F-18 fluorodeoxyglucose (FDG) is a highly influential radiotracer that provides valuable information in many cancer types. However, the normal biodistribution of F-18 FDG is often variable and can be altered by intrinsic or iatrogenic factors. We report a case of diffuse symmetrically increased skeletal muscle uptake and relatively decreased hepatic uptake on F-18 FDG PET/CT in a 57-year-old female with pulmonary adenocarcinoma. Detailed clinical evaluation and retrospective radiologic evaluation revealed that she had been diagnosed with subacute thyroiditis 2 weeks ago. After 6 weeks, F-18 FDG distribution was normalized at the follow-up PET/CT study.
Adenocarcinoma ; Female ; Follow-Up Studies ; Humans ; Hyperthyroidism ; Middle Aged ; Muscle, Skeletal ; Positron-Emission Tomography and Computed Tomography ; Retrospective Studies ; Thyroiditis, Subacute

F-18 fluorodeoxyglucose (FDG) is a highly influential radiotracer that provides valuable information in many cancer types. However, the normal biodistribution of F-18 FDG is often variable and can be altered by intrinsic or iatrogenic factors. We report a case of diffuse symmetrically increased skeletal muscle uptake and relatively decreased hepatic uptake on F-18 FDG PET/CT in a 57-year-old female with pulmonary adenocarcinoma. Detailed clinical evaluation and retrospective radiologic evaluation revealed that she had been diagnosed with subacute thyroiditis 2 weeks ago. After 6 weeks, F-18 FDG distribution was normalized at the follow-up PET/CT study.

A 77-year-old male underwent open repair for a right indirect inguinal hernia and complained of right scrotal pain on the third postoperative day. Color Doppler imaging revealed decreased blood flow with heterogeneous hypoechogenicity in the right testis. A Tc-99m pertechnetate testicular scan showed diffuse hyperemia and increased uptake in the right scrotum. Additional SPECT/CT revealed a photon defect in the right testicle with increased uptake in the peri-testicular area. A subsequent operation revealed a large hematoma in the right spermatic cord and consequent right testicular infarction, and right orchiectomy was performed.
Aged ; Diagnosis ; Hematoma ; Hernia, Inguinal ; Herniorrhaphy ; Humans ; Hyperemia ; Infarction ; Male ; Orchiectomy ; Scrotum ; Sodium Pertechnetate Tc 99m ; Spermatic Cord ; Testis

The purpose of this study was to evaluate the value of fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) for detecting the recurrence of gastric cancer. We performed a retrospective review of 139 consecutive patients who underwent PET/CT and contrast-enhanced abdominal CT (CECT) for surveillance of gastric cancer after curative resection. Recurrence of gastric cancer was validated by histopathologic examination for local recurrence or serial imaging study follow-up with at least 1 yr interval for recurrence of distant metastasis form. Twenty-eight patients (20.1%) were confirmed as recurrence. On the patient based analysis, there was no statistically significant difference in the sensitivity, specificity and accuracy of PET/CT (53.6%, 84.7%, and 78.4%, respectively) and those of CECT (64.3%, 86.5%, and 82.0%, respectively) for detecting tumor recurrence except in detection of peritoneal carcinomatosis. Among 36 recurrent lesions, 8 lesions (22.2%) were detected only on PET/CT, and 10 lesions (27.8%) only on CECT. PET/CT had detected secondary malignancy in 8 patients. PET/CT is as accurate as CECT in detection of gastric cancer recurrence after curative resection, excepting detection of peritoneal carcinomatosis. Moreover, additional PET/CT on CECT could improve detection rate of tumor recurrence and provide other critical information such as unexpected secondary malignancy.
Aged ; Female ; Fluorodeoxyglucose F18/*diagnostic use ; Humans ; Male ; Middle Aged ; Neoplasm Recurrence, Local/*diagnosis/radiography/radionuclide imaging ; Positron-Emission Tomography/*methods ; Radiopharmaceuticals/*diagnostic use ; Retrospective Studies ; Sensitivity and Specificity ; Stomach Neoplasms/*diagnosis/pathology/surgery ; Tomography, X-Ray Computed/*methods

