Biomedical subjects

K Konno

Publications and source records attributed to K Konno.

At least 649 records · Page 36Linked to original sources

PubMedDate not supplied

Adenosquamous carcinoma of the pancreas: report of two cases.

Adenosquamous carcinoma (ASqC) of the pancreas is a rare tumor. We analyzed the radiologic findings and clinical manifestations in two such cases. In both cases (a 51-year-old woman and a 67-year-old man), the portal system was selectively and largely invaded, the superior mesenteric vein in one and the splenic vein in the other, without arterial invasion. Thus, peripancreatic vessels should be carefully observed in patients with ASqC of the pancreas. One case showed an unusual mode of spread. Only a huge metastatic lesion was initially detected, leading to the misdiagnosis of primary malignant mesenteric tumor. Such an unusual growth pattern is also worth noting.

Aged↗

PubMedDate not supplied

Liver tumors in children and young patients: sonographic and color Doppler findings.

BACKGROUND: Liver tumors are a relatively rare pathologic condition in children and young patients. The aim of the present study was to categorize the sonographic (US) and color Doppler results of liver tumors in these patients. METHODS: We retrospectively reviewed the US findings of 23 such cases: malignant tumor (13 cases)-hepatoblastoma (four cases), hepatocellular carcinoma (HCC; four cases), and hepatic metastasis (five cases); benign tumor (10 cases)-hepatocellular adenoma (four cases), focal nodular hyperplasia (two cases), mesenchymal hamartoma (two cases), cystadenoma (one case), and hemangioendothelioma (one case). RESULTS: There was no specific US findings for each tumor type. HCC usually developed on a normal liver and was imaged as multiple nodules. Color Doppler US helped in differentiating multiple metastatic nodules (hypovascular) from multiple HCC nodules (hypervascular). Presence of intratumoral cystic areas was usually suggestive of benign tumors. Follow-up US was useful for detecting small nodules in high-risk groups (congenital biliary atresia, glycogen storage disease). Color Doppler US helped in diagnosing portal thrombus or intratumoral shunt. CONCLUSION: Although there were no highly specific findings, US and color Doppler results contributed, to a certain degree, to the diagnosis of liver tumors in children and young adults by showing intratumoral cystic areas or vascularity.

Adolescent↗

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Abdominal involvement in neurofibromatosis 1: sonographic findings.

BACKGROUND: Neurofibromatosis 1 (NF1) has been studied from many viewpoints, but its abdominal involvement has rarely been reported. Sonography (US) is now the initial diagnostic tool for abdominal exploration, which prompted us to determine the clinical manifestations and US findings of abdominal involvement in NF1. METHODS: We analyzed the US findings and clinical data of eight NF1 cases with abdominal involvement. RESULTS: Abdominal involvement included neurofibromatous tumor growth in the liver, mesentery, and retroperitoneum, in addition to mesenteric leiomyomatosis and gastric carcinoma. Color Doppler US was useful not only in detecting blood flows in the lesions but also in preventing hazardous vascular injury during tumor biopsy. CONCLUSION: A better understanding of the clinical manifestations and US findings of abdominal involvement in NF1 translates into improved NF1 patient care.

Abdominal Neoplasms↗

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Retroperitoneal liposarcoma: sonographic findings.

This study, based on sonographic (US) results of 10 cases with histologically proven retroperitoneal liposarcoma (eight well-differentiated and two pleomorphic types), shows that the presence of fine echogenic lines within the tumor is a useful sign for diagnosing a well-differentiated liposarcoma. Presence of numerous fine fibrous septa in the lipomatous tumor tissue is thought to be responsible for this interesting phenomenon. Of interest is the fact that the direction of these lines changed according to the probe format used: parallel horizontal lines when using a linear probe and concentric lines converging toward the probe when using a sector or curved linear probe. In contrast, pleomorphic liposarcoma does not show this US sign. Knowledge of these US findings is useful for the diagnosis of retroperitoneal liposarcoma.

Adult↗

PubMedDate not supplied

Macronodular hepatic deformity on normal liver.

BACKGROUND AND METHODS: Macronodular hepatic deformity on normal liver is very rare. We present nine such cases and try to define the characteristic clinical and ultrasound (US) findings. RESULTS: In the left lobe, the lateral segment was replaced by multiple nodules and the medial segment was very atrophied and irregularly shaped. Compared with the left lobe, the right lobe showed very few abnormalities except for segment 6, which showed a macronodular deformity. These nodules, regardless of diameter or lobe, showed a relatively homogeneous internal structure and were isoechoic relative to the surrounding hepatic parenchyma. These multinodular changes on US corresponded to multiple regenerative nodules identified at laparoscopic evaluation. On color Doppler US and angiography, the major intrahepatic vessels were patent in all cases. CONCLUSION: Although relatively rare, the macronodular hepatic deformity on normal liver collected in our series showed a characteristic appearance by US. A good understanding of its characteristics may help sonographers in differentiating it from other, more common hepatic deformities.

