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C H Kao

Publications and source records attributed to C H Kao.

At least 19 recordsLinked to original sources
PubMed2006

Fever of unknown origin in Taiwan.

BACKGROUND: Fever of unknown origin (FUO) is a challenging problem worldwide. There was no prospective study of FUO in the past two decades in Taiwan. A prospective study was conducted. MATERIALS AND METHODS: The prospective study was undertaken from March 2001 to May 2002. All patients fulfilling the modified criteria for FUO, either admitted, referred or consulted in a medical center in southern Taiwan, were enrolled for analysis. RESULTS: A total of 94 cases met the criteria of FUO. The final diagnoses of FUO consisted of 54 infectious diseases (57.4%), 8 hematologic/neoplastic (8.5%), 7 noninfectious inflammatory (7.4%), 8 miscellaneous (8.5%) and 17 undiagnosed (18.1%) cases. The single most common cause of FUO was tuberculosis. Some infectious diseases, such as rickettsiosis and melioidosis, were rarely reported in western countries. Three patients with hemophagocytotic syndrome without ascertainable etiologies were present with FUO in this study. Between the patients with and those without a final diagnosis, the short-term survival (3 months) was compared by the Kaplan-Meier analysis, which revealed no difference. CONCLUSIONS: Mycobacteriosis is still the leading cause of FUO in Taiwan and it is important to identify this treatable disease from all causes of FUO. This study has showed geographical variation among the studies of FUO.

Adolescent↗
PubMed2005

Adjoint acceleration of Monte Carlo simulations using TORT/MCNP coupling approach: a case study on the shielding improvement for the cyclotron room of the Buddhist Tzu Chi General Hospital.

Full-scale Monte Carlo simulations of the cyclotron room of the Buddhist Tzu Chi General Hospital were carried out to improve the original inadequate maze design. Variance reduction techniques are indispensable in this study to facilitate the simulations for testing a variety of configurations of shielding modification. The TORT/MCNP manual coupling approach based on the Consistent Adjoint Driven Importance Sampling (CADIS) methodology has been used throughout this study. The CADIS utilises the source and transport biasing in a consistent manner. With this method, the computational efficiency was increased significantly by more than two orders of magnitude and the statistical convergence was also improved compared to the unbiased Monte Carlo run. This paper describes the shielding problem encountered, the procedure for coupling the TORT and MCNP codes to accelerate the calculations and the calculation results for the original and improved shielding designs. In order to verify the calculation results and seek additional accelerations, sensitivity studies on the space-dependent and energy-dependent parameters were also conducted.

Algorithms↗
PubMed2005

The refined shielding design for the cyclotron room of the Buddhist Tzu Chi General Hospital.

Full-scale Monte Carlo simulations of the cyclotron room of the Buddhist Tzu Chi General Hospital were carried out to improve the inadequate maze design. The double differential neutron source from the 18O(p,n)18F reaction was adopted for the calculation. The weight window variance reduction technique, where the weight window was set by applying the adjoint flux, has been implemented in the MCNP run to facilitate the calculation of the dose rates outside the cyclotron room. Dose rates including neutron and gamma-ray components were calculated for some maze shielding modifications.

Computer Simulation↗
PubMed2003

Evaluation of the effects of methylprednisolone pulse therapy in patients with systemic lupus erythematosus with brain involvement by Tc-99m HMPAO brain SPECT.

Methylprednisolone pulse therapy (MPT) was introduced to avoid life-threatening complications in patients with systemic lupus erythematosus (SLE) with brain manifestations; however, the efficacy of MPT in SLE patients with brain involvement is still uncertain and needs to be objectively evaluated. We enrolled 15 female SLE patients with neuropsychiatric manifestations in this study. All patients had normal brain MRI and abnormal brain HMPAO-SPECT findings. Follow-up HMPAO-SPECT studies were conducted 2 weeks after MPT. Serum levels of anticardiolipin antibodies (ACA) and anti-ribosomal P antibodies (anti-P) were measured before and after MPT. Before MPT, 7 patients were positive for ACA and 7 patients were positive for anti-P. After MPT, none of the 15 patients demonstrated positive serologic findings or neuropsychiatric manifestations. Based on the follow up brain HMPAO-SPECT images following MPT, 13 patients showed disappearance of the perfusion defects and 2 patients showed partial recovery of rCBF. Brain HMPAO-SPECT imaging is a logical and objective tool for measuring the effects of MPT in SLE patients with brain involvement by determining of changes in rCBF.

