NEURORADIOLOGY 2025 2026 COMPLETE
STUDY GUIDE NEUROIMAGING CONCEPTS
PRACTICE QUESTIONS and EXAM
PREPARATION
Neuroradiology Board & Registry Study Guide (2025–
2026)
Neuroimaging Concepts & Core Pathology
1. Which MR imaging sequence is considered the most
sensitive and earliest marker for identifying an acute
ischemic stroke, showcasing signal alterations within
minutes of symptom onset?
A. T2-Weighted Hyperintense Imaging
B. Fluid-Attenuated Inversion Recovery (FLAIR)
C. Diffusion-Weighted Imaging (DWI)
D. T1-Weighted Post-Contrast Gadolinium Sequence
Correct Answer: C
Rationale: DWI detects the random microscopic motion of water
molecules (Brownian motion). Within minutes of ischemic onset,
the failure of the ATP-dependent sodium-potassium pump causes
a fluid shift into the intracellular space (cytotoxic edema). This
cellular swelling restricts water movement, which appears as
hyperintensity on DWI. FLAIR and standard T2 sequences take
hours to show changes.
2. When evaluating an acute stroke on MRI, a region that
is hyperintense on Diffusion-Weighted Imaging (DWI)
must be matched with which finding on the
, corresponding Apparent Diffusion Coefficient (ADC)
map to confirm true restricted diffusion?
A. High signal intensity (bright)
B. Low signal intensity (dark)
C. Isointense signal matching cerebrospinal fluid
D. Overlapping blooming artifact
Correct Answer: B
Rationale: True acute restricted diffusion must show
hyperintensity on DWI and corresponding hypointensity (dark
signal) on the ADC map. If a lesion is bright on DWI and bright on
ADC, it represents "T2 shine-through" rather than acute ischemia.
3. On a non-contrast head CT of an acute ischemic
stroke, what is the underlying pathophysiology behind
the loss of the "insular ribbon" sign?
A. Localized bleeding into the basal ganglia
B. Intravascular pooling of calcified thrombi
C. Cytotoxic edema causing a loss of gray-white matter
differentiation
D. Microscopic collapse of the lateral ventricles
Correct Answer: C
Rationale: The insular ribbon sign refers to the normal
distinction between the gray matter of the insular cortex and the
adjacent white matter capsule. Because gray matter has a higher
metabolic rate, it is highly sensitive to ischemia. Rapid water
accumulation (cytotoxic edema) reduces its density, causing it to
match white matter and fade on CT.
4. What is the classic appearance of a hyperacute
epidural hematoma on a non-contrast head CT?
A. Crescent-shaped (concave) collection that crosses cranial
suture lines
B. Lens-shaped (biconvex), high-density collection that
does not cross cranial suture lines
, C. Diffuse speckling across the subarachnoid cisterns
D. Punctuated hyperdensity confined entirely to the brainstem
parenchyma
Correct Answer: B
Rationale: Epidural hematomas occur when arterial blood (most
commonly from a torn middle meningeal artery) collects under
high pressure between the skull and the periosteal dura layer. The
tough dural attachments at cranial sutures restrict its expansion,
forcing it into a biconvex or lentiform shape.
5. Conversely, a subdural hematoma classically presents
on a head CT as a crescent-shaped collection because the
blood accumulates between which two anatomical
layers?
A. The cranium wall and the periosteal dura mater
B. The meningeal dura mater and the arachnoid mater
C. The arachnoid mater and the pia mater surface
D. The pia mater and the gray matter tissue border
Correct Answer: B
Rationale: Subdural hematomas typically result from the
shearing of bridging cortical veins as they cross into the superior
sagittal sinus. The blood accumulates in the potential space
between the dura and arachnoid maters. Because this space has
no suture boundaries, the blood spreads widely along the brain's
hemisphere, taking on a crescentic shape.
6. What CT imaging finding is the hallmark indicator of
an acute subarachnoid hemorrhage (SAH)?
A. A localized biconvex collection in the temporal lobe
B. Hyperdense fluid collection within the basal cisterns,
sulci, and fissures
C. Hypodense shifting of the midline midline structures
D. Symmetrical air pockets within the lateral ventricles
Correct Answer: B
, Rationale: Acute SAH involves bleeding into the subarachnoid
space, where cerebrospinal fluid circulates. On a non-contrast CT,
acute blood appears bright (hyperdense) as it fills the normally
dark, CSF-filled spaces like the Sylvian fissures, interhemispheric
fissure, and basal cisterns.
7. What vascular pathology is the most common cause of
a spontaneous, non-traumatic subarachnoid
hemorrhage?
A. Thrombosis of the internal jugular vein
B. Rupture of an intracranial saccular (berry) aneurysm
C. Dissection of the superficial temporal artery
D. Low-flow dural arteriovenous fistula
Correct Answer: B
Rationale: Roughly 85% of non-traumatic subarachnoid
hemorrhages are caused by the rupture of an intracranial saccular
aneurysm. These aneurysms typically develop at vascular branch
points within the Circle of Willis, particularly at the anterior
communicating artery origin.
8. Which of the following MR sequences leverages
magnetic susceptibility to identify microscopic blood
products, such as hemosiderin, or subtle calcifications
via "blooming" artifacts?
A. T1-Weighted Spin Echo
B. Proton Density Imaging
C. Susceptibility-Weighted Imaging (SWI) or Gradient
Recalled Echo (GRE)
D. Diffusion Tensor Imaging (DTI)
Correct Answer: C
Rationale: SWI and GRE sequences are highly sensitive to
distortions in the local magnetic field caused by paramagnetic
materials like deoxyhemoglobin, methemoglobin, and
hemosiderin. This sensitivity causes blood products to look larger
and darker ("blooming"), making it a useful sequence for
STUDY GUIDE NEUROIMAGING CONCEPTS
PRACTICE QUESTIONS and EXAM
PREPARATION
Neuroradiology Board & Registry Study Guide (2025–
2026)
Neuroimaging Concepts & Core Pathology
1. Which MR imaging sequence is considered the most
sensitive and earliest marker for identifying an acute
ischemic stroke, showcasing signal alterations within
minutes of symptom onset?
