A 69-year-old woman was presented with progressed dysphagia, gastric soreness and weight loss during 2 months. She was performed abdomen x-ray, EGDS and abdomen CT. Abdomen x-ray demonstrated punctuate calcification on LUQ. EGDS showed an ulceroinfiltrative mass with bleeding on cardia to antrum of stomach. And CT showed diffuse gastric wall thickness with multiple calcifications. Biopsy of the stomach and esophagus during EGDS examination revealed an adenocarcinoma, with signet ring cell type, infiltrating the wall of the stomach and the distal esophagus. Then Bone scan was performed a few days later. It revealed intense uptake in LUQ, corresponding to the calcium containing neoplasm seen on the abdomen x-ray, EGDS and abdomen CT. And there was no evidence of any metastatic lesion and thyroid uptake on the bone scan. There are many reports about accumulation of the tracer in extraosseous lesion, but only a few literatures were reported about gastric calcification in stomach cancer. More over, no reports showed CT images. We are performed many diagnostic examinations and found well correlation between them. The reason of gastric calcification is considered with calcium deposition within extracellular space due to hemorrhage or necrosis. Other possibility offered to explain gastric calcification have been increased blood flow and/or increased neovascularity with capillary leaks of tracer, and specific enzymatic (phosphatases) receptor binding of tracer. So, it was happened ion exchange between intracellular calcium and phosphate groups of tracer.
Abdomen ; Adenocarcinoma ; Aged ; Biopsy ; Calcium ; Capillaries ; Cardia ; Deglutition Disorders ; Esophagus ; Extracellular Space ; Female ; Hemorrhage ; Humans ; Ion Exchange ; Necrosis ; Stomach ; Stomach Neoplasms ; Thyroid Gland ; Tomography, X-Ray Computed* ; Weight Loss

PURPOSE: The purpose of this study was to develop a small animal PET using dual layer phoswich detector to minimize parallax error that degrades spatial resolution at the outer part of field-of-view (FOV). MATERIALS AND METHODS: A simulation tool GATE (Geant4 Application for Tomographic Emission) was used to derive optimal parameters of small PET, and PET was developed employing the parameters. Lutetium Oxyorthosilicate (LSO) and Lutetium-Yttrium Aluminate-Perovskite (LuYAP) was used to construct dual layer phoswitch crystal. 8 X 8 arrays of LSO and LuYAP pixels, 2 mm X 2 mm X 8 mm in size, were coupled to a 64-channel position sensitive photomultiplier tube. The system consisted of 16 detector modules arranged to one ring configuration (ring inner diameter 10 cm, FOV of 8 cm). The data from phoswich detector modules were fed into an ADC board in the data acquisition and preprocessing PC via sockets, decoder block, FPGA board, and bus board. These were linked to the master PC that stored the events data on hard disk. RESULTS: In a preliminary test of the system, reconstructed images were obtained by using a pair of detectors and sensitivity and spatial resolution were measured. Spatial resolution was 2.3 mm FWHM and sensitivity was 10.9 cps/micro Ci at the center of FOV. CONCLUSION: The radioactivity distribution patterns were accurately represented in sinograms and images obtained by PET with a pair of detectors. These preliminary results indicate that it is promising to develop a high performance small animal PET.
Animals* ; Electrons* ; Lutetium ; Positron-Emission Tomography* ; Radioactivity

