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Ruoh-Fang Yen

Publications and source records attributed to Ruoh-Fang Yen.

35 records · Page 2Linked to original sources
PubMed2003

Usefulness of Tc-99m HMPAO-labeled WBC heart scan to predict impaired ventricular function and coronary artery dilation in children with Kawasaki disease.

Forty-nine children with Kawasaki disease were included in this study. Based on the severity of carditis as determined by Tc-99m HMPAO-labeled WBC heart scan, the children were separated into two groups. Group A (n=24) had significant carditis and group B (n=25) did not have significant carditis. The left and right ventricular ejection fractions (LVEF and RVEF) were evaluated by equilibrium multigated blood pooling ventriculography. Diameters of the left and right coronary arteries (LCA and RCA) were measured by two-dimensional echocardiography. The results showed that group A had lower LVEF and RVEF, but larger diameters of the LCA and RCA than those of group B patients. The sensitivity of significant carditis to predict left ventricular dysfunction, right ventricular dysfunction, LCA dilation and RCA dilation was 88.9, 70.6, 75, and 71.4%, respectively; the specificities were 100, 100, 100, and 67.9%, respectively. Our findings suggest that significant carditis determined by Tc-99m HMPAO-labeled WBC heart scan can accurately predict impaired ventricular function and coronary artery dilation.

Child, Preschool↗
PubMed2003

Compare FDG-PET and Tc-99m tetrofosmin SPECT to detect metastatic thyroid carcinoma.

RATIONALE AND OBJECTIVES: The effectiveness of 18-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) and technetium-99m tetrofosmin (Tc-99m TF) single photon emission computed tomography (SPECT) of neck and chest was evaluated to detect metastatic lesions in well-differentiated thyroid carcinoma after nearly total thyroidectomy and radioiodine (I-131) treatment who present with elevated serum human thyroglobulin levels but negative I-131 whole body scan. MATERIALS AND METHODS: Twenty-three patients with differentiated thyroid carcinoma who underwent nearly total thyroidectomy and I-131 treatments were included in this study. RESULTS: All of the 23 patients had negative I-131 whole body scan and elevated human thyroglobulin levels under thyroid-stimulating hormone stimulation. Metastatic lesions were detected by FDG-PET in 20 patients, while Tc-99m TF SPECT revealed metastatic lesions in only 11 of the 20 patients. Both FDG-PET and Tc-99m TF SPECT failed to demonstrate miliary pulmonary metastases in two of the remaining three patients. The other patient did not show any lesion on FDG-PET, Tc-99m TF SPECT, chest computed tomography, or other imaging techniques. CONCLUSION: This study demonstrated that FDG-PET is more sensitive than Tc-99m TF SPECT to detect metastatic lesions in differentiated thyroid carcinoma with elevated human thyroglobulin but negative I-131 whole body scan. However, miliary pulmonary metastases could be missed by the both techniques.

Adult↗
PubMed2003

Differentiating solitary pulmonary metastases in patients with extrapulmonary neoplasmas using FDG-PET.

The purpose of this preliminary study is to evaluate the characteristics of solitary pulmonary lesions in patients using extrapulmonary neoplasmas with 18F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET). Thirty-two patients with extrapulmonary neoplasmas who had solitary pulmonary lesions and were suspected for pulmonary metastasis underwent an oncological survey with FDG-PET. Standard uptake value (SUV) and the ratio of lesion-to-background (L/B ratio) were used as parameters to differentiate and characterize the solitary pulmonary lesions. Using SUV > 2.5 or L/B ratio > 3 as the cutoff to diagnose malignancy, FDG-PET correctly identified 29 true-positive cases. However, FDG-PET failed to interpret two false-positive and one false-negative cases. The accuracy of FDG-PET was 91%. We concluded that FDG-PET is an accurate modality to differentiate solitary pulmonary lesions in patients with extrapulmonary neoplasmas.

Adult↗
PubMed2003

Tc-99m MIBI SPECT in detecting metastatic papillary thyroid carcinoma in patients with elevated human serum thyroglobulin levels but negative I-131 whole body scan.

