Measuring intraoperative anesthetic parameters during hepatectomy with inferior vena cava clamping.

PURPOSE: Uncontrollable bleeding remained problematic in anatomical hepatectomy exposing hepatic veins. Based on the inferior vena cava (IVC) anatomy, we attempted to analyze the hemodynamic and surgical effects of the combined IVC-partial clamp (PC) accompanied with the Trendelenburg position (TP). METHODS: We prospectively assessed 26 consecutive patients who underwent anatomical hepatectomies exposing HV trunks between 2020 and 2023. Patients were divided into three groups: use of IVC-PC (group 1), no use of IVC-PC (group 2), and use of IVC-PC accompanied with TP (group 3). In 10 of 26 patients (38%), hepatic venous pressure was examined using transhepatic catheter insertion. RESULTS: IVC-PC was performed in 15 patients (58%). Operating time and procedures did not significantly differ between groups. A direct hemostatic effect on hepatic veins was evaluated in 60% and 70% of patients in groups 1 and 3, respectively. Group 1 showed significantly more unstable vital status and vasopressor use (p < 0.01). Blood or fluid transfusion and urinary output were similar between groups. Group 2 had a significantly lower baseline central venous pressure (CVP), while group 3 showed a significant increase in CVP in TP. CVP under IVC-PC seemed lower than under TP; however, not significantly. Hepatic venous pressure did not significantly differ between groups. Systolic arterial blood pressure significantly decreased via IVC-PC in group 1 and to a similar extent in group 3. Heart rate significantly increased during IVC-PC (p < 0.05). CONCLUSION: IVC-PC combined with the TP may be an alternative procedure to control intrahepatic venous bleeding during anatomical hepatectomy exposing hepatic venous trunks.

Novel analysis using magnetic resonance cholangiography for patients with pancreaticobiliary maljunction.

PURPOSE: We used a novel diagnostic Fourier transform (FT) algorithm of the entire extrahepatic bile duct (EHBD) measured by magnetic resonance cholangiography (MRC) to evaluate subtle deformation of bile duct lumen, indicating the malignant potential of EHBD, in patients with pancreaticobiliary maljunction (PBMJ) and in a comparative group of controls without PBMJ. METHODS: From the workstation, the EHBD lumen was traced automatically and a 2D diagram cross section was measured at 0.5 mm-longitudinal intervals. The FT-based integrated power spectral density function value (FTPSDI) of the diameter or area (mm2 or mm4/Hz) and the phase value distribution entropy (PVDE) were also measured. RESULTS: There were 16 patients with undilated PBMJ and 7 with dilated PBMJ. The control group comprised 10 patients with a normal bile duct, 20 with bile duct carcinoma (BDC), and 1 with primary sclerosing cholangitis. Both the diameter and area of the dilated bile ducts and the ducts with early- or advanced-stage BDC were significantly greater than those of the normal duct (p < 0.05). The undilated type of PBMJ tended to have a larger FTPSDI diameter than a normal bile duct, which had a smaller diameter than the dilated type of PBMJ or BDC. BDC had a significantly larger FTPSDI diameter (p < 0.05) and the cutoff value for accuracy was 168 mm2 Hz-1. CONCLUSION: The novel mathematical FTPSDI is a promising indicator of whether preventive EHBD resection is necessary for patients with PBMJ, which can be widely applied in the early diagnosis of other biliary diseases.

Using indocyanine green fluorescence in laparoscopic surgery to identify and preserve rare branching of the right hepatic artery in pediatric congenital biliary dilatation.

We describe a laparoscopic surgical technique using indocyanine green (ICG) fluorescence to identify and preserve rare arterial branching associated with pediatric congenital biliary dilatation. Congenital biliary dilatation with pancreaticobiliary maljunction was diagnosed in a 9-year-old girl, who presented with upper abdominal pain. Abdominal enhanced computed tomography (CT) showed that the accessory right hepatic artery (aRHA) branched from the posterior superior pancreaticoduodenal artery (PSPDA) and flowed through the right aspect of the dilated common bile duct (CBD) directly into the right lobe of the liver. We performed laparoscopic dilated biliary duct resection and hepaticojejunostomy, administering ICG intravenously, at a dose of 0.6 mg/kg. The ICG fluorescence overlay mode showed an aRHA running along the right side of the dilated CBD. The aRHA was dissected from the CBD without injury. After finishing the anastomosis, the beating of the aRHA was preserved, confirming that blood flow had been maintained.

