Radiopaque microspheres–standard CT findings.

<p><b>A</b> RMS.a. Non-enhanced CT 2 hours after embolization. Marked linear hyperdensity (blue asterisk) corresponding to an occluded subsegmental artery (arterial enhancement). The type of arterial enhancement was comparable to iodized oil. <b>B</b> RMS.sa. Non-enhanced CT 2 hours after embolization. Linear (blue asterisk) and patchy hyperdensities (red asterisk) corresponding to occluded subsegmental and interlobular arteries and sinusoids (arterial and parenchymal enhancement). Note the more intense arterial and parenchymal enhancement compared to A. The type of arterial and parenchymal enhancement was comparable with iodized oil. <b>C</b> RMS-HEP.sa. Non-enhanced CT 2 hours after embolization. Note the more intense arterial (blue asterisk) and parenchymal enhancement (red asterisk) than A and B. <b>D</b> RMS-HEP.sa. Non-enhanced CT 7 days after embolization. Note the weaker arterial (blue asterisk) and parenchymal (red asterisk) enhancement compared to C. Note the hypodense areas in the embolized liver parenchyma (blue arrowhead) representing tissue necrosis.</p

Histopathological findings.

<p>Histopathological findings.</p

Standard microspheres–standard CT findings.

<p>SMS.a. Non-enhanced CT 2 hours after embolization. In contrast to the other study groups, there was neither arterial nor parenchymal enhancement.</p

Iodized oil–standard CT findings.

<p><b>A</b> IO.a. Non-enhanced CT 2 hours after embolization with 0.5 mL iodized oil. Linear hyperdensities (blue asterisk) corresponding to an occluded subsegmental artery (arterial enhancement) and patchy hyperdensities (red asterisk) corresponding to occluded interlobular arteries and sinusoids (parenchymal enhancement). <b>B</b> IO.sa. Non-enhanced CT 2 hours after embolization. Note the lower arterial (blue asterisk) and parenchymal (red asterisk) enhancement compared to A. <b>C</b> IO.sa. Non-enhanced CT 7 days after embolization. Note the less intense arterial (blue asterisk) and parenchymal (red asterisk) enhancement compared to B.</p

Standard CT findings.

<p>Standard CT findings.</p

Study groups.

<p>Study groups.</p

Radiopaque microspheres–histopathological findings.

<p><b>A</b> RMS.a. HE staining. Incipient sinusoidal penetration of microspheres (white arrowhead). <b>B</b> RMS.sa. HE staining. Multiple microspheres within a subsegmental artery (white arrowheads). There were only mild inflammatory changes compared to iodized oil, but signs of cell death were present. <b>C</b> RMS.sa. HE staining. Focal areas of parenchymal necrosis, represented by anucleate hepatocytes (white arrowhead). The black asterisk indicates the central vein. <b>D</b> RMS-HEP.sa. HE staining. Seven days after embolization, there were large areas of severe confluent parenchymal necrosis (black arrowhead), accompanied by a hemorrhagic rim (white arrowheads) with necrosis of the periportal fields. Note the microspheres within the subsegmental (black asterisk) and interlobular arteries (white asterisk).</p

Standard microspheres–histopathological findings.

<p>SMS.a. HE staining. Microspheres in the interlobular arteries (black asterisk). Note the blood retention within the sinusoids (white arrowheads), which is a potential sign of embolization-related reactive hyperemia. There were no qualitative differences regarding the histopathological findings between the standard and the radiopaque microspheres for the acute setting.</p