Adult↗

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Pancreatic metastasis: sonographic findings.

BACKGROUND: Pancreatic metastasis is a relatively rare pathologic condition. Its ultrasound (US) findings have been infrequently reported, and there has been no previous report describing its color Doppler findings. METHODS: We reviewed the US findings of 13 such cases. RESULTS: The pancreatic metastasis consisted of a single hypoechoic nodule in four cases and multiple hypoechoic nodules in nine cases. US showed a slight dilatation of the main pancreatic duct in two cases of pancreatitis, and a marked biliary dilatation in one case of jaundice. The US results prompted introduction of appropriate treatment in these cases. Color Doppler US was useful for confirming the absence of flow abnormalities in the arterial and portal systems around the pancreas. In a patients with renal carcinoma metastasis, it showed many fine blood flow signals in the metastatic lesions. CONCLUSION: The role of US in the diagnosis of pancreatic metastasis consists of associated complications such as biliary dilatation or pancreatitis and detection of isolated lesions. Additional information provided by color Doppler US may increase diagnostic confidence.

Adult↗

PubMedDate not supplied

Pancreatic uncinate carcinoma: sonographic findings.

BACKGROUND: Pancreatic carcinoma arising from the uncinate process (pancreatic uncinate carcinoma) is relatively rare. We wished to define its clinical manifestations and sonographic findings. METHODS: Clinical and sonographic data of eight cases were reviewed. RESULTS: The common bile duct and the pancreatic duct were not dilated until a very late stage. The lesion mimicked a mesenteric tumor in two cases. The superior mesenteric vessels were compressed anteriorly. Computed tomography was useful, not only for confirming the pancreatic uncinate origin of the lesion but also for determining precisely the mode of mesenteric vascular involvement. CONCLUSION: Knowledge of these unusual sonographic findings can determine the diagnostic strategy in pancreatic uncinate carcinoma.

Aged↗

PubMedDate not supplied

Macronodular deformity of the spleen.

BACKGROUND AND METHODS: Macronodular splenic deformity without a focal lesion has rarely been reported. We present three such cases and discuss the possible pathomechanism. RESULTS: There was one case of macronodular deformity of unknown cause. In this case, the liver was elongated anteriorly over the dome of the spleen, and the markedly deformed spleen mimicked a round lesion in the left lobe of the liver. Color Doppler ultrasonography showed the major intra- and perisplenic vessels to be patent. There were two cases of macronodular deformity associated with extended portal thrombosis. In both cases, portal thrombosis extended throughout the intrahepatic and extrahepatic portal systems, and this portal flow disturbance was presumed to be the cause of the splenic deformity. CONCLUSION: Although very rare, thrombosis should be sought throughout the portal system when ultrasonography shows a markedly deformed spleen. Marked splenic deformity, especially in cases with an elongated liver, may mimic a liver tumor. A good understanding of its sonographic appearance may help sonographers prevent a hazardous misdiagnosis.

Adult↗

PubMedDate not supplied

Choledochal cyst due to anomalous pancreatobiliary junction in the adult: sonographic findings.

BACKGROUND: Adult cases of choledochal cyst due to anomalous pancreaticobiliary duct junction have been rarely reported. At present, sonography (US) is the first tool for diagnosing biliary disorders. The aim of this study was to reevaluate the US findings of choledochal cysts due to anomalous pancreaticobiliary duct junction in adults. METHODS: We reviewed the clinical manifestations and US findings of 12 such adult cases confirmed by endoscopic retrograde cholangiopancreatic ductography (ERCP). Patients were assigned to three groups: (a) associated with biliary carcinoma (two cases), (b) associated with choledocholithiasis (one case), and (c) not associated with other abdominal diseases (nine cases). RESULTS: Patients in group c were asymptomatic, and the lesions were detected incidentally detected by US. In contrast, patients in group a sought medical care because of symptoms such as jaundice and those in group b sought medical attention because of abdominal pain. The diameter of a dilated bile duct on US was considerably less than that of ERCP (ERCP: 26-58 mm, mean = 37.6 mm; US: 13-32 mm, mean = 21.8 mm). Its diameter changed significantly under probe compression when the dilated bile duct took a purely cystic form but changed very little when it took a tubular form. CONCLUSION: Unlike cases in children, adult cases of choledochal cyst are generally asymptomatic. Careful US observation of the bile duct is thus expected to detect asymptomatic adult choledochal cysts cases. Cyst diameter can change significantly under probe compression, so it is important not to compress the bile duct during routine US examination.

Adult↗

PubMedDate not supplied

Duodenal carcinoma: sonographic findings.