Cardiac neurotransmission imaging allows in vivo assessment of presynaptic reuptake, neurotransmitter storage and postsynaptic receptors. Among the various neurotransmitter, I-123 MIBG is most available and relatively well- established. Metaiodobenzylguanidine (MIBG) is an analogue of the false neurotransmitter guanethidine. It is taken up to adrenergic neurons by uptake-1 mechanism as same as norepinephrine. As tagged with I-123, it can be used to image sympathetic function in various organs including heart with planar or SPECT techniques. I-123 MIBG imaging has a unique advantage to evaluate myocardial neuronal activity in which the heart has no significant structural abnormality or even no functional derangement measured with other conventional examination. In patients with cardiomyopathy and heart failure, this imaging has most sensitive technique to predict prognosis and treatment response of betablocker or ACE inhibitor. In diabetic patients, it allow very early detection of autonomic neuropathy. In patients with dangerous arrhythmia such as ventricular tachycardia or fibrillation, MIBG imaging may be only an abnormal result among various exams. In patients with ischemic heart disease, sympathetic derangement may be used as the method of risk stratification. In heart transplanted patients, sympathetic reinnervation is well evaluated. Adriamycin-induced cardiotoxicity is detected earlier than ventricular dysfunction with sympathetic dysfunction. Neurodegenerative disorder such as Parkinson's disease or dementia with Lewy bodies has also cardiac sympathetic dysfunction. Noninvasive assessment of cardiac sympathetic nerve activity with I-123 MIBG imaging may be improve understanding of the pathophysiology of cardiac disease and make a contribution to predict survival and therapy efficacy.
3-Iodobenzylguanidine* ; Adrenergic Neurons ; Arrhythmias, Cardiac ; Cardiomyopathies ; Dementia ; Guanethidine ; Heart ; Heart Diseases ; Heart Failure ; Humans ; Lewy Bodies ; Myocardial Ischemia ; Neurodegenerative Diseases ; Neurons ; Neurotransmitter Agents ; Norepinephrine ; Parkinson Disease ; Prognosis ; Synaptic Transmission ; Tachycardia, Ventricular ; Tomography, Emission-Computed, Single-Photon ; Ventricular Dysfunction

Laparoscopic cholecystectomy can be performed safely in most patients with symptomatic cholelithiasis. Preoperative evaluation should assess the potential problems that affect the performance of laparoscopic cholecystectomy. Hepatobiliary scintigraphy or oral cholecystography can assess the gallbladder function and nonvisualization of gall bladder usually indicates acute or severe chronic cholecystitis. The purpose of this study was to evaluate the role of preoperative hepatobiliary scintigraphy or oral cholecystography in predicting the performance of laparoscopic cholecystectomy. The study group consists of 176 patients who underwent both hepatobiliary scintigraphy with Tc-99m DISIDA and oral cholecystography within one month before laparoscopic cholecystectomy. Nonvisualization of gallbladder was defined as persistent nonvisualization of gall- bladder until 4 hours on hepatobiliary scintigraphy or 12 hours on oral cholecystography. Among 176 patients, gallbladder was not visualized in 38 patients on hepatobiliary scintigraphy and 41 patients on oral cholecystography, Concordance rate between hepatobiliary scintigraphy and oral cholecystography was 89.2%. The conversion rate to open cholocystectomy was significantly higher in patients with nonvisualization of gallbladder than in patients with gallbladder visualization(15.8% vs 2.9% on hepatobiliary scintigraphy, 12.2% vs 3.7% on oral cholecystography: p<0.01 and p<0.05 respectively). The operative complication rate was also significantly higher in patients with nonvisualization of gallbladder (13.2% vs 2.9% on hepatobiliary scintigraphy, 14.6% vs 2.2% on. oral cholecystography : p<0.0l and p<0.001, respectively). Similarly, operation time was significantly prolonged in patients with nonvisualization of gall bladder (88.8+/-41.9min vs 62.5+/-23.6min on hepatobiliary scintigraphy : p<0.001, 89.4+/-41.3 min vs 61.8+/-22.8 min on oral cholecystography : p<0.001). It is concluded that nonvisualization of gallblader on hepato biliary scintigraphy or oral cholecystography is a valuable preoperative clincal risk factor in predicting increased conversion rate to open cholecystectomy, increased operative complication and prolonged operation time.
Adosterol* ; Cholecystectomy ; Cholecystectomy, Laparoscopic ; Cholecystitis ; Cholecystography ; Cholelithiasis ; Cushing Syndrome ; Gallbladder ; Humans ; Radionuclide Imaging* ; Risk Factors ; Urinary Bladder

