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T Fukuya

Publications and source records attributed to T Fukuya.

At least 19 recordsLinked to original sources
PubMed1997

Small hepatocellular carcinoma on magnetic resonance imaging. Relation of signal intensity to angiographic and clinicopathologic findings.

RATIONALE AND OBJECTIVES: The authors discuss the clinicopathologic features and angiographic vascularity of various signal intensity patterns on magnetic resonance (MR) imaging of small hepatocellular carcinomas (HCCs). METHODS: Magnetic resonance images of 88 resected HCCs (< or = 3 cm) were obtained using T1- and T2-weighted spin-echo images and T1-weighted images after gadolinium (Gd)-DTPA administration. Images were compared with angiographic and histopathologic findings. RESULTS: Forty HCCs (45%) were depicted on T1-weighted images, 51 (58%) on T2-weighted images, and 41 (49%) on T1-weighted images after Gd-DTPA administration. Overall, 64 (76%) were found on at least one image. On T1-weighted images, hyperintense HCCs histologically showed fatty metamorphosis and portal tracts within the tumor. On T2-weighted images, HCC hyperintensity correlated with expansive growth, peliotic change, and hypervascularity. By contrast, HCCs that were undetected or hypointense on T2-weighted images were well differentiated with replacing growth and portal tracts. On T1-weighted images after Gd-DTPA, hyperintense HCCs had peliotic change; undetected HCCs were well differentiated and hypovascular. CONCLUSIONS: Histologic grade, vascularity, portal tracts and peliotic change correlate with MR signal intensity. For hyperintense HCCs on T1-weighted images and hypo- or isointense HCCs on T2-weighted images, treatment methods must be assigned with the consideration that HCCs may be receiving transsinusoidal and portal blood supplies.

Adult↗
PubMed1995

Small hepatocellular carcinomas undetected on two-phased incremental computed tomography. Angiographic and clinicopathologic findings.

RATIONALE AND OBJECTIVES: To elucidate the characteristic clinicopathologic features of hepatocellular carcinomas (HCCs) undetected on two-phased incremental computed tomography (CT). METHODS: Computed tomographic scans of 115 surgically resected small (< or = 3 cm) HCCs from 83 patients were performed 45 seconds and 6 minutes after the administration of contrast material. These scans were compared with corresponding angiographic and histopathologic findings. RESULTS: Eighty HCCs (70%) were depicted on the early images; 73 (63%) on the delayed images; and 89 (77%) using two-phased incremental CT. The small HCCs undetected on the early images but seen histologically had the following characteristics: (1) absence of a fibrous capsule, (2) well-differentiated tumor, (3) replacing growth patterns of the tumors, (4) lack of fatty metamorphosis and/or clear cell changes, (5) hypovascular on angiography. Those not seen on delayed images had the following characteristics: (1) absence of a fibrous capsule, (2) replacing growth patterns, and (3) presence of portal tracts in the tumors. CONCLUSIONS: The replacing growth pattern and the presence of portal tracts correlate with the undetectability on CT. For HCCs undetected on CT, treatment methods must be considered carefully, because the HCCs may be receiving transsinusoidal and portal blood supplies.

Adult↗
PubMed1995

Lymph-node metastases: efficacy for detection with helical CT in patients with gastric cancer.

PURPOSE: To determine the efficacy of helical computed tomography (CT) in the detection of lymphadenopathy in patients with gastric cancer. MATERIALS AND METHODS: Helical CT (5-mm section thickness, 5-mm/sec table incrementation) was performed in 58 patients (39 men, 19 women; mean age, 63.8 years) with gastric cancer; 1,082 lymph nodes (138 positive, 944 negative for metastasis) were resected at surgery. Findings at CT and resection were compared. Sensitivity for detecting lymph nodes was evaluated according to nodal size and presence of metastasis. RESULTS: Seven (1.1%) of 649 lymph nodes 1-4 mm, 160 (45.1%) of 355 nodes 5-9 mm, and 56 (72%) of 78 nodes larger than 9 mm were detected at CT. For nodes of at least 5 mm, sensitivity for detecting metastasis-positive nodes (79 [75.2%] of 105 nodes) was higher than that for detecting metastasis-negative nodes (137 [41.8%] of 328; P < .01). Differences between positive and negative nodes in CT attenuation (110 HU +/- 25 vs 66 HU +/- 32) and short-to-long axis ratios (0.81 +/- 0.15 vs 0.57 +/- 0.15; P < .001) were significant. CONCLUSION: Helical CT is effective for detection of metastatic lymphadenopathy from gastric cancer. CT attenuation and lymph-node configuration aid in diagnosis of malignant adenopathy.

