Perez Ch 35: Imaging and Anatomy

Question 1

Images are displayed within a matrix composed of voxels, each representing a
volume of radiodensity that is quantified by a linear attenuation value called a
Hounsfield unit (HU). Each voxel is assigned an HU in the range of −1,000 to
1,000 corresponding to a shade of gray that represents the attenuation difference
between a given material and water

Answer 1

air is the least dense
material with an HU value of −1,000, whereas water has an HU value of 0. Soft
tissues have a range of attenuation with typical HU values as follows: fat (−120),
blood (30), muscle (40), and bone (>300).

Question 2

IV contrast agents are excreted through the kidneys, are nephrotoxic, and are
not typically administered to patients with impaired renal function

Answer 2

glomerular
filtration rate [GFR] < 60, creatine [Cr] < 2.0, though institutional policies vary

Question 3

TR and TE dramatically affect image
contrast and determine which tissue properties are selected. T1-weighted images,
in which fluid is dark and fat is bright, are generally good at depicting anatomy;
T1-weighted images are generated by selecting

Answer 3

short TR (typically ≤800 ms) and
short TE values (≤30 ms).

Question 4

T2-weighted images, in which fluid is bright and fat is
dark, are fluid-sensitive and can depict areas of pathology; T2-weighted images
are generated by selecting

Answer 4

long TR (≥2,000 ms) and long TE values (≥60 ms)

Question 5

The central nervous system consists of the brain and spinal cord. Both are
covered with three meningeal layers—the dura mater, arachnoid mater, and pia
mater. Meningiomas are the most common tumors arising from the meninges.
They arise from ________ but are typically affixed to the underside of the
dura mater

Answer 5

arachnoid cells

Question 6

The arachnoid mater and pia mater are considered the ______with the
intervening space (subarachnoid space) filled with cerebrospinal fluid (CSF).

Answer 6

leptomeninges

Question 7

Leptomeningeal
involvement occurs most frequently with

Answer 7

pediatric brain tumors (e.g.,
medulloblastoma), acute lymphoblastic leukemia, and some solid cancers (e.g.,
breast cancer, melanoma, and lung cancer in particular).

Question 8

The
diencephalon includes the ____

Answer 8

thalamus, hypothalamus, and third ventricle

Question 9

originates in the ventral aspect of the brainstem, ascends on the clivus, and
crosses the internal carotid artery near the superior aspect of foramen lacerum
before entering the cavernous sinus. It then exits the skull through the superior
orbital fissure.

Answer 9

CN VI

Question 10

The motor and sensory nerve roots of CN V exit the pons and
pass underneath the free edge of the tentorium cerebelli into the Meckel cave,
forming the trigeminal (gasserian) ganglion. From the ganglion, V1 and V2 enter
the cavernous sinus and subsequently exit the skull through the ______ respectively. V3 exits the skull through foramen
ovale.

Answer 10

superior orbital
fissure and foramen rotundum,

Question 11

Four cranial nerves, including two branches of CN V, pass
through the cavernous sinus. Within the sinus, _____) is
located most superiorly, whereas the ____
) is located most
inferiorly.

Answer 11

the oculomotor nerve (CN III
maxillary nerve (CN V2

Question 12

The anterior skull base includes the cribriform plate (consisting of portions of the frontal and ethmoid bones), which is perforated by branches of the _____ and roofs of the orbits (formed from portions of the frontal and sphenoid bones). The central portion of the sphenoid bone, the basisphenoid, contains the sella turcica. The basisphenoid and basiocciput are joined by a spheno-occipital synchondrosis, which eventually fuses and forms a structure known as the clivus. Between the basisphenoid and the lesser wing of the sphenoid bone is the optic canal ______ and between the basisphenoid and the greater wing of the sphenoid is the superior orbital fissure _______. Within the greater wing of the sphenoid bone is an anteriorly directed canal known as the foramen rotundum ______(, and an inferiorly directed canal known as the foramen ovale. Posterolateral to the foramen ovale is the foramen spinosum, which carries the _______

Answer 12

(cranial nerve [CN] I)
(carrying CN II),
(carrying CN III, IV, V1, and VI)
carrying V2)
middle meningeal artery.