131I-6beta-iodomethyl-19-norcholesterol(NP-59) has an advantage to assess adrenal dysfunction caused by adrenal cortical disorders. The aim of this study is to evaluate the clinical usefulness of NP-59 scintigraphy in each adrenral disease. Ten patients who did eleven NP-59 adrenal scintigraphies at Dong-A University Hospital from March 1990 to December 1996 were selected as the subject. Among the subject there were 5 cases of Cushing's syndrome, 2 cases of incidentaloma, 1 case of metastatic adrenal tumor, liver cirrhosis with hirsutism and hypertension respectively. Among 5 case of Cushing's syndrome, there were 2 cases of Cushing's disease, 2 cases of adrenal adenoma and 1 case of adrenal carcinoma. There are no disagreement between clinical diagnosis and scan finding in Cushing's syndrome. In 2 incidentaloma cases, even though one is interpretated as a functioning tumor, both of 2 cases could avoid unnecessary biopsy according to scintigraphy result. One case of hirsutism, clinically adrenal originated, revealed the normal scintigraphic hirsutism was extra-adrenal origin. One case of hypertension took the study to exclude the possibility of primary aldosteronism. Normal suppression scan finding revealed that primary aldosteronism did not exist in this case. In conclusion, NP-59 scintigraphy was very useful in diagnosis and differential diagnosis of Cushing's syndrome and it could avoid unnecessary biopsy in the incidental adrenal tumor.
Adenoma ; Adosterol ; Biopsy ; Cholecystectomy, Laparoscopic* ; Cholecystography* ; Cushing Syndrome ; Diagnosis ; Diagnosis, Differential ; Hirsutism ; Humans ; Hyperaldosteronism ; Hypertension ; Liver Cirrhosis ; Radionuclide Imaging*

The purpose of this study is to evaluate the diagnostic accuracy of various quantitative indices for the differentiation of benign from malignant primary soft tissue tumors by FDG-PET. A series of 32 patients with a variety of histologically or clinically confirmed benign (20) or malignant (12) soft tissue lesions were evaluated with emission whole body (5min/bed position) PET after injection of [18F]FDG. Regional 20min transmission scan for the attenuation correction and calculation of SUV was performed in 16 patients (10 benign, 6malignant) followed by dynamic acquisition for 56min. Postinjection transmission scan for the attenuation correction and calculation of SUV was executed in the other 16 patients (10 benign, 6 malignant). The following indices were obtained : the peak and average SUV (pSUV, aSUV) of lesions, tumor-to-background ratio acquired at images of 51 min p.i. (TBR51), tumor-to-background ratio of areas under time-activity curves (TBRarea) and the ratio between the activities of tumor ROI at 51 min p.i. and at the time which background ROI reaches maximum activity on the time-activity curves (T51/Tmax). The pSUV, aSUV, TBR51, and TBRarea, in malignant lesions were significantly higher than those in benign lesions. We set the cut-off values of pSUV, aSUV, TBR51, TBRarea and T51/Tmax for the differentiation of benign and malignant lesions at 3.5, 2.8, 5.1, 4.3 and 1.55, respectively. The sensitivity, specificity and accuracy were 91.7%, 80.0%, 84.4% by pSUV and aSUV, 83.3%, 85.0%, 84.4% by TBR51, 83.3%, 100%, 93.8% by TBRarea and 66.7%, 70.0%, 68.8% by Tsl/Tmax. The time-activity curves did not give additional information compared to SUV or TBR. The one false negative was a case with low-grade fibrosarcoma and all four false positives were cases with inflammatory change on histology. The visual analysis of FDG-PET also detected the metastatic lesions in malignant cases with comparable accuracy. In conclusion, all pSUV, aSUV, TBR51, and TBRarea are useful metabolic semi-quantitative indices with good accuracy for the differentiation of benign from malignant soft-tissue lesions.
Fibrosarcoma ; Humans ; Positron-Emission Tomography ; Sensitivity and Specificity

