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K Yamao

Publications and source records attributed to K Yamao.

At least 55 records · Page 3Linked to original sources
PubMed1993

[A case involving coronary dissection caused after PTCA that was observed with intravascular echocardiography].

We encountered a case that was observed on coronary angiography (CAG) during coronary dissection after coronary angioplasty (PTCA) in which the dissected cavity disappeared on CAG but thrombolytic obstruction in the dissected cavity could be observed by intravascular echocardiography (IVUS). A 67-year-old woman was admitted with a diagnosis of acute myocardial infarction with ST elevation when experiencing chest pain. PTCR was performed for obstruction of the left circumflex artery (LCX) and the stenosis was improved to 90 percent. One month later PTCA was performed on an obstruction lesion in LCX and the feature of the dissected section at the same site was observed by CAG after PTCA. CAG showed that the dissected cavity had disappeared a year and a half later, but IVUS indicated thrombolytic obstruction in the dissected cavity.

Aged↗
PubMed1992

[Endoscopic ultrasonographic study of gastric ulcer treated with proton pump inhibitor].

We examined 70 cases of gastric ulcer by endoscopic ultrasonography. Of these, 18 cases were treated with proton pump inhibitor (PPI), another cases were treated with histamine H2 receptor antagonist or mucosal protective drugs. The Endoscopic cumulative healing rate at the eighth week was 71.4% in all gastric ulcers. On the other hand, all of gastric ulcers treated with PPI were healed within eight weeks endoscopically. Gastric ulcers which were revealed ultrasonographically to be refractory with were healed by PPI therapy. The length of the ulcer echo in gastric ulcers treated with PPI was shorter than that in gastric ulcer treated by other drugs. In spite of endoscopic scar findings, a wide ulcer echo was observed in some cases.

Adenosine Triphosphatases↗
PubMed1992

[Extracorporeal shock wave lithotripsy (ESWL) for common bile duct stones].

We treated twenty-three patients with common bile duct stones (12 female, 11 male, mean age: 67.1 years) by Extracorporeal Shock Wave Lithotripsy (ESWL). The stones were focused by ultrasonic or choledochographic localization. The twenty-three patients received 53 ESWL treatments consisting of mean 2357 shocks per treatment at mean 18 kV. We performed ESWL in five cases with endoscopically unextractable common bile duct stones after endoscopic sphincterotomy (EST). In these cases, ESWL permitted stone disintegration and successful endoscopic extraction of the fragments. We performed ESWL in eighteen cases with common bile duct stones without EST. In fifteen of the eighteen cases (83%), fragmentation was achieved. The stone fragments were spontaneously discharged in ten cases (56%) after a median of 4 days following ESWL. In five cases, adjutant endoscopic procedures were performed. The complete fragmentation and the clearance rate for stones of diameter of less than 10 mm were higher than that for stones of diameter of more than 11 mm. In the cases with the stones of diameter of more than 10 mm, there is a very strong possibility that complete clearance is achieved by ESWL alone. No correlation was obtained for the effective results according to pretreatment number of stones. In eight of thirteen cases (62%) with gall bladder stones, complete clearance was achieved without EST. ESWL without EST can be thought as a rational treatment for preserving the function of papilla of Vater in the case of cholecysto-choledocholithiasis.

Aged↗
PubMed1992

[Comparative study of extracorporeal shock wave lithotripsy (ESWL) between spark gap system and piezoelectric system].

We have analyzed the results of the treatment given on 170 cases of cholecystolithiasis, using two different systems of ESWL: Spark Gap System (hereinafter SGS) and Piezoelectric System (hereinafter PES). 1) In the total cases, there were no significant differences in the fragmentation rate between the two systems. PES was, however, superior to SGS in terms of the complete stone free rate. On the other hand, SGS was superior to PES in terms of the average fragmentation rate. 2) We have classified cholecystolithiasis into 4 groups, combining CT and US. PES showed superiority in the ESWL Group 1 (seeming Pure Cholesterol Stone) and Group 2 (seemingly Mixed Stone) in terms of stone free rate. SGS showed superiority in ESWL Group 3 (seemingly Combination Stone) and Group 4 (seemingly Pigment Stone) in terms of fragmentation effect. 3) We have gained good results from both of the system according to Munich Criteria Modified. 4) Concerning the failures of fragmentation and insufficient stone free, further study shall be required to determine whether fragmentation should be repeated, the case should be handled as "beyond adaptability", or the two-system-combined therapy should be applied.