UNLABELLED: Papillary carcinomas are the most common thyroid malignancies. They invade the regional lymphatics and metastasize frequently to local lymph nodes in the neck. Distant metastasis, generally to the lungs, is also common. The aim of this study is to evaluate the effectiveness of single photon emission computed tomography (SPECT) with technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) in detecting metastatic lesions in patients with papillary thyroid carcinoma (PTC) after nearly total thyroidectomy and radioiodine (I-131) treatment who present with elevated serum human thyroglobulin (hTg) levels but negative I-131 whole body scan (WBS). METHODS: Twenty patients of PTC who underwent nearly total thyroidectomy and I-131 treatments were included in this study. All of the 20 patients had negative I-131 WBS results and elevated hTg levels (hTg > or = 20 microIU/mL) under thyroid-stimulating hormone (TSH) stimulation (TSH > or = 30 microIU/mL). Technetium-99m MIBI SPECT was performed to detect metastatic lesions. RESULTS: Technetium-99m MIBI SPECT demonstrated lesions in 10 patients. Technetium-99m MIBI SPECT failed to demonstrate lesions in nine patients including small lymph node and lung metastases. CONCLUSIONS: This study showed that Tc-99m MIBI SPECT is a useful tool to detect metastatic lesions in PTC with elevated hTg but negative I-131 WBS. However, small lymph node and lung metastases may be missed in Tc-99m MIBI SPECT. In the latter circumstance, other imaging studies should be included in the follow-up protocol.

Adult↗
PubMed2003

Evolving metabolic changes during the first postoperative year after subthalamotomy.

OBJECT: Short-term benefit from unilateral subthalamotomy for advanced Parkinson disease (PD) is associated with metabolic alterations in key targets of subthalamic nucleus (STN) and globus pallidus (GP) output. In this study positron emission tomography (PET) scanning was used to assess these changes and their relation to long-term benefits of subthalamotomy. METHODS: To determine whether the early postoperative changes persisted at longer-term follow up, the authors assessed six patients with advanced PD by using [18F]fluorodeoxyglucose-PET at 3 and 12 months postsurgery. The authors compared each of the postoperative images with baseline studies, and assessed interval changes between the short- and long-term follow-up scans. Clinical improvement at 3 and 12 months was associated with sustained metabolic decreases in the midbrain GP internus (GPi), thalamus, and pons of the lesioned side (p < 0.01). The activity of a PD-related multiregional brain network, which correlated with bradykinesia and rigidity, was reduced at both postoperative time points (p < 0.05). Comparisons of 3- and 12-month images revealed a relative metabolic increase in the GP externus (GPe) (p < 0.001), which was associated with worsening gait, postural stability, and tremor at long-term follow up. CONCLUSIONS: These findings indicate that subthalamotomy may have differential effects on each of the functional pathways that mediate parkinsonian symptomatology. Sustained relief of akinesia and rigidity is associated with suppression of a pathological network involving the GPi and its output. In contrast, the recurrence of tremor may relate to changes in the function of an STN-GPe oscillatory network.

Adult↗
PubMed2002

Detection of recurrent or persistent nasopharyngeal carcinomas after radiotherapy with technetium-99m methoxyisobutylisonitrile single photon emission computed tomography and computed tomography: comparison with 18-fluoro-2-deoxyglucose positron emission tomography.

BACKGROUND: The diagnostic accuracy of technetium-99m methoxyisobutylisonitrile (Tc-MIBI) single photon emission computed tomography (SPECT) and computed tomography (CT) of the head and neck for differentiating recurrent or residual nasopharyngeal carcinomas (NPC) from benign lesions after radiotherapy was compared with positron emission tomography (PET) with 18-fluoro-2-deoxyglucose (FDG). METHODS: Thirty six NPC patients underwent head and neck CT, Tc-MIBI SPECT, and FDG-PET four months after radiotherapy to differentiate recurrent or residual NPC from benign lesions. Histopathologic examinations of nasopharyngeal biopsies were performed for all 36 patients. No patients had multiple foci of NPC. RESULTS: Based on biopsy results, the sensitivity, specificity, and accuracy of CT for differentiating recurrent or residual NPC from benign lesions were 73%, 88%, and 83%, respectively. The sensitivity, specificity, and accuracy of Tc-MIBI SPECT were 73%, 96%, and 89%, respectively. The sensitivity, specificity, and accuracy of FDG-PET were 100%, 96%, and 97%, respectively. Combination CT and Tc-MIBI SPECT for 28 NPC patients with congruent results showed the same sensitivity, specificity, and accuracy of 100%, 96%, and 96%, respectively, as FDG-PET for differentiating recurrent or residual NPC from benign lesions. In eight patients with incongruent results between CT and Tc-MIBI SPECT, FDG-PET correctly differentiated two benign lesions and six recurrent or residual NPCs. CONCLUSIONS: In detecting recurrent or residual NPC, FDG-PET is the best tool. However, combined use of CT and Tc-MIBI SPECT can result in the same accuracy as FDG-PET.

