Skull and Blood Supply to the Brain

Question 1

for radiology of the head, ____ is most commonly available; it is most commonly requested for screening in trauma (for fractures, radiopaque intracranial foreign bodies)

Answer 1

x-ray

Question 2

materials s/a stone, cement, metal w/c are very dense

Answer 2

radiopaque materials

Question 3

invisible in x-ray; ex: wood, glass, plastics

Answer 3

radiolucent materials

Question 4

1. for examination of brain trauma, stroke, and intracranial pathologies
2. superior than MRI in detecting fractures, foreign bodies, and calcifications
3. cheaper than MRI

Answer 4

CT scan

Question 5

_____ for bones and _____ for soft tissue (new growth)

Answer 5

CT scan

MRI

Question 6

1. reserved for mass lesions
2. cannot detect intracranial calcifications
3. metallic foreign bodies and implants will affect imaging and cause artifacts

Answer 6

MRI

Question 7

involves direct injection of dye and mapping of blood vessels

Answer 7

angiography

Question 8

1. Pt lying on the table; x-ray coming from the front; casette is under the table
2. One of the most commonly requested projection of the skull (together w/ lateral view)

Answer 8

skull AP view (frontal projection)

Question 9

1. Side of interest/trauma should be indicated
2. Pathology should be closest to the film/indicator
3. Requested together w/ the skull AP

Answer 9

skull lateral view

Question 10

1. For occipital bone

2. Similar to AP view but X-ray is tangential

Answer 10

towne’s view (AP axial)

Question 11

1. For trauma or fractures to the zygomatic arch

2. Pt’s neck is hyperextended

Answer 11

submentovertex view (zygomatic arch)

Question 12

1. Technique for paranasal sinuses and facial bones

2. For examination of sinuses when suspecting sinusitis

Answer 12

water’s view

Question 13

for paranasal sinuses, include the ____ through opened mouth

Answer 13

sphenoid sinus

Question 14

1. For injuries to the frontal bone

2. Frontal bone is in direct contact w/ the film

Answer 14

caldwell’s view (frontal bone)

Question 15

1. An interventional procedure for the dx and/or tx of intracranial pathology
2. Uses a catheter, x-ray imaging guidance and an injection of contrast material to examine blood vessels in the brain for abnormalities s/a aneurysms & disease s/a atherosclerosis (plaque)

Answer 15

cerebral angiography

Question 16

gold standard in evaluation of cerebral arteries

Answer 16

cerebral angiography

Question 17

cerebral angiography indications

Answer 17

1. Evaluate arteries of the head and neck before surgery
2. Provide additional information on abnormalities seen on MRI or CT of the head, such as the blood supply to a tumor
3. Prepare for other medical tx, s/a in the surgical removal of a tumor
4. Preparation for minimally invasive tx of a vessel abnormality

Question 18

CEREBRAL ANGIOGRAPHY

1. Involves insertion of long catheter from ____ to the ____
2. Intracranial angiography demonstrates the cerebral blood vessels by injection of radiopaque material into the circulation of the carotid and vertebral arteries
3. When the roentgenographic exposure is made during or immediately after the injection of contrast medium, an ___ is obtained
4. A ___ is obtained when the roentgen film is exposed 3 or 4 sec later
5. Under normal conditions, only blood vessels of the injected side are visible
6. Vertebral angiography is technically difficult and not often indicated

Answer 18

1. femoral artery; carotid artery
2. arteriogram
3. venogram

Question 19

CEREBRAL ANGIOGRAPHY INDICATIONS

1. Dx and tx of ___
2. Investigation of ___
3. Confirming brain death

Answer 19

1. aneurysms, acute ischemic stroke, vascular abnormalities, cerebral vangiospasms post subarachnoid hemorrhage, meningioma (preoperative embolization)
2. reversible cerebral vasoconstriction syndrome; moya-moya syndrome

Question 20

1. Noninvasive technique that allows visualization of the internal and external carotid arteries and vertebral arteries
2. Can include just the intracranial compartment or also extend down to the arch of the aorta
3. Overaching goal of this examination is an optimal enhancement of the carotid arteries w/ little to no venous component

Answer 20

CT angiography of the cerebral arteries (CTA carotids)

Question 21

CT angiography of the cerebral arteries (CTA carotids) indications

Answer 21

1. Ischemic stroke to detect occlusion and thrombosis
2. Transient ischemic attack to detect carotid artery stenosis
3. Subarachnoid hemorrhage for detection of aneurysms
4. Cerebral parenchymal hemorrhage to assess for the presence of a vascula malformation or ongoing bleeding (spot sign)

