Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

5. HDS Neuro Psych > Neuroimaging > Flashcards

Neuroimaging Flashcards

1
Q

Neuroimaging Modalities

A
  • Plain radiographs
  • Ultrasound***
  • Computed Tomography (CT)
  • Magnetic Resonance Imaging (MRI)***
  • Nuclear Medicine (Scintigraphy)
  • Positron Emission Tomography (PET)
  • Myelography
  • Angiography

*** No ionizing radiation used

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Plain Radiographs

A
  • Advantages
    • Readily available in all hospitals
    • Easily obtained and relatively inexpensive
    • Portable
    • Provides details of the osseous structures
  • Disadvantages
    • Not good for brain parenchyma
    • Does not demonstrate the underlying brain
    • Uses ionizing radiation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Computed Tomography (CT)

Advantages vs Disadvantages

A
  • Advantages
    • Non-invasive
    • Readily available 24/7
    • Rapid scan time – < 5 seconds
    • Provides basic anatomic detail
    • Images can be reformatted into multiple planes
    • Allows for total body scanning
    • Not limited by ferrous materials
  • Disadvantages
    • Ionizing radiation
    • Not (usually) portable
      • Portable CT available in some institutions
    • Poor quality images
    • Posterior fossa images degraded by artifact from temporal bone
    • Iodinated intravenous contrast has limitations in those with allergies, asthma, renal failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Computed Tomography (CT)

Imaging Planes

A

3 planes ⇒ coronal, sagittal, and axial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Normal Brain Anatomy

A
  • Cerebrum
    • Frontal lobe
    • Parietal lobe
    • Occipital lobe
    • Temporal lobe
  • Cerebellum

Differentiate from white matter (darker on CT) vs. gray matter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Ventricular System

A
  • Two lateral ventricles
    • Each has a body and multiple horns:
      • Frontal (anterior)
      • Temporal (inferior)
      • Occipital (posterior)
    • Foramena of Monro
  • Third ventricle ⇒ Midline structure
    • Cerebral aqueduct of Sylvius
  • Fourth ventricle ⇒ Located in the midline posterior fossa
    • Foramena of Luschka** and **Magendie to basal cistern
      • Luschka ⇒ Lateral
      • Magendie ⇒ Medial
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Extracerebral Spaces

A
  • Epidural (extradural) space ⇒ potential space bound by sutures
    • Blood in epidural space cannot cross suture lines
  • Subdural space ⇒ potential space bound by interhemispheric fissure/tentorium
    • Blood in Subdural space cannot cross midline
  • Subarachnoid space/compartment ⇒ contains CSF and bridging veins
    • Blood cannot cross midline, contains veins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Vascular Structures

A
  • Arteries ⇒ Circle of Willis
    • Anterior circulation
      • Internal carotid arteries
      • Anterior cerebral arteries (and anterior communicating artery)
      • Middle cerebral arteries
      • Posterior communicating arteries
    • Posterior circulation
      • Vertebral arteries
      • Basilar artery
      • Posterior cerebral arteries
      • Anterior and posterior inferior cerebellar arteries (AICA/PICA)
      • Superior cerebellar arteries
  • Veins ⇒ Deep venous system
    • Cortical veins

Vascular structures can only be seen on CT if IV contrast is administered.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Indications for CT

A
  • Acute trauma
  • Altered mental status
  • Acute headache
  • Acute neurologic deficits (stroke)
  • Ventriculoperitoneal shunt malfunction
  • Orbital and mastoid infection
  • Chronic hearing loss
  • Chronic ⇒ Abnormal head shape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Computed Tomography (CT)

Indications for IV Contrast

A
  • Non-contrast CT Indications
    • Trauma
    • Stroke
    • Shunt studies
    • Temporal bone anatomy (hearing loss)
    • Bony/skull evaluation
  • Contrast CT Indications
    • Infection
    • Cerebral Abscess
    • Orbital cellulitis
    • Mastoiditis
    • Known tumor
      • Metastatic disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Pathology on CT

A
  • Definitive evaluation:
    • Intracranial hemorrhage
    • Skull/facial bone fracture
    • Craniosynostosis (early closure of suture)
    • Soft tissue infection (orbital cellulitis, mastoiditis)
    • Ventriculoperitoneal shunt malfunction
  • Screening evaluation:
    • Cerebrovascular Accident (CVA)
    • Masses
    • Intracranial infection
      • Acute
      • Chronic (TORCH)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hemorrhage

A

Blood is hyperdense (bright) compared to brain

  • Intraparenchymal ⇒ trauma, HTN, tumor, ruptured vascular malformation
  • Extraparenchymal
    • Subdural ⇒ trauma (shear injury), post-surgery
    • Epidural ⇒ trauma (direct)
    • Subarachnoid ⇒ ruptured aneurysm, trauma
    • Intraventricular ⇒ trauma, ruptured vascular malformation, premature newborns
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cerebrovascular Accident

