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ABSTRACT: The aim of this study was to detect brain functional deficits in patients with Behçet's disease (BD) and signs or symptoms of central nervous system (CNS) involvement at different times in their clinical history. A total of 24 patients aged 20 to 53years (median age 39years; 20 women, four men) with Behçet's syndrome fulfilling the diagnosis as defined by the syndrome classification were enrolled in this study. Single-photon emission computed tomography (SPECT) with (99m)Technetium (Tc)-hexamethylpropyleneamine oxime (HMPAO) as the perfusion tracer was performed to detect brain lesions. The results of (99m)Tc-HMPAO brain SPECT scans showed impaired perfusion in all cases with neurological complaints (24 out of 24, 100%). Temporal lobes and basal ganglia were the most common areas with such lesions. In contrast, brain MRI and CT images were normal or non-specific in all cases. In conclusion, (99m)Tc-HMPAO brain SPECT imaging is a powerful and sensitive tool for disclosing brain involvement in numerous clinical situations, even including patients with subtle neurological symptoms/signs such as headaches and dizziness. It is also a useful modality for evaluating the effects of treatment and disease monitoring to prevent CNS damage.
Journal of Neuroradiology 02/2013; · 1.21 Impact Factor
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Nuclear Medicine Communications 01/2013; · 1.40 Impact Factor
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ABSTRACT: Rapid determination of the inflammatory and sputum smear status in patients with pulmonary tuberculosis (PTB) is crucial for clinical decision making. The purpose of this study was to assess the relationship between gallium-67 (Ga-67) uptake by lung foci and sputum smear status in patients with PTB. We also attempted to predict the patients with acid-fast bacilli (AFB) smear-positive PTB by means of a semiquantitative measurement of Ga-67 uptake ratio using single-photon emission computed tomography images.
Ninety-five patients with PTB were enrolled in this retrospective study. A volume-of-interest method was used to quantify Ga-67 uptake in single-photon emission computed tomography images. The Ga-67 uptake ratio was defined as the maximum voxel value of the pulmonary lesion divided by the maximum voxel value of normal lung tissue.
The Ga-67 uptake ratio was higher in patients with active PTB than in those with inactive PTB (3.11 ± 1.52 vs. 1.42 ± 0.14, P<0.01). In active PTB, the Ga-67 uptake ratio was higher in smear-positive patients than in smear-negative patients (3.41 ± 1.60 vs. 2.16 ± 0.61, P<0.01). In patients with AFB smear grades 1+, 2+, and 3+, the Ga-67 uptake ratios were 2.51 ± 0.81, 3.30 ± 1.57, and 4.23 ± 1.73, respectively. The correlation between Ga-67 uptake ratio and AFB smear grading was statistically significant (Spearman's ρ=0.60, P<0.01). In receiver operating characteristic curve analyses, the area under the curve for the Ga-67 uptake ratio was 0.95 ± 0.02 (P<0.01) for predicting active PTB and 0.87 ± 0.04 (P<0.01) for predicting smear-positive active PTB.
In patients with active PTB, more-intense Ga-67 uptake was associated with more AFB load in the sputum - that is a greater potential to transmit PTB. This finding might facilitate clinical decision making for immediate isolation and treatment to reduce transmission of PTB.
Nuclear Medicine Communications 06/2012; 33(9):941-6. · 1.40 Impact Factor
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ABSTRACT: Brown adipose tissue (BAT) is important for regulating body weight. Environmental temperature influences BAT activation. Activated BAT is identifiable using (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT). (18)F-FDG PET/CT scans done between June 2005 and May 2009 in our institution in tropical southern Taiwan and BAT studies from PubMed (2002-2011) were reviewed, and the average outdoor temperatures during the study periods were obtained. A simple linear regression was used to analyze the association between the prevalence of activated BAT (P) and the average outdoor temperature (T). The review analysis for 9 BAT studies (n = 16, 765) showed a significant negative correlation (r = -0.741, P = 0.022) between the prevalence of activated BAT and the average outdoor temperature. The equation of the regression line is P(%) = 6.99 - 0.20 × T (°C). The prevalence of activated BAT decreased by 1% for each 5°C increase in average outdoor temperature. In a neutral ambient temperature, the prevalence of activated BAT is low and especially rare in the tropics. There is a significant linear negative correlation between the prevalence of activated BAT and the average outdoor temperature.
