Development of Hepatic Pseudotumors for Image-guided Interventional and Surgical Research in a Large Animal Model

Petre E, Marinelli B, Sarkar D, Barral M, H Cornelis F. Percutaneous liver interventions with robotic systems: a systematic review of available clinical solutions

OBJECTIVE

Robotic-guided interventions are emerging techniques that are gradually becoming a common tool for performing biopsies and tumor ablations in liver. This systematic review aims to evaluate their advancements, challenges, and outcomes.

METHODS

A systematic review was conducted using the PubMed database to identify relevant articles published between January 2000 and February 2023. Inclusion criteria focused on studies that assessed robotic systems for percutaneous liver biopsies and tumor ablations. Data extraction was performed to collect information on study characteristics; robotic systems; components and software; imaging modality; degree of freedom; and needle insertion methods. The outcome measures analyzed were procedure time, radiation dose, and accuracy.

RESULTS

10 studies met the inclusion criteria. The robotic devices used included MAXIO, EPIONE, ROBIO-EX, AcuBot, and ACE robotic systems. The data set consisted of 429 percutaneous thermal ablations and 57 biopsies, both robot-guided. On average, the mean deviation of probes was reduced by 30% (from 1.6 vs 3.3 mm to 2.4 vs 3.9 mm (p < 0.001)), and 40% (p < 0.05) fewer readjustments were required during the robotic-assisted interventions. Moreover, robotic systems contributed to a reduction in operating time, ranging from 15% (18.3 vs 21.7 min, p < 0.001) to 25% (63.5 vs 87.4 min, p < 0.001). Finally, the radiation dose delivered to both the patient and the operator was decreased by an average of 50% (p < 0.05) compared to manual procedures.

ADVANCES IN KNOWLEDGE

Robotic systems could provide precise navigation and guidance during liver biopsies and percutaneous ablations.

Image-Guided Surgical Simulation in Minimally Invasive Liver Procedures: Development of a Liver Tumor Porcine Model Using a Multimodality Imaging Assessment

Background: Image-guided liver surgery and interventions are growing as part of the current trend to translate liver procedures into minimally invasive approaches. Hands-on surgical training in such techniques is required. Consequently, a meaningful and realistic liver tumor model using multi-imaging modalities, such as ultrasound (US), computed tomography (CT), magnetic resonance (MR), cone beam-CT (CBCT), is mandatory. The first aim of this study is to develop a novel tumor-mimic model and assess it with multi-imaging modalities. The second aim is to evaluate the usefulness of the model during image-guided liver procedures. Materials and Methods: The tumor-mimic model is made of a composition of hydrogel, smashed muscle, and gadolinium contrast solution. Five ex vivo livers and three pigs were included in the study. Procedures were performed in an experimental hybrid operating room. Under general anesthesia, US guidance was required to inject the biotumor formula into the pig's liver. US, CT, CBCT, and MR acquisitions were then performed after the initial injection. In vivo models were then used to perform liver procedures, including US-guided biopsy, radiofrequency ablation, and laparoscopic resection. Results: The formula developed is easily injected generating a tissue-like material. Visualization using multi-imaging modalities was appropriate, thereby allowing to perform image-guided techniques. Conclusion: A novel design of an in vivo and ex vivo tissue-like tumor liver model is presented. Due to the multimodality imaging appraisal, it may provide a realistic and meaningful model allowing to perform image-guided liver procedures.

Performance of a Robotic Assistance Device in Computed Tomography-Guided Percutaneous Diagnostic and Therapeutic Procedures

PURPOSE

To evaluate a commercially available robotic assistance device for computed tomography-guided diagnostic and therapeutic interventions, compared to regular, manually performed CT scan-guided interventions in terms of precision, exposure to radiation to the patient and intervention time.

MATERIALS AND METHODS

Over a period of 6 months, 55 consecutive patients were recruited and treated using robotic assistance and compared to a control group of 101 patients previously treated with a regular CT scan-guided, manual approach. Evaluated parameters were precision (deviation from planned target and number of needle replacements), radiation exposure to the patient and intervention time. Evaluations were performed with regard to complexity (in-plane vs out-of-plane interventions) and type of anesthesia (general vs local).

RESULTS

Parameters related to precision were in general significantly better in the robotic assistance group (p < 0.01) with a mean deviation of 1.2 mm (± 1.6 mm) compared to 2.6 mm (± 1.1 mm) in the comparison group. Compared to manual procedure, the mean intervention time was reduced by 15 min (± 5.4 min) on average for an out-of-plane needle placement in the robotic group. There was no increase of exposure to radiation to the patient while radiation exposure for the physician was reduced to zero when the navigation system was used.

CONCLUSION

Compared to manual placement, the use of a robotic assistance device in out-of-plane CT-guided interventions under general anesthesia allows for probe placement with high precision. Intervention time is reduced with no increase of exposure to radiation to the patient.

Improving Echo-Guided Procedures Using an Ultrasound-CT Image Fusion System

INTRODUCTION

Image fusion between ultrasound (US) and computed tomography (CT) scan or magnetic resonance can increase operator accuracy in targeting liver lesions, particularly when those are undetectable with US alone. We have developed a modular gel to simulate hepatic solid lesions for educational purposes in imaging and minimally invasive ablation techniques. We aimed to assess the impact of image fusion in targeting artificial hepatic lesions during the hands-on part of 2 courses (basic and advanced) in hepatobiliary surgery.

MATERIALS AND METHODS

Under US guidance, 10 fake tumors of various sizes were created in the livers of 2 pigs, by percutaneous injection of a biocompatible gel engineered to be hyperdense on CT scanning and barely detectable on US. A CT scan was obtained and a CT-US image fusion was performed using the ACUSON S3000 US system (Siemens Healthcare, Germany). A total of 12 blinded course attendants, were asked in turn to perform a 10-minute liver scan with US alone followed by a 10-minute scan using image fusion.

RESULTS

Using US alone, the expert managed to identify all lesions successfully. The true positive rate for course attendants with US alone was 14/36 and 2/24 in the advanced and basic courses, respectively. The total number of false positives identified was 26. With image fusion, the rate of true positives significantly increased to 31/36 (P < .001) in the advanced group and 16/24 in the basic group (P < .001). The total number of false positives, considering all participants, decreased to 4 (P < .001).

CONCLUSIONS

Image fusion significantly increases accuracy in targeting hepatic lesions and might improve echo-guided procedures.