A
  • Variety of etiologies: Thrombus, embolus, HTN/hemorrhage
  • Appearance on CT varies according to the timing of initial insult
    • Immediate: Hyperdense thrombus in affected vessel
    • Early (1-6 hours): Loss of gray-white differentiation, gyral swelling
    • Subacute (1st and 2nd week): Increasing, then decreasing swelling
    • Chronic: Volume loss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Magnetic Resonance Imaging (MRI)

Advantages vs Disadvantages

A
  • MRI Advantages
    • No ionizing radiation
    • Contrast enhancement with Gadolinium
      • Less likely to cause allergic reaction than iodinated contrast
    • Superb demonstration of brain anatomy and pathology
    • Can visualize vessels without contrast
    • Can do fetal MRI
  • MRI Disadvantages
    • High cost, limited availability
    • Not portable
    • Studies take up to 1-2 hours
    • Sedation may be required
    • Contraindicated in some patients
      • Pacemakers, cochlear implants, embedded metal
    • Gadolinium deposits in basal ganglia
      • So far, uncertain consequences
    • IV contrast cannot be given to patients with end stage renal disease
      • Gadolinium can cause nephrogenic systemic fibrosis, a potentially fatal scleroderma-like syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

MRI

Planes

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

MRI

Imaging Types

A

Variety of types of MRI (Ex. T1-weighted, T2-weighted, FLAIR) which can be performed to emphasize certain structures or abnormalities.

17
Q

Indications for Brain MRI

A
  • Neurologic deficits/acute stroke
  • Chronic headache
  • Infection
    • Complications of meningitis
  • Characterization of tumors
  • Seizure disorder
  • Demyelinating disease/multiple sclerosis
  • Congenital abnormalities/evaluation of abnormal prenatal ultrasound
18
Q

MRI

Indications for IV Contrast

A
  • Non-contrast
    • Trauma
    • Stroke
    • Headache
    • Seizure disorder
    • Congenital anomaly
  • Contrast
    • Infection
    • Tumor
    • Demyelinating disease/multiple sclerosis
19
Q

Indications for MR Angiography

A
  • Concern for aneurysm or other vascular malformation
    • Screening
      • Family history
      • Autosomal dominant polycystic kidney disease
    • Intracerebral hemorrhage concerning for vascular malformation
  • Concern for dural venous sinus thrombosis
    • Headache and hypercoagulability
    • Complicated infection (meningitis, mastoiditis)
20
Q

Ultrasound

Advantages vs Disadvantages

A
  • Advantages
    • Readily available
    • No ionizing radiation
    • Equipment is portable
  • Disadvantages
    • Operator dependent
    • Need open fontanelles for brain imaging ⇒ can only been performed in young infants!
21
Q

Ultrasound

Indications

A
  • Prenatal US
    • Useful for diagnosis of congenital structural abnormality
  • Postnatal cranial US
    • Follow-up of abnormal prenatal US
    • Best examination for germinal matrix/intraventricular hemorrhage (premature infants)
    • Birth trauma (hemorrhage, hypoxic-ischemic injury)
    • Large head circumference (hydrocephalus, benign enlargement of subarachnoid space)
22
Q

Angiography

(Arteriography)

A
  • Invasive procedure, performed under fluoroscopic guidance
    • Arterial puncture (most commonly femoral, but also brachial, axillary, etc.) is performed
    • Introduction of a guide wire over which a small-caliber vascular catheter is threaded
    • Catheter tip is guided into the artery of interest
    • Contrast medium injected through catheter tip to visualize arteries/veins in area of interest
  • Conventional angiography is used for demonstration of vascular abnormalities such as aneurysms and arteriovenous malformations (AVM)
    • “Gold standard” for demonstrating anatomy of small arteries and veins
  • For diagnosis, largely replaced by CT angiography (CTA) and MR angiography (MRA)
  • Widely used for intravascular therapy ⇒ lysis of thrombus, occlusion of aneurysms and AVMs
23
Q

Nuclear Medicine

Overview

A
  • Utilizes radioactive substance (radionuclides) in the dx and tx of disease
    • Radionuclides + other elements or pharmaceuticals → radiopharmaceuticals
    • Localize to specific organs or tissue receptors after IV admin
  • One use in neuro imaging is in brain death
    • Brain death ⇒ no uptake of tracer within brain parenchyma
    • Surrounding soft tissues remain perfused
24
Q

Positron Emission Tomography (PET)

A
  • Admin of radiopharmaceutical used to evaluate the metabolism of a particular organ or tissue
    • Specialized form of nuclear medicine
    • Info about physiology, anatomy and biochemical properties
  • PET is most commonly used in neurology, oncology and cardiology
    • For PET scans of the brain ⇒ fluorine-18 + glucose (fluorodeoxyglucose) (FDG) iused
  • Adjunctive study in evaluation of etiology of seizures and dementia

5. HDS Neuro Psych (46 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions