Impact of AI system on recognition for anatomical landmarks related to reducing bile duct injury during laparoscopic cholecystectomy.

BACKGROUND: According to the National Clinical Database of Japan, the incidence of bile duct injury (BDI) during laparoscopic cholecystectomy has hovered around 0.4% for the last 10 years and has not declined. On the other hand, it has been found that about 60% of BDI occurrences are due to misidentifying anatomical landmarks. However, the authors developed an artificial intelligence (AI) system that gave intraoperative data to recognize the extrahepatic bile duct (EHBD), cystic duct (CD), inferior border of liver S4 (S4), and Rouviere sulcus (RS). The purpose of this research was to evaluate how the AI system affects landmark identification. METHODS: We prepared a 20-s intraoperative video before the serosal incision of Calot's triangle dissection and created a short video with landmarks overwritten by AI. The landmarks were defined as landmark (LM)-EHBD, LM-CD, LM-RS, and LM-S4. Four beginners and four experts were recruited as subjects. After viewing a 20-s intraoperative video, subjects annotated the LM-EHBD and LM-CD. Then, a short video is shown with the AI overwriting landmark instructions; if there is a change in each perspective, the annotation is changed. The subjects answered a three-point scale questionnaire to clarify whether the AI teaching data advanced their confidence in verifying the LM-RS and LM-S4. Four external evaluation committee members investigated the clinical importance. RESULTS: In 43 of 160 (26.9%) images, the subjects transformed their annotations. Annotation changes were primarily observed in the gallbladder line of the LM-EHBD and LM-CD, and 70% of these shifts were considered safer changes. The AI-based teaching data encouraged both beginners and experts to affirm the LM-RS and LM-S4. CONCLUSION: The AI system provided significant awareness to beginners and experts and prompted them to identify anatomical landmarks linked to reducing BDI.

[Collision Tumor Involving Primary Ascending Colon Cancer and Malignant Lymphoma].

A 78-year-old male was diagnosed with a primary gastric B-cell malignant lymphoma and metastatic lung tumor 10 years ago. He underwent chemotherapy at another hospital, achieved complete remission, and was actively undergoing follow- up. He presented to our hospital with a 1-month history of a bulge in his right lower abdomen. CT revealed thickening of the ascending colon and dilatation of the oral intestine. He was diagnosed with ascending colon cancer and underwent right hemicolectomy. The subsequent pathological examination revealed a collision tumor involving diffuse, large B-cell lymphoma and well-differentiated adenocarcinoma. He was discharged from our hospital and received chemotherapy at another institution. Unfortunately, the patient died of interstitial pneumonia 31 months postoperatively. This report describes the resection of a collision tumor involving ascending colon cancer and malignant lymphoma. Surgical treatment combined with postoperative chemotherapy improved this patient's long-term survival.

[Malignant Melanoma of a Male Breast That Was Difficult to Differentiate from Breast Cancer-A Case Report].

INTRODUCTION: Malignant melanoma in the male breast is extremely rare. Here we report a case of malignant melanoma in which a small cystic lesion in the male breast gradually increased during follow-up and was difficult to distinguish from breast cancer. CASE: A 65-year-old male was diagnosed with a tumor in the right breast and was referred to our department for further examination. At 42 years of age, he underwent tumor resection of a malignant melanoma of the abdominal skin. Mammary ultrasonography showed a 0.6 cm cystic mass in his right breast. Eight months later, the right breast mass had increased to 1.4 cm, and a core needle biopsy suggested breast cancer. Total mastectomy with axillary lymph node dissection was performed. HE staining of the resected tumor showed intranuclear inclusion bodies and some large nucleoli. On the basis of various immunostaining methods, malignant melanoma was diagnosed instead of breast cancer. After surgery, adjuvant chemotherapy with molecularly targeted drugs was administered. DISCUSSION: This might have been a case of male breast metastasis of malignant melanoma with very late recurrence.

