Demarcation Line Assessment in Anatomical Liver Resection: An Overview

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.

Standardization of laparoscopic anatomic liver resection of segment 2 by the Glissonean approach

BACKGROUND

Anatomic liver resection (ALR) has been established to eliminate the tumor-bearing hepatic region with preservation of the remnant liver volume for liver malignancies. Recently, laparoscopic ALR has been widely applied; however, there are few reports on laparoscopic segmentectomy 2. This study aimed to present the standardization of laparoscopic segmentectomy 2 with surgical outcomes.

METHODS

This study included seven patients who underwent pure laparoscopic segmentectomy 2 by the Glissonean approach from January 2020 to December 2021. Four of them had hepatocellular carcinoma, two had colorectal liver metastasis, and one had hepatic angiomyolipoma, which was preoperatively diagnosed with hepatocellular carcinoma. In all patients, preoperative three-dimensional (3D) simulation images from dynamic CT were reconstructed using a 3D workstation. The layer between the hepatic parenchyma and the Glissonean pedicle of segment 2 (G2) was dissected to encircle the root of G2. After clamping or ligation of the G2, 2.5 mg of indocyanine green was injected intravenously to identify the boundaries between segments 2 and 3 with a negative staining method under near-infrared light. Parenchymal transection was performed from the caudal side to the cranial side according to the demarcation on the liver surface, and the left hepatic vein was exposed on the cut surface if possible.

RESULTS

The mean operative time for all patients was 281 min. The mean blood loss was 37 mL, and no transfusion was necessary. Estimated liver resection volumes significantly correlated with actual liver resection volumes (r = 0.61, P = 0.035). After the operation, one patient presented with asymptomatic deep venous and pulmonary thrombosis, which was treated with anticoagulant therapy. The mean length of hospital stay was 8.9 days.

CONCLUSION

Laparoscopic segmentectomy 2 by the Glissonean approach is a feasible and safe procedure with the preservation of the nontumor-bearing segment 3 for liver tumors in segment 2.

Landmarks to identify segmental borders of the liver: A review prepared for PAM-HBP expert consensus meeting 2021

BACKGROUND

In preparation for the upcoming consensus meeting in Tokyo in 2021, this systematic review aimed to analyze the current available evidence regarding surgical anatomy of the liver, focusing on useful landmarks, strategies and technical tools to perform precise anatomic liver resection (ALR).

METHODS

A systematic review was conducted on MEDLINE/PubMed for English articles and on Ichushi database for Japanese articles until September 2020. The quality assessment of the articles was performed in accordance with the Scottish Intercollegiate Guidelines Network (SIGN).

RESULTS

A total of 3169 manuscripts were obtained, 1993 in English and 1176 in Japanese literature. Subsequently, 63 English and 20 Japanese articles were selected and reviewed. The quality assessment of comparative series and case series was revealed to be usually low; only six articles were qualified as high quality. Forty-two articles focused on analyzing intersegmental/sectional planes and their relationship with specific hepatic landmark veins. In 12 articles, the authors aimed to investigate liver surface anatomic structures, while 36 articles aimed to study technological tools and contrast agents for surgical segmentation during ALR. Although Couinaud's classification has remained the cornerstone in daily diagnostic/surgical practices, it does not always portray the realistic liver segmentation and there has been no standardization on which a single strategy should be followed to perform precise ALR.

CONCLUSIONS

A global consensus should be pursued in order to establish clear guidelines and proper recommendations to perform ALR in the era of minimally invasive surgery.