Adult↗
PubMed1991

Mucin-producing tumor of the pancreas.

A new pancreatic tumor, called mucin-producing tumor, has received great attention in Japan. These tumors are found inside the pancreatic duct and produce large quantities of copious mucus. The authors examined 22 cases of these tumors histologically and histochemically. In 12 malignant cases, the tumors inside the ducts consisted of cancerous lesions over small areas along with papillary or atypical hyperplasia. Tumors in ten benign cases mainly consisted of papillary hyperplasia. Except for three patients with carcinoma in situ, cancerous tumors infiltrated the pancreatic parenchyma and, in some cases, were observed invading the bile duct or duodenum. A mucous histochemical study showed evidence of sialomucin in malignant cases; neutral mucin was dominant in benign cases. Characteristics of this disease were also compared with 13 cases of mucinous cystic neoplasm. From the results, it was concluded that these two diseases can be classified into the same conceptual category.

Aged↗
PubMed1991

Value of endoscopic ultrasonography in the detection of anomalous connections of the pancreatobiliary duct.

Endoscopic ultrasonography (EUS) was evaluated in the detection of anomalous connection of the pancreatobiliary duct (ACPBD), which is known to cause cholangitis and has been found to be associated with cholangiocarcinoma. Fourteen patients with ACPBD were examined preoperatively by EUS in addition to ERCP and/or PTC. In all cases, the anomalous connections between the biliary and pancreatic duct were demonstrated to be located outside the proper muscle of the duodenal wall and within the pancreatic parenchyma. EUS classification of ACPBD corresponded well with the findings obtained by retrograde ductal opacification on ERCP and PTC. Biliary malignancy complicating ACPBD was detected correctly by EUS in two patients. In contrast, no connections between biliary and pancreatic ducts were found by EUS in 13 normal controls. It is concluded that EUS is highly sensitive in detecting ductal anomaly in ACPBD. Further studies will show if EUS can replace ERCP in the diagnosis of ACPBD.

Adult↗
PubMed1990

[A study on the new measurement of gastric lesions with an electronic endoscope].

We carried out measurement of gastric lesions in the inner surface of the stomach with a measuring system, which is composed of a stereo endoscope and a personal computer. Basically, the length on a flat board from 10 mm to 50 mm was measured by varying the distance between the lens and the board and the angles of the endoscope at first. The error of the measurement was less than 8.5%. Secondly, ten physicians of our clinic attempted the measurement of the pasted discs on the inner wall of a stomach model with the endoscope. The average measurement error and the average time required for endoscopy became more better using the newly developed system than a measuring rod. Clinically, we measured the length of stomach lesion and of normal mucosa in six patients and compared the values obtained with those of resected fresh specimens. The length of stomach lesions could be measured more accurately than that of normal mucosa of stomach. From our observations, it can be said that this system is as available as the basic examination procedures in use at present and worth using in clinical procedure for it's high reliability.

Electrodiagnosis↗
PubMed1989

Percutaneous cholecystoscopy.

Since 1981, we have been conducting research on percutaneous transhepatic cholecystoscopy through the sinus tract of percutaneous cholecystostomy and this method has been employed in 72 patients with gallbladder diseases. We have already reported on percutaneous transhepatic cholecystoscopy and its usefulness for the diagnosis of early gallbladder carcinoma. Histological diagnosis was possible on the basis of cholecystoscopic biopsies in all 21 patients with gallbladder carcinoma, including eight patients with early carcinoma. Percutaneous cholecystoscopy is a reliable method for making the differential diagnosis between carcinoma and polypoid lesions of the gallbladder, and the diagnosis of cancer extension on the mucosa to the cystic duct. This method is recommended as a further and final step for the early diagnosis of gallbladder carcinoma. We performed endoscopic lithotripsy with the Nd:YAG laser or electrohydraulic lithotripter, and treated 21 patients with cholecystolithiasis. We report here on the results and features of this method as a nonsurgical treatment for cholecystolithiasis.

Adenoma↗
PubMed1989

Age and sex-dependent changes in serum amylase in an apparently healthy population.

In order to determine whether changes in serum amylase are age- or sex-dependent, we evaluated age- and sex-stratified serum amylase values in subjects who were proven to be healthy by a precise preventive health examination. Results showed that serum amylase increased as age progressed, except in the 0- to 29-yr-old female group. Mean serum amylase was higher in females than in males. A previous study indicated that the etiology of the increase in amylase in elderly persons is due to a progressive decline in renal function with aging. The etiology of the sex difference, especially in the younger generation, requires further investigation. We should pay attention to the factor of age when we evaluate serum amylase.