Relationship between hepatic venous anatomy and hepatic venous blood loss during hepatectomy.

PURPOSE: Predicting increased blood loss based on anatomical intervascular relationships is essential in major hepatectomy. METHODS: We assessed 63 consecutive patients undergoing anatomical hepatectomy exposing the hepatic vein (HV) trunk at two institutes. Correlations between anatomical alterations of the hepatic inferior vena cava (IVC), HV, hepatic IVC, or right atrium (RA) and the blood loss per standard weight (BLSW) or blood transfusion (n = 18) were analyzed. The results of IVC partial clamping (PC) were additionally examined. RESULTS: The BLSW in type V-up anatomical morphology was significantly higher than that in straight type (p < 0.05). The parameters associated with an increased BLSW (> 13.5 mL/kg) were tumor size (> 4 cm), prothrombin activity (< 87%), CVP (> 7 mmHg), area of suprahepatic IVC (< 360 mm2), IVC-RA gap (> 28 mm), longitudinal angle of IVC (< 160°), and axial angle of the MHV (< 55°). A multivariate analysis revealed that a high IVC-RA gap was a significant independent risk factor (odds ratio; 4.32, p < 0.05). Among 25 patients undergoing IVC-PC, only three showed a remarkable decrease in hepatic venous bleeding. No other statistically significant differences in the surgical records were observed in most cases. CONCLUSION: The IVC-RA gap might be a promising novel predictive parameter reflecting increased blood loss leading to blood transfusion in anatomical hepatectomy.

Neutrophil-to-Lymphocyte Ratio and Intratumoral CD45RO-Positive T Cells as Predictive Factors for Longer Survival of Patients with Colorectal Liver Metastasis after Hepatectomy.

Colorectal cancer is the fourth most common malignancy across the world, and over 50% of patients had colorectal liver metastases (CLM). Activated neutrophils and tumor-infiltrating lymphocytes (TILs) are considered to interrupt progression of primary colorectal cancer; however, immunological host reactions to CLM have not been fully elucidated. We thus aimed to explore the prognostic implication of neutrophil-to-lymphocyte ratio (NLR) in peripheral blood and TILs in resected metastatic cancer tissues of 29 patients with CLM who underwent hepatectomy. To evaluate local immunological responses in CLM, we examined the infiltration of CD66b+ neutrophils and TILs, such as CD8+ T cells, CD45RO+ T cells, and forkhead box P3+ (FOXP3+) T cells. The presence of fewer than 4 tumors (p = 0.0005), the absence of distant metastasis (p = 0.018), adjuvant anti-cancer chemotherapy (p = 0.0013), and elevated NLR over 4.1 (p = 0.026) were found to be significant parameters related to longer survival after hepatectomy. Further, high numbers of infiltrated CD45RO+ T cells in CLM were significantly associated with longer patient survival (p = 0.020). The numbers of CD45RO+ T cells were correlated with those of CD8+ T cells (p = 0.008). The numbers of peripheral blood neutrophils were negatively correlated with those of CD45RO+ T cells (p = 0.038) and of CD66b+ neutrophils (p = 0.008) in CLM. The present data indicate that elevated peripheral blood NLR and high numbers of intratumoral CD45RO+ T cells are predictive of longer CLM patient survival after hepatectomy among current biomarkers.

The successful posterior sectionectomy accompanied with caudate lobectomy for hepatocellular carcinoma located in segment 1 after LEN-TACE: a case report.

Nowadays, the novel molecular targeting chemotherapy provides possibility of safe hepatectomy for progressive hepatocellular carcinoma (HCC). Further, combination of the conventional transarterial chemoembolization (TACE) may add an effect of tumor shrink. We present a successful radical hepatectomy for a large HCC located in segment 1 accompanied with the preoperative Lenvatinib (LEN)-TACE sequential treatment. We present a woman patient without any complaints who had a 7 cm-in-size of solitary HCC compressing vena cava and right portal pedicle. To achieve radical hepatectomy by tumor shrinking, LEN-TACE for 2 months. After confirming downsizing or devascularization of the HCC, we scheduled radical posterior sectionectomy combined with caudate lobectomy according to tumor location and expected future remnant liver volume from three-dimensional computed tomography simulation before surgery. Under the thoraco-abdominal incision laparotomy, we safely achieved scheduled radical hepatectomy without any vascular injuries. The postoperative course was uneventful and no tumor recurrence were observed for 1 year. Histological findings showed the Japan TNM stage III HCC with 70% necrosis. The multi-modal strategy of LEN-TACE followed by radical hepatectomy by confirming downsizing or devascularization in tumor is supposed to be useful and would be a preoperative chemotherapy option, and promising for curative treatment in HCC patients with progressive or large HCC, which may lead to safety by prevention surrounding major vascular injury.