About one-third of radiologically indeterminate solitary pulmonary nodules (SPN) are eventually turned out to be malignant. It is very important to noninvasively determine whether the SPN is malignant or not for the decision of its way of management. PET imaging is highlighted by its unique ability of imaging the function and metabolism of cells. Glucose metabolism is increased in malignant transformed cells. We performed FDG-PET studies in patients who ha radiologi- cally indeterminate SPN and compared the findings with histologic diagnoses to assess the diagnostic accuracy in the detection of malignancy and to decide which parameter is the most suitable for clinical practice among peak SUV (pSUV), average SUV (aSUV), 50/10 ratio, and time-activity curve (TAC). Thirty patients were included in this study and the most useful parameter was pSUV. The sensitivity and specificity in the detection of malignant SPN using 3.5 as a cut off pSUV were both 87%. Interestingly, all 2 false-negative cases were bronch- ioloalveolar carcinoma on histologic examination. If these cases, which could be strongly suspected by CT findings, were excluded, the sensitivity of pSUV was 100%. In conclusion, PET imaging is very helpful for determining malignancy in indeterminate SPN and pSUV is a conveniently measurable parameter which is valuable for interpretation.
Diagnosis ; Glucose ; Humans ; Metabolism ; Positron-Emission Tomography ; Sensitivity and Specificity ; Solitary Pulmonary Nodule*

Gallium-67 scintigraphy is helpful in the assessment of active extrapulmonary sarcoidosis. Muscular involvement of sarcoidosis is often asymptomatic or nonspecific, and laboratory examinations do not provide convincing evidence of muscular involvement. We report a case of muscular sarcoidosis, which was detected by gallium-67 scintigraphy. In a patient who was suffering from fever and arthralgia of knee joint, gallium-67 scintigraphy showed mediastinal and hilar involvement of sarcoidosis with unexpected extensive muscular uptake. Magenetic resonance imaging revealed the detailed depiction of intramuscular infiltration of sarcoid granuloma. Gallium-67 scintigraphy is useful in detecting inflammatory muscular involvement of sarcoidosis as well as other multiorgan involvement.
Arthralgia ; Fever ; Granuloma ; Humans ; Knee Joint ; Magnetic Resonance Imaging* ; Radionuclide Imaging* ; Sarcoidosis*

Evaluation of dementia in patients with early symptoms of cognitive decline is clinically challenging, but the need for early, accurate diagnosis has become more crucial, since several medication for the treatment of mild to moderate Alzheimer' disease are available. Many neurodegenerative diseases produce significant brain function alteration even when structural imaging (CT or MRI) reveal no specific abnormalities. The role of PET and SPECT brain imaging in the initial assessment and differential diagnosis of dementia is beginning to evolve rapidly and growing evidence indicates that appropriate incorporation of PET into the clinical work-up can improve diagnostic and prognostic accuracy with respect to Alzheimer's disease, the most common cause of dementia in the geriatric population. In the fast few years, studies comparing neuropathologic examination with PET have established reliable and consistent accuracy for diagnostic evaluations using PET - accuracies substantially exceeding those of comparable studies of diagnostic value of SPECT or of both modalities assessed side by side, or of clinical evaluations done without nuclear imaging. This review deals the role of functional brain imaging techniques in the evaluation of dementias and the role of nuclear neuroimaging in the early detection and diagnosis of Alzheimer's disease.
Alzheimer Disease ; Brain ; Dementia* ; Diagnosis ; Diagnosis, Differential ; Functional Neuroimaging ; Humans ; Magnetic Resonance Imaging ; Neurodegenerative Diseases ; Neuroimaging ; Tomography, Emission-Computed, Single-Photon

Thallium-201 brain SPECT is utilized in the diagnosis of brain tumor especially in cases where CT or MRI findings alone cannot differentiate malignant lesion from benign. Recently we came across two cases of positive T1-201 brain SPECT in clinically suspected brain tumor patients that turned out to be hemorrhagic cerebral infarction instead on biopsy. The findings in these cases demonstrate that thallium-201 accumulation may occur by the breakdown of the blood-brain barrier and phagocytic cell infiltration in the liquefaction stage of infarction.
Biopsy ; Blood-Brain Barrier ; Brain ; Brain Neoplasms ; Cerebral Infarction* ; Diagnosis ; Humans ; Infarction ; Magnetic Resonance Imaging ; Phagocytes ; Tomography, Emission-Computed, Single-Photon