Adult↗
PubMed2003

Usefulness of thallium-201 muscle scan to investigate perfusion reserve in the lower limbs of patients with systemic lupus erythematusus.

Patients with systemic lupus erythematosus (SLE) may develop premature atherosclerosis, notably peripheral vascular disease presenting with intermittent claudication or gangrene. This study evaluates the usefulness of thallium-201 muscle perfusion scan (Tl-201 muscle scan) for investigating perfusion reserve in the lower limbs of 25 asymptomatic, female SLE patients without peripheral ischemia findings. The patients showed no evidence of peripheral arterial disease in history, physical examination, or Doppler ultrasonography. A control group consisted of 24 healthy, age-matched women. Each subject flexed her right foot maximally both dorsally and plantarly 60 times. In the middle of this exercise, 2 mCi of Tl-201 was injected intravenously. Three minutes after the injection, a posterior image of both calves was obtained using a gamma camera. Rectangular regions of interest were symmetrically drawn over both calves. The total count in the resting calf was subtracted from the total count in the exercising calf, and the percentage of increase, termed the perfusion reserve, was determined. A significant difference was found between the perfusion reserves of the SLE patients and control groups (75.3+/-8.9% and 99.6+/-9.0%, respectively, P <0.05). In conclusion, perfusion reserve in the lower limb muscles of SLE patients may be measured by Tl-201 muscle perfusion scan.

Adult↗
PubMed2003

Using 99mTc HMPAO brain SPECT to evaluate the effects of anticoagulant therapy on regional cerebral blood flow in primary antiphospholipid antibody syndrome patients with brain involvement-a preliminary report.

Technetium-99m hexamethylpropylene amine oxime ((99m)Tc HMPAO) brain single photon emission computed tomography (SPECT) was used to evaluate the effects of anticoagulant therapy (ACT) on regional cerebral blood flow (rCBF) in patients with primary antiphospholipid antibody syndrome (PAPS). Sixteen female PAPS patients with neuropsychiatric manifestations and hypoperfusion lesions demonstrated on initial (99m)Tc HMPAO brain SPECT images were enrolled in this study. Follow-up (99m)Tc HMPAO brain SPECT images were performed 1 month after ACT. Meanwhile, serum anticardiolipin antibodies (ACA) were measured before and after ACT. Before ACT, 14 (87.5%) patients had positive ACA. After ACT, all 16 PAPS patients showed decreased serologic findings, and their neuropsychiatric manifestations subsided. After ACT, 11 (68.8%) patients showed complete recovery of regional cerebral blood flow (rCBF) and five (31.2%) patients showed partial recovery in the follow-up (99m)Tc HMPAO brain SPECT images. This type of imaging is a logical and objective tool for measuring the effects of ACT in PAPS patients with brain involvement by determining changes in rCBF.

Adult↗
PubMed2003

Usefulness of Tc-99m ECD brain SPECT to evaluate the effects of methylprednisolone pulse therapy in lupus erythematosus with brain involvement: a preliminary report.

Methylprednisolone pulse therapy (MPT) was introduced to avoid life-threatening complications in systemic lupus erythematosus (SLE) with brain manifestations. However, its efficacy in SLE patients remains uncertain and needs to be objectively evaluated. In this study, technetium-99m ethyl cysteinate dimer (Tc-99m ECD) brain single photon emission computed tomography (SPECT) was used to detect regional cerebral blood flow (rCBF) in SLE patients with normal brain magnetic resonance imaging (MRI) findings. Twelve female SLE patients with neuropsychiatric symptoms were enrolled in this study. All patients had normal brain MRI and abnormal Tc-99m ECD brain SPECT findings. The Tc-99m ECD brain SPECT studies were performed 2 weeks after MPT. Pre- and post-MPT serum levels of anticardiolipin antibodies (ACA) and antiribosomal P antibodies (anti-P) were also measured. Before MPT, four patients had positive ACA and seven had positive anti-P. After MPT, all 12 patients demonstrated negative serologic findings and no neuropsychiatric symptoms. After MPT, ten patients showed complete recovery and two showed partial recovery of rCBF in the follow-up Tc-99m ECD brain SPECT images. This imaging is a logical and objective tool for measuring the effects of MPT in SLE patients with brain involvement by the determination of rCBF changes.

