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K Y Tzen

Publications and source records attributed to K Y Tzen.

At least 19 recordsLinked to original sources
PubMed1992

Measurement of separate glomerular filtration rate by means of 99mTc-DTPA.

We detected the separate glomerular filtration rate (SGFR) with 99mTc-DTPA in patients on the nephrology ward since 1987. There were 40 patients, 19 males and 21 females. Their age ranged from 15 to 79 years old, with a mean +/- 1SD of 44 +/- 17 years old. They all received a SGFR examination and one or two creatinine clearance (Ccr) examinations during hospitalization. The Ccr values ranged from 4.6 to 141.5ml/min, and the mean +/- 1SD was 68.1 +/- 37.9ml/min. The total GFR value by the SGFR method was 1 to 142ml/min, with a mean of 78.9 +/- 39.4ml/min. The correlation coefficient of Ccr and SGFR was r = 0.81 (p = 0.0001). All 16 patients who had a SGFR less than 40% of the total GFR had specific clinical problems in that particular kidney. We concluded that 99mTc-DTPA renography was a correct and rapid method to check GFR, and may be another choice in addition to the traditional Ccr measurement. It was also a useful method for the diagnosis of disease in one kidney.

Adolescent↗
PubMed1992

Localization of obscure gastrointestinal bleeding by technetium 99m-labeled red blood cell scintigraphy.

When a bleeding source from the gastrointestinal (GI) tract cannot be identified with conventional diagnostic studies, it is known as GI bleeding of an obscure origin. In the past three years, in vivo Technetium 99m-labeled red blood cell scintigraphy (RBC scan) has been added to our armamentarium for the diagnosis of obscure GI bleeding. Out of a total of 26 cases, the bleeders could be detected in 12 or 46.2% by RBC scan. The time required ranged from 15 minutes to 24 hours (median, one hour). In 14 patients with active bleeding during the scan period, 11 had positive scans (sensitivity, 78.6%). In 12 patients with inactive bleeding, 11 had negative scans (specificity, 91.7%). Angiography was conducted in nine cases, with all showing negative findings; however, six of them had a positive focus by RBC scan. Laparotomy was performed in seven scan-positive patients, and in three scan-negative patients because of a positive Meckel's scan (two cases) or recurrent bleeding (one case). Of the 12 scan-positive patients, incorrect localization was noted in two patients due to rapid transit of the labeled RBC in the small bowel. False localization could be prevented by shortening the sequential imaging interval. It is concluded that an RBC scan is a very sensitive and safe tool for detection of GI bleeding of an intermittent nature, because the bleeder can be monitored for 24 hours after a single injection. It can be used as a preangiographic screening test and to guide the surgeon in surgical planning or decision-making.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Using 131I-MIBG and 99mTc-MDP bone scan for localization of rare extra-adrenal pheochromocytomas: report of 2 cases].

It is difficult, but important, to diagnose extra-adrenal pheochromocytomas before surgery. Failure to recognize the existence and nature of an extra-adrenal pheochromocytoma can cause life-threatening problems even in a minor surgical operation. We present two rare cases of extra-adrenal pheochromocytomas which were detected by 131I-MIBG scintigraphy. One of them was intrapericardial, and the other was a vesical pheochromocytoma. We used a combined 99mTc-MDP bone scan and 131I-MIBG scintigraphy to locate the pheochromocytomas. Both cases of extra-adrenal pheochromocytoma were correctly diagnosed preoperatively and successfully resected in the subsequent operations.

3-Iodobenzylguanidine↗
PubMed1991

[Serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA 19-9) values in patients with pancreatic cancer or pancreatitis].

For evaluating the diagnostic rate of serum CA19-9 and carcinoembryonic antigen (CEA) in pancreatic malignancies and pancreatitis, 22 patients with pancreatic malignancy, 27 patients with acute pancreatitis and 7 patients with chronic pancreatitis were included in this prospective study. The normal values of CEA and CA19-9 were 2.0 ng/ml and 36 U/ml respectively in 10 healthy males and 11 healthy females. The positive rates of CEA (greater than 2.5 ng/ml) in pancreatic malignancy, acute pancreatitis and chronic pancreatitis were 50%, 47% and 38%, respectively. On the other hand, the positive rates of CA19-9 (greater than 37U/ml) in pancreatic malignancy, acute pancreatitis and chronic pancreatitis were 82%, 26% and 23%, respectively. In diagnosis of pancreatic malignancy, the positive rate of CA19-9 is higher than that of CEA (82% vs 50%), and CA19-9 has a sensitivity significantly higher in differentiating from pancreatitis than CEA. In 7 cases of pancreatic malignancy with metastasis (liver or peritoneum), all had abnormally high serum CA19-9 (greater than 195 U/ml), 6 of 7 had CA19-9 levels over 1000 U/ml. In the view of CEA, 6 of 7 had serum CEA over 5 ng/ml, one patient with peritoneal metastasis had normal CEA level. In this study, we conclude that the diagnostic rate of CA19-9 in pancreatic malignancies is better than that of CEA.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1990

Using a computerized method to measure 99mTc pertechnetate uptake for the assessment of thyroid function: a clinical validation.

