Modern Ultrasound Diagnostic Procedures in an Interdisciplinary Ultrasound Department: Challenge and Opportunities for Radiologists

Contrast-enhanced ultrasonography as an adjunctive method to ICG lymphography for functional lymphaticovenous anastomosis

BACKGROUND AND OBJECTIVES

Indocyanine green (ICG) lymphography is the reference standard for evaluating lymphedema stage and identifying lymphatic vessels. However, the penetration depth was limited to 1-2 cm from the skin surface. This prospective study compares clinical outcomes following lymphaticovenous anastomoses (LVA) in patients with upper and lower limb lymphedema using contrast-enhanced ultrasonography (CEUS) with ICG as a preoperative imaging modality.

METHODS

Under general anesthesia, Sonazoid® was injected subcutaneously to visualize functional lymphatic channels via CEUS. We analyzed the changes in limb circumference and inter-limb ratio (ILR) using bioimpedance to measure electrical resistance between the CEUS plus ICG group and the ICG-only group to see the effect of CEUS-assisted LVA.

RESULTS

No significant demographic differences existed between the two groups (CEUS plus ICG group vs. ICG-only group). The ILR decrease of the Z1 value measured using bioimpedance was statistically significant (p = 0.042 for the upper limb, p = 0.002 for the lower limb)- CONCLUSIONS: CEUS allowed us to identify deep-lying, functional, and large lymphatic channels. In conclusion, the combination of CEUS and ICG for identifying lymphatic channels has the potential to lead to a more functional lymphovenous anastomosis.

[Contrast-enhanced ultrasound (CEUS) and image fusion for procedures of liver interventions]

CLINICAL/METHODICAL ISSUE

Contrast-enhanced ultrasound (CEUS) is becoming increasingly important for the detection and characterization of malignant liver lesions and allows percutaneous treatment when surgery is not possible. Contrast-enhanced ultrasound image fusion with computed tomography (CT) and magnetic resonance imaging (MRI) opens up further options for the targeted investigation of a modified tumor treatment.

METHODICAL INNOVATIONS

Ultrasound image fusion offers the potential for real-time imaging and can be combined with other cross-sectional imaging techniques as well as CEUS.

PERFORMANCE

With the implementation of ultrasound contrast agents and image fusion, ultrasound has been improved in the detection and characterization of liver lesions in comparison to other cross-sectional imaging techniques. In addition, this method can also be used for intervention procedures. The success rate of fusion-guided biopsies or CEUS-guided tumor ablation lies between 80 and 100% in the literature.

ACHIEVEMENTS

Ultrasound-guided image fusion using CT or MRI data, in combination with CEUS, can facilitate diagnosis and therapy follow-up after liver interventions.

PRACTICAL RECOMMENDATIONS

In addition to the primary applications of image fusion in the diagnosis and treatment of liver lesions, further useful indications can be integrated into daily work. These include, for example, intraoperative and vascular applications as well applications in other organ systems.

Contrast-Enhanced Ultrasound Guided Biopsy of Undetermined Abdominal Lesions: A Multidisciplinary Decision-Making Approach

Aim. To investigate the value of contrast-enhanced ultrasound (CEUS) guided biopsy of undetermined abdominal lesions in multidisciplinary treatment (MDT) decision-making approach. Methods. Between Jan 2012 and Dec 2015, 60 consecutive patients (male, 37; female, 23; mean age, 51.3 years ± 14.6) who presented with undetermined abdominal lesions were included. CEUS and core needle percutaneous biopsy was performed under real-time CEUS guidance in all lesions. Data were recorded and compared with conventional ultrasound (US) guidance group (n = 75). All CEUS findings and clinical data were evaluated in MDT. Results. CEUS enabled the delimitation of more (88.3% versus 41.3%) and larger (14.1 ± 10.7 mm versus 32.3 ± 18.5 mm) nonenhanced necrotic areas. More inner (20.0% versus 6.7%) and surrounding (18.3% versus 2.7%) major vessels were visualized and avoided during biopsies. CEUS-guided biopsy increased the diagnostic accuracy from 93.3% to 98.3%, with correct diagnosis in 57 of 60 lesions (95.0%). The therapeutic plan was influenced by CEUS guided biopsies findings in the majority of patients (98.3%). Conclusion. The combination of CEUS guided biopsy and MDT decision-making approach is useful in the diagnostic work-up and therapeutic management.