Augmented Reality Navigation Plus Indocyanine Green Fluorescence Imaging Can Accurately Guide Laparoscopic Anatomical Segment 8 Resection

Development of real-time navigation system for laparoscopic hepatectomy using magnetic micro sensor

BACKGROUND

We report a new real-time navigation system for laparoscopic hepatectomy (LH), which resembles a car navigation system.

MATERIAL AND METHODS

Virtual three-dimensional liver and body images were reconstructed using the "New-VES" system, which worked as roadmap during surgery. Several points of the patient's body were registered in virtual images using a magnetic position sensor (MPS). A magnetic transmitter, corresponding to an artificial satellite, was placed about 40 cm above the patient's body. Another MPS, corresponding to a GPS antenna, was fixed on the handling part of the laparoscope. Fiducial registration error (FRE, an error between real and virtual lengths) was utilized to evaluate the accuracy of this system.

RESULTS

Twenty-one patients underwent LH with this system. Mean FRE of the initial five patients was 17.7 mm. Mean FRE of eight patients in whom MDCT was taken using radiological markers for registration of body parts as first improvement, was reduced to 10.2 mm (p = .014). As second improvement, a new MPS as an intraoperative body position sensor was fixed on the right-sided chest wall for automatic correction of postural gap. The preoperative and postoperative mean FREs of 8 patients with both improvements were 11.1 mm and 10.1 mm (p = .250).

CONCLUSIONS

Our system may provide a promising option that virtually guides LH.

A pilot study of virtual liver segment projection technology in subsegment-oriented laparoscopic anatomical liver resection when indocyanine green staining fails (with video)

BACKGROUND

Precision surgery for liver tumors favors laparoscopic anatomical liver resection (LALR), involving the removal of specific liver segments or subsegments. Indocyanine green (ICG)-negative staining is a commonly used method for defining resection boundaries but may be prone to failure. The challenge arises when ICG staining fails, as it cannot be repeated during surgery. In this study, we employed the virtual liver segment projection (VLSP) technology as a salvage approach for precise boundary determination. Our aim was to assess the feasibility of the VLSP to be used for the determination of the boundaries of the liver resection in this situation.

METHODS

Between January 2021 and June 2023, 12 consecutive patients undergoing subsegment-oriented LALR were included in this pilot series. The VLSP technology was utilized to define the resection boundaries at the time of ICG-negative staining failure. Routine surgical parameters and short-term outcomes were evaluated to assess the safety of VLSP in this procedure. In addition, its feasibility was assessed by analyzing the accuracy between the predicted resected liver volume (PRLV) and actual resected liver volume (ARLV).

RESULTS

Of the 12 enrolled patients, the mean operation time was 444.58 ± 101.70 min (range 290-570 min), with a mean blood loss of 125.00 ± 96.53 ml (range 50-400 mL). One patient (8.3%) was converted to laparotomy for subsequent parenchymal transection, four (33.3%) received blood transfusions and four (33.3%) had postoperative complications. All patients received an R0 resection. The Pearson correlation coefficient (r) between PRLV and ARLV was 0.98 (R2 = 0.96, p < 0.05), and the relative error (RE) was 8.62 ± 6.66% in the 12 patients, indicating agreement.

CONCLUSION

Failure of intraoperative ICG-negative staining during subsegment-oriented LALR is possible, and VLSP may be an alternative to define the resection boundaries in such cases.

Laparoscopic left hemihepatectomy using augmented reality navigation plus ICG fluorescence imaging for hepatolithiasis: a retrospective single-arm cohort study (with video)

BACKGROUND

Laparoscopic left hemihepatectomy (LLH) has been shown to be an effective and safe method for treating hepatolithiasis primarily affecting the left hemiliver. However, this procedure still presents challenges. Due to pathological changes in intrahepatic duct stones, safely dissecting the hilar vessels and determining precise resection boundaries remains difficult, even with fluorescent imaging. Our team proposed a new method of augmented reality navigation (ARN) combined with Indocyanine green (ICG) fluorescence imaging for LLH in hepatolithiasis cases. This study aimed to investigate the feasibility of this combined approach in the procedure.

METHODS

Between May 2021 and September 2023, 16 patients with hepatolithiasis who underwent LLH were included. All patients underwent preoperative 3D evaluation and were then guided using ARN and ICG fluorescence imaging during the procedure. Perioperative and short-term postoperative outcomes were assessed to evaluate the safety and efficacy of the method.

RESULTS

All 16 patients successfully underwent LLH. The mean operation time was 380.31 ± 92.17 min, with a mean estimated blood loss of 116.25 ± 64.49 ml. ARN successfully aided in guiding hilar vessel dissection in all patients. ICG fluorescence imaging successfully identified liver resection boundaries in 11 patients (68.8%). In the remaining 5 patients (31.3%) where fluorescence imaging failed, virtual liver segment projection (VLSP) successfully identified their resection boundaries. No major complications occurred in any patients. Immediate stone residual rate, stone recurrence rate, and stone extraction rate through the T-tube sinus tract were 12.5%, 6.3%, and 6.3%, respectively.

CONCLUSION

The combination of ARN and ICG fluorescence imaging enhances the safety and precision of LLH for hepatolithiasis. Moreover, ARN may serve as a safe and effective tool for identifying precise resection boundaries in cases where ICG fluorescence imaging fails.

Detection and Real-Time Surgical Assessment of Colorectal Liver Metastases Using Near-Infrared Fluorescence Imaging during Laparoscopic and Robotic-Assisted Resections

BACKGROUND

The European Association of Endoscopic Surgery (EAES) recommends, with strong evidence, the use of indocyanine green (ICG) fluorescence imaging combined with intraoperative ultrasound (IOUS) to improve identification of superficial liver tumors. This study reports the use of ICG for the detection of colorectal liver metastases (CRLMs) during minimally invasive liver resection.

METHODS

A single-center consecutive series of minimally invasive (laparoscopic and robotic) hepatic resections for CRLMs was prospectively evaluated (April 2019 and October 2023).

RESULTS

A total of 25 patients were enrolled-11 undergoing laparoscopic and 14 undergoing robotic procedures. The median age was 65 (range 50-85) years. Fifty CRLMs were detected: twenty superficial, eight exophytic, seven shallow (<8 mm from the hepatic surface), and fifteen deep (>10 mm from the hepatic surface) lesions. The detection rates of CRLMs through preoperative imaging, laparoscopic ultrasound (LUS), ICG fluorescence, and combined modalities (ICG and LUS) were 88%, 90%, 68%, and 100%, respectively. ICG fluorescence staining allowed us to detect five small additional superficial lesions (not identified with other preoperative/intraoperative techniques). However, two lesions were false positive fluorescence accumulations. All rim fluorescence pattern lesions were CRLMs. ICG fluorescence was used as a real-time guide to assess surgical margins during parenchymal-sparing liver resections. All patients with integrity of the fluorescent rim around the CRLM displayed a radical resection during histopathological analysis. Four patients (8%) with a protruding rim or residual rim patterns had positive resection margins.

CONCLUSIONS

ICG fluorescence imaging can be integrated with other conventional intraoperative imaging techniques to optimize intraoperative staging. Rim fluorescence proved to be a valid indicator of the resection margins: by removing the entire fluorescent area, a tumor-negative resection (R0) is achieved.