Acceptance of Virtual Reality Simulation Training for Stoma Care by Healthcare Providers: A Pilot Questionnaire Study After Viewing Prototype Imagings.

OBJECTIVES:  Educational simulation systems using virtual reality (VR) with head-mounted devices are spreading into the medical field. We developed an innovative training system whereby experienced ostomates can share their proficient stoma self-care techniques with novice ostomates through VR simulations, enabling anytime, anywhere learning. We examined the questionnaire study to assess the acceptance of VR simulation training for stoma care by healthcare providers. METHODS: This study was conducted for the participants, nurses, and doctors, at the 39th Kyushu Stoma Rehabilitation Research Meeting with the organizer's permission. We created two VR simulation prototypes from the perspective of ostomates and caregivers using modeled stomas. We conducted a qualitative study through a questionnaire with healthcare professionals regarding their experiences of viewing VR videos. RESULTS: The study included 20 (52.6%) nurses certified in wound, ostomy, and continence (WOC) care, 16 (42.1%) non-WOC nurses, and two (5.3%) medical doctors. Over 90% of participants showed a positive inclination towards the practical application of the system in clinical settings for both scenarios. A significantly higher number of nurses in the non-WOC nurse group expressed a definite interest in using the imaging from the ostomate's perspective versus that in the WOC nurse group (81.3% vs. 40%, P=0.013). CONCLUSIONS: From this survey, we concluded that the respondents felt a VR training system was a positive experience, to say it is acceptable means that it was as good as the standard of care. ​​​​​​Particularly, non-WOC nurses, with fewer opportunities in stoma care compared to WOC nurses, showed stronger interest in practically implementing this innovative training system.

A case of multifocal sclerosis angiomatoid nodular transformations of the spleen occurring after partial splenic infarction with transcatheter arterial embolization for splenic artery aneurysm.

A 48-year-old woman underwent transcatheter arterial embolization (TAE) for a splenic artery aneurysm, which resulted in a partial splenic infarction in the middle lobe. Five years after TAE, a 20-mm diameter mass in the noninfarcted area of the spleen was detected on imaging, which grew to 25 mm in diameter after 6 months. MRI after gadolinium administration showed a 35 × 34 mm mass within the superior pole and 15 × 12 mm mass within the inferior pole. The patient underwent laparoscopic splenectomy and had an uneventful postoperative recovery. No evidence of recurrence was observed during the 2-year follow-up period after surgery. The mass was pathologically confirmed to be sclerosing angiomatoid nodular transformation (SANT) of the spleen. While some studies hypothesize that SANT is a response to vascular injury or trauma, to the best of our knowledge, there have been no previous reports of SANT occurring after procedures directly affecting splenic blood flow. Additionally, multifocal SANTs are reported to be very rare, accounting for only 4.7% of all reported SANTs of the spleen. We highlight a rare course of SANT of the spleen and discuss the possible relationship between blood flow abnormalities and the appearance of SANT.

An unusual presentation of a rare formation of the common hepatic duct and right hepatic artery in a case of pediatric congenital biliary dilatation.

A 15-year-old girl with recurrent upper abdominal pain was diagnosed with congenital biliary dilatation. Abdominal enhanced computed tomography (CT) showed the anterior segmental branch of the right hepatic artery (RHA) running across the ventral aspect of the dilated common hepatic duct (CHD). Laparoscopic extrahepatic dilated biliary duct excision and Roux-en-Y hepaticojejunostomy were planned. Intraoperatively, the dilated CHD was observed to bifurcate into the ventral and dorsal ducts, between which the anterior segmental branch of the RHA crossed through the CHD. The CHD rejoined on the distal side as one duct. We transected the CHD just above the cystic duct. The patency of the ventral and dorsal sides of the bifurcated CHD was confirmed. Laparoscopic hepaticojejunostomy was performed at the distal side of the rejoined CHD, without sacrificing the anterior segmental branch of the RHA. There was no postoperative blood flow impairment in the right hepatic lobe or anastomotic stenosis.

