Recent Advances in Nuclear Cardiology

Lee, Won Woo The Korea Society of Nuclear Medicine 2016 핵의학 분자영상 Vol.50 No.3

Nuclear cardiology is one of the major fields of nuclear medicine practice. Myocardial perfusion studies using single-photon emission computed tomography (SPECT) have played a crucial role in the management of coronary artery diseases. Positron emission tomography (PET) has also been considered an important tool for the assessment of myocardial viability and perfusion. However, the recent development of computed tomography (CT)/magnetic resonance imaging (MRI) technologies and growing concerns about the radiation exposure of patients remain serious challenges for nuclear cardiology. In response to these challenges, remarkable achievements and improvements are currently in progress in the field of myocardial perfusion imaging regarding the applicable software and hardware. Additionally, myocardial perfusion positron emission tomography (PET) is receiving increasing attention owing to its unique capability of absolute myocardial blood flow estimation. An F-18-labeled perfusion agent for PET is under clinical trial with promising interim results. The applications of F-18 fluorodeoxyglucose (FDG) and F-18 sodium fluoride (NaF) to cardiovascular diseases have revealed details on the basic pathophysiology of ischemic heart diseases. PET/MRI seems to be particularly promising for nuclear cardiology in the future. Restrictive diseases, such as cardiac sarcoidosis and amyloidosis, are effectively evaluated using a variety of nuclear imaging tools. Considering these advances, the current challenges of nuclear cardiology will become opportunities if more collaborative efforts are devoted to this exciting field of nuclear medicine.

EDITORIAL : Molecular Pain Imaging by Nuclear Medicine: Where Does It Stand and Where Is It Going?

Min, Jung-Joon The Korea Society of Nuclear Medicine 2016 핵의학 분자영상 Vol.50 No.4

The Clinical Usefulness of $^{99m}Tc$ HMPAO Leukocyte/$^{99m}Tc$ Phytate Bone Marrow Scintigraphy for Diagnosis of Prosthetic Knee Infection: A Preliminary Study

Jung, Kyung Pyo,Park, Ji Sun,Lee, Ah Young,Choi, Su Jung,Lee, Seok Mo,Bae, Sang Kyun The Korea Society of Nuclear Medicine 2012 핵의학 분자영상 Vol.46 No.4

Purpose The preferred radionuclide imaging procedure for diagnosing prosthetic joint infection is combined radiolabeled leukocyte/$^{99m}Tc$ sulfur colloid bone marrow scintigraphy, which has an accuracy of over 90 %. Unfortunately, sulfur colloid is no longer available in South Korea. In this study, we evaluated the usefulness of $^{99m}Tc$ phytate, a substitute for $^{99m}Tc$ sulfur colloid, when combined with radiolabeled leukocyte scintigraphy in suspected prosthetic knee infections. Methods Eleven patients (nine women, two men; mean age $72{\pm}6$ years) with painful knee prostheses and a suspicion of infection underwent both $^{99m}Tc$ HMPAO leukocyte scintigraphy (LS) and $^{99m}Tc$ phytate bone marrow scintigraphy (BMS). The combined images were interpreted as positive for infection when radioactivity in the LS at the site of clinical interest clearly exceeded that of the BMS (discordant); they were interpreted as negative when the increased activity in the LS was consistent with an increased activity in the BMS (concordant). The final diagnosis was made with microbio-logical or intraoperative findings and a clinical follow-up of at least 12 months. Results Five of eleven patients were diagnosed as having an infected prosthesis. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of the combined LS/BMS were 100 %, 83 %, 83 %, 100 % and 91 %, respectively. Conclusion We find that combined $^{99m}Tc$ HMPAO LS/$^{99m}Tc$ phytate BMS shows comparable diagnostic performance to other studies utilizing sulfur colloid. Combined $^{99m}Tc$ HMPAO LS/$^{99m}Tc$ phytate BMS is therefore expected to be an acceptable alternative to combined radiolabeled LS/$^{99m}Tc$ sulfur colloid BMS for diagnosing prosthetic knee infections.