Question 13

Within the petrous temporal bone is the internal auditory canal, which carries _____ Between the portion of the temporal bone containing the inner ear and the clivus is the apex of the petrous temporal bone, a structure that can occasionally be pneumatized

Answer 13

CN VIII to the structures of the inner ear and acts as a conduit for the facial nerve (CN VII).

Question 14

The jugular foramen is located between the petrous and mastoid portions of the temporal bone and the occipital bone, and carries the jugular bulb, which is the transition between the sigmoid sinus and the internal jugular vein. The jugular foramen is parcellated into the posterior pars vascularis ______, and the smaller anteromedial pars nervosa ______ Within the exoccipital portion of the occipital bone are the hypoglossal canals, carrying the _____

Answer 14

(carrying CN X and XI)
(carrying CN IX).
right and left hypoglossal nerve (CN XII).

Question 15

The vertebral column typically consists of _____

Answer 15

33 bones (7 cervical, 12 thoracic, 5
lumbar, 5 sacral, and 4 coccygeal).

Question 16

In adults, the spinal
cord typically ends at the _____interspace (termed the conus medullaris). In an
infant, the spinal cord terminates at L2 or L3. However, the spinal nerves
continue to descend within the spinal canal (termed the ______).

Answer 16

L1-2
cauda equina

Question 17

The subarachnoid space, containing CSF, typically extends to the _____. At this level, the meninges fuse together and extend caudally as
the_____ which anchors the spinal cord to the coccyx.

Answer 17

second sacral vertebral body
filum terminale,

Question 18

The hallmark
spectroscopic pattern of brain tumors is an increase in ___-containing
compounds and a decrease in ___relative to normal brain tissue

Answer 18

Cho
NAA

Question 19

Neck Node Level II is subdivided into anterior (level IIA) and posterior (level IIB)
regions, as defined by the ______. Level II contains
the jugulodigastric node at the level of the jugular vein as it crosses the ________ and is a common lymphatic pathway for the
majority of the upper aerodigestive tract.

Answer 19

posterior border of the jugular vein
posterior belly of the digastric muscle

Question 20

Neck Node Level V contains the posterior triangle of the neck, boarded by _______, and is at particular risk for nasopharyngeal primaries.

Answer 20

the trapezius posteriorly, the SCM anteriorly, and the
clavicle inferiorly

Question 21

Level
VI are the prelaryngeal lymph nodes (____), which extend from the
inferior edge of the thyroid cartilage to the sternal notch, bounded laterally by
the sternal heads of the SCM.

Answer 21

delphian nodes

Question 22

. Just superior to level II, following the carotid
sheath to the skull base are the junctional or retrostyloid nodes, which may be at
risk when there is ipsilateral nodal disease. Medial to these nodes and to level II
lie the retropharygeal nodes ______, which lie in the regions
anterior to the prevertebral fascia, which in turn surrounds the longus capitis and
the longus colli muscles

Answer 22

or nodes of Rouviere

Question 23

The oral cavity encompasses three major subsites:

Answer 23

the oral tongue, the floor of
mouth, and the buccal mucosa.

Question 24

The nasopharynx is bounded superiorly and posteriorly by

Answer 24

the sphenoid sinus,
clivus, and the prevertebral fascia of C1 and C2

Question 25

The oropharynx anteriorly is bounded by the_____, laterally by the ____, superiorly by ______, and posteriorly by ________.

