebrain primordium is abnormal and the calvaria
or vault fails to develop.
A 6-month-old infant is admitted to the emergency
department with hydrocephalus. Upon physical examination a spina bifi da cystica is noted. Radiographic examination reveals a caudal displacement of the cerebellar structures through the foramen magnum. Which of the following is the most likely diagnosis?
A. A rnold-Chiari malformation B. Holoprosencephaly C. S mith-Lemli-Opitz syndrome D. Schizencephaly E. Exencephaly
B. Holoprosencephaly is caused by failure of
the prosencephalon to properly divide into two cerebral hemispheres. In severe cases this is incompatible with life, but in less severe c ses such as the one presented here, babies have normal or near-normal brain development, sometimes with facial abnormalities. In this case the bnormal development of the forebrain has pushed some of the cerebellum caudally through the foramen magnum, probably due to the
spinabifida cystica.
A 3-month-old infant was admitted to the hospital
because of the parents’ suspicion that the child was deaf. An MRI examination showed abnormal development of the membranous and bony labyrinths, leading the physician to the diagnosis of congenital deafness. Which of the following conditions can lead to congenital deafness?
A. Infection with rubella virus
B. Failure of the second pharyngeal arch to form
C. Failure of the dorsal portion of fi rst pharyngeal
cleft
D. Abnormal development of the auricular
hillocks
E. Failure of the dorsal portion of fi rst pharyngeal
cleft and second pharyngeal arch
A. Congenital deafness is due to a maldevelopment of the conducting system of the middle and external ear or neuroensory structures of the inner ear. Rubella infection during a critical time of ear development can lead to a malformed spiral organ (neurosensory hearing loss) or congenital fixation of the stapes, resulting in conducting hearing loss.
A 3-month-old male infant is brought to the hospital
by his parents because of white patches in his
eyes. An ophthalmoscopic examination shows a congenital cataract. Which of the following conditions can cause a congenital cataract?
A. Infection with rubella virus B. Choroid fissure fails to close C. Persistent hyaloid artery D. Toxoplasmosis infection E. Cytomegalovirus infec ion
A. With congenital cataracts, the lens appears
opaque and grayish white and blindness will result. Infection by teratogenic agents such as rubella virus (German measles) can cause congenital cataracts. This infection can affect the development of the lens, which has a critical period of development between the fourth and seventh week.
A 1-day-old infant who exhibits absence of the
ocular lens is admitted to the pediatric intensive care unit. Laboratory examination reveals a mutation in the PAX6 gene. Which of the following conditions is the most likely diagnosis?
A. Cyclopia B Coloboma C. Anophthalmia D. Aphakia and aniridia E. Microphthalmia
D. A mutation of the PAX6 gene usually results
in congenital aphakia (absence of lens) and
aniridia (absence of iris).
A 2-month-infant presents with small and fl at
maxillary, temporal and zygomatic bones. In addition, the patient has anotia and a dermoid tumor in the eyeball. Which of the following conditions is the most likely diagnosis?
A. Hemifacial microsomia B. Treacher Collins syndrome C. Robin Sequence D. DiGeorge syndrome E. Velocardiofacial syndrome
A. In hemifacial microsomia the craniofacial
anomalies that usually occur involve small and fl at
maxillary, temporal, and zygomatic bones. Ear and
eye anomalies also occur with this syndrome. Ear
abnormalities include tumors and dermoids of the
eyeball.
A 3-month-old infant is diagnosed with abnormal
face, thymic hypoplasia, cleft palate, hypocalcemia, and a ventricular septal defect. Which of the following genes is defective?
A. 22q11 B. SONIC HEDGEHOG C. PAX 2 D. PAX 6 E. 47XXY
A. Abnormal face, cardiac defects, thymic hypoplasia, cleft palate, and hypocalcemia are characteristics of DiGeorge syndrome. A deletion of the long arm of chromosome 22 (22q11) causes this developmental defect.
A 3-day-old male infant has a noticeably small
mandible. A CT scan and physical examinations reveal hypoplasia of the mandible, underdevelopment of the bones of the face, downward-slanting palpebral fissures, defects of the lower eyelids, and deformed external ears. Abnormal development of which of the pharyngeal
arches will most likely produce such symptoms?
A. First arch B. Second arch C. Third arch D. Fourth arch E. Sixth arch
A. The first pharyngeal arch, which is often
associated with the mandible, is responsible for development of Meckel’s cartilage, malleus, incus, and mandible. Additionally, it is innervated by the trigeminal nerve, specifically the mandibular division that innervates the muscles of mastication. This patient presents with features characteristic of developmental defects in the first arch.
A 1-year-old infant is admitted to the hospital
with fever. Radiographic examination reveals a sinus infection. Which of the following sinuses is present at this age?
