Table 3.

Comparison between Fluoroscopically Visible and Invisible Group

Note.- ^*When retained iodized oil in tumors was visible on both anteroposterior and lateral projection images, and thus was suitable for targeting tumor under guidance of biplane fluoroscopy, they were classified in fluoroscopically visible group. If index tumors were invisible or poorly visible on anteroposterior, lateral or both images, and thus not feasible for targeting tumor, they were regarded as part of fluoroscopically invisible group, ^†Subphrenic location of tumor was defined when index tumor was either located within 1 cm from diaphragm or abutting diaphragm, ^‡Visible group on US was defined when index tumor was conspicuous enough to allow percutaneous US-guided RFA, whereas invisible group was defined when index tumor was inconspicuous, thus unsuitable for percutaneous US-guided RFA. US = ultrasonography, RFA = radiofrequency ablation