MANGOU (Miyazaki Advanced New General Surgery of University) Wet Lab Training Relieves Anxiety About Surgical Skills in Surgical Education: A Cross-Sectional Study.

PURPOSE: To increase the number of medical students or residents who want to become surgeons, we must evaluate our program that recruits new young surgeons. METHODS: We planned surgical training programs for medical students and residents that we named the MANGOU (Miyazaki Advanced New General surgery Of University) training project in the Department of Surgery, Miyazaki University, Japan. From January 2016 through December 2022, we asked trainees who attended this training to complete questionnaires to evaluate their interest in surgery, confidence in surgical skills, and training. Scoring of the questionnaire responses was based on a 5-point Likert scale, and we evaluated this training prospectively. RESULTS: Among the 109 trainees participating in this training, 61 answered the questionnaires. Two participants found the training boring, but 59 (96.7%) enjoyed it. All of them answered "Yes" to wanting to participate in the next training. Respective pre- and post-training scores were as follows: confidence in surgical skills, 2.2 ± 1.0 and 3.0 ± 1.0 (p < 0.0001); interest in surgery, 4.2 ± 0.8 and 4.4 ± 0.5 (p = 0.0011); and willingness to become surgeons, 3.9 ± 0.7 and 4.1 ± 0.6 (p = 0.0011). All scores rose after MANGOU training. CONCLUSION: We planned MANGOU surgical wet lab training for medical students and residents that aimed to educate and recruit new surgeons. After joining the MANGOU training, the trainees' anxiety about surgery was reduced, their confidence in performing surgical procedures improved, they showed more interest in surgery, and they increased their motivation to become surgeons.

Clinical significances of several fibrotic markers for prognosis in hepatocellular carcinoma patients who underwent hepatectomy.

Background: Progression of chronic liver fibrosis and related increased fibrotic markers are associated with functional liver reserves or patient prognosis as well as tumor factors in hepatocellular carcinoma (HCC) patients. The aim of this study was to newly clarify the relationship between fibrotic markers and HCC malignant behaviors or its long-term postoperative prognosis by the retrospective cohort study. Methods: We examined the relationship between tumor-related factors or six liver fibrosis-associated parameters, including platelet count, hyaluronic acid (HA), Mac-2 binding protein glycosylation isomer (M2BPGi), type IV collagen 7S (T4C7), aspartate aminotransferase-to-platelet ratio index (APRI), fibrosis-4 (Fib-4) index, and clinicopathological parameters, surgical records, and postoperative prognosis in 130 HCC who underwent curative hepatectomy. Results: Histological fibrosis stage 4 as cirrhosis was in 31%. The platelet count significantly decreased in stage 4 fibrosis and correlated with grade B liver damage (P<0.01). HA levels were significantly increased in multiple HCC, stage 4 fibrosis, and grade B liver damage (P<0.01). T4C7 was significantly increased in patients with post-hepatectomy tumor recurrence compared to those without (P<0.01). Additionally, M2BPGi was significantly higher in stage 4 fibrosis and liver damage grade B, and was significantly associated with poor prognosis (P<0.05). Fib-4 index was significantly higher in patients with liver damage B (P<0.05), and T4C7 alone did not correlate with other five fibrosis markers. Stage 4 fibrosis, higher T4C7, higher M2BPGi, and increased tumor size were significantly associated with shorter cancer-free, overall, and cancer-specific survivals. Higher T4C7, non-met Milan criteria, liver damage B, blood transfusion, and curability C were independently associated with cancer-specific survivals (P<0.05). Conclusions: Type IV collagen 7S (T4C7) may reflect not only impaired liver function but also HCC malignant behaviors and patient survivals.

Clinical Impact of the Charlson Comorbidity Index on the Efficacy of Salvage Photodynamic Therapy Using Talaporfin Sodium for Esophageal Cancer.

