The use of CEUS has expanded the field of interventional ultrasound and established new possibilities in patient management and diagnostic capabilities.
CEUS is a powerful diagnostic tool due to excellent time resolution and the possibility to keep a suspected lesion in the scanning plane throughout the entire contrast study. This feature frequently results in CT negative metastases being diagnosed with CEUS.
CEUS increase procedure success in biopsy of conventional B-mode ìinvisibleî lesions or large tumors with necrosis. CEUS performed before and immediately after ablation procedures greatly improve the success rate. CEUS can be of great value utilized intracavitary during abscess drainage or biliary and urological interventions.
Fusion ultrasound is an image application, whereby US images are presented simultaneously with corresponding, previously acquired images obtained from other imaging modalities such as CT, PET or MRI.
CEUS and fusion, and especially the combination of the two, has become decisive factors in liver imaging. These technologies increase detection sensitivity, enable immediate diagnosis of malignant versus benign lesion, plus facilitate differentiation between benign lesions such as hemangiomas, adenomas and FNH.
The basic advantage of image fusion with ultrasound is the possibility to combine the dynamic features of ultrasound with the virtues of CT and MR imaging. In addition, fusion used in combination with CEUS has a great potential for increasing procedure technique during guiding of interventional procedures
US-guided ablation of non-operable malignant liver lesions with RF or MW has become a well-established treatment that can be performed either percutaneously, laparoscopically, intraoperatively, during laparotomy or in combination with liver surgery. Ultrasound remains the most used guiding modality for these procedures for obvious reasons.
Dedicated devices for US-guidance of these procedures are rapidly evolving and CEUS and fusion performed before and after the ablation procedure improves the treatment results.
In case of non-operability, however, biopsy of lesions seen at CT, PET or MRI remains mandatory to confirm malignancy before chemotherapy or image-guided ablation with RF, MW, cryo or similar techniques. Use of CEUS and fusion may enable biopsy of otherwise ultrasound invisible lesions.
Use of CEUS and fusion may change the classic indications for biopsies and reduce the number of diagnostic biopsies. US-guided biopsies, however, will still be required in case of equivocal findings and likely will continue to serve as Gold-Standard. In addition, CEUS may visualize bleeding related to interventional US thus reducing the risk of severe complication.
Interventional US has countless applications and recent technological achievements described herein have provided new valuable elements to its use.