BACKGROUND: Duodenal carcinoma is a relatively rare tumor and its sonographic (US) findings have rarely been reported. METHODS: We reviewed the clinical data and US results of 15 patients with histologically proven duodenal carcinoma to pinpoint the contribution of US to the diagnosis. RESULTS: US was useful for not only detecting the duodenal carcinoma (13 of 15, 86.7%), which altered the endoscopic procedure in nine patients, but also for evaluating vascular involvement (marked portal invasion in four cases and inferior vena cava invasion in two cases). Four of the eight carcinomas arising from the second or third portion showed this vascular invasion. CONCLUSION: After reviewing the clinical data and US results of 15 cases of duodenal carcinoma, we found that US was useful for detecting duodenal carcinoma and determining vascular invasion. Thus, US contributed significantly to alter the endoscopic procedure and patient management.

Carcinoma↗

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Mycotic abdominal aneurysm: report of a case with emphasis on the presence of gas echoes.

Mycotic abdominal aneurysm is a relatively rare disease and its sonographic (US) findings have rarely been reported. We present a case of mycotic aneurysm of the common iliac artery in which the initial US showed a slightly wall-thickened abdominal aorta with gas echoes in the wall, a second US 6 days later showed a rapid increase in aortic size, and an emergent surgical intervention showed a mycotic aneurysm. This interesting observation suggested that the presence of gas echoes is a useful US finding indicating the beginning of a mycotic aneurysm and, when encountering this US finding, that emergent treatment should be considered to prevent delay in patient management.

Aged↗

PubMedDate not supplied

Peripheral bone metastasis from hepatocellular carcinoma: sonographic findings.

BACKGROUND AND METHODS: We reviewed medical and radiologic records of five patients with bone metastasis from hepatocellular carcinoma (HCC) to evaluate the role of sonography (US) in the diagnosis of this bone metastasis. RESULTS: The metastatic lesions were clearly visualized by US as expansive, homogeneous, soft tissue masses with bony destruction, and color Doppler US showed fine vessels within the lesions. After treatment, US showed a decrease in tumor size with an increase in echogenicity and a decrease in blood flow. Hepatic US at the time of bone metastasis showed a portal tumor thrombus in all cases. CONCLUSION: When US detects a portal venous tumor thrombus in HCC patients, attention should be directed not only to the liver but also to bone to improve patient care. US is useful not only in detecting the metastatic lesion but also in evaluating the treatment effect.

Bone Neoplasms↗

PubMedDate not supplied

Portal hypertension in children and young adults: sonographic and color Doppler findings.

Portal hypertension is a relatively uncommon pathologic condition in children and young adults in contrast with older adults. The aim of this study is to evaluate the utility of sonography and color Doppler sonography in the diagnosis of portal hypertension in children and young patients and to evaluate the sonographic pattern of each disease. We reviewed 25 such patients who were younger than 30 years old and obtained the following sonographic findings: (1) liver cirrhosis: (a) multiple intrahepatic venovenous shunts in patients with primary Budd-Chiari syndrome and (b) intrahepatic vascular narrowing and nodular coarse parenchymal texture, with multiple very-high-echo spots along the portal vein in patients with Wilson disease; (2) congenital hepatic fibrosis: marked and developed collaterals, wide periportal echogenic band, and a heterogeneous parenchymal texture comprised of multiple high echoes but without portal thrombus; and (3) extrahepatic portal thrombosis: invisible portal lumen except as an echogenic band. Sonography and color Doppler sonography are very useful in diagnosing these portal hypertensive diseases. However, there are no specific sonographic findings, and the role of sonography is limited to follow-up observation of associated secondary hepatobiliary changes in patients with congenital biliary atresia.

Adolescent↗

PubMedDate not supplied

Large extrahepatic portosystemic shunt without portal hypertension.

Extrahepatic portosystemic shunt usually occurs secondary to severe portal hypertension, and it is rare to encounter it in patients without portal hypertension. We report herein a large extrahepatic portosystemic shunt between the left gastric vein and left renal vein without portal hypertension in which color Doppler sonography was useful not only for detection but evaluation of the effect of embolization.

Embolization, Therapeutic↗

PubMedDate not supplied

Portal vein aneurysm: report of six cases and review of the literature.

Portal vein aneurysm is very rare, and its relation to portal hypertension has been emphasized. We report six cases of portal vein aneurysm (five extrahepatic and one intrahepatic). All patients were asymptomatic and had no signs suggestive of portal hypertension; the lesion was incidentally detected by ultrasound. Color Doppler sonography showed a constant hepatopetal flow along the aneurysmal wall, which immediately led to the diagnosis. We stress the usefulness of color Doppler sonography for studying the hemodynamics of this vascular anomaly and briefly review the literature.

Aneurysm↗

PubMedDate not supplied

Color Doppler findings of gastrointestinal varices.