[Laparoscopic Tumor Resection for Asymptomatic Paraganglioma-A Case Study].

A 55-year-old man was referred for the close examination of an abdominal mass noted on abdominal ultrasonography during a physical examination. A contrast-enhanced computed tomography(CT)scan of his abdomen revealed a 36-mm heterogeneously contrast-enhanced mass on the left side of the aorta. He was referred for laparoscopic tumor resection without preoperative histological examination. The tumor was identified from the dorsal aspect of the mesentery of the transverse colon and was resected only because it was detachable from the duodenum. A temporary abnormal hypertension was observed intraoperatively. However, he exhibited a favorable postoperative course and was discharged on the 8th postoperative day. Grossly, it was a nodular tumor with a diameter of 38 mm. Histopathological examination revealed that the tumor cells having abundant cytoplasm formed large foci and were surrounded by sinusoidal vessels. Immunohistochemistry results were positive for chromogranin A, synaptophysin, and neural cell adhesion molecule; thus, paraganglioma was diagnosed. Herein, we report a case of laparoscopic resection of an asymptomatic paraganglioma.

Impact of postoperative remote infection on length of stay and medical costs in hospitals in Japan.

PURPOSE: To analyze the impact of postoperative remote infections (PRIs) on medical expenditure. METHODS: The subjects of this retrospective study were 338 patients who had undergone gastroenterological surgery at one of the 20 Japanese institutions within the Japan Society for Surgical Infection (JSSI) and mainly authorized as educational institutions. The patients were allocated to 169 pairs of those with a PRI (PRI (+) group) matched with those without a PRI (PRI (-) group). PRIs included pneumonia, urinary tract infection (UTI), catheter-associated blood stream infection (CA-BSI), and antibiotic-associated enteritis. RESULTS: SSI developed in 74 of the 338 patients (22 without PRI and 52 with PRI). The SSI incidence was significantly higher in the PRI (+) group (p < 0.001). The difference in the median postoperative length of hospital stay was 15 days, indicating a significant prolongation in the PRI (+) group (p < 0.001). The PRI (+) group also had a higher rate of inter-hospital transfer (p < 0.01) and mortality (p < 0.001). Similarly, the difference in median postoperative medical fees was $6832.3, representing a significant increase in the PRI (+) group (p < 0.001). CONCLUSIONS: The postoperative length of hospital stay is longer and the postoperative medical expenditure is higher for patients with a PRI than for those without a PRI.

Quick detection of causative bacteria in cases of acute cholangitis and cholecystitis using a multichannel gene autoanalyzer.

PURPOSES: Acute cholangitis and cholecystitis can become severe conditions as a result of inappropriate therapeutic administration and thereafter become increasingly resistant to antimicrobial treatment. The simultaneous detection of the bacterial nucleic acid and antimicrobial resistance gene is covered by the national health insurance program in Japan for sepsis. In this study, we evaluate the use of a multichannel gene autoanalyzer (Verigene system) for the quick detection of causative bacteria in cases of acute cholangitis and cholecystitis. METHODS: This study included 108 patients diagnosed with acute cholangitis or cholecystitis between June 2015 and November 2018. A bacterial culture test and Verigene assay were used to evaluate the bile samples. RESULTS: The most commonly isolated bacteria were Escherichia coli, which includes six extended-spectrum beta-lactamase (ESBL)-producing E. coli. Among the patients with positive bile cultures, bacteria were detected in 35.7% of cases via the Verigene system. The detection rates of the Verigene system significantly increased when the number of bacterial colonies was ≥ 106 colony-forming unit (CFU)/mL (58.1%). Cases with a maximum colony quantity of ≥ 106 CFU/mL exhibited higher inflammation, suggesting the presence of a bacterial infection. CONCLUSIONS: The Verigene system might be a new method for the quick detection of causative bacteria in patients with infectious acute cholangitis and cholecystitis.

