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Chung-Huei Hsu

Publications and source records attributed to Chung-Huei Hsu.

15 recordsLinked to original sources
PubMed2007

The significance of FDG uptake in bilateral thyroid glands.

AIM: To evaluate the significance of bilateral fluorodeoxyglucose (FDG) uptake in the thyroid glands. METHODS: Bilateral thyroid FDG uptake, defined as visualization of thyroid glands, was found in 66 (3.4%) of 1925 subjects who underwent our FDG PET cancer-screening program. Additionally, 16 of the 41 patients with Graves' disease and hyperthyroidism (GD(H)) and six of the 20 subjects with Graves' disease and euthyroidism (GD(E)), who had FDG uptake in thyroid glands, were enrolled in this study. RESULTS: Among the 66 subjects, 22 were normal variant, 39 subjects had chronic thyroiditis (35 subjects presented with diffuse goitre and four with multinodular goitre), and five subjects had multinodular goitre (MNG) without chronic thyroiditis. Fourteen of 22 (63.6%) of the subjects with the normal variant had a visual uptake intensity less than that of the liver, while 30 of 39 (76.9%) of the subjects with chronic thyroiditis and 14 of 22 (63.6%) of the subjects with Graves' disease had visual uptake intensity greater than or equal to liver uptake. Two of the five subjects with MNG with focally intense uptake were proven to have thyroid carcinoma. Bilateral loser uptake in thyroids associated with thymus and symmetrical skeletal muscle uptake were found in GD(H). The standard uptake value (SUV) (mean+/-SD) in subjects with chronic thyroiditis (2.76+/-1.24) were higher, while those with GD(H) (1.59+/-0.36) were lower than that of the normal variant (1.99+/-0.63). Subjects with hypothyroidism (3.04+/-1.39) had higher SUV levels than those subjects with euthyroidism (2.44+/-1.11). In addition, patients with GD(H) had lower levels than those with GD(E) (2.0+/-0.38). CONCLUSION: (1) Bilateral thyroidal uptake of FDG can be found in normal variants and subjects with various thyroid disorders, showing varieties of uptake patterns. (2) Diffuse intense uptake and higher SUV levels are a clue to a diagnosis of chronic thyroiditis, especially for those with hypothyroidism. (3) Focally intense uptake suggests the possibility of a thyroid carcinoma. (4) Sparse uptake associated with the thymus and symmetrical skeletal muscle uptake and lower SUV level raise the possibility of Graves' disease with hyperthyroidism.

Adult↗
PubMed2007

Utility of 18F-FDG PET/CT uptake patterns in Waldeyer's ring for differentiating benign from malignant lesions in lateral pharyngeal recess of nasopharynx.

UNLABELLED: Focally increased (18)F-FDG uptake in the lateral pharyngeal recess (LPR) of the nasopharynx due to a benign or malignant lesion is not an uncommon finding on PET images. The aim of this study was to evaluate whether, on PET/CT images, (18)F-FDG uptake occurs with characteristic patterns and intensities in various regions of Waldeyer's ring that can improve our ability to differentiate benign from malignant lesions. METHODS: Data generated from the (18)F-FDG PET/CT images of 1,628 subjects in our cancer-screening program were analyzed. Increased uptake in the LPR was observed in 80 subjects (4.9%) presenting with benign lesions, including 53 subjects without and 27 subjects with symptoms of upper airway discomfort. In addition, 30 healthy controls and 21 patients with newly diagnosed nasopharyngeal carcinoma were recruited for this study. Visual uptake, measurements of the lesions' standardized uptake value (SUV), and any abnormalities on PET/CT were evaluated. The receiver-operating-characteristic curve and area under the curve were applied to evaluate the discriminating power. RESULTS: Increased (18)F-FDG uptake (SUV, mean +/- SD) was found in the LPR, with a statistically significant (P < 0.001) difference between benign lesions (3.0 +/- 1.16) and malignant lesions (7.03 +/- 3.83). However, associated increased uptake exclusively in the palatine tonsil, lingual tonsil, and submandibular gland was found in both asymptomatic and symptomatic subjects. The ratio of LPR uptake to palatine tonsil uptake (N/P ratio) in benign lesions (0.81 +/- 0.37) was significantly (P < 0.001) lower than that in malignant lesions (2.30 +/- 1.62). Higher incidences of asymmetric (18)F-FDG LPR uptake, cervical lymph node uptake, and asymmetric wall thickening of the LPR on CT were observed in patients with nasopharyngeal carcinoma. When an SUV of less than 3.9 and an N/P ratio of less than 1.5 were used as cutoff points in subjects showing the combination of symmetric uptake in the LPR and normal or symmetric wall thickening, and detectable lymph node uptake, the area under the curve for benign lesions on PET/CT was 0.932 +/- 0.042 (95% confidence interval, 0.86-0.98), with a sensitivity of 90.4% and a specificity of 93.8%. CONCLUSION: The intensity and patterns of (18)F-FDG uptake in various regions of Waldeyer's ring along with CT scan findings provide a feasible modality to differentiate benign from malignant nasopharyngeal lesions.

Adult↗
PubMed2003

Intense uptake of [F-18]-fluoro-2 deoxy-D-glucose in active pulmonary tuberculosis.