Introduction Photodynamic therapy (PDT) is a salvage treatment for local failure after chemoradiotherapy for esophageal cancer. Salvage PDT is the treatment available for vulnerable patients with various comorbidities at risk of salvage esophagectomy. This study assessed the impact of the Charlson comorbidity index (CCI) on the outcomes of salvage PDT using talaporfin sodium (TS) for esophageal cancer. Metohds Consecutive patients with esophageal cancer who underwent salvage TS-PDT from 2016 to 2022 were included in this retrospective study. We investigated the local complete response (L-CR), progression-free survival (PFS) and overall survival (OS) and evaluated the relationship between the CCI and therapeutic efficacy. Results In total, 25 patients were enrolled in this study. Overall, 12 patients (48%) achieved an L-CR, and the 2-year PFS and OS rates were 24.9% and 59.4%, respectively. In a multivariate analysis, a CCI ≥1 (p=0.041) and deeper invasion (p=0.048) were found to be significant independent risk factors for not achieving an L-CR. To evaluate the efficacy associated with comorbidities, we divided the patients into the CCI=0 group (n=11) and the CCI ≥1 group (n=14). The rate of an L-CR (p=0.035) and the 2-year PFS (p=0.029) and OS (p=0.018) rates in the CCI ≥1 group were significantly lower than those in the CCI=0 group. Conclusion This study found that the CCI was negatively associated with the efficacy of salvage TS-PDT for esophageal cancer.

Retroperitoneal-first dissection approach at the dorsal space for a huge serous cystic neoplasm of the pancreatic tail: a case report.

BACKGROUND: Large tumors of serous cystic adenomas in the pancreatic body-to-tail severely compress the surrounding organs and retroperitoneal space. CASE PRESENTATION: We present a unique surgical challenge for distal pancreatectomy (DP). We present the case of a patient who had a massive mass lesion measuring more than 20 cm in size that had been misdiagnosed as a retroperitoneal tumor by the previous hospital. However, an expert radiologist at our institute diagnosed serous cystadenoma of the pancreas based on imaging characteristics. We decided to perform retroperitoneal space first dissection using a small incision because we were concerned about tumor infiltration or compressive adhesions in important retroperitoneal vessels. We safely attempted distal pancreatectomy by limiting the laparotomy incision step-by-step while securing the main vascular injury of the retroperitoneum. In addition to the ordinary cooperation with urological surgeons, this technique is referred to by the concept of retroperitoneal procedures for minimally invasive surgery in urology. CONCLUSIONS: This approach is useful for lifting resected specimens by prior and wide retroperitoneal dissection, which may lead to safety and the prevention of unexpected vascular injury.

A Preliminary Pathological Evaluation of Extracellular Volume Fraction with Contrast-enhanced Computed Tomography as a Novel Quantitative Parameter of Pancreatic Fibrosis.

Objective The extracellular volume (ECV) calculated based on contrast-enhanced computed tomography (CT) has been reported as a novel imaging parameter reflecting the morphological change of fibrosis in several parenchymal organs. Our retrospective study assessed the validity of the ECV fraction for diagnosing pancreatic fibrosis and the appropriate imaging condition as the "equilibrium phase". Methods In 27 patients undergoing multiphasic CT and subsequent pancreaticoduodenectomy, we investigated pathological fibrotic changes related to the ECV fraction and conducted analyses using the value obtained by subtracting the equilibrium CT value of the portal vein from that of the abdominal aorta (Ao-PVequilibrium) to estimate eligibility of the equilibrium phase. Results In all patients, the ECV fraction showed a weak positive correlation with the collagenous compartment ratio (r=0.388, p=0.045). All patients were divided into two groups - the high-Ao-PVequilibrium group and low-Ao-PVequilibrium group - based on the median value. No significant correlation was found in the high-Ao-PVequilibrium group, whereas a significant correlation was observed in the low-Ao-PVequilibrium group (r=0.566, p=0.035). Conclusion The ECV fraction is a possible predictive factor for histopathological pancreatic fibrosis. In its clinical application, the eligibility of the "equilibrium phase" may affect the diagnostic capability. It will be necessary to verify the imaging conditions in order to improve the accuracy of the diagnosis.

An alternative option of the retroperitoneal laparoscopic approach for limited hepatectomy for recurrent hepatocellular carcinoma at the transected edge after previous hepatectomy.

Laparoscopic hepatectomy is safely performed with minimal invasiveness on patients with recurrent liver tumors after previous hepatectomy. However, it is still difficult to dissect and expose the operative field at the transected edge or plane after open right hepatectomy, even for limited resection by a laparoscopic approach, due to severe adhesion to the surrounding peritoneum or organs. We herein applied the retroperitoneal laparoscopic approach to limited resection of the dorsal surface at the transected edge of Couinaud's segment 6 after previous repeated hepatectomies in a patient with recurrent hepatocellular carcinoma (HCC) by avoiding severe intra-abdominal adhesion. We safely resected recurrent HCC via the retroperitoneal space. This approach is a useful and alternative option for laparoscopy which minimizes the dissecting time and avoids organ injury on the right side of the transected area of the liver after hepatectomy in patients with liver malignancies.

