Segmental assessment on ordinary scintigrams and SPECT images of the liver

By examining the area of defect elucidated on the scintigrams and SPECT (single photon emission computed tomography) images, the extension of the tumor into segments was assessed in cases where the SOL (space-occupying lesion) was determined by other methods. In this study, we followed the Couinaud 's segmentation. As a result, it was found that the segment with a SOL could be diagnosed fairly well on radionuclide images. Some incorrect assumptions were also found about the segments on ordinary scintigrams in previously published articles. These incorrect assumptions have been accepted for a long time. Although we do not deny that TCT (transmission X-ray computed tomography), echography, angiography, etc. are necessary for a precise judgment on liver segment and also that there are some cases in which the segmental assessment of these radionuclide images is impossible, we do believe that this kind of effort will improve the diagnostic capability of the radionuclide images.

[Development on segmentectomy and subsegmentectomy of the liver due to introduction of ultrasonography]

Due to introduction of preoperative and intraoperative ultrasound into liver surgery, three dimensional structure of the liver is understood much better than before. Intraoperative sonography demonstrated many daughter nodules and tumor thrombi which were not detected preoperatively. Therefore, a part of noncurative resection of the liver can be avoided. In patients with liver cirrhosis and small hepatoma, 60 per cent of hepatomas could not be visible nor palpable from the surface of the liver. In these patients, if hepatic lobectomy is performed, liver dysfunction will develop after surgery. Therefore, small partial resection is indicated and identification of site of the tumor is indispensable. With intraoperative sonography, all invisible and nonpalpable tumors in the liver were demonstrated. Clinicopathological studies of the hepatocellular carcinoma suggest that the tumor cells spread in the liver through the portal venous branches even in the small hepatocellular carcinoma. Daughter nodules will grow in the distal region of the portal venous branch. Therefore, total resection of the subsegment which contains the tumor is indicated. For this purpose, systematic subsegmentectomy is considered. In this operation, portal area containing tumor is identified by ultrasonically guided puncture of the portal venous branch. By identification of the inferior right hepatic vein, the right postero-inferior area can be preserved, even if right hepatic vein is resected. This type of hepatectomy is called inferior right hepatic vein preserving operation. We already performed this operation in three patients.

[Significance of major hepatectomy for metastatic liver malignancy]

Major hepatectomies for 24 metastatic liver tumors including 13 of colo-rectum origin were performed. The cumulative survival rate in 23 cases excluding one case of operative death is 67.4%, 44.3% and 29.1% for 1, 3 and 5 year, respectively. The significant difference was observed in survival rate between H1(n = 16) and H2 - 3 (n = 7). In colo-rectum origin group the survival rate of solitary H1 was better than that of multiple H1 significantly. The Japanese Colon Cancer Research Meeting reported the relative survival rate of 33 cases of H1 colo-rectum origin including 2 of hepatectomized cases. The survival rate of the present 11 hepatectomized cases in the same category is significantly better than that in the report of Colon Cancer Research Meeting, which shows utility of hepatectomy for H1 metastatic tumor. Although in H2 - 3 group 5 of 7 cases died within one year after hepatectomy, 2 particular cases survived 22 months and 57 months. The primary lesions of these two were leiomyosarcoma of the jejunum and carcinoid tumor of the lung. The indication for major hepatectomy for metastatic liver malignancy is the tumor of H1, especially solitary and the slow growing or some kind of functioning tumor.

The inferior right hepatic vein: ultrasonic demonstration

The inferior right hepatic vein (IRHV) was demonstrated sonographically in 27 out of 269 patients (10%). It was shown to be thicker than the right hepatic vein in 8 (3%). In 2 patients, two accessory right hepatic veins were demonstrated, with one being the IRHV and the other the middle right hepatic vein. Delineation of the IRHV is significant in hepatectomy, detection of tumor thrombus in hepatocellular carcinoma, Budd-Chiari syndrome, and dilatation of the intrahepatic bile ducts.

Hepatocellular carcinoma. A clinical and pathologic analysis of 57 hepatectomy cases

The following is a clinicopathologic analysis of 57 hepatectomy cases of hepatocellular carcinoma (HCC). The rates of complication from precirrhosis and cirrhosis were 33.3% each. Cirrhosis seemed to have preceded HCC in 13 cases (39.4%) and both diseases appeared to have developed simultaneously in 18 cases (54.5%). Growth patterns of HCC were related to histologic features of livers bearing HCC: HCCs occurring in normal livers were significantly larger in average tumor size than those occurring in cirrhotic livers (9.2 as compared to 4.7 cm) and tended to exhibit a microtrabecular growth pattern (83% of the cases), while HCCs occurring in cirrhotic livers were most commonly macrotrabecular (67%). The factors most significantly influencing survival were the smallness of removed liver and tumor, histologic grades, the presence of bile production, and the absence of satellite tumors and giant cells. The positivity rates of serum hepatitis B virus (HBV) surface antigen averaged 47.2% and the relation of HCC to the role of HBV in the pathogenesis of HCC was discussed.

