Table 4. Characteristics of 19 Lesions with Discordant APHE* between Ordinary Arterial-Phase Images and Arterial Subtraction Images.
| Characteristics | Total (n = 19) | |
|---|---|---|
| Signal intensity on precontrast T1-weighted images | ||
| Iso- or hypointensity | 8 (42.1) | |
| Hyperintensity | 11 (57.9) | |
| Pretreatment LI-RADS category | ||
| LI-RADS 4 | 4 (21.1) | |
| LI-RADS 5 | 14 (73.6) | |
| LI-RADS TIV | 1 (5.3) | |
| Pathological viability | ||
| Viable | 18 (94.7) | |
| Nonviable | 1 (5.3) | |
| Grade of viable HCC | ||
| Edmondson-Steiner grade 2 | 11 (63.1) | |
| Edmondson-Steiner grade 3 | 6 (31.6) | |
| Edmondson-Steiner grade 4 | 1 (5.3) | |
| Mean size, mm (range) | 14.5 (5–49) | |
| < 10 | 5 (26.3) | |
| 10–20 | 10 (52.5) | |
| > 20 | 4 (21.2) | |
| Change of LR-TR category† | ||
| LR-TR nonviable to viable | 9 (47.4) | |
| LR-TR equivocal to viable | 2 (10.5) | |
| Not changed | 8 (42.1) | |
Data are number (%) of lesions unless specified otherwise.
*Lesions not seen as APHE on ordinary arterial phase images but seen as APHE on arterial subtraction images, †Change in LR-TR category when arterial subtraction images were used. APHE = arterial phase hyperenhancement, HCC = hepatocellular carcinoma, LI-RADS = Liver Imaging Reporting and Data System, LR-TR = LI-RADS treatment response, TIV = tumor-in-vein