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Biomedical subjects

K Sugano

Publications and source records attributed to K Sugano.

261 records · Page 15Linked to original sources

Catheter dislodgement of percutaneous transhepatic biliary drainage: identification of role of puncture sites and catheter sheath.

BACKGROUND: To identify the appropriate puncture points in the bile duct to avoid catheter dislodgement. METHODS: Percutaneous transhepatic biliary drainage catheters (n = 300) were placed in 242 patients. The frequency of dislodgement (complete dislodgement or bending of the catheter) was prospectively investigated. The puncture site of the bile duct was classified on the ultrasonographic findings as follows: Main-B3, main branch of the lateral inferior segment; peripheral-B3, peripheral branch of the lateral inferior segment; B2, lateral superior segment; left hepatic duct, proximal portion of the left hepatic duct; B8, anterior superior segment; B5, anterior inferior segment; B5 + 8, main bile duct of the anterior segment; B6, bile duct of posterior inferior segment; and right hepatic duct, proximal portion of the right hepatic duct. RESULTS: When a catheter without an outer sheath was used, catheter dislodgement in peripheral-B3 (2/11, 18%) was more common than in main-B3 (0/32, 0%; p < 0.05). In B5, catheter dislodgement (6/12, 50%) was more frequent than in B8 (3/20, 15%; p < 0.05) and in B6 (0/14, 0%; p < 0.005). When a catheter with an outer sheath was used, catheter dislodgement (2/207, 1%) was rare. CONCLUSION: Drainage from B5 and peripheral-B3 is associated with a high risk of dislodgement of the catheter. A catheter with an outer sheath was useful to prevent catheter dislodgement.

Adult↗

Hyperechoic lines as a sonographic confirmatory sign during percutaneous transhepatic biliary drainage.

BACKGROUND: In ultrasonically guided percutaneous transhepatic biliary drainage, we often can recognize hyperechoic lines at the tip of the needle when the duct is penetrated successfully. We evaluated the frequency of this phenomenon and analyzed whether it was a useful sign for confirming successful bile duct puncture. METHODS: In 65 patients with biliary tract diseases, 84 catheters were placed in the course of 108 attempts at puncture. Results of puncture and the presence of hyperechoic lines were investigated prospectively. RESULTS: When the ultrasonographic findings showed hyperechoic lines, successful puncture was significantly more frequent than when the findings did not show hyperechoic lines (53/55, 96%, vs. 31/59, 53%; p < 0.0001). When we judged the hyperechoic lines as the sign of successful puncture, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 63%, 93%, 96%, 48%, and 71%, respectively. CONCLUSION: Hyperechoic lines are a useful confirmatory sign of successful puncture. However, absence of these lines was not invariably associated with unsuccessful puncture.

Aged↗

Intraductal ultrasonography for evaluating the patency of biliary metallic stents: correlation with cholangioscopic findings.

BACKGROUND: This is the first study to correlate intraductal ultrasonography (IDUS) with cholangioscopy in evaluating the patency of biliary metallic stents. METHODS: The findings of IDUS (probe 2.0 mm in diameter and 20-MHz frequency) through a percutaneous transhepatic (n = 24) or transpapillary (n = 2) approach were retrospectively reviewed without other information. Criteria for IDUS are as follows: type 1, the inside of the stent is free; type 2, the inner edge is smooth; type 3, the inner edge is irregular; type 4, the inside of the stent is totally occupied; type 5, the solid echo is connected to the outside mass; type 2+D, a hypoechoic line is seen between the bile duct wall and the inside solid component and the inner edge of the bile duct wall is smooth; type 3+D, an irregular hypoechoic line is seen between the bile duct wall and the inside solid component. RESULTS: In the control group (n = 11), IDUS showed type 1 (n = 9) or type 2 (n = 2). In the occluded group (n = 15), when IDUS showed type 3 or 5, the patients (n = 5) required additional stents (n = 3), microwave coagulation of the tumor (n = 1), or transient external drainage (n = 1). When IDUS showed type 4 (n = 5), after washing, the findings changed to type 2+D (n = 4). When IDUS after washing showed a smooth inner edge (type 2+D), the patients were treated without additional stents more frequently than the other groups (eight of nine vs. two of six), a significant distinction (p < 0.05). CONCLUSION: IDUS is useful in assessing the patency of metallic stents. When the inside of the stent is totally occupied, however, examination after washing is necessary.

Aged↗

Utility and limitations of intraductal ultrasonography in distinguishing longitudinal cancer extension along the bile duct from inflammatory wall thickening.

BACKGROUND: We wanted to distinguish wall thickening caused by cancer extension from that caused by inflammation after placing a biliary catheter on intraductal ultrasonography (IDUS). METHODS: We studied 51 patients with biliary tract malignancies who had undergone placement of biliary drainage catheters before IDUS. IDUS was performed from a transhepatic (n = 34) or transpapillary (n = 17) route with a thin-caliber ultrasonic probe (2.0 mm in diameter, 20-MHz frequency). At the hepatic side of the tumor, the thickness, asymmetry, outer margin, inner margin, and internal echoes of the bile duct wall were reviewed prospectively and correlated with the histologic findings of the surgically resected specimens in all cases. RESULTS: When IDUS showed wall thickening in a semicircular fashion, notched outer margin, rigid inner margin, papillary inner margin, and heterogeneous internal echoes, each finding had a positive predictive value for diagnosing cancer extension (100%, 100%, 83%, 100%, and 90%, respectively). When these factors were used as the diagnostic criteria of cancer extension, IDUS accurately demonstrated suitable surgical margins in 76% of all patients and 71% of patients with bile duct carcinoma. CONCLUSION: Wall thickening in a semicircular fashion, notched outer margin, rigid or papillary inner margin, and heterogeneous internal echoes are specific for cancer extension. However, surgical margins can be inaccurately assessed in some patients.