Adolescent↗
PubMed2002

Fluorine-18 FDG-PET in detecting local recurrence and distant metastases in breast cancer--Taiwanese experiences.

Fluorine-18 fluorodeonyglucose positron emission tomography (FDG-PET) was used to detect local recurrence, axillary lymph node (LN) involvement and distant metastases in patients with breast cancer. Thirty-six female patients with breast cancer s/p operation underwent FDG-PET studies. Findings were confirmed by histology following surgery and/or biopsy or negative follow-up results over a period of at least one year. In the evaluation of local recurrence, the diagnostic sensitivity, specificity, and accuracy of FDG-PET was 100, 96.8, and 97.2%, respectively. In the evaluation of axillary LN involvement, sensitivity, specificity, and accuracy was 80, 100, and 97.2%, respectively. In the evaluation of distant metastases, the diagnostic sensitivity, specificity, and accuracy was 83.3, 85.2, and 84.4%, respectively. The FDG-PET is a useful diagnostic tool in detecting local recurrence, axillary LN involvement, and distant metastasis.

Adult↗
PubMed2002

Clinical impact of [(18)F]FDG-PET in patients with suspected recurrent breast cancer based on asymptomatically elevated tumor marker serum levels: a preliminary report.

OBJECTIVE: To evaluate retrospectively the impact of [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) on the detection of recurrent breast cancer based on asymptomatically elevated tumor markers levels. METHODS: Whole-body FDG-PET was performed in 30 patients with suspected recurrent breast cancer and asymptomatic tumor marker increase but negative or equivocal other imaging modality results. A blood sample was drawn in each case for marker assay (CA 15-3 and CEA) on the same day as the FDG-PET. All of these 30 asymptomatic patients had either CA l5-3 >32 U/ml or CEA >5 ng/ml. The final diagnosis of recurrent breast cancer was established by operation/biopsy histopathological findings or clinical follow-up for >1 year by additional morphological imaging techniques. RESULTS: Among the 30 patients, the final diagnosis of recurrent breast cancer was established in 38 sites in 28 patients. FDG-PET accurately detected 35/38 sites in 25/28 patients with recurrence. The diagnostic sensitivity and accuracy of FDG-PET in patients with suspected recurrent breast cancer and asymptomatically elevated tumor markers were 96 and 90%, respectively. CONCLUSIONS: FDG-PET is a useful technique for detecting recurrent breast cancer suspected from asymptomatically elevated tumor markers levels and has an important clinical impact on the management of these patients.

Adult↗
PubMed2002

Predicting chemotherapy response to paclitaxel-based therapy in advanced non-small-cell lung cancer (stage IIIb or IV) with a higher T stage (> T2). Technetium-99m methoxyisobutylisonitrile chest single photon emission computed tomography and P-glycoprotein express ion.