Adolescent↗
PubMed1989

Cardiac response to upper gastrointestinal endoscopy.

In 54 subjects, cardiac function was investigated during upper gastrointestinal endoscopy with a Holter electrocardiorecorder. The heart rate of patients who were premedicated with an anticholinergic agent increased more than did that of patients who received no premedication. In the group who received no anticholinergic premedication, sinus tachycardia was evident during endoscopy, but the only clinically important change was in one patient who converted to atrial flutter from atrial fibrillation. The heart rate increased during endoscopy among patients undergoing the procedure for the first time, but it did not increase in the patients who had previously undergone endoscopy. These results show that endoscopy is a relatively safe examination from the view point of cardiac risk when performed without the administration of an anticholinergic agent, but that cardiac patients should be monitored carefully. The endoscopist should also take into consideration the psychological state of the examinees.

Adult↗
PubMed1988

Clinical efficacy of endoscopic injections of OK-432 in the treatment of gastric cancer.

A total of 48 patients with gastric cancer were randomly assigned to receive either endoscopic injections of OK-432 plus systemic treatment with intravenously administered 5-fluorouracil and intradermally injected OK-432 (group A) or systemic therapy alone (group B). Morphologic improvement occurred in 7 of the 22 patients in group A. In one patient the tumor mass disappeared completely. In group B morphologic improvement occurred in only 2 of the 26 patients. The survival rate throughout the 24-month period was significantly (P less than 0.01) higher in group A than in group B patients. Thus, local administration of OK-432 by endoscopic injection is effective and is recommended for the treatment of patients with advanced gastric cancer.

Administration, Oral↗
PubMed1988

Chronic alcohol abuse leads to gastric atrophy and decreased gastric secretory capacity: a histological and physiological study.

We performed morphological and physiological studies in 43 male patients with alcohol dependence (ALC) who had no other apparent lesions in the upper gastrointestinal tract except atrophic and erosive gastritis. A gastric secretory study in which tetragastrin was used as the stimulant revealed that acid and pepsin secretion was less in ALC patients than in hospital controls (p less than 0.001). Endoscopic biopsy specimens of gastric mucosa from ALC patients revealed that atrophy of the gastric mucosa advanced with age. A strong negative correlation was also found between the secretory capacity of the stomach and the degree of atrophy. Possibly, the interval between recurrent episodes of acute mucosal damage was too short to allow complete healing of mucosal lesions. Failure to regenerate denuded epithelium would result in a decrease in the gastric secretory area. Thus, chronic alcohol abuse seems to be an etiological factor in atrophic gastritis.

Adult↗
PubMed1988

Nonsurgical treatment of cholecystolithiasis with percutaneous transhepatic cholecystoscopy.

Early surgical intervention in acute cholecystitis is sometimes fatal to patients in the high-risk group. Since the technical development of ultrasonically guided puncture of the gallbladder, percutaneous transhepatic cholecystostomy has become a safer method for the treatment of acute cholecystitis. We have been developing percutaneous transhepatic cholecystoscopy procedures since 1981, and have used this method in 11 patients with cholecystolithiasis. In all cases, we were able to destroy the stones with the Nd-YAG laser, and remove the fragments with a basket catheter through the fistula. There were no severe complications from percutaneous transhepatic cholecystostomy or cholecystoscopy. This lithotomy technique is a safe and reliable nonsurgical technique for patients with cholecystolithiasis, especially the elderly high-risk group.

Aged↗
PubMed1987

Effect of omeprazole on gastric acid secretion in rat: evaluation of dose, duration of effect, and route of administration.

The effect of omeprazole on gastric acid output was studied in rats before and during stimulation by continuous administration of tetragastrin at 50 micrograms/kg-hour. From 5 to 20 mg/kg of omeprazole was given to animals intraperitoneally, perorally and intravenously from 2 to 24 hours before the gastric secretory study was started, and the respective effects on acid secretion were compared. In each administration group, 20 mg/kg of omeprazole was the most potent among the groups receiving 5, 10 or 20 mg/kg, when the drug was given 2 hours before the study. There were statistically significant differences between the control group given tetragastrin only and each of the groups given 20 mg/kg of omeprazole perorally, intraperitoneally and intravenously. There was no significant difference among the groups given 20 mg/kg of omeprazole intraperitoneally, intravenously and perorally. The effect of 20 mg/kg of omeprazole continued at least 24 hours after the agent was administered perorally.

Administration, Oral↗