BACKGROUND: Compared with esophageal varices, gastrointestinal varices are relatively rare, but they are clinically important because they tend to bleed massively. Color Doppler sonography is now widely used to diagnose the collaterals, but few color Doppler findings of gastric or intestinal varices have been reported. The aim of this study was to investigate the sonographic and color Doppler findings of gastrointestinal varices and to determine the role of color Doppler sonography in the diagnosis of these varices. METHODS: We studied 30 patients who were diagnosed by endoscopy as having gastrointestinal varices (24 gastric, four duodenal, two intestinal) with color Doppler sonography and compared the results with the clinical data. The causes of gastric varices included liver cirrhosis (16/24, 66.7%), idiopathic portal hypertension (3/24, 12. 5%), chronic pancreatitis with splenic vein thrombosis (2/24, 8.3%), congenital biliary atresia (1/24, 4.2%), congenital hepatic fibrosis (1/24, 4.2%), and unknown (1/24, 4.2%). The causes of duodenal varices included idiopathic portal hypertension with portal thrombosis (3/4, 75%) and liver cirrhosis (1/4, 25%). RESULTS: The gastric wall at the fundus was thickened in 17 of 24 cases (70.8%) with gastric varices, and the duodenal wall was thickened in four of four cases (100%) with duodenal varices. Sonography revealed thrombosis in the splenic vein in two of two cases with gastric varices secondary to chronic pancreatitis and in the confluence of the superior mesenteric vein and the splenic vein in three of four cases with duodenal varices. Color Doppler sonography demonstrated multiple, slow constant blood flows in the thickened wall in 15 of 24 cases (62.5%) with gastric varices and in four of four cases (100%) with duodenal varices. It demonstrated accumulated slow constant blood flows in the cecum in the case with cecal varices. Color Doppler showed also the communication between the varices and the neighboring vascular system (superior mesenteric vein and inferior vena cava) in the case with cecal varices, but it did not directly reveal such a communication in the other 29 cases (96.7%). Color Doppler showed a hepatofugal flow in the left gastric vein in all the hemorrhagic gastric varicose patients with esophageal varices, but it showed a hepatopetal flow in the left gastric vein in the isolated nonhemorrhagic gastric varicose patients. CONCLUSION: Color Doppler sonography was very useful for the diagnosis of gastric and duodenal varices and for visualizing fine venous flows in the thickened gastric or duodenal wall. When it shows portal thrombosis in the confluence of the splenic vein and the superior mesenteric vein, duodenal varices should be suspected. The flow direction of the left gastric vein helps to differentiate hemorrhagic gastric varices from nonhemorrhagic ones.

Adolescent↗

PubMedDate not supplied

Sonographic findings of anomalous position of the gallbladder.

Anomalous position of the gallbladder is relatively rare and has been reported only in isolated case reports. We tried to determine its ultrasound (US) findings on the basis of 18 such patients. In the left-side gallbladder group (nine patients), the gallbladder was imaged as an oval cystic mass in front of the pancreas. In all patients, the narrow neck of the gallbladder was clearly detected by US in the usual location before the main portal vein. Four of nine patients had small gallbladder stones. The retrohepatic gallbladder group (four patients) showed marked atrophy of the right lobe of the liver. Two patients had multiple gallstones in the bile ducts of the right lobe. All patients in the suprahepatic retrohepatic gallbladder group (four patients) were cirrhotic, and the anterior segment of the right lobe was markedly atrophied. In the intercostal scan, the gallbladder mimicked a perihepatic fluid. In the floating gallbladder group (one patient), the gallbladder was imaged as a cystic mass in the anterior abdominal wall. Surgical intervention showed a severely inflamed gallbladder, with small stones adhered into the anterior abdominal wall and partially ruptured. Knowledge of the wide range of US findings of malposition of the gallbladder helps in avoiding misdiagnosis.

Adult↗

PubMedDate not supplied

Lobar atrophy of the liver.

Lobar atrophy of the liver due to causes other than liver tumor or liver cirrhosis is a relatively rare pathological condition, and there are only a few reports in the literature. We report six such cases and try to evaluate the relationship between lobar atrophy and portal flow disturbance. The patients could be divided into two groups according to the site of the atrophy: those with atrophy of the left lobe (two cases) and those with atrophy of the right lobe (four cases). The two cases with atrophy of the right lobe had hepatholithiasis in the involved segments, but the cause was not determined in the remaining four cases. In all six cases, portal flow disturbance was noted, including invisibility of the portal vein in four cases, narrowing in one case, and portal thrombus in one case. Collateral circulation was not recognized in any of our cases. Of interest is the mode of lobar atrophy. Atrophy of the right lobe was always associated with marked enlargement of the left lobe, but that of the left lobe did not induce an enlargement of the right lobe.

Aged↗