A. Frontal sinus B. Maxillary sinus C. Sphenoid sinus D. Middle ethmoidal air cells E. Posterior ethmoidal air cells
B. The maxillary sinus arises late in fetal development and is the only sinus present at birth. The frontal and sphenoid sinuses often develop at approximately 2 years of age from the anterior ethmoid air cells and the posterior ethmoid air cells, respectively
A newborn infant presents with severe brain abnormalities. The calvaria is defective and the brain is protruding from the cranium. A rudimentary brainstem and some functioning neural tissue are present. A diagnosis is made of meroencephaly. Which of the following is the most likely cause of this condition?
A. Failure of the rostral neuropore to close in the
fourth week
B. Cytomegalovirus infection
C. Failure of the hypophyseal diverticulum to develop
D. Failure of the neural arch to develop
E. Abnormal neural crest formation
A. Meroencephaly often results from a failure
of the rostral neuropore to close during the fourth
week of development. The calvaria is absent, with a resultant extrusion of the brain from the cranium.
A 55-year-old man is admitted to the emergency
department with fever of 4 days’ duration. Radiographic examination reveals the presence of an infection that is spreading from the retropharyngeal space to the posterior mediastinum. Between which of the following fascial layers are the infections most likely
located?
A. Between alar and prevertebral B. Between alar and pretracheal C. Between pretracheal and prevertebral D. Between buccopharyngeal and alar E. Between buccopharyngeal and prevertebral
Maybe the wrong answer…. reread!
B. The retropharyngeal space extends from the
inferior aspect of the skull to the posterior mediastinum. An infection or abscess in this space could thus travel toward the posterior mediastinum. The retropharyngeal space is enclosed between the visceral fascia covering the posterior wall of the pharynx and the alar layer of the prevertebral fascia. The alar fascia is formed from bilateral anterior extensions of the prevertebral fascia. Between the alar fascia and the more posterior prevertebral fascia covering the skeletal musculature is the so-called danger space of the neck. This space is continuous superiorly to the base of the skull and continues inferiorly through the posterior mediastinum to the level of the respiratory diaphragm. The alar fascia is continuous with the carotid sheath and provides the posterior boundary for the retropharyngeal space. Attachments of the alar fascia to the retropharyngeal fascia result in separation of
the pretracheal space from the retropharyngeal space. The prevertebral fascia invests the vertebral column and the intrinsic muscles of the back. The pretracheal fascia encloses the trachea and larynx, whereas the buccopharyngeal fascia invests the superior pharyngeal constrictor and buccinator muscles.
A 24-year-old man is admitted to the hospital after
a street fight. Radiographic examination reveals an
inferior blow-out fracture of the orbit. Which of the
following nerves is particularly vulnerable to this type of injury?
A. Infraorbital B. Supratrochlear C. Frontal D. Inferior alveolar E. Optic
A. An inferior fracture of the orbit would likely
damage the infraorbital nerve. A blow-out fracture
often results in a displaced orbital wall, and in this
case, the inferior wall. The infraorbital nerve leaves
the skull immediately inferior to the inferior aspect of the orbit, via the infraorbital foramen. Thus, this
nerve is the most likely to be damaged. The frontal
nerve courses superiorly over the orbital contents
before dividing into the supratrochlear and supraorbital nerves. The optic nerve is located behind the eyeball and travels posteriorly away from the orbit to enter the cranium. These nerves are therefore unlikely to be damaged.
A 67-year-old man visits the outpatient clinic
with hearing problems. During physical examination a Rinne test for hearing is performed by placing a tuning fork on his head to test for bone conduction. Upon what specific point should the tuning fork be placed to test conduction?
A. Temporal bone B. Frontal bone C. Mastoid process D. External occipital protuberance E. Vertex of the head
C. The Rinne test is often employed during
physical examination to determine possible conduction hearing loss. A tuning fork is struck and placed on the mastoid process. It is then placed near the external ear until the patient can no longer detect vibrations. In a normal healthy patient the air conduction will be better than the bone conduction. The Rinne test is often used in conjunction with the Weber test to rule out sensoroneural hearing loss.
A 55-year-old man is admitted to the emergency
department with a complaint of pain when chewing over the previous 3 months. Physical examination reveals the patient suffers from odynophagia and some hoarseness in his speech. Radiographic examination reveals a tumor at the tracheoesophageal groove. Which of the following
nerves is most likely affected by the tumor?
