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Biomedical subjects

J Chang

Publications and source records attributed to J Chang.

At least 541 records · Page 30Linked to original sources
PubMed1979

Percutaneous transluminal angioplasty with the Grüntzig balloon catheter. A review of 70 cases.

Percutaneous transluminal angioplasty has been used to treat lesions of the iliac, superficial femoral, and renal arterial systems in 70 patients. Overall initial success was achieved in 27/30 lesions, with 4/5 lesions documented to be patent for longer than two years. Although long-term follow-up is at present limited, the reduced cost and morbidity of this procedure are distinct advantages in appropriately selected patients. The close involvement of the vascular surgeon and a "team" approach are necessary. These preliminary results are part of a long-term study to evaluate the efficacy of transluminal angioplasty as well as to define factors that may be of predictive value in patient selection.

Arteriosclerosis↗
PubMed1979

Percutaneous transluminal angioplasty (PTA) with the Grüntzig balloon catheter: technical problems encountered in the first forty patients.

Forty patients have undergone percutaneous transluminal angioplasty (PTA) of the iliac or femoral-popliteal system with the Grüntzig balloon catheter. Technical problems ahve included experience with difficult antegrade puncture, production of intimal flaps, and loss of collateral vessels, as well as the need to develop an approach for recanalization of obstructions and for use of the balloon. Since problems in these areas may jeopardize the success of the procedure, they have been elucidated with some discussion of prevention. Preliminary results on the success of the procedure are included.

Anticoagulants↗
PubMed1979

Advances in the management of bile duct obstruction: percutaneous transhepatic cholangiography and endoscopic retrograde cholangiopancreatography.

Jaundice can be diagnosed anatomically and frequently histopathologically without laparotomy by radiologic and endoscopic techniques, combined with biopsy or cytology. Benign and malignant causes of bile duct obstruction can be managed by endoscopic and radiologic methods with reduced morbidity and mortality, displacing abdominal operation for many entities. Even unresectable or inoperable lesions can be effectively palliated by these new techniques.

Biliary Tract Diseases↗
PubMed1979

Percutaneous transhepatic portal venography in the diagnosis and management of gastroesophageal varices.

Percutaneous transhepatic portal venography is a relatively safe method of obtaining both physiologic and morphologic information in patients with portal hypertension. Precise "road mapping" is performed, as well as measurement of free portal pressure. Additionally, transcatheter obliteration of gastroesophageal varices may produce effective cessation of hemorrhage in patients bleeding from this site, as was done on an emergency basis after failure of intra-arterial vasopressin infusion.

Adult↗
PubMed1979

Percutaneous transluminal angioplasty with the Grüntzig balloon catheter.

The results of an ongoing five-year study of percutaneous transluminal angioplasty for the treatment of peripheral vascular disease are presented. A balloon catheter was used for iliac and superficial femoral and popliteal artery dilatation. Forty out of 43 procedures performed were considered to have initial success, with iliac angioplasty showing a greater success rate (96%) than superficial femoral angioplasty (90%). Complications requiring surgical intervention occurred in only 3 patients. Advantages of this technique include local anesthesia, early ambulation, reduced hospital stay, and reproducibility.

Catheterization↗
PubMed1979

Percutaneous transluminal angioplasty for treatment of renovascular hypertension.

Four patients with typical renovascular hypertension due to atherosclerotic stenosis (3 patients) and near occlusion (one patient) were treated with percutaneous transluminal angioplasty (PTA). Two patients had malignant hypertension by clinical standards. All had significant reduction in blood pressure following angioplasty, resulting in either a normotensive state, or management with significantly less antihypertensive medication. Patency and normal renin levels were achieved within two months in 2 patients. Clinical follow-up documented continued reduction in blood pressure. Advantages of the procedure include local anesthesia, relatively little discomfort, repeatability, and the fact that surgery is not precluded if angioplasty is unsuccessful.

Anesthesia, Local↗
PubMed1979

Spontaneous cholangiocarcinoma in a ring-tailed lemur (Lemur catta).

A cholangiocarcinoma in the liver with metastasis to the regional lymph nodes was found in a male ring-tailed lemur (Lemur catta). The liver was partially replaced by a gray-white, coarsely lobulated mass. Microscopically, the tumor consisted of well circumscribed lobules of anaplastic, low cuboidal cells occasionally arranged in duct-like structures. The tumor did not involve the gallbladder.

Adenoma, Bile Duct↗
PubMed1978

Squamous cell carcinoma of the renal pelvis presenting with hypercalcemia.

A case of hypercalcemia associated with documented squamous cell carcinoma of the renal pelvis without bony metastasis is reported. Pseudohyperparathyroidism was suspected strongly because of the radioimmunoassay values of parathormone. This was confirmed by the prompt decrease of serum calcium after removal of the neoplasm. The radiologic findings were non-specific.

Aged↗
PubMed1978

The analytic basis for the use of platelet estimates from peripheral blood smears. Laboratory and clinical applications.

Estimation of the platelet count from examination of peripheral blood smears is a widely practiced procedure, but statistical validity to judge the accuracy of the technic has been lacking. More than 400 patients' platelet estimates and counts were analyzed to develop a simple working formula to permit a reasonably accurate platelet estimate. Smear-to-smear and technician-to-technician variabilities were defined, and the influences of different microscopes on the platelet estimates were demonstrated. Platelet estimates can be used as a rapid, convenient measurement suitable for providing useful information for clinical judgement of a patient's platelet status providing that the method's limitations are recognized.

