| Question 1: Which of the following is CT perfusion primarily measuring over time to be used in further quantitative analysis? |
| Reference: | Bushberg et al., The Essential Physics of Medical Imaging, 3rd ed., Lippincott, Williams, and Wilkins, 2012, p. 346. |
| Choice A: | Blood vessel volume |
| Choice B: | Enhancement due to iodine contrast |
| Choice C: | Dissolved oxygen |
| Choice D: | The blood oxygen level-dependent signal |
| Question 2: About how many sets of images of the same anatomic area are acquired for a typical head CT perfusion study? |
| Reference: | Bushberg et al., The Essential Physics of Medical Imaging, 3rd ed., Lippincott, Williams, and Wilkins, 2012, p. 346. |
| Choice A: | 5 |
| Choice B: | 10 |
| Choice C: | 20 |
| Choice D: | 40 or more |
| Question 3: Which of the following is NOT an analysis that can be made using CT brain perfusion imaging data? |
| Reference: | Bushberg et al., The Essential Physics of Medical Imaging, 3rd ed., Lippincott, Williams, and Wilkins, 2012, p. 346. |
| Choice A: | Blood volume |
| Choice B: | Neural oscillations |
| Choice C: | Cerebral blood flow |
| Choice D: | Time to peak enhancement |
| Question 4: During what timeframe (from last known normal) should CT brain perfusion, diffusion-weighted MR, or MR perfusion be used to determine patient selection for mechanical thrombectomy? |
| Reference: | Powers, et. al., "2018 Guidelines for the Early Management of Patients with Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association," Stroke 49:e46-e110, 2018, p. e59. |
| Choice A: | 0-3 hours |
| Choice B: | 3-6 hours |
| Choice C: | 6-24 hours |
| Choice D: | > 24 hours |
| Question 5: Why is CT brain perfusion typically performed at 80 kVp (or 70 kVp when available)? |
| Reference: | Sotoudeh, Bag, Brooks, "Code-Stroke CT Perfusion; Challenges and Pitfalls," Academic Radiology, article in press, https://doi.org/10.1016/j.acra.2018.12.013, p. 2. |
| Choice A: | Lower kV reduces radiation dose. |
| Choice B: | Lower kV decreases scan time. |
| Choice C: | The average x-ray energy (keV) corresponds to the k-edge of iodine. |
| Choice D: | A and C |
| Question 6: Which of the following is an advantage of CT perfusion over diffusion-weighted MR and MR perfusion for acute ischemic stroke (AIS)? |
| Reference: | Sotoudeh, Bag, Brooks, "Code-Stroke CT Perfusion; Challenges and Pitfalls," Academic Radiology, article in press, https://doi.org/10.1016/j.acra.2018.12.013, p. 1.
Powers, et. al., "2018 Guidelines for the Early Management of Patients with Acute Ischemi |
| Choice A: | CT is more cost effective and faster to complete, even at most comprehensive stroke centers. |
| Choice B: | CT perfusion has better axial resolution. |
| Choice C: | Lacunar infarcts and watershed infarcts are better seen on CT perfusion. |
| Choice D: | CT is more sensitive than MR at detecting AIS. |
