Distribution of Splenic Arterial Flow and Segmental Spleen Volume for Partial Splenic Arterial Embolization.

INTRODUCTION: The spleen is a lymphatic organ that manages immune surveillance of the blood, produces blood cells, and helps filter the blood, remove old blood cells, and fight infection. The normal splenic weight is approximately 65-265 g. This study evaluated spleen volume and segmental volume. METHODS: 121 patients who underwent enhanced CT at our center were analyzed. The spleen was divided into upper, middle, and lower segments according to arterial flow area, and the volume of each segment was measured. Patients were classified into two groups as those with and without liver cirrhosis, and differences in the distribution of the segments in these groups was evaluated. RESULTS: The mean upper, middle, and lower spleen segmental volume ratios were 35.4%, 37.0%, and 27.6%, respectively. In the liver cirrhosis group, the segmental splenic volume ratios for the upper, middle, and lower segments were 34.5%, 38.5%, and 28.0%, respectively, indicating that these ratios remain similar regardless of liver cirrhosis status. CONCLUSION: The present findings on segmental spleen volume are useful for estimating infarction volume in cases of partial splenic arterial embolization.

Stenting of Inferior Right Hepatic Vein in a Patient with Budd-Chiari Syndrome: A Case Report.

A Japanese man in his 20s was referred to our hospital with a two-month history of abdominal fullness and leg edema. Abdominal computed tomography revealing massive ascites and ostial blockage of the main hepatic veins, and angiographic evaluation demonstrating obstruction of the main hepatic veins yielded a diagnosis of Budd-Chiari syndrome (BCS). Diuretic agents were prescribed for the ascites but failed to provide relief. The patient was referred to our department for further evaluation and treatment. Angiography showed ostial obstruction of the main hepatic veins, with most of the portal hepatic flow draining from an inferior right hepatic vein (IRHV) into the inferior vena cava (IVC) thorough an intrahepatic portal venous and venovenous shunt. Access between the main hepatic veins and IVC was impossible, but cannulation between the IRHV and IVC was achieved. Because of the venovenous connection between the main hepatic vein and the IRHV, metallic stents were placed into two IRHVs to decrease congestion in the hepatic venous outflow. After stent placement followed by balloon expansion, the gradient pressure between the hepatic vein and IVC improved remarkably. The ascites and lower leg edema improved postoperatively, and long-term stent patency (6 years) was achieved.

Evaluation of splenic infarction ratio and platelet increase ratio after partial splenic artery embolization.

OBJECTIVE: The spleen is part of the lymphatic system and is one of the least understood organs of the human body. It is involved in the production of blood cells and helps filter the blood, remove old blood cells, and fight infection. Partial splenic artery embolization (PSE) is widely used to treat pancytopenia and portal hypertension. The efficacy of PSE for improving thrombocytopenia has been well demonstrated. In this study, we evaluated the splenic infarction ratio and platelet increase ratio after PSE. METHODS: Forty-five consecutive patients underwent PSE from January 2014 to August 2022. We retrospectively evaluated the splenic infarction volume and ratio after PSE and analyzed the relationship between the splenic infarction ratio and platelet increase ratio after PSE. RESULTS: The platelet increase ratio was correlated with the splenic infarction ratio after PSE. The cutoff value for the splenic infarction ratio with a two-fold platelet increase was 63.0%. CONCLUSION: We suggest performance of PSE in patients with a splenic infarction ratio of 63% to double the expected platelet count.

The Role of the Spleen in Portal Hypertension.

As liver disease progresses, intrahepatic vascular resistance increases (backward flow theory of portal hypertension) and collateral veins develop. Adequate portal hypertension is required to maintain portal flow into the liver through an increase in blood flow into the portal venous system (forward flow theory of portal hypertension). The splenic artery resistance index is significantly and selectively elevated in cirrhotic patients. In portal hypertension, a local hyperdynamic state occurs around the spleen. Splenomegaly is associated with a poor prognosis in cirrhosis and is caused by spleen congestion and by enlargement and hyperactivation of splenic lymphoid tissue. Hypersplenism can lead to thrombocytopenia caused by increased sequestering and breakdown of platelets in the spleen. The close relationship between the spleen and liver is reflected in the concept of the hepatosplenic axis. The spleen is a regulatory organ that maintains portal flow into the liver and is the key organ in the forward flow theory of portal hypertension. This review summarizes the literature on the role of the spleen in portal hypertension.