Adult↗
PubMed1995

[Intra-bile duct growth of hepatocellular carcinoma: value of biliary dilatation on CT].

In order to evaluate the usefulness of CT in demonstrating biliary invasion by hepatocellular carcinoma, 191 surgically proved cases were studied. Among 191 CT scans performed before surgery, six (3%) showed biliary dilatation. Pathological biliary invasion was found in eight cases (4%). Of these eight cases, four cases (50%) showed biliary dilatation on CT. In six cases with biliary dilatation on CT, pathological biliary invasion was revealed in four cases (67%). In two cases, the large (> or = 6cm) encapsulated tumors located in the hepatic hilum dilated the intrahepatic bile duct without intraductal tumor growth. We concluded that biliary dilatation on CT cannot be a sign of biliary invasion by hepatocellular carcinoma.

Adult↗
PubMed1995

MR imaging of hepatocellular carcinoma. Correlation of metal content and signal intensity.

In order to clarify the factors contributing to the signal intensities (SIs) of HCC on T1-weighted images, the amount of water, lipid, copper (Cu), iron (Fe), and manganese (Mn) was determined in HCC and surrounding hepatic parenchyma of 13 patients. The relationships among these findings, the histopathologic findings, and the SIs of T1-weighted images were evaluated. Among the 13 HCC, 3 had a high SI, 5 were isointense, and 5 had a low SI on T1-weighted images compared to the surrounding hepatic parenchyma. The paramagnetic ions which contributed to the SI patterns were assumed to be Cu in HCC (38.0 +/- 62.4 micrograms/g ww), and Fe in the liver (61.1 +/- 42.4 micrograms/g ww) and HCC (40.0 +/- 34.3 micrograms/g ww). In 8 HCC with high- or isointensity, 2 were grades I, 5 were grade II, and one was grade III according to the Edmondson-Steiner's histopathologic classification. It is concluded that the SI patterns alone can not be a sign of low grade malignancy because of the existence of Fe in livers and HCC.

Aged↗
PubMed1995

[Selective intra-arterial injection of calcium for localization of insulinomas: proposed new criteria].

To elucidate whether noninvasive arterial stimulation venous sampling (ASVS) is helpful for localizing insulinomas, calcium gluconate (0.02-0.025 mEq Ca2+/kg) was injected directly into the gastroduodenal, splenic and superior mesenteric arteries of six patients with episodic hypoglycemia. In all six patients, there was a greater than 26-fold increase in serum insulin levels in blood samples obtained from the hepatic vein after the infusion of calcium into the artery supplying the tumor. However, in four of the six patients, such an injection into an artery not supplying the tumor resulted in a greater than twofold increase in insulin concentration. Accurate localization of the insulinomas was verified at surgery in all patients. We believe that these false positive results were caused mainly by the influx of calcium via branches of intrapancreatic anastomoses. In order to minimize false positive results, we have recommended the following new criteria for ASVS: maximum insulin concentrations exceeding 150 microU/ml in blood samples obtained from the hepatic vein, and greater than twofold increases in insulin concentration. We concluded that noninvasive ASVS is helpful in determining the location of insulinomas.

Adult↗
PubMed1994

CT of intraabdominal desmoid tumors: is the tumor different in patients with Gardner's disease?

