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: No definite acute intracranial hemorrhage. Hyperdensity within the posterior left parietal encephalomalacia favored to reflect calcified components.
Hydrocephalus: Prominence of the ventricles and sulci, likely related to generalized parenchymal volume loss.
Herniation: No
Gray-white differentiation/wedge-shaped hypodensity/cortical involvement: Yes.
Region 1: Focal left parietal hypodensity, age-indeterminate though favored to reflect subacute/chronic infarcts given the degree of volume loss and gliosis.
Region 2: Focal left frontal hypodensity in the middle cerebral artery M2 superior division vascular territory, age-indeterminate, possible subacute/chronic in age.
Region 3: Small hypodensity in the right frontal corona radiata, age-indeterminate though potentially a acute/subacute infarct.
Deep gray nuclei: Preserved
Hyperdense vessels: None

Case Discussion:
Despite conscientious review of the head CT imaging, no definite acute transcortical infarct is seen, though age-indeterminate infarcts are present. A recommendation that MRI would be more sensitive for detection of acute ischemia would be reasonable to include given the clinical history.


Imaging follow up MRI (Scan 2)
Subsequent brain MRI demonstrates:
a) Acute/subacute superior left cerebellar acute/subacute left frontal infarcts (high DWI signal, abnormal FLAIR signal, ADC sequences not available to differentiate acute [low ADC] from subacute [isointense ADC]).
b) Acute/subacute left frontal infarct
c) Chronic left parietal infarct with cortical laminar necrosis.
d) Subacute/chronic right frontal corona radiata infarct.
Given the multifocal infarcts of varying ages, embolic etiology is favored.
2. Cerebellar and pontine infarcts often remain occult on unenhanced head CT examinations, usually related to beam hardening artifact from the dense temporal bone. MRI remains more sensitive for detecting acute brainstem and cerebellar infarcts.
A brief review of vascular territories, the posterior inferior cerebellar artery, anterior inferior cerebellar artery, and superior cerebellar artery supply the majority of the cerebellar parenchyma. With knowledge of the middle cerebellar peduncles, the vascular territories of the major arteries can be easily recalled:
a) The middle cerebellar peduncles are supplied by the anterior inferior cerebellar artery.
b) The superior cerebellar artery supplies cerebellar parenchyma superior to the middle cerebellar peduncles.
c) The posterior inferior cerebellar artery supplies the cerebral parenchyma inferior to the middle cerebellar peduncles.
d)When attempting to recall the vascular territory supply between the anterior inferior cerebellar artery and posterior inferior cerebellar artery, simply remember that the middle cerebellar peduncles are anterior to the cerebellar parenchyma. 


Primary teaching points:
1. Case example demonstrating limitations of unenhanced CT for detecting acute brainstem and cerebellar infarcts.
2. Review of the cerebellar vascular territories.


Non-Contrast CT

Which vessel is responsible for the cerebellar infarct?