A. Recurrent laryngeal B. Internal laryngeal C. Vagus D. External laryngeal E. Phrenic
A. The right and left recurrent laryngeal nerves
loop around he right subclavian artery and the arch
of the aorta, respectively These nerves then travel
superiorly in the tracheoesophageal groove to the larynx. Damage to the recurrent laryngeal as a result of surgical intervention or the presence of a tumor in the tracheoesophageal groove would render the patient hoarse. This hoarseness is due to a lack of innervation by the recur ent laryngeal nerve to most of the muscles of the larynx. Damage to the internal laryngeal nerve would cause a loss of sensation above the vocal
cords, in addition to a loss of taste on the epiglottis. Damage to the external laryngeal, which can occur during thyroidectomy, will result in a loss of innervation to the cricothyroid muscle, with resultant vocal weakness. Patients with this lesion will often present with a fatigued voice. The vagus nerve gives rise to the recurrent laryngeal nerves; damage to this nerve, however, would result in numerous symptoms beyond just hoarseness.
A 34-year-old man is admitted to the emergency
department after falling off his motorbike, suffering an injury to his head. The patient has multiple lacerations in the skin over the frontal bone. Which of the following veins could most likely provide a pathway of transmission of infection from the veins of the scalp to the underlying dural venous sinuses?
A. Supratrochlear vein B. Diploic veins C. Anterior cerebral veins D. Superior sagittal sinus E. Supraorbital vein
B. Diploic veins are responsible for communication
between the veins of the scalp and the venous
sinuses of the brain. Diploic veins are situated within the layers of bone of the skull and connect the emissary veins of the scalp to the venous sinuses located between two layers of dura The diploe are of clinical significance in that the diploic veins within this layer provide a pathway of communication between the veins of the scalp and underlying venous sinuses of the brain, by means of emissary veins The emissary veins and diploe provide a potential vascular pathway
of infection
A 65-year-old man is admitted to the emergency
departmen after an episode of a transient ischemic attack. Radiographic examination reveals an aneurysm in the region between the posterior cerebral artery and superior cerebellar artery. Which of the following nerves will most likely be compressed from the aneurysm?
A. Trochlear B. Abducens C Oculomotor D. Vagus E Optic
C. The oculomotor nerve passes between the
posterior cerebral artery (PCA) and the superior cerebellar artery near the junction of the midbrain and pons.
A 36-year-old female racquetball player is admitted to the hospital after being struck in the orbital region. Radiographic examination reveals a blow-out fracture of the medial wall of the orbit. Physical examination also reveals that the pupil of the affected eye cannot be turned laterally. Which of the following muscles is most likely injured or trapped?
A. Lateral rectus B. Medial and inferior recti C. Medial rectus D. Medial rectus and superior oblique E. Inferior rectus
C. A blow-out fracture of the medial wall of the
orbit would likely render the medial rectus nonfunctional by entrapment of the muscle between the edges of the cracked medial wall. The medial rectus is responsible for adduction of the eye, but in this case the muscle acts as a tether or anchor on the eyeball, preventing lateral excursion (abduction) of the eye. There is no nerve damage here, and the muscle is not paralyzed.
A 16-year-old female volleyball player is admitted
to the hospital after being hit in the eye with a ball
spiked at the net. Radiographic examination reveals a blow-out fracture of the inferior wall of the orbit. Physical examination also reveals that the pupil of her eye cannot be turned upward. Which of the following muscles is (are) most likely injured?
A. Inferior rectus and inferior oblique B. Medial and inferior recti C. Inferior oblique D. Medial rectus, inferior rectus, and inferior oblique E. Inferior rectus
A. The inferior rectus and inferior oblique
muscles are entrapped in the crack between the parts of the fractured orbital floor. Normally, the superior rectus and the inferior oblique are responsible for an upward movement of the eyeball. In this case, however, the broken orbital plate of the maxilla has snared or entrapped the inferior rectus and inferior oblique muscles, causing them to act as anchors on the eyeball, preventing upward movement of the eye. The muscles are not necessarily damaged, nor is there
any nerve injury in this patient. Freeing the muscles
from the bone will allow free movement of the eye
again, barring any other injury.
A 36-year-old man is admitted to the emergency
department with a painful skin rash on the dorsum of his nose. Physical examination reveals that a herpetic lesion is affecting the dorsum of the nose and the eyeball. Which of the following nerves is most likely to be responsible for transmission of the virus to the eye?
A. Nasociliary B. Supratrochlear C. Infraorbital D. P osterior ethmoidal E. A nterior ethmoidal
A. A herpes rash on the dorsum of the nose is
known as Hutchinson’s sign. This indicates that the virus is located in cell bodies of the ophthalmic division of the trigeminal nerve. This nerve branche into nasociliary, frontal and lacrimal branches. The nasociliary nerve has direct branches th t carry sensory innervation from the eye. The nasociliary nerve also gives off the ethmoidal nerves that innervate the superior nasal mucosa, in addition to providing the origin of the dorsal nasal nerve.