Blood Cell Count↗
PubMed1978

Transcatheter gelfoam embolization of posttraumatic bleeding pseudoaneurysms.

Diagnostic angiography combined with transcatheter therapeutic embolization is a simple and effective means of treating complex clinical situations associated with posttraumatic hemorrhage. Bleeding pseudoaneurysms, even when large, can be readily managed by this combined modality with resultant decrease in morbidity and hospital stay. Five patients with posttraumatic pseudoaneurysms are presented. All five were treated by transcatheter therapeutic embolization with Gelfoam. Of these five cases, three involved extremities, one involved the retroperitoneal space, and the last was of renal origin. Two of the five cases still required surgical intervention after initial successful therapeutic embolization, one for recurrent bleeding from collaterals and the other for evacuation of a massive pseudoaneurysm which was causing distraction of fracture fragments. The early use of angiography in suspected cases of posttraumatic hemorrhage, together with careful evaluation of potential collateral supply, is stressed. The use of transcatheter therapeutic embolization in the extremities as presented here is yet another example of the ever-broadening applicability of this technique.

Adult↗
PubMed1978

Transcatheter arterial embolization of a traumatic lumbar artery false aneurysm.

The case of a false aneurysm of a lumbar artery secondary to penetrating trauma is presented. Problems of diagnosis are outlined, emphasizing the value of ultrasound, computerized tomography, and angiography. The early use of angiography is strongly advocated in cases of suspected post-traumatic bleeding. The use and value of therapeutic transcatheter embolization is discussed.

Abdominal Muscles↗
PubMed1977

Aortic stenosis: echocardiographic cusp separation and surgical description of aortic valve in 22 patients.

Diminished echocardiographic aortic cusp separation is used as one indicator of the severity of aortic stenosis. To test the validity of this index, 22 patients--12 (55 percent) with isolated aortic valve disease and 10 (45 percent) with aortic stenosis associated with mitral or coronary artery disease--underwent M mode echocardiographic examination before aortic valve replacement. Tracings of diagnostic quality were obtained without difficulty from all 22 patients. Cardiac catheterization was performed in 21 patients. Echocardiographic cusp separation was measured from the apparent mid-systolic orifice and from the outer periphery of the anterior cusp to the outer periphery of the posterior cusp (maximal peripheral cusp separation). Mid-systolic cusp separation varied in nearly every patient, depending on the angle of leaflet presentation to the ultrasonic beam. Maximal peripheral cusp separation measured 16 mm in 18 of 22 patients (82 percent); it indicated neither the severity of the aortic stenosis as documented with cardiac catheterization nor the mobility of the cusps seen at operation. The surgical and echocardiographic descriptions of leaflet and aortic root calcification were similar. In situ examination of aortic cusp separation indicated that diseased aortic valves are not comparable with normal valves or valves with uncomplicated congenital obstruction. The aortic leaflets were curled, fused, calcified and deformed from their natural state of coaptation. Abnormal thickening and limited or eccentric mobility of the aortic leaflets were useful indicators of the cause of valve disease, but cusp deformity secondary to aortic stenosis invalidated mid-systolic cusp separation and maximal peripheral cusp separation as indicators of the severity of aortic stenosis.

Adult↗
PubMed1977

Screening for breast cancer.

Mammography is of real assistance to the surgeon in evaluating breast problems not associated with a breast mass. Use of mammography in the detection of early breast cancer in breast demonstration projects has brought forth the time honored value judgement of benefit vs risk. This report introduces an additional aspect in the consideration of benefit vs risk, the interval cancer. From the demonstration project at KUMC, 326 biopsies were performed and 65 proved to be cancer. However, 24 additional women developed cancer before their next recommended screening date. This reduces the accuracy of mammography and physical examination by trained nurses in screening for breast cancer to 73%.

Adult↗
PubMed1977

Inhibition by glucocorticoids of prostaglandin release from adipose tissue in vitro.

1 When rabbit chopped adipose tissue was incubated with a lipolytic agent (adrenocorticotrophic hormone, ACTH1-24, 0.1 microng/ml) in Krebs solution, prostaglandin E2 was formed in the tissue and about the same amount was found in the medium. 2 In the presence of indomethacin (1 microng/ml) the appearance of prostaglandin E2 was almost abolished both in the tissue and in the medium. 3 When the incubation was carried out in the presence of hydrocortisone or betamethasone (1-10 microng)ml) the concentration of prostaglandin E2 leaking or carried into the medium was significantly reduced, whereas that remaining in the tissue was significantly increased. This action of the steroids was not reversed by increasing substrate (arachidonic acid) concentration in the medium. 4 The steroids did not affect lipolysis, nor did they influence prostaglandin metabolism since such activity was not detectable in the adipose tissue. 5 Anti-inflammatory steroids therefore did not reduce prostaglandin formation but increased the tissue/medium ratio, which supports the view that they inhibit the release of prostaglandins after these have been synthesized.

Adipose Tissue↗
PubMed1977

Co-existent chronic lymphatic leukaemia with polycythaemia vera.

A patient presenting with chronic lymphocytic leukaemia and iron deficiency anaemia who, following oral iron therapy, developed the clinical and pathological features of polycythaemia vera is reported. The relationship between these two diseases when co-existing is discussed.

Aged↗