TheScientificWorldJOURNAL 01/2012; 2012:793039. · 1.66 Impact Factor
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ABSTRACT: Brown adipose tissue (BAT) has thermogenic potential. For its activation, cold exposure is considered a critical factor though other determinants have also been reported. The purpose of this study was to assess the relationship between neoplastic status and BAT activity by 2-deoxy-2-[(18)F]fluoro-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in people living in the tropics, where the influence of outdoor temperature was low.
(18)F-FDG PET/CT scans were reviewed and the total metabolic activity (TMA) of identified activated BAT quantified. The distribution and TMA of activated BAT were compared between patients with and without a cancer history. The neoplastic status of patients was scored according to their cancer history and (18)F-FDG PET/CT findings. We evaluated the relationships between the TMA of BAT and neoplastic status along with other factors: age, body mass index, fasting blood sugar, gender, and outdoor temperature.
Thirty of 1740 patients had activated BAT. Those with a cancer history had wider BAT distribution (p = 0.043) and a higher TMA (p = 0.028) than those without. A higher neoplastic status score was associated with a higher average TMA. Multivariate analyses showed that neoplastic status was the only factor significantly associated with the TMA of activated BAT (p = 0.016).
Neoplastic status is a critical determinant of BAT activity in patients living in the tropics. More active neoplastic status was associated with more vigorous TMA of BAT.
Lipids in Health and Disease 12/2011; 10:238. · 2.17 Impact Factor
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ABSTRACT: The purpose of this study was to compare the inflammatory activity of pulmonary lesions between active tuberculosis and nontuberculous mycobacterial (NTM) infection in acid-fast bacilli smear-positive non-HIV-infected patients using gallium-67 (Ga) scintigraphy.
Twenty-four patients with culture-proven active pulmonary tuberculosis (PTB) and an additional 17 patients meeting the criteria of pulmonary NTM infection were enrolled into the retrospective study. The Ga uptake of the pulmonary lesion was assessed by visual scoring of uptake grade and semiquantitative region of interest analysis of the uptake ratio using the thoracic spine as a reference.
Ga scans were positive in 23 of the 24 patients (95.8%) with PTB and in 12 of the 17 patients (70.6%) with pulmonary NTM infection. Twenty patients with active PTB had moderate or intense visual Ga uptake grade, whereas only three patients with pulmonary NTM infection had moderate visual Ga uptake grade. The semiquantitative pulmonary Ga uptake ratios in patients with active PTB and NTM infection were 1.17 ± 0.28 (range: 0.77-1.86) and 0.79 ± 0.12 (range: 0.60-1.03), respectively. The Ga uptake grade and ratio of active PTB were both significantly higher than NTM infection (both P < 0.001). In the receiver operating characteristic curve analysis for predicting active PTB, the area under the curves of Ga uptake grade and ratio were 0.90 ± 0.05 and 0.93 ± 0.04, respectively (both P < 0.001).
The inflammatory activity of active PTB is significantly higher than that of pulmonary NTM infection in non-HIV-infected patients. Ga uptake grade and ratio could be used to predict active PTB in acid-fast bacilli smear-positive patients.
Nuclear Medicine Communications 02/2011; 32(5):392-401. · 1.40 Impact Factor
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ABSTRACT: Brown adipose tissue (BAT) is a highly specialized thermogenic tissue and has profound effects on body weight, energy balance, and glucose metabolism. Body temperature regulation depends on the integrated activities of the autonomic nervous system, which is centered predominantly in the hypothalamus. The purpose of this study was to explore the interaction of brain and the activation of BAT by analyzing differences in brain metabolism between patients with and without activated BAT. Fluorodeoxyglucose (FDG) with positron emission tomography/computer tomography (PET/CT) was used to determine the activation of BAT and brain metabolism. After reviewing FDG PET/CT scans, we retrospectively collected 42 patients, 21 with activated BAT and 21 matched controls without activated BAT. We used the method of defining regions of interest (ROI) to examine differences in metabolism between their hypothalami and voxel (volumetric pixel)-based statistical parametric mapping to analyze the whole brain. Compared with controls, patients with activated BAT had a significant hypermetabolic area in the right inferior parietal lobule (Brodmann area 40) and significant hypometabolic areas in the left insula (Brodmann area 13) and right cerebellum; however, there were no metabolic differences in the hypothalamic regions. Our findings illustrate the close relationship of cold temperature exposure-triggered hypermetabolism in the right inferior parietal lobule and activated BAT. They also support the hypotheses that the insula and cerebellum regulate autonomic functions, which are important for controlling BAT thermogenesis within the central pathways.