A 50-yr-old man presented with intermittent hemoptysis and was diagnosed small cell lung cancer. 18F-FDG PET/CT for staging demonstrated extensive hypermetabolic lesions throughout the skeleton and liver. Interestingly, skeletal muscles of limbs, mediastinum, bowel, and especially brain showed very low FDG uptake. Because of some characteristics in common with super scan on skeletal scintigraphy, this case could be considered as 'metabolic super scan'.
Carcinoma, Small Cell/complications/radionuclide imaging ; Fluorine Radioisotopes/diagnostic use ; Fluorodeoxyglucose F18/*diagnostic use ; Hemoptysis/complications/radionuclide imaging ; Humans ; Liver Neoplasms/diagnosis/secondary ; Lung Neoplasms/complications/radionuclide imaging ; Male ; Middle Aged ; *Positron-Emission Tomography ; Radiopharmaceuticals/*diagnostic use

Radioiodine ablation therapy has been considered to be a standard treatment for patient with differentiated thyroid cancer after total thyroidectomy. Patients may need to be hospitalized to reduce radiation exposure of other people and relatives from radioactive patients receiving radioiodine therapy. Medical staffs, nursing staffs and technologists sometimes hesitate to contact patients in radioiodine therapy ward. The purpose of this paper is to introduce radiation dosimetry, estimate radiation dose from patients and emphasize the safety of radiation exposure from patients treated with high dose radioiodine in therapy ward. The major component of radiation dose from patient is external exposure. However external radiation dose from these patients treated with typical therapeutic dose of 4 to 8 GBq have a very low risk of cancer induction compared with other various risks occurring in daily life. The typical annual radiation dose without shielding received by patient is estimated to be 5 to 10 mSv, which is comparable with 100 to 200 times effective dose received by chest PA examination. Therefore, when we should keep in mind the general principle of radiation protection, the risks of radiation exposure from patients are low and the medical personnel are considered to be safe from radiation exposure.
Humans ; Medical Staff ; Nursing Staff ; Radiation Protection ; Radiometry ; Thorax ; Thyroid Neoplasms ; Thyroidectomy

In this paper, the authors intended to summarize briefly the features of lymphoma with regard to (18)F-FDG PET for assessment of tumor response to therapy, to describe why assessment of treatment response should be performed, to review what method so far has been used in monitoring treatment response, to discuss what limitations of morphologic imaging criteria for assessing tumor response are, in compared with (18)F-FDG PET, and to introduce recently proposed criteria for assessing tumor response in malignant lymphoma. And also the authors emphasize the need to understand the characteristics of diagnostic performance of (18)F-FDG PET in several clinical settings in order to interpret (18)F-FDG PET results appropriately, and to encourage the use of interval likelihood ratio to enhance clinical implications of test results which, in turns, allows referring physicians to understand the meaning of interpretation with easy. Until recently, treatment response has been assessed according to the morphologic criteria. Metabolic imaging with (18)F-FDG PET was adopted to have important role for treatment assessment in IWC+PET criteria proposed recently by IHP. To accomplish this role, we should perform and interpret (18)F-FDG PET according to IWC+PET criteria. It is important for referring physicians to understand the various limitations of (18)F-FDG PET and pitfalls in PET interpretation, and to understand that clinical information are needed by nuclear medicine physicians to optimize the interpretation of (18)F-FDG PET.
Lymphoma ; Nuclear Medicine ; Positron-Emission Tomography