Successful perioperative infection control measures after gastroenterological surgery reduced the number of cases of methicillin-resistant Staphylococcus aureus or Clostridioides (Clostridium) difficile infection to almost zero over a 30-year period: a single-department experience.

PURPOSE: To investigate changes in the incidence of postoperative infections in the surgical department of a teaching hospital. METHODS: During the 30-year period from September 1987 to August 2017, 11,568 gastroenterological surgical procedures were performed in our surgical department. This 30-year period was divided into seven periods (A-G), ranging from 2 to 7 years each and based on the infection control methods used in each period. We then compared the rates of incisional surgical site infection (SSI) and organ/space SSI; remote infection (RI) including respiratory tract infection (RTI), intravascular catheter-related infection, and urinary tract infection (UTI); and antibiotic-associated colitis caused by methicillin-resistant Staphylococcus aureus (MRSA) enteritis or Clostridioides (Clostridium) difficile-associated disease (CDAD) among the seven periods. RESULTS: In periods B (September 1990-August 1997) and E (November 2004-July 2007), when a unique antibiotic therapy devised in our department was in use, MRSA was isolated from only 0.3% and 0.4% of surgical patients, respectively, and these rates were significantly lower than those in the other periods (p < 0.05). The rate of CDAD increased during period F (August 2007-July 2014), but in period G (August 2014-August 2017), restrictions were placed on the use of antibiotics with a strong anti-anaerobic action and, in this period, the rate of CDAD was only 0.04%, which was significantly lower than that in period F (p < 0.05). CONCLUSIONS: Limiting the use of antibiotics that tend to disrupt the intestinal flora may reduce the rates of MRSA infection and CDAD after gastroenterological surgery.

Neutrophil/lymphocyte ratio has a prognostic value for patients with terminal cancer.

BACKGROUND: Determining prognosis in advanced cancer is of key importance. Various prognostic scores have been developed. However, they are often very complex. In this study, we evaluated the feasibility of neutrophil/lymphocyte ratio (NLR) as an index to estimate survival in terminal cancer patients. METHODS: NLR was calculated retrospectively based on blood tests performed at 3 months, 2 months, 4 weeks, 3 weeks, 2 weeks, 1 week, and within 3 days before death in 160 cancer patients (82 men, 78 women; age range, 33-99 years; mean age, 69.8 years). RESULTS: NLR increased significantly with time (P < 0.0001). Mean NLR was significantly higher in patients who died within 4 weeks (29.82) than in those who lived more than 4 weeks (6.15). The NLR cutoff point was set at 9.21 according to receiver operating characteristic curve analysis (area under the curve, 0.82; 95% confidence interval, 0.79-0.85). We inferred that life expectancy would be <4 weeks when NLR >9.21. The sensitivity, specificity, positive predictive value, and negative predictive value were 65.6, 84.1, 90.6, and 51.1%, respectively. The positive and negative likelihood ratios were 4.125 and 0.409, respectively. CONCLUSIONS: NLR appears to be a useful and simple parameter to predict the clinical outcomes of patients with terminal cancer.

Open surgery versus laparoscopic surgery after stent insertion for obstructive colorectal cancer.

PURPOSE: To compare the outcomes of laparoscopic surgery vs. open surgery after insertion of a colonic stent for obstructive colorectal cancer. METHODS: Between April 2005 and August 2013, 58 patients underwent surgery after the insertion of a colonic stent for obstructive colorectal cancer. We analyzed the outcomes of the patients who underwent laparoscopic surgery vs. those who underwent open surgery. RESULTS: We compared blood loss, operative time, hospital stay, and complications in 26 patients who underwent laparoscopic surgery and 32 patients who underwent open surgery. Blood loss was significantly less in the laparoscopic surgery group, but operative time was significantly shorter in the open surgery group. The length of hospital stay was shorter in the laparoscopic surgery group than in the open surgery group, but the difference was not significant. There was no significant difference in postoperative surgical complications between the groups. CONCLUSION: The patients who underwent laparoscopic resection had less blood loss, although no significant difference was found in postoperative morbidity or mortality. Thus, laparoscopic resection after stent insertion is a feasible and safe option for patients with obstructive colorectal cancer.