FDG PET is well recognized for its utility in cancer workup. Nonetheless, the differentiation between malignant and benign pulmonary lesions by FDG PET is challenging. The authors report three proved cases of pulmonary tuberculosis in acute active and open stages. The activities and extents of infection were demonstrable in FDG PET, which could not be observed in either chest radiograph or computed tomography.

Adult↗
PubMed2003

Neurofibroma with increased uptake of [F-18]-fluoro-2 deoxy-D-glucose interpreted as a metastatic lesion.

We report a patient with a solitary spinal neurofibroma in the posterior mediastinum interpreted as a metastatic tumor. A 46-year-old female with rectal cancer who had undergone operation and subsequent adjuvant chemotherapy two years previously was referred to our department for a follow-up whole body FDG-PET study. PET scan revealed a mass with increased uptake of FDG (SUV = 4.6) in the posterior mediastinum. MRI examination showed a dumbbell neurogenic tumor originating from the intercostal nerve at T6 level. A subsequent CT-guided biopsy demonstrated a neurofibroma.

Diagnosis, Differential↗
PubMed2003

Using Tc-99m DMSA renal scan to detect renal damage in Taiwanese women with Type 2 diabetes--a preliminary report.

UNLABELLED: In this preliminary study, we compared control women and Type 2 diabetes mellitus (DM) women for the prevalence and type of renal damage as revealed by technetium-99m dimercapto-succinic acid (Tc-99m DMSA) renal scan. METHODS: A total of 20 control women and 60 women with Type 2 DM received Tc-99m DMSA renal scan were included in this study. The 60 women with Type 2 DM were separated into three groups: 20 women without UTI history, 20 patients with cystitis histories only, and 20 with pyelonephritis histories. RESULTS: All of the control women had normal Tc-99m DMSA renal scan findings. However, 38.3% of Type 2 DM wonmen had abnormal Tc-99m DMSA renal scan findings. Type 2 DM women without UTI history had no abnormal scan findings. The prevalence of abnormal renal scan findings was significantly higher in Type 2 DM women with pyelonephritis (90.0%) than with cystitis alone (25.0%). Renal scar findings were found only in Type 2 DM women with pyelonephritis (40.0%). CONCLUSIONS: Compared with control women, women with Type 2 DM, especially if they had UTI and pyelonephritis histories, have a significantly higher prevalence of abnormal Tc-99m DMSA renal scan findings.

Case-Control Studies↗
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

F-18 fluorodeoxyglucose positron emission tomography in pulmonary cryptococcoma.

Cryptococcosis is not uncommon. Potential interpretation pitfalls should be kept in mind when fluorodeoxyglucose (FDG) positron emission tomography (PET) is used for differentiating pulmonary nodules and for discriminating infection from malignancy, especially in areas where the prevalence of granulomatous infection is high and in immunocompromised patients. In this case, a nodular mass was shown on chest radiography and computed tomographic (CT) scanning. A consolidated infection or a bronchioloalveolar carcinoma was suspected because the CT scan showed air bronchograms within the mass and another perihilar infiltration. The FDG PET scan clearly delineated the lesion and had intermediately high glucose uptake (standard uptake value, 3.8-4.0), which led to the exclusion of the possibility of bronchioloalveolar carcinoma because most of these tumors had normal or mildly increased FDG accumulation. Cryptococcoma was finally diagnosed. Hence, the CT scan and FDG PET played complementary roles in the differential diagnosis of this nodular mass.

Cryptococcosis↗
PubMed2002

Complementary role of 18F-fluorodeoxyglucose positron emission tomography and 131I scan in the follow-up of post-therapy differentiated thyroid cancer.

BACKGROUND AND PURPOSE: 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a relatively new modality in the follow-up of patients with differentiated thyroid cancer (DTC) who have undergone total thyroidectomy and postoperative radioiodine therapy. The aim of this study was to assess the diagnostic value of FDG-PET, comparing it with 131I whole-body scan (WBS) and 201Tl WBS. METHODS: Fifteen selected patients with local invasive and/or aggressive DTC were included in this study. The follow-up period ranged from 1 to 12 years, with a mean +/- standard error of 6 +/- 3 years. FDG-PET was performed when patients were still receiving thyroxin therapy. RESULTS: In the cervical region, residual cancer in two patients was demonstrated by FDG-PET, but could not be detected using 131I WBS or 201Tl WBS. Pathology of the surgical specimen showed dedifferentiation of thyroid cancer in one of these patients. Metastatic cervical lymph nodes were detected using FDG-PET in three patients, but in only one patient using 131I WBS and in another one patient using 201Tl WBS. Mediastinal metastases were detected using FDG-PET in three patients, 131I WBS in two patients, and 201Tl WBS in one patient. Diffuse lung metastasis was detected only by 131I WBS in two patients. The use of FDG-PET in conjunction with computerized tomography provided useful diagnostic information about small nodular lesions of the lung which could not be localized by 131I WBS or 201Tl WBS in three patients. In skeletal metastases, 131I WBS detected more metastatic lesions than FDG-PET or 201Tl WBS, especially when the lesions were located in the pelvis. CONCLUSIONS: In the follow-up evaluation of patients with post-therapy DTC, FDG-PET was useful for detecting dedifferentiated lesions and was superior to 131I WBS in detecting residual cervical or mediastinal lesions and suspected small metastatic foci in the lung. FDG-PET was inferior to 131I WBS in detecting diffuse lung metastases and distant bone metastases.

Adult↗