PURPOSE: This study was performed to investigate the clinical significance of reverse redistribution (RR) phenomenon detected on delayed Tc-99m tetrofosmin myocardial single photon emission computed tomography (SPECT) in patients with acute myocardial infarction after revascularization. MATERIALS AND METHODS: A Tc-99m tetrofrosmin myocardial SPECT was performed in 67 consecutive patients after revascularization for acute myocardial infarction. Myocardial SPECT imaging was performed for early imaging at 40 min and for delayed imaging at 180 min after reinjection at myocardial stress. Regional myocardial uptakes were scored by 4-point scoring in the left ventricular wall divided into 17 segments. Reverse redistribution was defined as an increase of more than 2 point in the activity score on the delayed image. Follow-up myocardial SPECT and coronary angiography (CAG) were performed 9 months later. RESULTS: On myocardial SPECT performed following revascularization, RR was observed in 100 of all 319 segments (31%) and in 43 patients (64%). The abnormalities of perfusion and regional wall motion were more severe in the patients with RR compared to those without RR (p<0.05). On follow-up myocardial SPECT, the myocardial perfusion, regional wall motion, and myocardial thickness were significantly improved in the patients with RR (p<0.05) however, these changes were not significant in those without RR. There was no significant difference between the patients with RR and those without RR in the occurrence of restenosis on CAG. CONCLUSIONS: In patients with acute myocardial infarction, the regions showing the RR phenomenon on delayed Tc-99m tetrofosmin SPECT may reflect viable myocardium and indicate recovery of salvaged myocardium.
Angioplasty ; Coronary Angiography ; Follow-Up Studies ; Humans ; Myocardial Infarction ; Myocardial Perfusion Imaging ; Myocardium ; Perfusion ; Tomography, Emission-Computed, Single-Photon

Soft tissue uptake of Tc-99m labeled bone seeking agents, such as Tc-99m 3,3-diphosphono-1,2-propanedicarboxylic acid (DPD), is commonly seen in clinical practice, even though bone scintigraphy is mainly used to detect bone disease. However, gastric uptake of bone agents in patients with gastric cancer is very rare. And it has been reported that calcified gastric adenocarcinoma appears in only about 5% of all gastric cancer. We report a rare case of bone scintigraphy, single photon emission computed tomography and computed tomography fusion images that demonstrated diffuse gastric uptake of Tc-99m DPD in a patient with advanced gastric cancer.
Stomach Neoplasms/*metabolism ; Stomach/*metabolism ; Radiopharmaceuticals/*pharmacokinetics ; Organotechnetium Compounds/diagnostic use/*pharmacokinetics ; Male ; Humans ; Diphosphonates/diagnostic use/*pharmacokinetics ; Bone and Bones/*radionuclide imaging ; Aged

The purpose of this volunteer study was to investigate whether pretreatment with UDCA before the administration of 99mTc DISIDA affects the biliary excretion of the DISIDA, and whether it can shorten the total imaging time. Ten young, healthy volunteers (eight males, two females, mean age: 26.3 +/- 2.1 years) participated in the study. Hepatobiliary scintigraphies were performed twice per volunteer within three days, for the control and the UDCA-pretreated studies. In the control study, the gallbladder (GB) was observed first in four cases and the intestine was observed first in another four cases; in contrast, in the UDCA challenge study, the GB was observed first in eight cases. The quantitative results for the factors related to the GB differed significantly between the control and challenge studies. When the subjects were pretreated with UDCA, the time duration until visualization of the GB was shortened, and the maximum activity of the GB became more intense. In conclusion, UDCA pretreatment before hepatobiliary scintigraphy can shorten the total imaging time for evaluating functional obstructions of the cystic duct and increase the specificity of the process.
Adult ; Biliary Tract/*radionuclide imaging ; Female ; Humans ; Liver/*radionuclide imaging ; Male ; Radionuclide Imaging/*methods ; Radiopharmaceuticals/*pharmacokinetics ; Technetium Tc 99m Disofenin/*pharmacokinetics ; Ursodeoxycholic Acid/*pharmacology