FRCR FRCR Neuroradiology

Question 1

Which MRI sequence is most sensitive for detecting acute ischemic stroke within the first few hours of symptom onset?

Accepted Answer

Diffusion-weighted imaging (DWI)

Answer

DWI detects restricted diffusion due to cytotoxic edema within minutes of ischemic onset, making it the most sensitive early sequence.

Question 2

What is the classic CT finding of subarachnoid hemorrhage (SAH) on a non-contrast scan?

Accepted Answer

Hyperdense blood filling the basal cisterns

Answer

Fresh clotted blood is hyperdense (35–90 HU) due to protein in hemoglobin, appearing bright white in the basal cisterns on non-contrast CT.

Question 3

Which arteries are most commonly responsible for hypertensive hemorrhage in the basal ganglia?

Accepted Answer

Lenticulostriate arteries

Answer

The lenticulostriate arteries are small perforating end-arteries from the MCA that are highly susceptible to hypertensive damage and rupture.

Question 4

The 'empty delta sign' on contrast-enhanced CT is associated with which condition?

Accepted Answer

Superior sagittal sinus thrombosis

Answer

Enhancement of the dural walls around a non-enhancing thrombus in the superior sagittal sinus creates a triangular filling defect — the 'empty delta sign'.

Question 5

Which imaging feature best distinguishes a high-grade glioma from a solitary metastasis on MRI?

Accepted Answer

Tumor infiltration crossing the corpus callosum

Answer

High-grade gliomas can infiltrate along white matter tracts and cross the corpus callosum ('butterfly glioma'), a pattern not seen with metastases.

FRCR - Fellow of the Royal College of Radiologists Practice Test

FRCR - Fellow of the Royal College of Radiologists Practice Test

FRCR FRCR Neuroradiology