NeuroImage 01/2011; 54(1):142-7. · 5.89 Impact Factor
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ABSTRACT: A 10-year-old boy complained of pain around his right hip for 3 weeks. He underwent Ga-67 scintigraphy to evaluate possible bone or joint infection. There was no pathologic Ga-67 uptake near the right hip; however, there was symmetrical Ga-67 uptake in his right and left upper chest. An immediate SPECT/CT scan showed radiotracer uptake in bilateral supraclavicular and subclavicular areas corresponding to the low-attenuation regions on CT as the common locations containing brown adipose tissue. Ga-67 uptake in brown adipose tissue is unusual. Integrated SPECT/CT is helpful for identifying this physiological Ga-67 uptake.
Clinical nuclear medicine 12/2009; 34(12):964-6. · 3.92 Impact Factor
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Clinical nuclear medicine 08/2009; 34(7):475-6. · 3.92 Impact Factor
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ABSTRACT: The aim of this study was to assess the reproducibility and diagnostic performance for coronary artery disease (CAD) of an automated software package, 4D-MSPECT, and compare the results with a visual approach. We enrolled 60 patients without previously known CAD, who underwent dual-isotope rest Tl-201/stress Tc-99m sestamibi myocardial perfusion imaging and subsequent coronary angiography within 3 months. The automated summed stress score (A-SSS), summed rest score (A-SRS) and summed difference score (A-SDS) were obtained using a 17-segment five-point scale model with 4D-MSPECT. For intraobserver and interobserver variability assessment, automated scoring was done by a nuclear medicine physician twice and by a nuclear medicine technologist. The visual summed stress score (V-SSS), summed rest score (V-SRS), and summed difference score (V-SDS) were obtained by consensus of two nuclear medicine physicians. The intraobserver and interobserver agreements of automated segmental scores were excellent. The intraobserver and interobserver summed scores also correlated well. Agreements between visual and automated segmental scores were moderate (weighted kappa of 0.55 and 0.50 for stress and rest images, respectively). Correlations between automated and visual summed scores were high, with correlation coefficients of 0.89, 0.85 and 0.82 for SSS, SRS and SDS, respectively (all p < 0.001). The receiver operating characteristic area under the curve for diagnosis of CAD by V-SSS, V-SDS, A-SSS and A-SDS were 0.78 +/- 0.06, 0.87 +/- 0.05, 0.84 +/- 0.05 and 0.90 +/- 0.04, respectively. A-SDS had better diagnostic performance than A-SSS and V-SSS (p = 0.043 and p = 0.032, respectively), whereas there was no statistically significant difference between A-SDS and V-SDS (p = 0.56). Using V-SDS > or = 2 as a diagnostic threshold, the sensitivity, specificity, and accuracy for CAD were 83.7%, 76.5% and 81.7%, respectively. Using A-SDS > or = 3 as a diagnostic threshold, the sensitivity, specificity, and accuracy for CAD were 79.1%, 82.4% and 80.0%, respectively. In conclusion, the reproducibility of automated semiquantitative analysis with 4D-MSPECT was excellent. The diagnostic performance of automated semiquantitative analysis with 4D-MSPECT was comparable with the visual approach.
The Kaohsiung journal of medical sciences 09/2008; 24(9):445-52. · 0.61 Impact Factor
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ABSTRACT: Infected aortic aneurysm is an uncommon life-threatening disease. A 68-year-old man had a history of type 2 diabetes mellitus and repeated urinary tract infections. He presented with fever, chills, low back pain, leukocytosis, and Salmonella group B bacteremia. For evaluation of suspected lumbar vertebral osteomyelitis, a 3-phase bone scan and a gallium-67 scan were performed. An abdominal aortic aneurysm was noted incidentally on the blood flow and blood pool phase images. Gallium-67 scan demonstrated increased radioactivity within the soft tissues surrounding the aneurysm, which was suggestive of an infected abdominal aortic aneurysm. The previously unsuspected infected abdominal aortic aneurysm was confirmed by computed tomography.