Successful treatment of a common hepatic artery pseudoaneurysm using a coronary covered stent following pancreatoduodenectomy: report of a case.

This report presents the case of a common hepatic artery (CHA) pseudoaneurysm secondary to postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD), which was successfully treated using a coronary covered stent. A 70-year-old female underwent subtotal stomach-preserving PD for middle cholangiocarcinoma. POPF was identified on postoperative day (POD) 7, and the patient suddenly lost 500 ml of blood via the abdominal drain on POD 19. Urgent celiac arteriography revealed a CHA pseudoaneurysm. A coronary covered stent was placed to prevent rupture of the pseudoaneurysm and to maintain hepatic arterial flow, instead of performing transarterial embolization. No vascular adverse events were encountered during or after the procedure. Computed tomography and angiography showed a patent stent graft and good hepatic arterial flow 9 months after placement of the stent. Endovascular stent-graft placement not only treated the pseudoaneurysm, but also preserved the arterial blood flow. This report describes the placement of a covered stent graft for delayed hemorrhage after PD.

Risk factors for conversion of laparoscopic cholecystectomy to open surgery associated with the severity characteristics according to the Tokyo guidelines.

PURPOSE: The aim of this retrospective study was to identify the risk factors associated with the severity characteristics in the Tokyo guidelines for conversion to open surgery in patients with acute cholecystitis (AC) who underwent laparoscopic cholecystectomy. METHODS: A total of 225 patients were enrolled in the study. The patients were classified into two groups: a conversion group and a no-conversion group. The preoperative characteristics and therapeutic strategy were analyzed as risk factors for conversion to open surgery. The postoperative outcomes were also analyzed. RESULTS: Conversion to open surgery occurred in 29 patients (12.9%), including seven patients (6.7%) with mild AC and 22 patients (18.5%) with moderate AC. A univariate analysis showed that the risk factors for conversion to open surgery included a duration of symptoms longer than 72 h, an elevated C-reactive protein (CRP) value and the Tokyo guidelines 2013 (TG 13) severity classification. The multivariate analysis showed that the risk factors for conversion to open surgery included a duration of symptoms longer than 72 h and a CRP value >11.5 mg/dl. CONCLUSIONS: A duration of symptoms longer than 72 h, which is included in the criterion for moderate AC severity in the TG 13, was an independent risk factor for conversion to open surgery. In addition, adoption of a high CRP value as an additional criterion for moderate AC may increase the utility of the TG 13.

Two cases of laparoscopic deroofing of giant liver cysts using indocyanine green fluorescence imaging.

Laparoscopic deroofing (LD) for giant liver cysts using indocyanine green (ICG) fluorescence imaging was performed in two patients: a 53-year-old man with a 26-cm, symptomatic cyst and a 50-year-old woman with a 13-cm, symptomatic cyst. ICG fluorescence imaging can be used to easily identify the boundary between the liver parenchyma and the liver cyst. No postoperative bile leakage was observed in both patients. ICG fluorescence imaging is expected to become a desirable procedure in LD for giant liver cysts to reduce the occurrence of perioperative complications.

Validation of a surgical difficulty grading system in laparoscopic cholecystectomy for acute cholecystitis.