OBJECTIVE: A retrospective study of abdominal CT scans of patients with proved intraabdominal desmoid tumors was done to determine if any objective characteristics exist to differentiate desmoids related to Gardner's syndrome from isolated desmoids. Because the desmoid tumors of Gardner's syndrome can predate the diagnosis of Gardner's syndrome, it would be helpful to know which patients with desmoids need careful follow-up studies as well as initial workup for Gardner's syndrome and all its ramifications. Also, it would be important to differentiate benign from malignant desmoids associated with Gardner's syndrome. It was hoped that the location, enhancement characteristics, and/or the presence or absence of infiltration might be of value. We were interested in noting if, over time, the growth characteristics of desmoids found in Gardner's syndrome were different from those of isolated desmoids. MATERIALS AND METHODS: We reviewed 101 abdominal CT scans obtained in 23 patients during a 13-year period. Forty desmoid tumors were intraabdominal, including 30 lesions associated with Gardner's syndrome in 13 patients and 10 desmoids of the idiopathic form in 10 patients. These tumors were studied to define location; whether they were single or multiple; and whether they had any specific CT characteristics regarding margins, attenuation numbers, or contrast enhancement. RESULTS: Desmoid tumors associated with Gardner's syndrome were more likely to be multiple (38%, five of 13 patients) and to involve the mesentery (60%, 18 of 30 tumors) and the abdominal wall (40%, 12 of 30 tumors), whereas isolated desmoid tumors were singular (all 10 patients) and were located in the retroperitoneum (six cases), pelvis (three), and anterior wall (one). Desmoids related to Gardner's syndrome also tended to be smaller (mean diameter, 4.8 cm) than idiopathic desmoids (mean diameter, 13.8 cm). No differentiating CT characteristics regarding margins, attenuation numbers, or response to contrast material were ascertained. Ten new lesions (seven intraabdominal, three mesenteric) developed in three patients with Gardner's syndrome, whereas no new intraabdominal lesions developed in patients with idiopathic desmoids. Follow-up data on 16 surgically resected desmoids in nine patients (seven with Gardner's syndrome and two with isolated desmoids) revealed seven local recurrences (two in the two patients with isolated desmoids and five in two patients with Gardner's syndrome). CONCLUSION: No CT characteristics, such as attenuation values, margins, and response to the contrast material, were found that would enable differentiation between isolated intraabdominal desmoids and those associated with Gardner's disease. Desmoid tumors associated with Gardner's syndrome tend to occur in the mesentery and abdominal wall, whereas isolated desmoids involve the retroperitoneum and pelvis. When studying CT scans obtained over time, new lesions were noted to develop in a few of the patients with Gardner's syndrome (three of 13), whereas no new lesions were found in patients with isolated desmoids.

Adult↗
PubMed1994

Diagnosis of inflammatory pseudotumor of the liver: value of CT.

OBJECTIVE: Inflammatory pseudotumor of the liver is a localized mass consisting of a fibrous stroma and chronic inflammatory infiltrate without anaplasia. Diagnosis of this rare disease is important to avoid surgery. The purpose of this study was to determine if CT is useful in the diagnosis of this lesion. SUBJECTS AND METHODS: CT scans of nine patients with a proved diagnosis of inflammatory pseudotumor of the liver were reviewed. Diagnosis was made by the surgical resection in three patients and by percutaneous biopsy in six patients. Six patients had symptoms and laboratory data suggesting active inflammation caused by the pseudotumor. The remaining three patients were asymptomatic. CT scans were performed with IV administration of the contrast material; scans were obtained in the portal venous and delayed phases in six patients and in the delayed phase in three patients. CT scans were analyzed for the number and size of the hepatic masses, and the degree and pattern of contrast enhancement on portal venous phase and delayed-phase images. RESULTS: Eight patients had a solitary hepatic mass, and one patient had two masses on the CT scan. The average size of the masses in the symptomatic patients (8.3 cm) was larger than that in the asymptomatic group (3.6 cm). CT scans in the portal venous phase showed a variable degree of contrast enhancement (seven masses). At least a part of seven masses, six of which were in symptomatic patients, showed greater contrast enhancement on delayed-phase CT scans than on the normal liver parenchyma. No constant pattern of enhancement was observed on delayed-phase CT scans in asymptomatic patients. CONCLUSION: Inflammatory pseudotumor of the liver should be included in a differential diagnosis in patients with a hepatic mass on a CT scan, especially when patients are symptomatic and the mass is fairly large and solitary showing contrast enhancement greater than that of liver parenchyma on delayed-phase CT scans. Percutaneous biopsy should be performed to obtain a histologic confirmation.