OBJECTIVE: The aim of this study was to compare technetium-99m methoxyisobutylisonitrile (Tc-MIBI) chest single photon emission computed tomography (SPECT) results, immunohistochemical analyses of P-glycoprotein (Pgp) expression and response to paclitaxel in non-small-cell lung cancer (NSCLC). METHODS: Before chemotherapy with paclitaxel, 30 patients with stage IIIb or IV NSCLC were enrolled in this study. Early chest SPECT was performed 10 min after intravenous injection of Tc-MIBI. Tc-MIBI chest SPECT images were qualitatively interpreted. Early tumor-to-normal lung ratios (T/NL) were calculated quantitatively. Immunohistochemical analyses were performed on multiple nonconsecutive sections of the biopsy specimens to determine Pgp expression. Chemotherapy response was evaluated in the third month after completion of treatment by clinical and radiological methods. RESULTS: All 15 (100%) cases with good response and negative Pgp expression had positive results of early Tc-MIBI chest SPECT. Ten of 15 (67%) cases with poor response and positive Pgp expression had negative results of early Tc-MIBI chest SPECT. These early T/NL ratios (3.3 +/- 0.8 for the 15 patients with good response and 2.0 +/- 0.2 for the 5 patients with poor response) in lung cancer could be detected on early Tc-MIBI chest SPECT. The difference was significant (p < 0.05) by an independent Student t test. However, no significant differences were found for other prognostic factors (age, sex, body weight loss, performance status, tumor cell type, and tumor stage) between the good and poor response groups. CONCLUSION: Early Tc-MIBI chest SPECT can be used to understand the Pgp expression in NSCLC and to quickly predict chemotherapy response to paclitaxel.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2002

Subthalamotomy for advanced Parkinson disease.

OBJECT: The aim of this study was to determine if subthalamotomy is effective in treating advanced Parkinson disease (PD). METHODS: The authors performed microelectrode mapping-guided stereotactic surgery on the subthalamic nucleus in eight patients with PD. Lesioning was performed using radiofrequency heat coagulation and confirmed with magnetic resonance imaging. Three patients who underwent unilateral and four with bilateral subthalamotomy were evaluated for up to 18 months according to the Unified PD Rating Scale (UPDRS). One patient who underwent unilateral subthalamotomy died 6 months postsurgery. At 3 months into the "off" period after surgery, there were significant improvements in contralateral bradykinesia (p < 0.0002), rigidity (p < 0.0001), tremor (p < 0.01), axial motor features (p < 0.02), gait (p < 0.03), postural stability (p < 0.03), total UPDRS scores (p < 0.03), and Schwab and England scores (p < 0.04). The benefits were sustained at 6, 12, and 18 months, except for the improvement in tremor. At 12 months into the "on" period, significant benefits were present for motor fluctuation (p < 0.04), on dyskinesia (p < 0.006), off duration (p < 0.05), total UPDRS score (p < 0.02), and contralateral tremor (p < 0.05). Benefits for motor fluctuation, off duration, and off-period tremor were lost after the 18-month follow-up period. The levodopa requirement was reduced by 66% for the unilateral and 38% for the bilaterally treated group. Bilateral subthalamotomy offered more benefits than did unilateral surgery for various parkinsonian features in both the on and off periods. Three patients suffered hemiballismus, two recovered spontaneously, and one died of aspiration pneumonia after discontinuation of levodopa. CONCLUSIONS: These findings indicate that subthalamotomy can ameliorate the cardinal symptoms of PD, reduce the dosage of levodopa, diminish complications of the drug therapy, and improve the quality of life.

Aged↗
PubMedDate not supplied

Assessment of myocardial viability using F-18 fluorodeoxyglucose/Tc-99m sestamibi dual-isotope simultaneous acquisition SPECT: comparison with Tl-201 stress-reinjection SPECT.

BACKGROUND: This study compared technetium 99m sestamibi/fluorine 18 fluorodeoxyglucose dual-isotope simultaneous acquisition (DISA) with stress-reinjection thallium 201 single photon emission computed tomography (SPECT) with regard to their ability to detect myocardial viability. METHODS AND RESULTS: The study cohort consisted of 42 angiographically significant coronary artery disease patients with symptomatic congestive heart failure or regional wall motion abnormalities. In total, 398 dysfunctional segments in 40 patients were analyzed (2 patients were excluded because of poor-quality F-18 fluorodeoxyglucose images). Of the segments, 217 were diagnosed as viable and 144 as nonviable by both DISA and Tl-201, 33 were viable by DISA but nonviable by Tl-201, and 4 were viable by Tl-201 but nonviable by DISA. Most discrepancies were in the inferior wall. Of the 40 patients, 16 underwent revascularization. From the follow-up results for the 105 dysfunctional segments in these 16 patients, DISA viability appears to be a significant predicting factor (P = .014) for functional recovery after revascularization statistically whereas Tl-201 viability does not (P = .09). CONCLUSION: Our study suggests that DISA viability provides more accurate prediction of postrevascularization functional recovery than Tl-201 viability. Given the small number of patients who underwent revascularization, the superiority of DISA over Tl-201 in detecting myocardial viability may be firmly established by further study on a large scale for patients with profound left ventricular dysfunction.