Management of Simple Hepatic Cyst.

Simple hepatic cysts are typically saccular, thin-walled masses with fluid-filled epithelial lined cavities. They arise from aberrant bile duct cells that develop during embryonic development. With the development of diagnostic modalities such as ultrasonography (US), CT, and MRI, simple hepatic cysts are frequently detected in clinical examinations. US is the most useful and noninvasive tool for diagnosis of simple hepatic cysts and can usually differentiate simple hepatic cysts from abscesses, hemangiomas, and malignancies. Cysts with irregular walls, septations, calcifications, or daughter cysts on US should be evaluated with enhanced CT or MRI, to differentiate simple hepatic cysts from cystic neoplasms or hydatid cysts. Growth and compression of hepatic cysts cause abdominal discomfort, pain, distension, and dietary symptoms such as nausea, vomiting, a feeling of fullness, and early satiety. Complications of simple hepatic cysts include infection, spontaneous hemorrhage, rupture, and external compression of biliary tree or major vessels. Asymptomatic simple hepatic cysts do not require treatment. Treatment for symptomatic simple hepatic cysts includes percutaneous aspiration, aspiration followed by sclerotherapy, and surgery. The American College of Gastroenterology clinical guidelines recommend laparoscopic fenestration because of its high success rate and low invasiveness. Percutaneous procedures for treatment of simple hepatic cysts are particularly effective for immediate palliation of patient symptoms; however, they are not generally recommended because of the high rate of recurrence. Management of simple hepatic cysts requires correct differentiation from neoplasms and infections, and selection of a reliable treatment.

Massage of the Hepatoduodenal Ligament Recovers Portal Vein Flow Immediately After the Pringle Maneuver in Hepatectomy.

BACKGROUND: The Pringle maneuver is often used in liver surgery to minimize bleeding during liver transection. Many authors have demonstrated that intermittent use of the Pringle maneuver is safe and effective when performed appropriately. However, some studies have reported that the Pringle maneuver is a significant risk factor for portal vein thrombosis. In this study, we evaluated the effectiveness of portal vein flow after the Pringle maneuver and the impact that massaging the hepatoduodenal ligament after the Pringle maneuver has on portal vein flow. MATERIALS AND METHODS: Patients treated with the Pringle maneuver for hepatectomies performed to treat hepatic disease at our hospital between August 2014 and March 2019 were included in the study (N = 101). We divided these patients into two groups, a massage group and nonmassage group. We measured portal vein blood flow with ultrasonography before and after clamping of the hepatoduodenal ligament. We also evaluated laboratory data after the hepatectomy. RESULTS: Portal vein flow was significantly lower after the Pringle maneuver than before clamping of the hepatoduodenal ligament. The portal vein flow after the Pringle maneuver was improved following massage of the hepatoduodenal ligament. After hepatectomy, serum prothrombin time was significantly higher and serum C-reactive protein was significantly lower in the massage group than in the nonmassage group. CONCLUSION: Massaging the hepatoduodenal ligament after the Pringle maneuver is recommended in order to quickly recover portal vein flow during hepatectomy and to improve coagulability.

Current Status of Laparoscopic Hepatectomy.

Before the first laparoscopic hepatectomy (LH) was described in 1991, open hepatectomy (OH) was the only choice for surgical treatment of liver tumors. LH indications were initially based solely on tumor location, size, and type. Use of LH has spread rapidly worldwide because it reduces incision size. This review systematically assesses the current status of LH. As compared with OH, LH is significantly less complicated, requires shorter hospital stays, and results in less blood loss. The long-term survival rates of LH and OH are comparable. Development of new techniques and instruments will improve the conversion rate and reduce complications. Furthermore, development of surgical navigation will improve LH safety and efficacy. Laparoscopic major hepatectomy for HCC remains a challenging procedure and should only be performed by experienced surgeons. In the near future, a training system for young surgeons will become mandatory for standardization of LH, and LH will likely become better standardized and have broader applications.

Evaluation of positive ductal margins of biliary tract cancer in intraoperative histological examination.