Aged↗

Prediction of the histologic type of bile duct cancer by using intraductal ultrasonography.

BACKGROUND: Patients with papillary adenocarcinoma survive longer than do patients with other histologic types of bile duct tumors. We evaluated the usefulness of intraductal ultrasonography (IDUS) for predicting the histology. METHODS: Preoperative tumor assessment was performed by using IDUS through a percutaneous tract or the transpapillary route in 37 patients with extrahepatic bile duct cancer. In 30 of 37 patients, imaging results were compared prospectively with histologic findings in resected specimens. Probes 2.0 mm in diameter and 20 MHz in frequency were mainly used. When IDUS showed a "narrow-based polypoid pattern" or a "papillary surface pattern," the patients were judged as having papillary adenocarcinoma. RESULTS: The accuracy, sensitivity, and specificity of IDUS in predicting papillary adenocarcinoma were 90%, 89%, and 90%, respectively. When intraductal ultrasonography showed a papillary surface pattern or a narrow-based polypoid pattern, lymph node metastases and perineural invasion were rarely seen when compared with other patients with bile duct cancer (p < 0.05). CONCLUSION: IDUS is useful for assessing the histologic type of bile duct cancer.

Adenocarcinoma, Papillary↗

Localization of the histamine H(2) receptor, a target for antiulcer drugs, in gastric parietal cells.

BACKGROUND/AIMS: Histamine H(2) receptor antagonists are widely used for the treatment of peptic ulcer disorders. However, whether the H(2) receptor is present in parietal or immune cells in the lamina propria remains controversial. This study is designed to determine the H(2) receptor localization immunohistochemically using an antibody against the newly cloned mouse histamine H(2) receptor. METHODS: We cloned the mouse histamine H(2) receptor gene and generated a specific antipeptide antibody against the C terminus. Immunohistochemical studies were performed with this antibody and with a monoclonal antibody against H(+)/K(+) adenosine triphosphatase (ATPase). RESULTS: Histamine H(2) receptors were localized on the plasma membrane and on the cytoplasm just beneath the plasma membrane on the basolateral sides of gastric cells. Confocal microscopy of double-stained sections using the monoclonal antibody against H(+)/K(+) ATPase, a specific parietal cell marker, showed that histamine H(2) receptors colocalized with H(+)/K(+) ATPase. No specific histamine H(2) receptor immunoreactivities were observed in the submucosal regions. CONCLUSION: The H(2) receptor is localized in the gastric parietal cell.

Amino Acid Sequence↗

Hypophosphatasia in an adult: a case report.

In this rare case of adult hypophosphatasia, no radiological abnormalities of the skeletal system could be detected even by dual energy X-ray absorptiometry. Severe dental caries was the sole clinical manifestation, indicating this case as an "odontohypophosphatasia". The levels of serum osteocalcin were low, which may be a useful biochemical marker to diagnose hypophosphatasia. Southern blot analyses of the genomic DNA revealed no gross abnormalities. Thus, hypophosphatasia in this patient was presumed to be caused by point mutations or small deletions. In a review of previous reports, an increased incidence among women was found.

Alkaline Phosphatase↗

Diagnosis of pancreatic cancer by cytology and measurement of oncogene and tumor markers in pure pancreatic juice aspirated by endoscopy.

BACKGROUND/AIMS: Cytological examination of pancreatic juice is useful in the diagnosis of an occult cancer of the pancreas. The early diagnosis of pancreatic carcinoma using traditional radiographic or ultrasonographic methods is extremely difficult. METHODOLOGY: In order to detect an early pancreatic cancer, cytological examination, measurement of tumor marker, and detection of K-ras point mutation were performed using the samples of pure pancreatic juice aspirated endoscopically in patients who had symptoms or findings that suggested pancreatic disease. RESULTS: By routine ERP-cytology, positive cytologic results were obtained in 15 (4%) out of 359 patients without a mass. With the aid of intra-operative cytodiagnosis, all 15 occult neoplasms of the pancreas were successfully resected. One patient died from another disease without evidence of recurrence. However, the other patients were alive with no evidence of recurrence for an average of 5.5 years following surgery. The patients who had negative ERP-cytology results were observed, but no further cases of pancreatic cancer were found. The CEA levels in the pure pancreatic juice were significantly higher in patients with pancreatic cancer than in those with pancreatitis. K-ras point mutation at codon 12 was detected not only in cases of pancreatic cancer, but also in cases of chronic pancreatitis as well as control subjects. CONCLUSIONS: Cytological examination of pancreatic juice is useful in the diagnosis of an early and potentially curable in situ cancer of the pancreas. The CEA levels in the pure pancreatic juice provided useful information for differentiating the pancreatic cancer from chronic pancreatitis. K-ras point mutation at codon 12 in pancreatic juice was considered to be useful in identifying patients at high risk for the development of pancreatic cancer.

Aged↗