Question 22

CT angiography of the cerebral arteries (CTA carotids) contraindications

Answer 22

1. Previous severe rxn to iodinate

2. Non-compliance

Question 23

CT angiography of the cerebral arteries (CTA carotids) advantages

Answer 23

1. Ability not only to evaluate the vessels from their origin (aortic arch to intracranial portion), but also assess non-vascular neck structures and brain parenchyma
2. Less expensive and at a low risk

Question 24

CT angiography of the cerebral arteries (CTA carotids) disadvantages

Answer 24

1. Inability to select a single vessel and the fact that it images the vessel at only one time does limit the ability to evaluate flow-related features of complex malformations
2. Has lower resolution than catheter angiography, making the assessment of subtle wall changes s/a those seen in dissection or vasculitis, making it difficult to identify
3. Compared to MR angiography, its main disadvantage is the need for both ionizing radiation and IV contrast

Question 25

alternative to conventional angiography and CT angiography, eliminating the need for ionizing radiation and iodinated contrast media, and sometimes contrast media altogether

Answer 25

magnetic resonance angiography (MRA)

Question 26

magnetic resonance angiography (MRA) advantages and applications

Answer 26

1. contrast-enhanced MR angiography

2. non-contradt enhanced MR angiography

Question 27

technique involving 3D spoiled gradient-echo (GE) sequences, w/ administration of gadolinium-based contrast agents (GBCA); it can be used to assess vascular structures of almost any part of the body

Answer 27

contrast-enhanced MRA

Question 28

1. performed in several ways including:
   a. time of flight angiography
   b. phase contrast angiography
   c. 3D electrocardiograph-triggered half-Fourier spin echo
2. these techniques are time consuming

Answer 28

non-contrast enhanced MRA

Question 29

1. Vascular supply of the brain
2. Named after the English physician Thomas Willis who first described the anatomy of the circle in 1664 in his book “Cerebri anatome: cui accessit nervorum descriptio et usus” (The Anatomy of Brain and Nerves). He called his discovery “circulus arteriosus cerebri”
3. He was also responsible for the numbering of the cranial nerves
4. He died in 1675 from pleurisy and hus remains are buried at Westminster Abbey in London, UK

Answer 29

circle of willis

Question 30

1. Arterial polygon (heptagon) formed as the internal carotid and vertebral systems anastomose around the optic chiasm & infundibulum of the pituitary stalk in the suprasellar cistern
2. This communicating pathway allows equalization of blood flow between the 2 sides of the brain, and permits anastomotic circulation, should a part of the circulation be occluded

Answer 30

circle of willis

Question 31

vessels comprising the circle of willis: anterior circulation

Answer 31

1. left and right internal carotid arteries (ICA)
2. horizontal (A1) segments of the left and right anterior cerebral arteries
3. single anterior communicating artery

Question 32

vessels comprising the circle of willis: posterior circulation

Answer 32

1. leftt and right posterior communicating arteries (PCOM)
2. horizontal (P1) segments of the left and right posterior cerebral arteries
3. single basilar artery

Question 33

1. Terminal branch of the common carotid artery
2. It arises most frequently between C3 and C5 vertebral level, where the common carotid bifurcates
3. Enters the skull base through the carotid canal

Answer 33

internal carotid artery

Question 34

1. Paired arteries, each arising from the respective subclavian artery
2. Ascending in the neck to supply the posterior fossa and occipital lobes
3. Provide segmental vertebral and spinal column blood supply

Answer 34

vertebral arteries

Question 35

1. Along with the middle cerebral artery, forms the termination of the internal carotid artery
2. Smaller of the two, and arches anteromedially to pass anterior to the genu of the corpus callosum, dividing as it does so into its major branches: ____
3. Supplies the medial aspect of the cerebral hemispheres back to the parietal lobe

Answer 35

anterior cerebral artery

2. pericallosal and callosomarginal arteries

Question 36

1. Arises from the anterior cerebral artery and acts as an anastomosis between the left and right anterior cerebral circulation
2. Approx. 4mm in length
3. Demarcates the junction between the A1 and A2 segments of the anterior cerebral artery

Answer 36

anterior communicating artery

Question 37

1. Makes up the posterior linkage in the circle of Willis
2. Originates from the posterior aspect of the C7 (communicating) segment of the internal carotid artery and extends posteromedially to anastomose w/ the ipsilateral posterior cerebral artery and form part of the circle of willis

Answer 37

posterior communicating artery

Question 38

1. Are the terminal branches of the basilar artery and supply the occipital lobes and posteromedial temporal lobes
2. SUPPLY: Occipital lobes and posteromedial temporal lobes

Answer 38

posterior cerebral artery