Clinical Nuclear Medicine 05/2008; 33(4):305-7. · 3.67 Impact Factor
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ABSTRACT: The use of 201Tl scintigraphy as a routine imaging modality in the follow-up of patients with differentiated thyroid carcinoma (DTC) is controversial. The purpose of this retrospective study was to evaluate the diagnostic accuracy and clinical impact of routine 201Tl scintigraphy in the follow-up of patients with DTC.
Three hundred and twenty-one patients (261 women, 60 men) with DTC (243 papillary thyroid carcinomas, 78 follicular thyroid carcinomas) were enrolled in this study. Two hundred and seventy-six patients underwent total or near total thyroidectomy (group 1) and 45 patients underwent subtotal thyroidectomy or unilateral lobectomy (group 2). A total of 1523 201Tl scintigraphy examinations were performed between 1987 and 2003. The duration of follow-up ranged from 13 to 204 months. 201Tl scintigraphy was performed 10 and 60 min after intravenous administration of 74 MBq 201Tl chloride.
In group 1, 55 recurrent lesions were confirmed in 39 patients. In a patient-based analysis, the sensitivity, specificity, positive and negative predictive values, and accuracy of 201Tl scintigraphy for detecting recurrent DTC were 71.8%, 98.3%, 87.5%, 95.5% and 94.6%, respectively. In a lesion-based analysis, the sensitivity, specificity, positive and negative predictive values, and accuracy of 201Tl scintigraphy were 63.6%, 99.7%, 89.7%, 98.5% and 98.3%, respectively. Of the 35 thallium-positive recurrent lesions, 21 (60%) were removed by surgery and seven (20%) were treated with external-beam radiation therapy. All the thallium-negative recurrent lesions were treated with 131I therapy. The difference between the management of thallium-positive and thallium-negative recurrences was statistically significant (P<0.001). In group 2, 10 recurrent lesions were confirmed in seven patients. In a patient-based analysis, the sensitivity, specificity, positive and negative predictive values, and accuracy of 201Tl scintigraphy for detecting recurrent DTC were 85.7%, 94.7%, 75%, 97.3% and 93.3%, respectively. In a lesion-based analysis, the sensitivity, specificity, positive and negative predictive values, and accuracy of 201Tl scintigraphy was 80%, 97.5%, 80%, 97.5% and 95.6%, respectively. All of the seven patients were treated with completion of total thyroidectomy and subsequent 131I ablation therapy.
201Tl scintigraphy was not a highly sensitive imaging modality in routine follow-up of patients with DTC after total thyroidectomy. However, it had a clinical impact on the choice of optimal therapeutic approaches. In the follow-up of patients who underwent partial thyroidectomy, 201Tl scintigraphy was useful in the detection of recurrent DTC.
Nuclear Medicine Communications 09/2007; 28(9):681-7. · 1.40 Impact Factor
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Clinical Nuclear Medicine 07/2006; 31(6):352-4. · 3.67 Impact Factor
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Clinical Nuclear Medicine 06/2006; 31(5):269-71. · 3.67 Impact Factor
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ABSTRACT: Sentinel lymph node (SLN) biopsy is an alternative to axillary node dissection for staging breast cancer treatment. In this article, we investigated nodal drainage patterns and tumor location using lymphoscintigraphy to predict the axillary sentinel lymph node status. We enrolled 88 patients with clinically suspicious or biopsy-proven breast cancer from March 2001 to October 2002. The average age of subjects was 48 +/- 4 years and the clinical stage was T(1-2)N0Mx. Tc-99m sulfur colloid was used in a hybrid combination of subdermal and perilesional injections around the selected comers of the tumor or biopsy site. Sentinel lymphoscintigraphy was performed 16-20 hours before surgery. Sentinel nodes were marked on the skin. An intraoperative gamma probe was used to confirm the sentinel lymph node location before biopsy. Most primary tumors were in the outer upper quadrant (52.3%), followed by the inner upper quadrant (17.0%), outer inferior quadrant (12.5%), central areolar area (11.4%), and inner inferior quadrant (6.8%). The nodal drainage patterns on 2-hour lymphoscintigraphy were as follows: axillary alone (76.1%), internal mammary nodes alone (1.1%), both axillary and internal mammary nodes (11.4%), and no drainage (11.4%). Internal mammary lymphatic drainage is related to tumor location in the inner quadrants of the breast. About 11.4% of all patients had poorly identified SLNs on lymphoscintigraphy within a 2-hour period, but there was improvement in the overall detection rate up to 95% by intraoperative gamma probe the next day. Preoperative lymphoscintigraphic mapping has value in providing individual lymphatic drainage patterns and tumor location that are important in the interpretation of the results of SLN biopsy during surgery.
