Case Challenge

Brain

Vascular

Daniel Cornfeld

Gain confidence interpreting Subtle Strokes Cases on CT and MRI with MRI Online. Quiz yourself using real-world, interactive scrollable cases &amp; earn CME. Try it free!

Case Review

Neuroradiology

Vascular Imaging

Case 1 - 60-year-old with double vision and dizziness.

Case 2 - 65-year-old with altered mental status.

Case 3 - 65-year-old. Altered mental status.

Case 4 - 68-year-old. Dysphagia and aphasia.

Case 5 - 82-year-old with right hemiparesis.

Case 6 - 70-year-old with confusion.

Case 7 - 60-year-old with right sided weakness.

Case 8 - 70-year-old with right-sided weakness.

Case 9 - 68-year old with aphasia.

Case 10 - 50-year-old with right-sided weakness.

Case 11 - 65-year-old with right visual field defects.

Case 12 - 65-year-old with right-sided weakness.

Case 13 - 60-year-old with left-sided weakness.

Case 14 - 60-year-old with left-sided stroke symptoms.

Case 15 - 60-year-old with bilateral weakness.

Case 16 - 50-year-old with right-sided weakness.

Case 17 - 65-year-old with right-sided weakness.

Case 18 - 60-year-old with altered mental status.

Case 19 - 55-year-old with aphasia.

Case 20 - 60-year-old with left-sided weakness.

Case 21 - 60-year-old with left hemiparesis.

Case 22 - 60-year-old with left visual field defects.

Case 23 - 68-year-old with weakness.

Case 24 - 60-year-old with bilateral weakness.

Case 25 - 90-year-old with acute left hemiplegia.

Subtle Stroke Case Challenge

Course Evaluation

Post-Course Activities

Learn to master subtle stroke cases on CT and MRI! Gain experience detecting strokes on CT by reviewing the 25 cases of subtle strokes presented in this module. The purpose is not to comprehensively explain the role of imaging in the evaluation of acute stroke or to teach a junior physician how to approach a CT scan of the brain. Instead, by reviewing these difficult cases, the reader will become better at detecting the subtle CT findings of acute stroke. Some of these cases were initially interpreted correctly. Many were not.

Subtle Strokes Case Challenge

Case Findings (Scan 1)
Hemorrhage: None
Hydrocephalus: None
Herniation: None
Gray-white differentiation/wedge-shaped hypodensity/cortical involvement: Yes.
Complete loss of gray-white matter differentiation in the posterior left frontal operculum and insular regions.
Deep gray nuclei: Hypoattenuation of the left caudate head, caudate body, putamen, and globus pallidus (FLAIR anatomy review).
Hyperdense vessels: Hyperdense left middle cerebral artery M1 segment.

Case Discussion:
1. Axial images demonstrate loss of gray-white matter differentiation in the left frontal parenchyma and left striatum (caudate, putamen, globus pallidus). These should be evident with a slice by slice approach on 'stroke' window, even when the study may be technically less than ideal to interpret. These findings suggest an acute infarct.
2. The next finding to notice, usually on 'brain' window, is for any hyperdense vessels. In this case, the left middle cerebral artery M1 segment and the supraclinoid internal carotid artery appear slightly dense, suggestive of thrombus formation.

Imaging follow up MRI 24 hours later (Scan 2)
Subsequent review of the ADC map demonstrates diffusion restriction in the left frontal opercular and striatocapsular regions, supplied by the middle cerebral artery M2 superior division and lateral lenticulostriate arteries respectively.
Interestingly, the FLAIR sequence does not demonstrate as much signal changes compared to the head CT and ADC map. This is most suggestive of a hyperacute infarct, generally within 0-6 hours of symptom onset. Since the abnormality is also evident on CT, the age of the stroke is likely in the latter part of the 0-6 hour window. If there is diffusion restriction and corresponding FLAIR signal abnormality, the infarct is generally greater than 6 hours in age. Also note the loss of flow voids in the left cervical internal carotid artery, supraclinoid internal carotid artery, and left middle cerebral artery M1, M2, M3, and M4 segments; this could reflect occlusion and/or slow vascular flow.
Note that it is unusual to view ADC maps without first looking at the diffusion images. This was an old case and we could not find the diffusion images for inclusion.


Non-Contrast CT