Adult↗
PubMed2003

Simultaneously evaluating the effects of one-week fluticasone propionate inhalation therapy on lung ventilation and permeability in children with asthma.

This study evaluated the effects of fluticasone propionate inhalation therapy on lung ventilation and alveolar permeability by quantitative Tc-99m DTPA radioaerosol inhalation lung scintigraphy in 15 children with asthma. Lung ventilation was evaluated as the distribution percentage (D%) of Tc-99m DTPA radioaerosols in the central, intermediate and peripheral regions of the right lung. Alveolar permeability was measured by the rate of Tc-99m DTPA radioaerosol clearance curve from the peripheral alveoli of the right lung and represented as slope. The D% and slopes were calculated before and after one-week inhalation therapy (100 microg fluticasone propionate two times daily for one-week) to evaluate the effects of inhalation therapy on lung ventilation and alveolar permeability. The preliminary results revealed statistically significantly improved lung ventilation but no significant change of alveolar permeability in the right lung after one-week fluticasone propionate inhalation therapy in children with asthma. We suggest that the widely available and noninvasive Tc-99m DTPA radioaerosol inhalation lung scintigraphy can simultaneously evaluate lung ventilation and alveolar permeability in one study and should contribute to any disorder involving both alveoli and airways.

Adolescent↗
PubMed2003

Usefulness of 99mTc ethyl cysteinate dimer brain SPECT to detect abnormal regional cerebral blood flow in patients with acute carbon monoxide poisoning.

99mTc ethyl cysteinate dimer (99mTc-ECD) brain single photon emission computed tomography (SPECT) was used to detect abnormal regional cerebral blood flow (rCBF) in patients with acute carbon monoxide (CO) poisoning. Ten patients with acute CO poisoning and no past histories of psychoneurological disorders were enrolled in this study. After oxygen treatment, all of the 10 patients were investigated using 99mTc-ECD brain SPECT and brain computed tomography (CT) scan. Brain CT scan findings were normal in all of the 10 patients. 99mTc-ECD brain SPECT showed the hypoperfusion lesions of the basal ganglia and brain cortex in five and seven patients, respectively. Only three of the 10 patients had normal 99mTc-ECD brain SPECT findings. This study suggests that, in comparison with brain CT scan, 99mTc-ECD brain SPECT is a better tool for the early detection of hypoperfusion brain lesions in acute CO poisoning in patients with normal brain CT findings.

Adolescent↗
PubMed2003

Usefulness of technetium-99m methoxyisobutylisonitrile liver single photon emission computed tomography to detect hepatocellular carcinoma.

Technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) has been shown to be useful in identifying several types of tumors, such as breast, lung and thyroid cancers. The usefulness of Tc-99m MIBI liver imaging in detecting hepatocellular carcinoma (HCC) is still controversial. In this study, 22 patients with HCC performed Tc-99m MIBI liver single photon emission computed tomography (SPECT). Twenty of 22 patients (90.9%) showed negative liver SPECT findings without significant Tc-99m MIBI uptake in HCC, and only 2 patients (9.1%) showed positive liver SPECT findings with significant Tc-99m MIBI uptake in HCC. In addition, no significant correlation between liver SPECT findings with sex, age, alpha feto-protein serum level, HCC differentiation, and virus hepatitis status was found. We concluded that Tc-99m MIBI liver SPECT is not a sensitive tool to detect HCC.

Adult↗
PubMed2002

Comparing whole body 18F-2-deoxyglucose positron emission tomography and technetium-99m methylene diphosphate bone scan to detect bone metastases in patients with renal cell carcinomas - a preliminary report.

PURPOSE: Conventional technetium-99m methylene diphosphate whole body bone scan (bone scan) has a high sensitivity but a poor specificity to detect bone metastases. However, positron emission tomography with 18F-2-deoxyglucose (FDG-PET) can offer superior spatial resolution and improved specificity. We have attempted to evaluate the usefulness of FDG-PET for detecting bone metastases in renal cell carcinomas (RCC) and to compare FDG-PET results with bone scan findings. METHODS: Eighteen patients were selected for this study with biopsy-proven RCC. They were suspected of having bone metastases and were undergoing bone scan and FDG-PET to detect bone metastases. The final diagnoses of bone metastases were established by operative, histopathological findings or clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/bone scan findings showing progressive and extensive widespread bone lesions. RESULTS: A total of 52 bone lesions including 40 metastatic and 12 benign bone lesions found on either FDG-PET or bone scan were evaluated. FDG-PET could accurately diagnose all 40 metastatic and 12 benign bone lesions. Bone scan could accurately diagnose only 31 metastatic bone lesions. Diagnostic sensitivity and accuracy of FDG-PET were 100% and 100%, respectively,and bone scan were 77.5% and 59.6%, respectively. CONCLUSIONS: Our data suggest that FDG-PET has a higher sensitivity and a better accuracy than that of bone scan to detect bone metastases in patients with RCC.

