Contrast-Enhanced Ultrasound-Guided Biopsy of Focal Liver Lesions not Visualized Well on Standard B-Mode Ultrasound - Partovi, Sasan; Lu, Ziang; Kessner, Rivka; Yu, Alice; Ahmed, Yasmine; Patel, Indravadan J.; Nakamoto, Dean; Azar, Nami (Digestive Disease Interventions, 2017)