BACKGROUND: The surgical difficulty of laparoscopic cholecystectomy (LC) for acute cholecystitis varies from case to case, and appropriate intraoperative evaluation would help prevent bile duct injury (BDI). METHODS: We analyzed 178 patients who underwent LC for acute cholecystitis. Expert surgeons and trainees individually evaluated the surgical difficulty. The inter-rater agreement was analyzed using Conger's κ and Gwet's agreement coefficient (AC). Furthermore, we analyzed the predictive surgical difficulty item for performing subtotal cholecystectomy (STC). RESULTS: Regarding the inter-rater agreement between expert surgeons and trainees, 15 of the 17 surgical difficulty items had a Gwet's AC of 0.5 or higher, indicating "moderate" agreement or higher. Furthermore, the highest and total surgical difficulty scores were deemed "substantial" agreement. Scarring and dense fibrotic changes around the Calot's triangle area with easy bleeding with/without necrotic changes were predictive of whether STC should be performed. CONCLUSIONS: This surgical difficulty grading system is expected to be a tool that can be used by any surgeon with LC experience. STC should be performed to prevent BDI according to the changes around the Calot's triangle area.

A multi-institutional study designed by members of Tokyo Guidelines (TG) Core Meeting to elucidate the clinical characteristics and pathogenesis of acute cholangitis after bilioenteric anastomosis and biliary stent insertion with a focus on biliary obstruction: Role of transient hepatic attenuation difference (THAD) and pneumobilia in improving TG diagnostic performance.

BACKGROUND/PURPOSE: The aim of this study was to clarify the clinical characteristics of acute cholangitis (AC) after bilioenteric anastomosis and stent-related AC in a multi-institutional retrospective study, and validate the TG18 diagnostic performance for various type of cholangitis. METHODS: We retrospectively reviewed 1079 AC patients during 2020, at 16 Tokyo Guidelines 18 (TG 18) Core Meeting institutions. Of these, the post-biliary reconstruction associated AC (PBR-AC), stent-associated AC (S-AC) and common AC (C-AC) were 228, 307, and 544, respectively. The characteristics of each AC were compared, and the TG18 diagnostic performance of each was evaluated. RESULTS: The PBR-AC group showed significantly milder biliary stasis compared to the C-AC group. Using TG18 criteria, definitive diagnosis rate in the PBR-AC group was significantly lower than that in the C-AC group (59.6% vs. 79.6%, p < .001) because of significantly lower prevalence of TG 18 imaging findings and milder bile stasis. In the S-AC group, the bile stasis was also milder, but definitive-diagnostic rate was significantly higher (95.1%) compared to the C-AC group. The incidence of transient hepatic attenuation difference (THAD) and pneumobilia were more frequent in PBR-AC than that in C-AC. The definitive-diagnostic rate of PBR-AC (59.6%-78.1%) and total cohort (79.6%-85.3%) were significantly improved when newly adding these items to TG18 diagnostic imaging findings. CONCLUSIONS: The diagnostic rate of PBR-AC using TG18 is low, but adding THAD and pneumobilia to TG imaging criteria may improve TG diagnostic performance.

Rapid identification of bacteria using a multiplex polymerase chain reaction system for acute abdominal infections.

Purpose: Acute abdominal infections can be fatal if the causative organism (s) are misidentified. The spread of antimicrobial-resistant bacteria has become a serious problem worldwide, making antibiotic selection extremely difficult. Using quantitative metagenomic analysis, we evaluated a commercial multiplex polymerase chain reaction (PCR) system (FilmArray™, bioMérieux, Marcy-l'Étoile, France) for the rapid identification of causative bacteria. Methods: The cases of 10 patients with acute abdominal infections were enrolled in this retrospective study. There were six cases of perforated peritonitis and four cases of intraabdominal abscess. Fluid collected from the acute surgical abdominal infections were examined. Results: All specimens tested positive for microorganisms in culture, and six involved two or more microorganisms. Using the multiplex PCR system, nine of ten specimens were found to involve at least one microorganism. One specimen was not included in the multiplex PCR system panel. Nineteen of 21 microorganisms (90.5%) isolated by culture were detected by the multiplex PCR system. Microorganisms with very small numbers of reads (19 reads) were detectable. Conclusion: This multiplex PCR system showed a high detection rate for causative microorganisms in ascites and intraabdominal abscesses. This system may be suitable as an affordable rapid identification system for causative bacteria in these cases.

