Computed Tomography (CT Brain) Flashcards
7 cards from real Computed Tomography Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Computed Tomography (CT Brain) flashcards as text
On CT brain in a patient with suspected cerebral venous sinus thrombosis, the 'empty delta sign' is best seen:
Answer: On post-contrast CT as a filling defect within the superior sagittal sinus
The empty delta sign appears after contrast as a triangular filling defect (clot) surrounded by enhancing collateral vessels within the superior sagittal sinus.
Which artifact on CT brain appears as alternating bright and dark bands radiating from a high-density object such as a surgical clip?
Answer: Streak artifact
Streak artifacts radiate from high-density objects like metal clips or dense bone due to photon starvation and polychromatic X-ray beam effects.
A CT brain ordered for a 70-year-old with progressive cognitive decline shows diffuse enlargement of sulci and ventricles proportional to each other. This pattern most likely represents:
Answer: Cerebral atrophy (ex vacuo ventriculomegaly)
Proportional enlargement of both sulci and ventricles reflects volume loss (atrophy), distinguishing it from hydrocephalus where ventricles enlarge disproportionately.
The CT finding of 'cytotoxic edema' is characterized by:
Answer: Hypodensity that respects vascular territory boundaries and involves both gray and white matter
Cytotoxic edema from ischemia causes swelling of neurons and glia within a vascular territory, appearing as hypodensity involving both cortex and white matter.
On CT brain, the normal attenuation of CSF within the ventricles approximates:
Answer: 0–10 HU
CSF has nearly the same density as water and measures 0–10 HU on CT, appearing dark (hypodense) relative to brain parenchyma.
A non-contrast CT brain in a neonate with seizures reveals periventricular calcifications. The most likely causative infection is:
Answer: Cytomegalovirus (CMV)
Congenital CMV classically produces periventricular calcifications on CT, along with microcephaly and cortical malformations.
When performing a CT brain for evaluation of acute stroke, the primary reason to acquire a non-contrast series BEFORE contrast-enhanced sequences is:
Answer: To detect acute hemorrhage, which is a contraindication to thrombolytic therapy
Identifying acute hemorrhage on non-contrast CT is critical because thrombolytics (tPA) are absolutely contraindicated if hemorrhage is present.