Answer 25

base of tongue tonsils the soft palate the posterior pharynx

Question 26

The pharyngeal constrictor muscles (PCM) lie along the posterior aspect of the naso- and oropharynx, bounded by the parapharyngeal space. The PCM may be further divided into (1) the superior PCM starting at _____; (2) the middle PCM, ______; and (3) the inferior PCM, which continues from the

Answer 26

the occipital condyle to the hyoid starting 0.5 cm superior to the hyoid and ending at the inferior edge of the hyoid inferior aspect of the hyoid to the esophagus

Question 27

The larynx is subdivided into three anatomic regions:

Answer 27

the supraglottis (containing the epiglottis, the arytenoid and aryepiglottic folds, and the ventricular bands or false cords), the glottis (a 1-cm plane extending inferiorly from the lateral margin of the ventricle, including the true vocal cords and commissures), and the subglottis (from the inferior border of the glottis to the inferior aspect of the cricoid).

Question 28

Both anatomical and clinical studies have shown that bronchogenic tumors frequently spread directly into mediastinal lymph nodes, bypassing intrapulmonary and hilar lymph nodes. This phenomenon appears to occur more frequently for________

Answer 28

upper lobe tumors.

Question 29

For right-sided bronchogenic tumors, these pathways most frequently lead to ipsilateral paratracheal and subcarinal lymph node stations. For left-sided tumors, particularly those arising in the left upper lobe, direct spread to______predominates. Second, right lung segments drain predominantly into ________ Conversely, left lung tumors commonly spread to _____,75–77 especially left lower lobe tumors. Third, direct passageways to the supraclavicular fossa exist but are rare

Answer 29

para-aortic and aortopulmonary (AP) window stations the ipsilateral mediastinum. both sides of the mediastinum

Question 30

The inferior aspect of the costodiaphragmatic recess often extends to the level of the _______. The posteromedial extent of the pleura often wraps anteriorly over the _________.

Answer 30

midkidney descending aorta

Question 31

The cervical esophagus extends from the cricopharyngeus muscle (___ from the incisors) to the level of the thoracic inlet (___ from the incisors). The thoracic esophagus extends from the thoracic inlet to the diaphragm and is sometimes divided into upper, middle, and lower sections. The carina is located at approximately ____ from the incisors and the gastroesophageal junction is located at approximately ____

Answer 31

~15 cm ~18 cm 25 cm 40 cm.

Question 32

In the female, the breast originates from a roughly circular base or bed extending from

Answer 32

the lateral border of the sternum to the midaxillary line from medial to lateral and from the second through sixth ribs superior to inferior

Question 33

Screening mammography includes two standard views of each breast: ______. These images are taken at approximately ____ angulation to each other (i.e., they are not orthogonal).

Answer 33

a craniocaudal (CC) view and a mediolateral oblique (MLO) view 45-degree

Question 34

The stomach is a distensible organ located in the left upper abdomen. It is classically divided into four parts:

Answer 34

the gastroesophageal junction (cardia), fundus, body, and pylorus (antrum).

Question 35

For tumors within the stomach, the perigastric region located along the greater and lesser curvatures of the stomach are typically the initial draining lymph node basin. The other primary lymph node regions are those along the three arterial branches of the celiac axis

Answer 35

(common hepatic, left gastric, splenic).

Question 36

Hepatocytes within the liver secrete bile (an important agent for digestion) into bile canaliculi, the initial branches of the intrahepatic duct system. These canaliculi drain bile into larger and larger channels that eventually become the _____, draining bile from the left and right lobes of the liver, respectively. These exit the liver from the porta hepatis and join to form the ________. The cystic duct joins the common hepatic duct to form the______. The common bile duct extends to, and empties into, the duodenum.

Answer 36

left and right hepatic ducts common hepatic duct (~4 cm in length) common bile duct (~10 cm in length)

Question 37

________ are perihilar tumors that involve the bifurcation of the common hepatic duct.

Answer 37

Klatskin tumors

Question 38

The testicles have an interesting lymphatic drainage that differs with laterality, essentially mirroring the differences in venous drainage of the two testicles. On the right, the testicle drains into ________________ following the right testicular vein. On the left, the testicle drains to the __________ following the left testicular vein.