The Kaohsiung journal of medical sciences 07/2005; 21(6):251-7. · 0.61 Impact Factor
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Clinical Nuclear Medicine 06/2004; 29(5):326. · 3.67 Impact Factor
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ABSTRACT: The graded shield technique was developed to increase the sentinel node detection rate by improving lymphoscintigraphic image contrast. In a 6-month period, 50 women with clinical suspicion of early stage breast cancer (T1 and T2 tumors) were enrolled in this study. The patients had a mean age of 47.2 +/- 10.3 years. A composite graded shield was constructed using three concentric layers of leaded plastic measuring 3 cm, 5 cm, and 7 cm each in diameter. The graded shield was designed with a movable Velcro backing for accurate positioning over the injection site. Images were acquired with a vertical angle dual-head gamma camera using an established injection procedure developed at our institution. The rate of detection of sentinel lymph nodes using lymphoscintigraphic mapping improved from 74% (37/50 patients) to 96% (48/50) using the graded shield (p < 0.05). In addition to the increased detection rate, our technique also increased the number of nodes detected and improved visualization of the adjacent lymphatic basin. By enhancing nodal contrast, we have demonstrated that the graded shield technique is an effective method for improving the rate of sentinel node detection.
The Kaohsiung journal of medical sciences 07/2003; 19(7):339-44. · 0.61 Impact Factor
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ABSTRACT: The actual relationship between the interval change of myocardial thallium 201 (Tl-201) radioactivity in the infarct area and the pattern of Q-wave regression is still unknown. This study was conducted to evaluate their relationship after acute myocardial infarction (AMI).
A total of 30 patients who had a first Q-wave AMI (11 without Q-wave regression and 19 with Q-wave regression) were retrospectively included. Two sets of 12-lead surface electrocardiograms and Tl-201 myocardial perfusion images were obtained 0 to 2 months and 14 to 84 months after the AMI event, respectively. The acute/subacute redistribution Tl-201 radioactivity was similar between the patients with and those without Q-wave regression. However, the patients with Q-wave regression had higher chronic redistribution Tl-201 radioactivity than those without Q-wave regression. Moreover, the patients with Q-wave regression presented a higher gradient in the redistribution Tl-201 radioactivity between the chronic and acute/subacute images than those without Q-wave regression.
This study supports the role of functional recovery of stunning and/or hibernating myocardium in the disappearance of Q waves after AMI.
Journal of Nuclear Cardiology 11(2):165-70. · 2.67 Impact Factor
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ABSTRACT: Spontaneous intracranial hypotension (SIH), by defini-tion, is spontaneous and without any obvious cause. The exact pathogenesis of SIH is still not clear. However, an occult cerebrospinal fluid (CSF) leak is considered as the cause of most if not all SIH. A 38-year-old woman with postural headache and low CSF pressure was reported in this article. The 99m Tc-diethyltri-aminepentacetic acid (DTPA) radionuclide cisternogra-phy (RNC) was performed and showed accumulation of radiotracer in the extra-arachnoid space over upper portion of thoracic spine. Besides, the indirect signs of early appearance of urinary bladder radioactivity on the 30-min image and poor migration of radiotracer over the cerebral convexities on the 24-h image were also noted. RNC is able to detect and localize the site of CSF leak and is useful as an initial diagnostic study of choice in SIH.
