Usefulness of intraoperative ultrasonography in liver resections due to colon cancer metastasis

Navigating the Future of 3D Laparoscopic Liver Surgeries: Visualization of Internal Anatomy on Laparoscopic Images With Augmented Reality

INTRODUCTION

Liver tumor resection requires precise localization of tumors and blood vessels. Despite advancements in 3-dimensional (3D) visualization for laparoscopic surgeries, challenges persist. We developed and evaluated an augmented reality (AR) system that overlays preoperative 3D models onto laparoscopic images, offering crucial support for 3D visualization during laparoscopic liver surgeries.

METHODS

Anatomic liver structures from preoperative computed tomography scans were segmented using open-source software including 3D Slicer and Maya 2022 for 3D model editing. A registration system was created with 3D visualization software utilizing a stereo registration input system to overlay the virtual liver onto laparoscopic images during surgical procedures. A controller was customized using a modified keyboard to facilitate manual alignment of the virtual liver with the laparoscopic image. The AR system was evaluated by 3 experienced surgeons who performed manual registration for a total of 27 images from 7 clinical cases. The evaluation criteria included registration time; measured in minutes, and accuracy; measured using the Dice similarity coefficient.

RESULTS

The overall mean registration time was 2.4±1.7 minutes (range: 0.3 to 9.5 min), and the overall mean registration accuracy was 93.8%±4.9% (range: 80.9% to 99.7%).

CONCLUSION

Our validated AR system has the potential to effectively enable the prediction of internal hepatic anatomic structures during 3D laparoscopic liver resection, and may enhance 3D visualization for select laparoscopic liver surgeries.

Recent advances in computerized imaging and its vital roles in liver disease diagnosis, preoperative planning, and interventional liver surgery: A review

The earliest and most accurate detection of the pathological manifestations of hepatic diseases ensures effective treatments and thus positive prognostic outcomes. In clinical settings, screening and determining the extent of a pathology are prominent factors in preparing remedial agents and administering appropriate therapeutic procedures. Moreover, in a patient undergoing liver resection, a realistic preoperative simulation of the subject-specific anatomy and physiology also plays a vital part in conducting initial assessments, making surgical decisions during the procedure, and anticipating postoperative results. Conventionally, various medical imaging modalities, e.g., computed tomography, magnetic resonance imaging, and positron emission tomography, have been employed to assist in these tasks. In fact, several standardized procedures, such as lesion detection and liver segmentation, are also incorporated into prominent commercial software packages. Thus far, most integrated software as a medical device typically involves tedious interactions from the physician, such as manual delineation and empirical adjustments, as per a given patient. With the rapid progress in digital health approaches, especially medical image analysis, a wide range of computer algorithms have been proposed to facilitate those procedures. They include pattern recognition of a liver, its periphery, and lesion, as well as pre- and postoperative simulations. Prior to clinical adoption, however, software must conform to regulatory requirements set by the governing agency, for instance, valid clinical association and analytical and clinical validation. Therefore, this paper provides a detailed account and discussion of the state-of-the-art methods for liver image analyses, visualization, and simulation in the literature. Emphasis is placed upon their concepts, algorithmic classifications, merits, limitations, clinical considerations, and future research trends.

Routine Intraoperative Ultrasound for the Detection of Liver Metastases during Resection of Primary Colorectal Cancer - A Systematic Review

During the discovery of ColoRectal Cancer (CRC), 20% to 30% of patients have synchronous liver metastases. Ten to 30% of patients have non-evidence of Liver Metasteses (LM) following preoperative imaging such as Contrast-Enhanced Ultrasound (CE-US), multi-slice Contrast-Enhanced Computed Tomography (CE-CT), Contrast-Enhanced Magnetic Resonance Imaging (CE-MRI), and Positron Emission Tomography-Computed Tomography (PET-CT). Today, IntraOperative UltraSound (IOUS) in open surgery and Laparoscopic UltraSound (LUS) in laparoscopic or robotic surgery are considered the "gold standard" for detecting liver metastases. The object of this review is to demonstrate the higher sensitivity and specificity of IOUS and LUS in the detection rate of liver metastases.

The actual management of colorectal liver metastases

Colorectal cancer is one of the most frequent cancers in the world and between 50% and 60% of patients will develop colorectal liver metastases (CRLM) during the disease. There have been great improvements in the management of CRLM during the last decades. The combination of modern chemotherapeutic and biological systemic treatments with aggressive surgical resection strategies is currently the base for the treatment of patients considered unresectable until few years ago. Furthermore, several new treatments for the local control of CRLM have been developed and are now part of the arsenal of multidisciplinary teams for the treatment of these complex patients. The aim of this review was to summarize and update the management of CRLM, its controversies and relevant evidence.