At present the only method available to confirm microscopic infiltration of cancer into ductal margins during surgery, is intraoperative histological examination. In the present study, the status of the surgical margins and postoperative course were evaluated to determine any correlation between remnant carcinoma and postoperative survival. All consecutive patients who underwent resection for biliary tract cancer between January 2004 and May 2012 were identified from a database. Positive margin cases were divided into two groups, invasive carcinoma and carcinoma in situ (CIS). Immunohistochemical staining targeting Ki67 and p53 for positive margins was performed. Cases of major vessel invasion were significantly increased in the positive group compared with the negative group. The recurrence rate was significantly lower in the CIS group compared with the invasive group. The survival rate was significantly increased in the CIS group compared with the invasive group. The expression levels of p53 and Ki67 were significantly increased in the invasive group compared with the CIS group. No statistical correlations were observed between the expression of p53 or Ki67 and the survival or recurrence of disease. In the positive group, resected margin status was the principal factor associated with recurrence-free survival according to Cox-regression analysis. In conclusion, the status of the resected margins in the positive group was the most important factor for postoperative survival and recurrence in cholangiocarcinoma, not immunohistochemical staining targeting Ki67 and p53.

Evaluation of the Impact of Preoperative Values of Hyaluronic Acid and Type IV Collagen on the Outcome of Patients with Hepatocellular Carcinoma After Hepatectomy.

BACKGROUND: Recently, some reports have revealed a relationship between post-hepatectomy prognosis in hepatocellular carcinoma (HCC) and hepatic fibrosis markers. We evaluated the relationship between these markers of hepatic fibrosis, clinicopathological findings, and prognosis. METHODS: Three hundred and sixty patients underwent hepatectomy for HCC in the Nippon Medical School Hospital between 1993 and 2013. We divided these patients into two groups: normal serum hyaluronic acid (HA) levels and abnormal levels. We also divided patients into groups with normal serum type IV collagen levels and abnormal levels. RESULTS: The overall survival rate and recurrence-free survival rate of the normal group were significantly higher than those of the abnormal group. In the normal hyaluronic acid group, serum albumin and prothrombin time were significantly higher than in the abnormal group, and age, hepatitis C virus antibody (HCV)-Ab positivity, Child-Pugh grade B, liver cirrhosis, indocyanine green retention rate at 15 min (ICGR15), type IV collagen level, and type IV collagen 7s level were significantly lower than those in the abnormal group. In the normal type IV collagen group, HCV-Ab positivity, liver cirrhosis, ICGR15, HA level, and type IV collagen 7s level were significantly lower than those in the abnormal group, and the serum albumin level was significantly higher than that in the abnormal group. Multivariate analysis independently revealed the significant effect of serum type IV collagen on the overall survival rate as well as the significant effect of serum HA on the recurrence-free survival rate in patients who underwent hepatectomy for HCC. CONCLUSIONS: Preoperative examinations of serum hyaluronic acid levels and type IV collagen levels are imperative for hepatic resection for HCC because these markers are significantly associated with liver function and prognosis.

Characteristics predicting laparoscopic skill in medical students: nine years' experience in a single center.

INTRODUCTION: We introduced laparoscopic simulator training for medical students in 2007. This study was designed to identify factors that predict the laparoscopic skill of medical students, to identify intergenerational differences in abilities, and to estimate the variability of results in each training group. Our ultimate goal was to determine the optimal educational program for teaching laparoscopic surgery to medical students. METHODS: Between 2007 and 2015, a total of 270 fifth-year medical students were enrolled in this observational study. Before training, the participants were asked questions about their interest in laparoscopic surgery, experience with playing video games, confidence about driving, and manual dexterity. After the training, aspects of their competence (execution time, instrument path length, and economy of instrument movement) were assessed. RESULTS: Multiple regression analysis identified significant effects of manual dexterity, gender, and confidence about driving on the results of the training. The training results have significantly improved over recent years. The variability among the results in each training group was relatively small. CONCLUSIONS: We identified the characteristics of medical students with excellent laparoscopic skills. We observed educational benefits from interactions between medical students within each training group. Our study suggests that selection and grouping are important to the success of modern programs designed to train medical students in laparoscopic surgery.

Successful treatment of limy bile syndrome extending to the common bile duct by laparoscopic cholecystectomy and common bile duct exploration: A case report and literature review.