Adult↗
PubMedDate not supplied

Tl-201 myocardial SPECT in differentiation of ischemic from nonischemic dilated cardiomyopathy in patients with left ventricular dysfunction.

BACKGROUND: The differentiation between ischemic and nonischemic cardiomyopathy by noninvasive modalities is of clinical importance. Whether thallium 201 single photon emission computed tomography (SPECT) could accurately distinguish the two groups remains unclear. METHODS AND RESULTS: Twenty-nine patients with chronic heart failure (left ventricular ejection fraction < or =40%), including fourteen patients with ischemic cardiomyopathy and fifteen patients with nonischemic dilated cardiomyopathy, underwent Tl-201 SPECT. The stress protocols included treadmill exercise in 8 patients, dipyridamole in 6 patients, and dobutamine infusion in 15 patients. Myocardial SPECT was interpreted with the use of a 17-segment model and 0- to 4-point scale system. Patients with ischemic cardiomyopathy had higher summed stress defect scores (27.9 +/- 9.4 vs 20.6 +/- 8.9, P =.04), more fixed defect segments (5.9 +/- 2.9 vs 3.8 +/- 2.9, P =.05), and more moderate or severe perfusion defect segments on stress scan (7.2 +/- 2.0 vs 4.5 +/- 2.6, P =.004) than did those with nonischemic dilated cardiomyopathy. However, considerable overlap of the scan patterns between the two groups existed. Moderate or severe perfusion defects on stress scan in at least 7 segments were noted in 71% of patients (10/14) with ischemic cardiomyopathy, as compared with 20% of patients (3/15) with nonischemic cardiomyopathy (P =.016). CONCLUSIONS: Assessment of Tl-201 myocardial SPECT yields only modest value to distinguish nonischemic dilated cardiomyopathy from ischemic cardiomyopathy in patients with chronic heart failure. This technique cannot clearly differentiate individual patients.

Cardiomyopathy, Dilated↗
PubMedDate not supplied

Comparison of 18F-fluoro-2-deoxyglucose positron emission tomography and gallium-67 citrate scintigraphy for detecting malignant lymphoma.

This study evaluates and compares the accuracy of positron emission tomography with 18F-fluoro-2-deoxyglucose (FDG-PET) and gallium-67 citrate (Ga-67) scintigraphy in identifying disease sites in patients with malignant lymphoma at initial diagnosis or relapse. Histology subgroups included low (n=5), intermediate (n=6), high-grade (n=5) non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD) (n=14). Ann-Arbor staging included 7 patients in stage I, 8 in stage II, 9 in stage II, 6 in stage IV and 11 extra-nodal. In this study, before any therapy, 25 contemporaneous FDG-PET and Ga-67 scintigraphies were performed on patients with either NHL (16) or HD (14). One hundred and eleven sites of disease were correlated on a site-by-site basis in corresponding areas of FDG-PET and Ga-67 scintigraphy. Discordant FDG-PET and Ga-67 scintigraphic findings were correlated with CT/MRI and clinical evaluation. FDG-PET detected malignant lymphoma in 24/25 patients (sensitivity: 96.0%). There was a false-negative FDG-PET result in only 1 patient with low-grade gastric malignant lymphoma. Ga-67 scintigraphy detected malignant lymphoma in 18/25 patients (sensitivity: 72.0%). There were false-negative Ga-67 scintigraphic results in 4 cases with low-grade non-Hodgkin's lymphoma, 2 cases with bone or bone marrow involvement, and 3 smaller disease sites. FDG-PET upstaged 6 patients in whom Ga-67 scintigraphy detected disease sites partially. In imaging lymphoma prior to therapy, FDG-PET had a higher sensitivity and detected significantly more disease sites when compared with Ga-67 scintigraphy in the initial evaluation of this group of patients. Upstaging of patients with FDG-PET may result in a change in treatment strategy. However, evaluation of the final sensitivity, specificity and accuracy of these imaging modalities will need a further study with a larger patient number.