Application of image-guided navigation system for laparoscopic hepatobiliary surgery

BACKGROUND

To achieve safety of the operation, preoperative simulation became a routine practice for hepatobiliary and pancreatic (HBP) surgery. The use of intraoperative ultrasonography (IOUS) is essential in HBP surgery. There is a limitation in the use of IOUS in laparoscopic surgery (LS), for which a new intraoperative system is expected. We have developed an image-guided navigation system (IG-NS) for open HBP surgery since 2006, and we have applied our system to LS. The aim of this study is to evaluate the results of clinical application of IG-NS in LS.

MATERIALS AND METHODS

Eight patients underwent LS using IG-NS; LS consisted of cholecystectomy and hepatectomy in four patients each. After registration, the 3D models were superimposed on the surgical field. We performed LS while observing the navigation image. Moreover, we developed a support system for operations.

RESULTS

The average registration error was 8.8 mm for LS. Repeated registration was effective for organ deformation and improved the precision of IG-NS. By using various countermeasures, identification of the tumor's position and the setting of the resection line became easy.

CONCLUSION

As IG-NS provided real-time detailed and intuitive information, this intraoperative assist system may be an effective tool in LS.

Intraoperative Ultrasound Staging for Colorectal Liver Metastases in the Era of Liver-Specific Magnetic Resonance Imaging: Is It Still Worthwhile?

Background

To assess the efficacy of intraoperative ultrasound (IOUS) compared with liver-specific magnetic resonance imaging (MRI) in patients with colorectal liver metastases (CRLMs).

Methods

From January 2010 to December 2017, 721 patients underwent MRI as a part of preoperative workup within 1 month before hepatectomy and were considered for the study. Early intrahepatic recurrence (relapse at cut surface excluded) was assessed 6 months after the resection and was considered as residual disease undetected by IOUS and/or MRI. IOUS and MRI performance was compared on a patient-by-patient basis. Long-term results were also studied.

Results

A total of 2845 CRLMs were detected by MRI, and the median number of CRLMs per patient was 2 (1–31). Preoperative chemotherapy was administered in 489 patients (67.8%). In 177 patients, 379 new nodules were intraoperatively found and resected. Among 379 newly identified nodules, 317 were histologically proven CRLMs (11.1% of entire series). The median size of new CRLMs was 6 ± 2.5 mm. Relationships between intrahepatic vessels and tumors differed between IOUS and MRI in 128 patients (17.7%). The preoperative surgical plan was intraoperatively changed for 171 patients (23.7%). Overall, early intrahepatic recurrence occurred in 8.7% of cases. To assess the diagnostic performance, 24 (3.3%) recurrences at the cut surface were excluded; thus, 5.4% of early relapses were considered for analysis. The sensitivity of IOUS was superior to MRI (94.5% vs 75.1%), while the specificity was similar (95.7% vs 95.9%). Multivariate analysis at the hepatic dome or subglissonian and mucinous histology revealed predictive factors of metastases missing at MRI. The 5-year OS (52.1% vs 37.8%, p=0.006) and DF survival (45.1% vs 33%, p=0.002) were significantly worse among patients with new CRLMs than without.

Conclusions

IOUS improves staging in patients undergoing resection for CRLMs even in the era of liver-specific MRI. Intraoperative detection of new CRLMs negatively affects oncologic outcomes.

Improvement in the diagnosis and treatment of T2 gallbladder carcinoma is pivotal to improvement in the overall prognosis for this disease

Since the American Joint Committee on Cancer (AJCC) subdivided the T2 stage of gallbladder carcinoma (GBC) into T2a and T2b, the diagnosis and treatment of those stages have been a subject of heated discussion and controversy. T2 is a stage of GBC that might be treatable. Based on the extent of lymph node metastasis and distant metastasis, T2 GBC can be classified into various pathological stages such as IIA, IIB, IIIB, and IVB, leading to controversy in clinical settings. This review aims to discuss the effectiveness of and controversies concerning S4b+5 resection, the acceptable extent of lymph node dissection, the timing for treatment of incidental gallbladder cancer, and adjuvant therapy. This review also aims to suggest directions for and recommendations regarding clinical research in the future.

Multidisciplinary approach of colorectal cancer liver metastases

Large bowel cancer is a worldwide public health challenge. More than one third of patients present an advanced stage of disease at diagnosis and the liver is the most common site of metastases. Selection criteria for early diagnosis, chemotherapy and surgery have been recently expanded. The definition of resectability remains unclear. The presence of metastases is the most significant prognostic factor. For this reason the surgical resection of hepatic metastases is the leading treatment. The most appropriate resection approach remains to be defined. The two step and simultaneous resection processes of both primary and metastases have comparable survival long-term outcomes. The advent of targeted biological chemotherapeutic agents and the development of loco-regional therapies (chemoembolization, thermal ablation, arterial infusion chemotherapy) contribute to extend favorable results. Standardized evidence-based protocols are missing, hence optimal management of hepatic metastases should be single patient tailored and decided by a multidisciplinary team. This article reviews the outcomes of resection, systemic and loco-regional therapies of liver metastases originating from large bowel cancer.