Questionnaire survey of virtual reality experiences of digestive surgery at a rural academic institute: A pilot study for pre-surgical education.

We developed a prototype VR platform, VECTORS L&M (VLM), aiming to enhance the understanding of digestive surgery for students, interns, and young surgeons by limiting costs. Its efficacy was assessed via questionnaires before implementation in surgical education. The VLM provides nine-minute VR views of surgeries, from both 180- and 360-degree angles. It was created with L.A.B. Co., Ltd. and incorporates surgery videos from biliary malignancy patients. Following VLM development, a survey was conducted among surgeons who had experienced it. Twenty-eight participants (32% of observers) responded to the survey. A majority (81%) reported positive experiences with the VR content and showed interest in VR video production, though some reported sickness. Most respondents were experienced surgeons, and nearly all believed VR was important for medical education with a mean score of 4.14 on a scale of up to 5. VR was preferred over 3D printed models due to its application versatility. Participants expressed the desire for future VR improvements, such as increased mobility, cloud connectivity, cost reduction, and better resolution. The VLM platform, coupled with this innovative teaching approach, offers experiential learning in intraabdominal surgery, effectively enriching the knowledge of students and surgeons ahead of surgical education and training.

Extracellular Volume Fraction Calculated Using Contrast-Enhanced Computed Tomography as a Biomarker of Oxaliplatin-Induced Sinusoidal Obstruction Syndrome: A Preliminary Histopathological Analysis.

Background: Oxaliplatin (OX)-based chemotherapy induces sinusoidal obstruction syndrome (SOS) in the nontumorous liver parenchyma, which can increase the risk of liver resection due to colorectal liver metastasis (CRLM). The extracellular volume (ECV) calculated from contrast-enhanced computed tomography (CT) has been reported to reflect the morphological change of hepatic fibrosis. The present retrospective study aimed to evaluate the ECV fraction as a predictive factor for OX-induced SOS. Methods: Our study included 26 patients who underwent liver resection for CRLM after OX-based chemotherapy with a preoperative dynamic CT of appropriate quality. We investigated the relationship between the pathological SOS grade and the ECV fraction. Results: Overall, 26 specimens from the patients were graded with the SOS classification of Rubbia-Brandt et al. as follows: grade 0, n = 17 (65.4%); grade 1, n = 4 (15.4%); and grade 2, n = 5 (19.2%). No specimens showed grade 3 SOS. In a univariate analysis, the ECV fraction in grade 0 SOS was significantly lower than that in grade 1 + 2 SOS (26.3 ± 3.4% vs. 30.6 ± 7.0%; P = 0.025). The cutoff value and AUC value of the ECV fraction to distinguish between grades 0 and 1 + 2 were 27.5% and 0.771, respectively. Conclusions: Measurement of the ECV fraction was found to be a potential noninvasive diagnostic method for determining early-stage histopathological sinusoidal injury induced by OX-based chemotherapy.

Liver hanging maneuver is suitable in major hepatectomy for liver malignancies over 5 cm.

Objectives: Hepatic transection through an anterior approach is required to successfully complete anatomical hepatectomy for large liver malignancies. The liver hanging maneuver (LHM) is an alternative procedure for transection on an adequate cut plane and may reduce intraoperative bleeding and transection times. Material and Methods: We examined the medical records of 24 patients with large liver malignancies (>5 cm) who had undergone anatomical hepatic resection with LHM (n= 9) or without LHM (n= 15) between 2015 and 2020. Patient demographics, preoperative hepatic function, surgical records, and post-hepatectomy outcomes were retrospectively compared between the LHM and non-LHM groups. Results: The prevalence of tumors >10 cm was significantly higher in the LHM group than in the non-LHM group (p <0.05). Furthermore, LHM was significantly performed to right and extended right hepatectomies in the background normal liver (p <0.05). Although transection times did not significantly differ between the two groups, the amount of intraoperative blood loss was slightly lower in the LHM group than in the non-LHM group (1.566 mL vs. 2.017 mL), and blood transfusion was not needed for patients in the LHM group. Post-hepatectomy liver failure and bile leakage were not observed in LHM. However, the length of hospitalization was slightly shorter in the LHM group than in the non-LHM group. Conclusion: LHM is useful for transecting an adequately cut plane in hepatectomy for liver tumors over 5 cm-in-size located on the right side and achieves better outcomes.