Aged↗
PubMed2002

Comparing whole body (18)F-2-deoxyglucose positron emission tomography and technetium-99m methylene diphosphonate bone scan to detect bone metastases in patients with breast cancer.

PURPOSE: At present, bone metastases are usually assessed using conventional technetium-99m methylene diphosphonate whole-body bone scan, which has a high sensitivity but a poor specificity. However, positron emission tomography with (18)F-2-deoxyglucose (FDG-PET) can offer superior spatial resolution and improved specificity. We attempted to evaluate the usefulness of FDG-PET for detecting bone metastases in breast cancer and to compare FDG-PET results with bone scan findings. PATIENTS: The study group comprised 48 patients with biopsy-proven breast cancer and suspected of having bone metastases who underwent bone scan and FDG-PET to detect the bone metastases. The final diagnosis of bone metastases was established by operative, histopathological findings or during a clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/bone scan findings showing progressive widespread bone lesions. RESULTS: A total of 127 bone lesions including 105 metastatic and 22 benign bone lesions found by either FDG-PET or bone scan were evaluated. Using FDG-PET, 100 metastatic and 20 benign bone lesions were accurately diagnosed, and using bone scan 98 metastatic and 2 benign bone lesions were accurately diagnosed. The diagnostic sensitivity and accuracy of FDG-PET were 95.2% and 94.5%, and of bone scan were 93.3% and 78.7%, respectively. CONCLUSIONS: Our findings suggest that FDG-PET shows a similar sensitivity and a better accuracy than bone scan for detecting bone metastases in patients with breast cancer.

Adult↗
PubMed2002

Detection of recurrent nasopharyngeal carcinomas with positron emission tomography using 18-fluoro-2-deoxyglucose in patients with indeterminate magnetic resonance imaging findings after radiotherapy.

PURPOSE: The aim of this study was to evaluate the effectiveness of positron emission tomography (PET) using 18-fluoro-2-deoxyglucose (FDG) to detect recurrent nasopharyngeal carcinomas (NPC) when magnetic resonance imaging (MRI) findings are indeterminate. PATIENTS AND METHODS: After radiotherapy, 28 NPC patients with indeterminate MRI findings were included. MRI, FDG-PET, and biopsy were performed at least 4 months after radiotherapy and within 1 week. The final results were based on histopathologic findings and a clinical follow-up of at least 6 months. RESULTS: For detecting recurrent NPC in indeterminate MRI findings, the sensitivity, specificity and accuracy of FDG-PET were 100.0%, 92.9% and 96.4%, respectively. CONCLUSIONS: Based on these results, we can recommend FDG-PET for detecting recurrent NPC when MRI findings are indeterminate.

Adult↗
PubMed2002

Detection of cervical lymph node metastases in nasopharyngeal carcinomas: comparison between technetium-99m methoxyisobutylisonitrile single photon emission computed tomography and magnetic resonance imaging.

We compared the effectiveness technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) of head and neck in evaluating cervical lymph node (LN) metastasis in nasopharyngeal carcinomas (NPC). Forty NPC patients with cervical LN metastases confirmed histopathologically underwent Te-99m MIBI SPECT and MRI of the head and neck to evaluate cervical LN metastases. For 16 LN lesions with discordant results between Tc-99m MIBI SPECT and MRI, Tc-99m MIBI SPECT could correctly detect 1 metastatic and 10 benign LN lesions as well as MRI could correctly detect 3 metastatic and 2 benign LN lesions. Agreement positive results of Tc-99m MIBI SPECT and MRI could correctly detect all of the remaining 24 metastatic LN lesions. Tc-99m MIBI SPECT has a better specificity but a lower sensitivity for detecting cervical LN metastases in NPC when compared with MRI. The combined use of Tc-99m MIBI SPECT and MRI could increase the accuracy compared with the single use of either Te-99m MIBI SPECT or MRI to detect cervical LN metastases in NPC.