Adolescent↗
PubMed1994

Ultrasonographic abdominal screening of atomic bomb-exposed subjects.

Abdominal ultrasonographic screening for cancer was performed in 6,001 Hiroshima and Nagasaki A-bomb exposed and comparison subjects, all members of the Adult Health Study of the Radiation Effects Research Foundation, formerly the Atomic Bomb Casualty Commission. This study yielded 20 cancers, including 7 hepatocellular, 3 gastric, 3 renal and 2 urinary bladder cancers; one cancer each of the ovary, pancreas, colon and ureter; and one cancer metastatic to the liver, whose primary was unknown. Seventeen of these 20 subjects manifested no symptoms or signs of their disease. A variety of additional tumors, unproven and probably benign, including uterine myomata, and other abnormalities were also detected. Abdominal ultrasonographic screening greatly assisted in the detection of cancers, most of which neither the patients nor their physicians were aware. In this screened fixed population sample the cancer detection rate was 0.33%, exceeding any such rates previously reported in the medical literature.

Abdominal Neoplasms↗
PubMed1993

Midgut volvulus as a complication of intestinal malrotation in adults.

Seven adults with midgut volvulus as a complication of malrotation are presented. All patients were men with an average age of 33 years. Four presented with long histories of intermittent abdominal pain. In three patients, the twisted, corkscrew appearance of the barium column in the duodenum and proximal jejunum in an upper gastrointestinal series made the diagnosis. In the remaining patient, small-bowel follow-through performed three years before surgery showed intestinal malrotation. Three patients presented with the acute onset of severe abdominal pain. Plain films showed small-bowel obstruction and pneumatosis intestinalis in two patients and only nearly complete small-bowel obstruction in the third. Barium studies were not done in this group because of the need to proceed to exploratory laparotomy and the risk of perforation. In one patient, abdominal angiography suggested the diagnosis by showing abnormal courses of the mesenteric vessels to the volvulized segment of small bowel. All three of these patients showed ischemic segments of bowel at laparotomy.

Abdomen, Acute↗
PubMed1993

Postoperative MRI evaluation of anorectal malformations with clinical correlation.

Sixteen postoperative patients with anorectal malformation were evaluated by MRI, and the results compared with the clinical assessment. Patients were classified into three groups--good (group 1, n = 10), fair (group 2, n = 3) and poor (group 3, n = 3)--on the basis of Kelly's clinical score of incontinence. The degree of development of the puborectalis and external sphincter muscles and the levator hammock was evaluated on MRI in comparison with patients without anorectal disease. The proportions of fair or poor development of the muscles were 37% in group 1,22% in group 2 and 67% in group 3. Although fair or poor development of the muscles was seen more frequently in group 3, there was no statistically significant difference between groups. However, poorly developed muscles were seen only in patients with fair or poor clinical scores. The difference in the anorectal angle measured on sagittal MRI images between patients in group 1 and groups 2 or 3 was significant. Our study indicates that MRI evaluation based solely on muscle development can be misleading, and measurement of the anorectal angle should be included in the MRI evaluation.

Abnormalities, Multiple↗
PubMed1993

Hepatocellular carcinoma: correlation of CT, angiographic, and histopathologic findings.

PURPOSE: To elucidate the causes of various enhancement patterns of hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: Computed tomographic (CT) scans of 68 surgically resected HCCs (62 patients) were obtained 45 seconds and 6 minutes after administration of contrast material. These scans were compared with angiographic and histopathologic findings. RESULTS: On the early images, 24 HCCs (35%) were hypoattenuating, 33 were totally or partially hyperattenuating (48%), and 11 were isoattenuating (16%) compared to adjacent liver. On the delayed images, 55 HCCs (81%) were hypoattenuating and 13 (19%) were isoattenuating. Twenty-nine of the 48 very hypervascular or hypervascular tumors (60%) were hyperattenuating or partially hyperattenuating at early CT. Sixteen of the 20 slightly hypervascular or hypovascular tumors (80%) were isoattenuating or hypoattenuating. CONCLUSION: Although there was relatively good agreement between tumor vascularity and enhancement pattern (60% correlation for hypervascular tumors, 80% correlation for hypovascular tumors), hyperattenuation of the large HCCs (> or = 5 cm) at CT appeared to be a function of dilated sinusoids within the tumor (peliotic changes) as well as vascularity. In patients with advanced cirrhosis, hypovascular HCCs could be hyperattenuating at CT.

