Article Figures & Data
Figures
- Fig 1.
A 33-year-old man with nasopharyngeal carcinoma and left ICA blowout. A, No right A1 segment is detected on the coronal MIP (5 mm) image (white arrow). B, Only a hair-thin PcomA is detected on the axial MIP (5 mm) image. C, The narrowest portion of the anterior and posterior collateral vessels is aplastic, and the patient is grouped as very high risk. The recruited collateral flows after PCO are indicated by gray arrows. D, Diffusion-weighted imaging shows left borderzone infarction and bilateral anterior cerebral artery thromboembolic infarction on the same day after left ICA embolization.
- Fig 2.
This 74-year-old man with nasopharyngeal carcinoma presented with massive hematemesis and epistaxis. A, Faint opacification of the AcomA (white arrow) is shown on the oblique MIP image (7 mm), which is hypoplastic. The target of embolization is the right ICA (black arrow) due to an ICA pseudoaneurysm (not shown). B, No right PcomA is detected on the axial MIP image (7 mm). C, This patient is interpreted as high risk because only 1 hypoplastic AcomA supplies the collateral flow (gray arrows). D, Right borderzone infarction and tiny left embolic infarctions developed 5 days after right ICA embolization (shown on diffusion-weighted imaging).
- Fig 3.
Images in a 36-year-old man with massive bleeding from a protruding tumor. A, Oblique MIP image (7 mm) shows that the AcomA (white arrow) diameter is >50% of the ipsilateral A2 artery (PCO side, hollow arrow). B, The left PcomA on the axial MIP image (5 mm) is aplastic. C, The patient is interpreted as low risk. The recruited collateral flows after PCO are indicated by gray arrows. D, Intraprocedural angiography shows irregular narrowing of the diseased left ICA (black arrow). No neurologic deficit was detected after left PCO.
- Fig 4.
A 52-year-old man with hypopharyngeal cancer and bleeding from the exposed left carotid artery. A, Axial MIP image (7 mm) shows a well-opacified AcomA (white arrow), which is >50% of the ipsilateral (PCO side) A2 segment (not shown). B, An axial MIP image (7 mm) reveals the left PcomA (black arrow), which is considered patent. C, The patient is considered very low risk. The recruited collateral flows after PCO are indicated by gray arrows. D, No cerebral infarction was found on brain CT 14 days after the left ICA embolization.
Tables
Assessment of the anterior and posterior collateral vessels and the collateral reserve
Collateral Reserve Anterior Collateral Vesselsa Patent Hypoplastic Aplastic Posterior collateral vesselsb Patent Very low risk Very low risk Low risk Hypoplastic Very low risk Intermediate risk High risk Aplastic Low risk High risk Very high risk