This retrospective study evaluated thyroid function by the 99mTc pertechnetate uptake ratio, using computer software designed in our laboratory. We expected that this measurement could be a precise and accurate index. The following studies were performed on 187 patients: (1) 24-hour radioimmunoassay of serum thyroid hormones, including serum thyroxine, free T4, triiodothyronine, thyrotropin concentrations, and T3 resin uptake; (2) 99mTc pertechnetate thyroid imaging and uptake measurement; and (3) 24-hour 131I thyroid uptake. Based on the clinical findings and the results from the predescribed laboratory tests, we found that: (1) the mean value of the 99mTc pertechnetate thyroid uptake ratio in the euthyroid groups was 2.77 +/- 1.77% (mean +/- SD); (2) the correlation coefficient between the 99mTc pertechnetate thyroid uptakes and the 24-hour 131I uptakes of the euthyroid patients was 0.71; and (3) hyperthyroidism could be distinguished from euthyroid condition easily. By setting the upper limit of euthyroid 99mTc pertechnetate thyroid uptake at 6.31%, the diagnostic sensitivity was 92.9%, specificity 96.1%, and accuracy 95.6% in separating hyperthyroid from euthyroid patients. These values were similar to those determined by the 24-hour 131I uptake measurements. Thus, thyroid function can be evaluated simultaneously with a routine 99mTc pertechnetate thyroid scan. Both the patient time and cost can be saved with this method, since the measurement takes only 25 minutes. Decreased radiation exposure is another advantage of this method over the traditional 131I uptake measurement.

Adolescent↗
PubMed1990

Bone changes in hyperthyroidism--a preliminary study.

Thyrotoxicosis may cause osteopenia and lead to increased risk of fractures. From July 1988 to March 1989, 88 hyperthyroid patients and 65 age, sex matched normal controls were enrolled for lumbar spine bone mineral density (BMD) study. Significantly lower BMD values can be found in premenopausal hyperthyroid women (1.233 gm/cm2 vs 1.317 gm/cm2, p less than p less than 0.05). In the group of thyrotoxicosis, no linear correlation can be found between BMD and the degree of hyperthyroidism (N = 84, r = 0.01 and N = 74, r = 0.054 as comparing BMD to T4 and T3, respectively). After treatment with antithyroid drugs (ATD) for 3 months, BMD did not change significantly (1.258 gm/cm2 vs 1.242 gm/cm2, p = 0.02) in the hyperthyroid patients. Therefore, premenopausal hyperthyroid women have lower BMD than premenopausal euthyroid women. The treatment of hyperthyroidism after 3 months' course did not increase lumbar spine BMD.

Adult↗
PubMed1989

Quality assurance and precision of dual photon absorptiometry in bone mineral measurement.

Dual photon absorptiometry (DPA) has evolved as a powerful technique in measuring bone mineral density (BMD) to assess osteoporosis and metabolic bone diseases in recent years. We introduced the first installation of DPA instrument into this country in Aug. 1987. Since the comparison among longitudinal BMD values influences the diagnosis, monitoring and medical decision-making, high precision of the system performance and strict quality assurance program are prerequisite for judgment of the difference between two successive measurements. However, the automation and black-box software design of the instrument make users gain very little knowledge how the instruments acquire the long-term system reliability. The first part of this study was designed to establish a standardized procedure to evaluate the long-term quality of the DPA instrument. Our instrument was proved to have stable sensitivity, resolution, accuracy and reproducibility in the four months of study. Three subjects with different BMD levels were scanned to evaluate the intraobserver and interobserver errors in BMD analysis expected in our laboratory (2.2 and 1.6% at 95% confidence level, respectively). The results indicated that reanalyzing the same scan by either of the two observers would produce a BMD precision error within 2.2% at a 95% confidence level. Serial scans of 7 normal volunteers within five weeks were then conducted to evaluate the overall precision of the BMD measurements. Our findings indicated that two scans would be considered as having a real BMD change if they differ by more than 3.3% at a 95% confidence level. There are at least five sets of DPA instruments that have been installed in Taiwan presently.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[First pass radionuclide angiography in the measurement of the left ventricular ejection fraction--assessment of the accuracy of a new method].

This study was designed to validate a modified computer program in evaluating the left ventricular ejection fraction (LVEF) by first pass radionuclide cardioangiography. This program was modified by us from the pulmonary background subtraction method postulated by Gal et al. Another three programs supplied by the computer company were included in the study to compare the accuracy among these program algorithms. From the results of 97 patients undergoing first pass and gated equilibrium cardiac blood pool studies, we found that the measured ejection fractions by these four programs were all correlated well with those by the equilibrium gated cardiac program (r = 0.81-0.86). The latter was already confirmed and verified in a previously published work using a Vanderbilt dynamic cardiac phantom. Except for the LVEF values obtained from our modified program, all values obtained from the other three programs were significantly lower than those obtained by the verified equilibrium program. However, the results obtained from our designed program correlated well with those obtained from the equilibrium method. Furthermore, none of the patient's raw data was rejected by this modified program.

Humans↗
PubMed1985

Radionuclide venography in Budd-Chiari syndrome with intrahepatic vena-caval obstruction.

Radionuclide imaging of the inferior vena cava (RIVC) was performed by injecting [99mTc] phytate into a dorsal pedal vein, as an initial diagnostic procedure for eight patients with clinical features of Budd-Chiari syndrome. In five of them, membranous occlusion of the inferior vena cava (IVC) was proved by contrast venography and subsequent surgery. The other three patients, with histologically verified hepatocellular carcinoma, were proved to have tumor-induced narrowing or occlusion of the IVC by contrast venography. The RIVC findings include a sharply truncated inferior vena cava with marked hand-up of activity, extensive collaterals, and delayed visualization of the heart. Our results indicate that RIVC is as accurate and specific as contrast venography, by demonstrating the occlusion of the IVC and collateral circulation from the functional aspect. This simple and noninvasive method could therefore be used as a first-line test in patients with unexplained edema, ascites, superficial abdominal venous collaterals, and even in patients with hepatocellular carcinoma, for the detection of obstruction in the inferior vena cava.

Budd-Chiari Syndrome↗