Angiography↗
PubMed1993

Normal age-related alterations on chest radiography. A longitudinal investigation.

To ascertain serial changes on chest radiography attributable to aging, 16 parameters and 4 pulmonary parenchymal manifestations were assessed at 2 intervals; namely, 18.5 and 10 years after initial radiography in healthy men (n = 51) and women (n = 149) (age range 41-82 years). The transverse cardiac diameter, cardiothoracic ratio, and aortic arch transverse diameter increased significantly in both sexes from the initial to the final examinations. Although several other factors changed significantly, these changes were relatively small and the individual variations large. Initially, 13% and finally, 27% of the subjects exhibited at least one of the selected pulmonary manifestations.

Adult↗
PubMed1992

CT diagnosis of small-bowel obstruction: efficacy in 60 patients.

We retrospectively compared the CT findings in patients with and without surgically proved small-bowel obstruction to evaluate the role of CT in diagnosing the presence and cause of obstruction. In the patients with obstruction, we compared the CT findings with findings on plain abdominal radiographs and contrast studies of the small intestine. CT criteria used for the diagnosis of obstruction were dilated small-bowel loops proximal to the suspected site of obstruction and collapsed or normal-appearing loops of small bowel distal to the obstruction. Receiver-operating-characteristic analysis suggested the optimum balance of sensitivity and specificity was achieved when 2.5 cm was used to indicate dilatation of the small bowel. On the basis of these criteria, the presence of obstruction was correctly diagnosed in 27 (90%) of 30 patients with proved obstruction, and obstruction was not diagnosed in the patients without obstruction. The cause of the obstruction was evident on CT in 14 of the 30 obstructed patients: abscess (five), neoplastic lesion (three), peritoneal carcinomatosis (three), and other (three). Adhesions were responsible for the obstruction in 13 of 15 patients in whom the cause was not shown on CT. In six patients in whom findings on plain abdominal radiographs were normal, the CT scan was positive for obstruction. However, in the three patients whose CT scans were falsely negative for obstruction, findings suggesting obstruction were seen on plain films. Of 15 patients who had both CT and contrast studies of the small intestine, CT offered more information concerning the cause of obstruction in six (40%), primarily by demonstrating significant extraluminal abnormalities. CT and gastrointestinal contrast studies gave concordant results in eight patients with obstruction. In only one patient did the gastrointestinal contrast study give more diagnostic information. We conclude that CT scanning demonstrates accurately the presence of high-grade small-bowel obstruction and may be the technique of choice when extraluminal abnormalities are suspected or when prompt, efficient, and comprehensive evaluation is required.

Adult↗
PubMed1992

Hyalinizing trabecular adenoma.

A case is presented of hyalinizing trabecular adenoma in a 54-year-old Japanese female. The patient underwent a hemithyroidectomy for the diagnosis of thyroid carcinoma. An intraoperative frozen section diagnosis was medullary carcinoma. Hematoxylin and eosin stained permanent sections from the surgical specimen, a well encapsulated 3.0 x 2.0 x 1 cm nodule, also led us to suspect medullary carcinoma, but immunohistochemical staining for thyrocalcitonin, CEA, and thyroglobulin showed that it was a hyalinizing trabecular adenoma.

Adenoma↗
PubMed1989

Plasmacytoma of the pancreatic head.

Plasmacytomas of the pancreas are extremely rare. This is a report of a patient with plasmacytoma of the head of the pancreas who also had an extramedullary plasmacytoma of the epipharynx 19 months earlier. Computed tomographic (CT) scans revealed a multilobular homogeneous mass in the pancreas. Endoscopic biopsy of adjacent polypoid lesions in the duodenum allowed confirmation of the diagnosis.

Aged↗