Adult↗
PubMed2002

Comparing whole body 18F-2-deoxyglucose positron emission tomography and technetium-99m methylene diophosphate bone scan to detect bone metastases in patients with non-small cell lung cancer.

Despite advances in morphological imaging, some patients with non-small cell lung cancer (NSCLC) are found to have non-resectable disease at surgery or die of recurrence within a year of surgery. At present, metastatic bone involvement is usually assessed using conventional technetium-99m methylene diophosphate (Tc-99m MDP) whole body bone scan (bone scan), which has a high sensitivity but a poor specificity. We have attempted to evaluate the usefulness of whole body positron emission tomography with 18F-2-deoxyglucose (FDG-PET) for the detection of malignant bone metastases of NSCLC, and to compare FDG-PET results with Bone Scan findings. Forty-eight patients with biopsy-proven NSCLC and suspected to have stage IV disease underwent whole body bone scan and FDG-PET to detect bone metastases. The final diagnoses of bone metastases were established by operative, histopathological findings or clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/Tc-99m MDP bone scan findings showing progressively and extensively widespread bone lesions. A total of 138 bone lesions found on either FDG-PET or Tc-99m MDP bone scan were evaluated. Among the 106 metastatic and 32 benign bone lesions, FDG-PET and Tc-99m MDP bone scan could accurately diagnose 99 and 98, as well as 30 and 2 metastatic and benign bone lesions, respectively. Diagnostic sensitivity and accuracy of FDG-PET and Tc-99m MDP bone scan were 93.4% and 92.5%, as well as 93.5% and 72.5%, respectively. In conclusion, our data suggest that FDG-PET with the same sensitivity and a better accuracy than those of Tc-99m MDP bone scan to detect metastatic bone lesions in patients with biopsy-proven NSCLC and suspected to have stage IV disease.

Adult↗
PubMed2002

Usefulness of whole body positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to detect recurrent ovarian cancer based on asymptomatically elevated serum levels of tumor marker.

The aim of this study was to evaluate practice usefulness of whole body positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to detect recurrent ovarian cancer based on asymptomatically elevated tumor marker (CA-125) serum levels. Whole-body FDG-PET was performed in 28 patients with suspected recurrent ovarian cancers and asymptomatically increased serum levels of tumor marker (CA-125 antigen) but negative or equivocal other imaging modality results. All of these 28 asymptomatic patients had serum levels of CA-125 antigen >35 U/ml. The final diagnosis of recurrent ovarian cancer was established by operation/biopsy histopathological findings or clinical follow-up longer than 1 year by additional morphologic imaging techniques. Among the 28 patients, the final diagnoses of recurrent ovarian cancers and benign lesions were established in 20 and 8 patients, respectively. FDG-PET accurately diagnosed recurrent ovarian cancers in 19 patients and benign lesions in 7 patients. When asymptomatically elevated serum levels of CA-125 antigen, the diagnostic sensitivity, specificity, and accuracy of FDG-PET to detect recurrent ovarian cancers were 95.0%, 87.5%, and 92.9%, respectively. FDG-PET is a useful technique to detect recurrent ovarian cancers for patients suspected of recurrent ovarian cancers due to asymptomatically elevated serum levels of CA-125 antigen.

Aged↗
PubMed2002

Early predicting recurrent cervical cancer with combination of tissue polypeptide specific antigen (TPS) and squamous cell carcinoma antigen (SCC).

The establishment of new tumor marker combinations including strong lead-time effects in detecting recurrent cervical cancer appears to be warranted. This retrospective study includes 50 patients with recurrent squamous cell cervical cancer after operation or radiotherapy. The serial serum levels of the tumor markers tissue polypeptide specific antigen (TPS) and squamous cell carcinoma antigen (SCC) were determined. Cutoff values of 78.5 U/L for TPS and 1.5 microg/L for SCC were selected according to the 95th percentile of serum concentrations measured in healthy control patients. Comparing with other monitoring modalities, SCC and TPS showed lead-time effective in 27 and 30 cases, respectively. This difference was not statistically significant. The combination of SCC and TPS provided lead-time effects in 42 cases. Our data indicate that combination of TPS and SCC is a valuable tool in the early predicting recurrent cervical cancer.

Adult↗