Fusion Imaging–Guided Percutaneous Biopsy of Focal Hepatic Lesions With Poor Conspicuity on Conventional Sonography

Abstract

iver biopsy and radiofrequency ablation of focal hepatic lesions is widely performed under sonographic guidance, mainly because sonography is convenient, safe, and easily accessible, and it offers real-time guidance for interventional procedures. However, we quite frequently encounter focal hepatic lesions that have poor sonographic conspicuity; thus, it is difficult to accurately localize and target the index lesion. When the biopsy specimen is not adequate for pathologic examination, another biopsy is Hyun Jeong Park, MD, Min Woo Lee, MD, Mi Hee Lee, MD, Jiyoung Hwang, MD, Tae Wook Kang, MD, Sanghyeok Lim, MD, Hyunchul Rhim, MD, Hyo K. Lim, MD Received October 12, 2012, ORIGINAL RESEARCHObjectives-The purpose of this study was to evaluate the effectiveness of real-time fusion imaging (sonography combined with computed tomography or magnetic resonance imaging) for percutaneous sonographically guided biopsy of focal hepatic lesions with poor sonographic conspicuity.Methods-This study was conducted as a retrospective analysis of a prospective database and was approved by the Institutional Review Board. Patients who had target lesions with poor conspicuity on B-mode sonography for percutaneous biopsy were enrolled in the study. Lesion conspicuity was assessed by conventional B-mode sonography first and then by fusion imaging later in the same session. We compared lesion conspicuity and detection rates between B-mode sonography and fusion imaging and evaluated how many cases of initially invisible lesions on B-mode sonography became visible on fusion imaging. The technical success rate was evaluated on the basis of the final diagnoses, which were established by pathologic examination of the biopsy specimens as well as follow-up clinical and radiologic examinations.Results-A total of 22 patients were enrolled in the study. On fusion imaging, lesion conspicuity was increased in 63.6% of focal hepatic lesions (14 of 22). Moreover, 66.7% of lesions (6 of 9) that were invisible on B-mode sonography became visible on fusion imaging. The true-positive detection rate was significantly different between B-mode sonography and fusion imaging (9 of 22 versus 19 of 22; P = .0044). Percutaneous biopsy was performed for all lesions, including 3 target lesions that were invisible even on fusion imaging. The technical success rate was 95.5% (21 of 22).Conclusions-Fusion imaging is effective for percutaneous biopsy of focal hepatic lesions with poor sonographic conspicuity.

Application of imaging fusion combining contrast‐enhanced ultrasound and magnetic resonance imaging in detection of hepatic cellular carcinomas undetectable by conventional ultrasound

“…3 Previously, conventional ultrasound cannot provide precise guidance in 15-20% of lesions, including iso-echoic lesions in patients with advanced cirrhosis, lesions located near the diaphragm or deep areas within the liver, and post-RFA tumor residues. 4,5 Also the detection rate of hepatic lesions depends heavily on the operator's skill, if small HCC lesions can be precisely detected using conventional ultrasound, they can be ablated safely and easily. 6,7 Nowadays, contrast-enhanced ultrasound (CEUS) is widely used for detection and evaluation of the tumor blood flow perfusion of HCCs, with the advantages as noninvasive and it can be performed conveniently at the bedside.…”

Fusion imaging of real-time ultrasonography with CT or MRI for hepatic intervention

“…Many hepatic interventional procedures benefit from fusion imaging, enabling operators to conduct percutaneous interventional procedures for challenging target lesions that would otherwise not be possible [5,6,9,15-22]. For example, fusion imaging is useful for the percutaneous biopsy of a focal hepatic lesion that has poor conspicuity on B-mode US [6,23,24] (Figs.…”

“…For example, fusion imaging is useful for the percutaneous biopsy of a focal hepatic lesion that has poor conspicuity on B-mode US [6,23,24] (Figs. 2, 3).…”

“…In our daily practice, challenging small target lesions are more frequently detected than before due to recent advances in CT and MR technology. Therefore, fusion imaging has gained considerable attention since it can help operators conduct interventional procedures with high confidence and accuracy for challenging target lesions [5,6]. In this article, an electromagnetic (EM) tracking-based fusion imaging technique and its current clinical application for the hepatic intervention is reviewed.…”

Fusion imaging for intra-operative ultrasound-based navigation in neurosurgery

“…To target hepatic lesions, especially when characterized by poor sonographic signal [18], they perform an US-guided, minimal invasive (e.g., RF ablation) procedure merging the iUS imaging with CT or other modalities.…”