Modified Socratic Method (planned and executed by Takada) for medical education: Grade II Acute Cholecystitis of Tokyo Guidelines 2018 as an example case.

BACKGROUND: Socratic method, which is an educational method to promote critical thinking through a dialogue, has never been practiced in a large number of people at the academic societies. METHODS: Modified Socratic method was performed for the first time as an educational seminar using an example case of moderate acute cholecystitis based on the evidence described in Tokyo Guidelines 2018. We adopted a method that Takada had been modifying for many years: the instructor first knows the degree of recognition of the audience, then the instructor gives a lecture in an easy-to-understand manner and receives questions from the audience, followed by repeated questions and answers toward a common recognition. RESULTS: Using slides, video, and an answer pad, 281 participants including the audience, instructors and moderators came together to repeatedly ask and answer questions in the five sessions related to the case scenario. The recognition rate of the topic of Critical View of Safety increased significantly before vs after this method (53.0% vs 90.3%). The seminar had been successfully performed by receiving a lot of praise from the participants. CONCLUSION: This educational method is considered to be adopted by many academic societies in the future as an effective educational method.

Application of a novel surgical difficulty grading system during laparoscopic cholecystectomy.

BACKGROUND: Prevention of bile duct injury and vasculo-biliary injury while performing laparoscopic cholecystectomy (LC) is an unsolved problem. Clarifying the surgical difficulty using intraoperative findings can greatly contribute to the pursuit of best practices for acute cholecystitis. In this study, multiple evaluators assessed surgical difficulty items in unedited videos and then constructed a proposed surgical difficulty grading. METHODS: We previously assembled a library of typical video clips of the intraoperative findings for all LC surgical difficulty items in acute cholecystitis. Fifty-one experts on LC assessed unedited surgical videos. Inter-rater agreement was assessed by Fleiss's κ and Gwet's agreement coefficient (AC). RESULTS: Except for one item ("edematous change"), κ or AC exceeded 0.5, so the typical videos were judged to be applicable. The conceivable surgical difficulty gradings were analyzed. According to the assessment of difficulty factors, we created a surgical difficulty grading system (agreement probability = 0.923, κ = 0.712, 90% CI: 0.587-0.837; AC2  = 0.870, 90% CI: 0.768-0.972). CONCLUSION: The previously published video clip library and our novel surgical difficulty grading system should serve as a universal objective tool to assess surgical difficulty in LC.

Antibiotic time-lag combination therapy with fosfomycin for postoperative intra-abdominal abscesses.

The first-line treatment for intra-abdominal abscess is source control. Sometimes, however, source control is too invasive for relatively small abscesses and is not feasible due to the risk of injury to some organs. Based on reports that fosfomycin (FOM) can break up biofilms to enhance the permeability of other antibiotics, we investigated the FOM time-lag combination therapy (FOM-TLCT). We enrolled 114 patients who had intra-abdominal abscess after gastrointestinal surgery and examined the efficacy of FOM-TLCT using the same therapeutic antibiotic (TA) as that which had been used previously, but had proven ineffective, at the same dose schedule. The efficacy endpoint determination was carried out as follows: among the systemic inflammatory response syndrome (SIRS)-positive cases, even after administration of TA, excellent outcome was defined as SIRS negative within 7 days of FOM-TLCT with TA without the need for other treatment, including other antibiotics or drainage. Of the 114 patients enrolled, 104 cases (SIRS positive 73; SIRS negative 31) were assessed. Ten patients were excluded; four had received TA at higher doses, three had received different TAs, and three were considered to have bacteria resistant to TAs. Among these patients, 86.3% (63/73) of the SIRS-positive cases were classified as excellent, and 90.3% (28/31) of the SIRS-negative cases were classified as effective. In total, the efficacy rate was 87.5% (91/104). The total no-response rates were 12.5% (13/104). FOM-TLCT seems to be effective for treating refractory intra-abdominal abscess.