Limy bile syndrome extending to the common bile duct (CBD) is a rare condition that lacks a standardized treatment. Laparoscopic cholecystectomy with laparoscopic choledocholithotomy by CBD exploration is preferred because it preserves the function of the sphincter of the Vater's papilla and allows treatment of both lesions. A 37-year-old man who was receiving entecavir for chronic hepatitis B developed right upper quadrant pain. Abdominal ultrasonography revealed a calcified shadow in the gallbladder and CBD. Abdominal imaging revealed a liquid-like material identified by a calcified shadow in two phases separated by a fluid-fluid level. Abdominal and 3-D drip infusion cholangiography CT showed stones in the gallbladder and CBD with limy bile. The patient underwent laparoscopic cholecystectomy and choledocholithotomy. Intraoperatively, white-yellow-colored bile and stones were drained from the CBD. A C-tube was placed. Postoperatively, remnant stones and radiopaque materials were absent. The stones comprised of >95% calcium carbonate.

Cecal Volvulus Following Elective Laparoscopic Cholecystectomy: A Case Report.

Cecal volvulus is characterized by torsion of the cecum around its own mesentery. However, cecal volvulus rarely develops soon after elective laparoscopic cholecystectomy. We report on a case of cecal volvulus that developed in a 54-year-old women 1 day after elective laparoscopic cholecystectomy and was successfully treated via colonoscopic decompression. The symptoms gradually improved in conjunction with recovery from postoperative ileus. Whether the incidence of volvulus has increased with the use of laparoscopic procedures, including laparoscopic cholecystectomy, has yet to be determined. Considering the current trend toward minimally invasive surgery, cecal volvulus should be considered in patients who have postoperative abdominal pain and distention.

Spontaneous ruptured hepatocellular carcinoma.

The incidence of hepatocellular carcinoma (HCC) is rising worldwide. Spontaneous rupture of HCC occasionally occurs, and ruptured HCC with intraperitoneal hemorrhage is potentially life-threatening. The most common symptom of ruptured HCC is acute abdominal pain. The tumor size in ruptured HCC is significantly greater than that in non-ruptured HCC, and HCC protrudes beyond the original liver margin. In the acute phase, hemostasis is the primary concern and tumor treatment is secondary. Transcatheter arterial embolization (TAE) can effectively induce hemostasis. The hemostatic success rate of TAE ranges 53-100%. A one-stage surgical operation is a treatment modality for selected patients. Conservative treatment is usually given to patients in a moribund state with inoperable tumors and thus has poor outcomes. Patients with severe ruptures of advanced HCC and poor liver function have high mortality rates. Liver failure occurs in 12-42% of patients during the acute phase. In the stable phase, tumor treatment, such as transarterial chemoembolization or hepatic resection should be concerned. The combination of acute hemorrhage and cancer in patients with ruptured HCC requires a two-step therapeutic approach. TAE followed by elective hepatectomy is considered an effective strategy for patients with ruptured HCC.

Intraperitoneal Migration of a Mesh Plug from a Hernioplasty Forming a Colocutaneous Fistula with the Cecum: Report of a Case.

Tension-free hernia repair with a mesh plug causes relatively low postoperative pain and allows an earlier return to work, as well as a low recurrence rate. Occasionally, however, hernioplasty can result in complications including mesh migration and invasion of intra-abdominal organs. This report describes the case of a 57-year-old man who had undergone a right inguinal hernioplasty 13 years previously. Recovery was uneventful until he experienced inflammation of the groin, and required open drainage three times for a refractory abscess in his right groin. Additional colonoscopy and x-ray examinations with contrast medium clearly demonstrated a mesh plug that had migrated and penetrated the cecum, forming a colocutaneous fistula. The mesh was successfully removed under general anesthesia, and the inflammation in the groin resolved.

Laparoscopic skill improvement after virtual reality simulator training in medical students as assessed by augmented reality simulator.