A. T2-Weighted Hyperintense Imaging
B. Fluid-Attenuated Inversion Recovery (FLAIR)
C. Diffusion-Weighted Imaging (DWI)
D. T1-Weighted Post-Contrast Gadolinium Sequence
Correct Answer: C
Rationale: DWI detects the random microscopic motion of water
molecules (Brownian motion). Within minutes of ischemic onset,
the failure of the ATP-dependent sodium-potassium pump causes
a fluid shift into the intracellular space (cytotoxic edema). This
cellular swelling restricts water movement, which appears as
hyperintensity on DWI. FLAIR and standard T2 sequences take
hours to show changes.
2. When evaluating an acute stroke on MRI, a region that
is hyperintense on Diffusion-Weighted Imaging (DWI)
must be matched with which finding on the
, corresponding Apparent Diffusion Coefficient (ADC)
map to confirm true restricted diffusion?
A. High signal intensity (bright)
B. Low signal intensity (dark)
C. Isointense signal matching cerebrospinal fluid
D. Overlapping blooming artifact
Correct Answer: B
Rationale: True acute restricted diffusion must show
hyperintensity on DWI and corresponding hypointensity (dark
signal) on the ADC map. If a lesion is bright on DWI and bright on
ADC, it represents "T2 shine-through" rather than acute ischemia.
3. On a non-contrast head CT of an acute ischemic
stroke, what is the underlying pathophysiology behind
the loss of the "insular ribbon" sign?
A. Localized bleeding into the basal ganglia
B. Intravascular pooling of calcified thrombi
C. Cytotoxic edema causing a loss of gray-white matter
differentiation
D. Microscopic collapse of the lateral ventricles
Correct Answer: C
Rationale: The insular ribbon sign refers to the normal
distinction between the gray matter of the insular cortex and the
adjacent white matter capsule. Because gray matter has a higher
metabolic rate, it is highly sensitive to ischemia. Rapid water
accumulation (cytotoxic edema) reduces its density, causing it to
match white matter and fade on CT.
4. What is the classic appearance of a hyperacute
epidural hematoma on a non-contrast head CT?
A. Crescent-shaped (concave) collection that crosses cranial
suture lines
B. Lens-shaped (biconvex), high-density collection that
does not cross cranial suture lines
, C. Diffuse speckling across the subarachnoid cisterns
D. Punctuated hyperdensity confined entirely to the brainstem
parenchyma
Correct Answer: B
Rationale: Epidural hematomas occur when arterial blood (most
commonly from a torn middle meningeal artery) collects under
high pressure between the skull and the periosteal dura layer. The
tough dural attachments at cranial sutures restrict its expansion,
forcing it into a biconvex or lentiform shape.
5. Conversely, a subdural hematoma classically presents
on a head CT as a crescent-shaped collection because the
blood accumulates between which two anatomical
layers?
A. The cranium wall and the periosteal dura mater
B. The meningeal dura mater and the arachnoid mater
C. The arachnoid mater and the pia mater surface
D. The pia mater and the gray matter tissue border
Correct Answer: B
Rationale: Subdural hematomas typically result from the
shearing of bridging cortical veins as they cross into the superior
sagittal sinus. The blood accumulates in the potential space
between the dura and arachnoid maters. Because this space has
no suture boundaries, the blood spreads widely along the brain's
hemisphere, taking on a crescentic shape.
6. What CT imaging finding is the hallmark indicator of
an acute subarachnoid hemorrhage (SAH)?
A. A localized biconvex collection in the temporal lobe
B. Hyperdense fluid collection within the basal cisterns,
sulci, and fissures
C. Hypodense shifting of the midline midline structures
D. Symmetrical air pockets within the lateral ventricles
Correct Answer: B
, Rationale: Acute SAH involves bleeding into the subarachnoid
space, where cerebrospinal fluid circulates. On a non-contrast CT,
acute blood appears bright (hyperdense) as it fills the normally
dark, CSF-filled spaces like the Sylvian fissures, interhemispheric
fissure, and basal cisterns.
7. What vascular pathology is the most common cause of
a spontaneous, non-traumatic subarachnoid
hemorrhage?
A. Thrombosis of the internal jugular vein
B. Rupture of an intracranial saccular (berry) aneurysm
C. Dissection of the superficial temporal artery
D. Low-flow dural arteriovenous fistula
Correct Answer: B
Rationale: Roughly 85% of non-traumatic subarachnoid
hemorrhages are caused by the rupture of an intracranial saccular
aneurysm. These aneurysms typically develop at vascular branch
points within the Circle of Willis, particularly at the anterior
communicating artery origin.
8. Which of the following MR sequences leverages
magnetic susceptibility to identify microscopic blood
products, such as hemosiderin, or subtle calcifications
via "blooming" artifacts?
A. T1-Weighted Spin Echo
B. Proton Density Imaging
C. Susceptibility-Weighted Imaging (SWI) or Gradient
Recalled Echo (GRE)
D. Diffusion Tensor Imaging (DTI)
Correct Answer: C
Rationale: SWI and GRE sequences are highly sensitive to
distortions in the local magnetic field caused by paramagnetic
materials like deoxyhemoglobin, methemoglobin, and
hemosiderin. This sensitivity causes blood products to look larger
and darker ("blooming"), making it a useful sequence for