Intraoperative ultrasonic examination for hepatectomy

Intraoperative ultrasonic examination (IUE) was performed on 118 patients who were laparotomized for hepatectomy with five types of specially designed real-time linear array transducers. Many lesions which were invisible and nonpalpable from the surface of the liver were present in 58% of patients. All these lesions were detected by IUE. Among 16 tumors in 13 patients, IUE demonstrated 11 tumor thrombi (69%). By angiography, definite and equivocal diagnosis was made only in six tumor thrombi. Systematic subsegmentectomy was performed in 41 cases. The new concept of partial hepatectomy was accomplished by IUE. IUE is an indispensable operative procedure for hepatectomy.

Ultrasonographic diagnosis and drainage in noncalculous acute cholecystitis following surgery

Postoperative acute cholecystitis is not so rare complication especially in postgastrectomy patients. Ultrasonic examination is the most suitable means of identifying postoperative acute cholecystitis. 24 patients were diagnosed as postoperative acute chlecystitis mainly by ultrasonic examination. The majority of cases recovered only by conservative treatment. Clinically severe cases are particularly indicated for ultrasonically guided percutaneous transhepatic gallbladder drainage. Moreover, patient with postoperative acute cholecystitis are considered to require follow-up studies after recovery.

Ultrasonic characteristics of the small hepatocellular carcinoma

Fifty five small hepatocellular carcinoma less than 5 cm in diameter among 41 patients were examined by linear arrayed electronic scanning system with 3.5 MHz transducer. Characteristics of the sonogram were enhanced posterior echoes of the tumor, mosaic pattern of internal echoes, halo and lateral shadows. These findings are appeared in 69%, 64%, 35% and 22% of tumors respectively. Among 45 tumors from 2.1 cm to 5 cm in diameter, these findings are appeared in 81%, 73%, 40% and 24% respectively. Among 10 tumors less than 2 cm in diameter, these characteristics were rare and these minimal hepatocellular carcinomas were demonstrated as a simple low echo area. Fifty tumors in 39 patients were resected. Lobulation of the hepatocellular carcinoma on the cut surface of the resected specimen and mosaic pattern on the sonogram are closely connected with each other. Thin fibrous capsule of the hepatocellular carcinoma corresponded to halo and lateral shadows. Posterior echo enhancement was due to the softness of the hepatocellular carcinoma. By those four characteristics, hepatocellular carcinoma can be differentiated from hemangioma and metastatic liver tumor.

Ultrasonically guided percutaneous transhepatic bile drainage: a single-step procedure without cholangiography

Percutaneous transhepatic bile drainage under real-time ultrasonic guidance was performed in 16 patients (21 procedures) without cholangiography. All bile ducts were successfully intubated. Merits of ultrasonically guided percutaneous transhepatic bile drainage are (a) the fact that only a single step is involved, without thin-needle cholangiography; (b) no contrast medium is injected; (c) the left-sided approach permits longer intubation; and (d) irradiation is not employed.

Sonographic differentiation between the umbilical portion of the left portal vein and intrahepatic bile ducts

The method of differentiating between the portal vein and the bile ducts by means of their intrahepatic portions was studied. The left branch of the portal vein courses horizontally as the transverse portion, then veers anteriorly at an acute angle to make the umbilical portion. This characteristic form was demonstrated in all normal controls and 95% of the jaundiced patients studied. The left hepatic duct does not curve anteriorly at an acute angle, but branches off to the lateral segment running superior to the umbilical portion. This anatomic relationship and characteristic form of the umbilical portion were useful in differentiating the portal vein and the bile ducts.

Ultrasonically guided percutaneous transhepatic cholangiography and percutaneous pancreatography

Ultrasonically guided percutaneous transhepatic cholangiography and percutaneous pancreatography were successfully performed in a patient with periampullary carcinoma. The entire biliary tree, including the dilated pancreatic duct, was visualized on both occasions. The techniques used are described, and the clinical significance of ultrasound as a guide in percutaneous puncture is discussed.

Echo guided percutaneous transhepatic cholangiography with puncture transducer

Conventional percutaneous transhepatic cholangiography (PTC) has some disadvantages because it is customarily performed blindly. If the bile duct is made visible, these disadvantages are eliminated. The biliary tree, if dilated, can be clearly delineated by ultrasound technique. By combining the B-mode examination of the biliary tract with the ultrasonic puncture transducer, percutaneous transhepatic cholangiography was performed successfully in 16 examinations on 12 patients. PTC needle could be inserted directly into the lumen of the bile duct without appreciable difficulty. The echo guided PTC was found to be an easier, safer, and more reliable method than the conventional blind technique.