INTRODUCTION: Definitive assessment of laparoscopic skill improvement after virtual reality simulator training is best obtained during an actual operation. However, this is impossible in medical students. Therefore, we developed an alternative assessment technique using an augmented reality simulator. METHODS: Nineteen medical students completed a 6-week training program using a virtual reality simulator (LapSim). The pretest and post-test were performed using an object-positioning module and cholecystectomy on an augmented reality simulator(ProMIS). The mean performance measures between pre- and post-training on the LapSim were compared with a paired t-test. RESULTS: In the object-positioning module, the execution time of the task (P < 0.001), left and right instrument path length (P = 0.001), and left and right instrument economy of movement (P < 0.001) were significantly shorter after than before the LapSim training. With respect to improvement in laparoscopic cholecystectomy using a gallbladder model, the execution time to identify, clip, and cut the cystic duct and cystic artery as well as the execution time to dissect the gallbladder away from the liver bed were both significantly shorter after than before the LapSim training (P = 0.01). CONCLUSIONS: Our training curriculum using a virtual reality simulator improved the operative skills of medical students as objectively evaluated by assessment using an augmented reality simulator instead of an actual operation. We hope that these findings help to establish an effective training program for medical students.

Risk factors for bleeding esophagogastric varices.

Bleeding from gastric varices (GVs) is generally considered more severe than that from esophageal varices (EVs) but occurs less frequently. We review the risk factors for bleeding EVs and GVs. GVs were divided into 2 groups: cardiac varices (CVs, Lg-c) and fundal varices (FVs), i.e., varices involving the fundus alone (Lg-f) or varices involving both the cardia and fundus (Lg-cf). Elevated pressure in the portal vein is a risk factor for bleeding EVs. The portal pressure in patients with GVs and a gastrorenal shunt is lower than that in patients with EVs. The large size of varices is a risk factor for bleeding EVs. Red color signs are elevated red areas that are important for predicting the risk of variceal bleeding, and red wale markings, dilated venules oriented longitudinally on the mucosal surface, have been considered to be the sign with the highest risk. Red color signs are rare in FVs, possibly because of the pronounced thickness of the mucosal layer. Bleeding EVs are not associated with use of antiulcer drugs or nonsteroidal anti-inflammatory drugs (NSAIDs). Although, in patients with bleeding GVs, "occasional" use of an oral NSAID is an important step leading to variceal hemorrhage, especially from FVs, even if the mucosa is protected by antiulcer drugs. Constipation, vomiting, severe coughing, and excessive consumption of alcohol may precipitate rupture of EVs.

Surgical resection of a leiomyosarcoma of the inferior vena cava mimicking hepatic tumor.

Introduction. Leiomyosarcomas of vascular origin are particularly rare tumors occurring mainly in the inferior vena cava (IVC). They are malignant, slow-growing tumors with a poor prognosis. This paper reports on a rare case of surgical resection of an IVC leiomyosarcoma mimicking a hepatic tumor. Case Presentation. A 65-year-old Japanese male was admitted for evaluation of an abdominal tumor. Enhanced computed tomography of the abdomen revealed a slightly enhanced heterogeneous tumor, 18 mm in diameter, between the Spiegel lobe of the liver and the IVC in early-phase images, with no enhancement or washout in late-phase images. We diagnosed this tumor as either a hepatic tumor in the Spiegel lobe or a retroperitoneal tumor such as leiomyosarcoma or liposarcoma and performed a laparotomy. On the basis of surgical findings, we extirpated the tumor by performing a wedge resection of the wall of the IVC and suturing the primary IVC wall. Pathological findings led to a further diagnosis of the tumor as a leiomyosarcoma originating in the IVC. Thirty-seven months after the operation, multiple liver and lung metastases were detected, and the patient died from multiple organic failures. Conclusion. We experienced a rare case of a leiomyosarcoma of IVC mimicking hepatic tumor.

Surgical resection of hepatic cystic echinococcosis impaired by preoperative diagnosis.

Cystic echinococcosis (CE) is a rare afferent infectious disease in Japan. This paper reports a case of a hepatic cyst being diagnosed after surgical resection. A 40-year-old Syrian male was admitted for evaluation of a hepatic cyst. Serum antibodies of echinococcosis were negative. Enhanced computed tomography of the abdomen revealed a large cystic lesion, 9 cm in diameter, in the left lateral sector of the liver, which had many honeycomb-like septa and calcified lesions. Magnetic resonance imaging of this lesion revealed high intensity in the T2 weighted image. We preoperatively diagnosed this lesion as cystadenocarcinoma or CE and performed a left hepatectomy. Pathological examination revealed the presence of protoscolices in the fluid of the cysts and led to a diagnosis of this lesion as CE. In conclusion, on seeing patients with huge hepatic cysts who come from an epidemic area, we should consider hepatic CE.