Answer 38

the para-aortic nodes along the lower portion of the inferior vena cava at about the level of L3-L4 renal hilar nodes

Question 39

The rectum is the final, straight portion of the large bowel, measuring approximately______in length, beginning at the transition from the sigmoid colon with the fusion of the tenia into the circumferential longitudinal muscle

Answer 39

12 cm

Question 40

Posteriorly, the entire rectum is ______, whereas anteriorly, the peritoneal reflection occurs at approximately _________ in males at the posterior aspect of the bladder (superior to the prostate) and _________ in females, forming the rectouterine pouch (or pouch of ____). Below this point, the ________of the rectum is entirely extraperitoneal.

Answer 40

extraperitoneal 7 to 9 cm from the anal verge 5 to 8 cm from the verge Douglas distal third

Question 41

The trigone is the _______portion of the bladder, defined by the two ureteral orifices posteriorly and the urethral orifice inferiorly

Answer 41

posterior and inferior

Question 42

Anterior to the bladder, this loose connective tissue is termed the space of ________or retropubic space.

Answer 42

Retzius

Question 43

The uterus lies between the bladder anteriorly and the rectum posteriorly, covered by a layer of peritoneum. Laterally lie the fallopian tubes and ovaries, which are anchored medially by the _______ and laterally by the _________

Answer 43

ovarian ligament (or utero-ovarian ligament) suspensory ligament of the ovary (or infundibulopelvic [IP] ligament).

Question 44

The ovarian arteries originate from the abdominal aorta, just inferior to the renal vessels, following a course anterior to the psoas on the left and crossing anterior to the inferior vena cava to the psoas on the right, both sides crossing ______ to the ureter and then crossing ________ with the IP ligament to the ovaries.

Answer 44

anterior medially

Question 45

Lateral to the uterine cervix and corpus is the parametrium that caudally consists of the paracervical tissue, including ____________

Answer 45

the cardinal ligament, uterine artery and vein, and the ureter as it courses anteriorly to the bladder.

Question 46

the parametrium continues as the broad ligament, terminating at the _________. Posteriorly the cervix is anchored to the sacrum via the uterosacral ligament, which classically attaches at the _____ foramen

Answer 46

suspensory ligament of the ovary third sacral

Question 47

Within the prostate five distinct zones exist:

Answer 47

the peripheral zone, the central zone, the transitional zone, the periurethral glandular tissue, and the anterior fibromuscular stroma

Question 48

The peripheral zone accounts for the majority of the gland (70% of glandular tissue) as well as the majority of cancers (60% to 70%). The peripheral zone is located posteriorly and laterally within the gland. This zone is hyperintense on T2 MRI and care should be taken to include it when treatment planning with MRI. The central zone accounts for an additional 25% of glandular tissue and lies near the origin of the seminal vesicles, accounting for 10% of cancers. The transitional zone surrounds the urethra cephalad to the insertion of the ejaculatory duct, may hypertrophy with age, and is the origin of 10% to 20% of cancer within the prostate.

Question 49

The _______is a series of valveless veins anterior to the vertebral bodies that received drainage from the deep pelvic veins and prostate gland.

Answer 49

Batson venous plexus

Question 50

If CT alone is used for definition of the prostate for treatment planning, the penile bulb may provide a useful reference point for ascertaining the apex of the gland, which lies approximately ___ superior to the bulb, although there is significant interpatient variation.

Answer 50

15 to 18 mm

Question 51

The lymphatic system is a loosely organized system but generally follows somewhat predictable paths. Small lymphatic vessels form within the tissues of the body, drain into one or more lymph nodes, and eventually drain into larger lymph trunks. These unite to form either the _______, which empties into the venous system at the subclavian vein–internal jugular vein junction.

Answer 51

thoracic duct or right lymphatic duct

Question 52

Contents of cavernous sinus

Answer 52

CN III, IV, VI, V1 V2 and ICA