Adult↗
PubMedDate not supplied

Tissue polypeptide specific antigen (TPS) as a tumor marker in renal cell carcinoma.

Tissue polypeptide specific antigen (TPS) is a new tumor marker that indicates tumor proliferative rate rather than tumor burden. The purpose of this study was to assess the clinical value of TPS in patients with renal cell carcinoma (RCC). Serum levels of TPS were measured in 30 patients with locoregional and in 20 patients with advanced disease before and after therapy. The results showed that: (1) the detection sensitivity of TPS for RCC is 60.0%; (2) the detection sensitivity of TPS in advanced RCC (100.0%) was significantly higher than in locoregional RCC (33.3%); (3) the 10 locoregional RCC patients without recurrence had normal serum TPS levels during a follow-up period of 1 year; and (4) the 8 advanced RCC patients with good response during therapy had normal serum TPS levels, while 12 patients with poor disease had significantly elevated serum TPS levels during a follow-up period of 1 year. Our results suggest that TPS may have a potential clinical role as a valuable tumor marker for RCC, especially in advanced diseases and follow-up therapy response.

Adult↗
PubMedDate not supplied

Detecting metastatic neck lymph nodes in papillary thyroid carcinoma by 18F-2-deoxyglucose positron emission tomography and Tc-99m tetrofosmin single photon emission computed tomography.

The aim of this study was to evaluate the usefulness of 18-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) and technetium-99m tetrofosmin (Tc-99m TF) single photon emission computed tomography (SPECT) to detect metastatic neck lymph nodes (LN) in papillary thyroid carcinoma (PTC) after total thyroidectomy and radioiodine-131 (I-131) treatments in patients with elevated serum human thyroglobulin (hTg) levels but negative I-131 whole body scan (WBS). Thirteen PTC patients underwent nearly total thyroidectomy and I-131 treatments with proven neck LN metastases were included in this study. All subjects had negative I-131 WBS and elevated hTg levels (hTg > or = 10 mu IU/ml) under thyroid-stimulating hormone (TSH) stimulation (TSH > or = 30 mu IU/ml). FDG-PET and Tc-99m TF SPECT were used to detect metastatic neck LN in PTC. FDG-PET could detect all of the 13 (100%) patients with metastatic neck LN, but Tc-99m TF SPECT revealed lesions in only 8 out of 13 (61.5%) patients (p < 0.05). This study demonstrated that FDG-PET is more sensitive than Tc-99m TF SPECT to detecting metastatic neck LN in PTC with elevated serum hTg levels but negative I-131 WBS.

Adult↗
PubMedDate not supplied

Comparison of FDG-PET and technetium-99m MIBI SPECT to detect metastatic cervical lymph nodes in well-differentiated thyroid carcinoma with elevated serum HTG but negative I-131 whole body scan.

The aim of this study was to evaluate the usefulness of 18-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) and technetium-99m methoxyisobutylisonitrile (Tc-99m MIBI) single photon emission computed tomography (SPECT) in detecting metastatic cervical lymph nodes (LN) in well-differentiated thyroid carcinoma (DTC) after total thyroidectomy and radioiodine-131 (I-131) treatments in patients with elevated serum human thyroglobulin (hTg) levels but negative I-131 whole body scan (WBS). Fifteen DTC patients underwent nearly total thyroidectomy and I-131 treatments with cervical LN metastases were included in this study. All subjects had negative I-131 WBS and elevated hTg levels (hTg > or = 10 microIU/ml) under thyroid-stimulating hormone (TSH) stimulation (TSH > or = 30 microIU/ml). FDG-PET could detect all of the 15 (100%) patients with metastatic cervical LN, but Tc-99m MIBI SPECT revealed lesions in only 9 out of 15 (60%) patients (p value < 0.05). This study demonstrated that FDG-PET is more sensitive than Tc-99m MIBI SPECT in detecting metastatic cervical LN in DTC with elevated serum hTg levels but negative I-131 WBS.

Adult↗