Tc-99m Ciprofloxacin SPECT of Pulmonary Tuberculosis

Lee, Min-Kyung,Yoon, Min-Ki,Hwang, Kyung-Hoon,Choe, Won-Sick The Korea Society of Nuclear Medicine 2010 핵의학 분자영상 Vol.44 No.2

Purpose Tc-99m ciprofloxacin is available for imaging infection. However, there has been no study on employing single photon emission computed tomography (SPECT) with using Tc-99m ciprofloxacin to image active pulmonary tuberculosis. Therefore, we conducted this study to assess the efficacy of Tc-99m ciprofloxacin SPECT for imaging active pulmonary tuberculosis. Methods Twenty-one participants were enrolled in this prospective study. They were divided into two groups according to the clinical and radiological assessment. Group one (Gr. 1) consisted of five normal volunteers and six patients with inactive pulmonary tuberculosis. Group two (Gr. 2) consisted of ten patients with active pulmonary tuberculosis. SPECT was performed 3 h after injecting 555 MBq (15 mCi) of Tc-99m ciprofloxacin. The findings of Tc-99m ciprofloxacin SPECT were interpreted by a nuclear medicine specialist and then the results were analyzed according to the patients' clinical and radiological classifications. Results The results of Tc-99m ciprofloxacin SPECT were as follows: eight true-positive cases, ten true-negative cases, one false-positive case and two false-negative cases. The sensitivity and specificity was 80.0% and 90.9%, respectively. The positive predictive value was 88.9% and the negative predictive value was 83.3%. Conclusions Tc-99m ciprofloxacin SPECT is feasible for imaging active pulmonary tuberculosis. It is a useful nuclear-imaging method for discriminating between the active and inactive tuberculosis states in patients with a past medical history of pulmonary tuberculosis.

Hibernoma: Intense Uptake on F18-FDG PET/CT

Kim, Jong Deok,Lee, Hang Woo The Korea Society of Nuclear Medicine 2012 핵의학 분자영상 Vol.46 No.3

Hibernoma is a rare benign but metabolically active tumor of brown fat origin, that can have cross-sectional imaging characteristics similar to those of other fat-containing tumors, such as lipomas and liposarcomas, and its presence can lead to false-positive interpretation by exhibiting increased F18-fluorodeoxyglucose (F18-FDG) activity. A 46-year-old woman was diagnosed with dermatofibrosarcoma protuberans underwent F18-FDG positron emission tomography/computed tomography (PET/CT) for detecting recurrence after excision. F18-FDG PET/CT showed incidental intense uptake in the back in addition to increased F18-FDG uptake at the previous lesion site. To our knowledge, this is the first case report of intense F18-FDG uptake in hibernoma in Korea.

Clinical Usefulness of $^{18}F$-fluoride Bone PET

Kang, Ji-Yeon,Lee, Won-Woo,So, Young,Lee, Byung-Chul,Kim, Sang-Eun The Korea Society of Nuclear Medicine 2010 핵의학 분자영상 Vol.44 No.1

Purpose $^{18}F$-fluoride bone positron emission tomography (PET) has been reported as a useful bone imaging modality. However, no clinical bone PET study had been performed previously in Korea. The authors investigated the usefulness of $^{18}F$-fluoride bone PET in Korean patients with malignant or benign bone disease. Methods Eighteen consecutive patients (eight women, ten men; mean age, $55{\pm}12$ years) who had undergone $^{18}F$-fluoride bone PET for the evaluation of bone metastasis (n=13) or benign bone lesions (n=5) were included. The interpretation of bone lesions on $^{18}F$-fluoride bone PET was determined by consensus of two nuclear medicine physicians, and final results were confirmed using combination of all imaging studies and/or clinical follow-up. The analysis was performed on the basis of lesion group. Results Thirteen patients with malignant disease had 15 lesion groups, among which seven were confirmed as metastatic bone lesions and eight were confirmed as non-metastatic lesions. $^{18}F$-fluoride bone PET correctly identified six of seven metastatic lesions (sensitivity, 86%), and seven of eight nonmetastatic lesions (specificity, 88%). On the other hand, five patients with benign conditions had five bone lesion groups; four were confirmed as benign bone diseases and the other one was confirmed as not a bone lesion. $^{18}F$-fluoride bone PET showed correct results in all the five lesion groups. Conclusions $^{18}F$-fluoride bone PET showed promising potential for bone imaging in Korean patients with malignant diseases as well as with various benign bone conditions. Therefore, further studies are required on the diagnostic performance and cost-effectiveness of $^{18}F$-fluoride bone PET.

Estimation of the Release Time from Isolation for Patients with Differentiated Thyroid Cancer Treated with High-dose I-131

Lee, Jai-Hyuen,Park, Seok-Gun The Korea Society of Nuclear Medicine 2010 핵의학 분자영상 Vol.44 No.4

Purpose Patients receiving high-dose I-131 to treat differentiated thyroid cancer are isolated from visitors to limit radiation exposure to reasonable levels. The appropriate isolation time is unclear and has not been reported in Korea. The purpose of this study was to estimate the isolation time and investigate the possibility of earlier release from isolation. Methods This study was a retrospective analysis of data from 71 patients (10 men and 61 women; mean age, $49{\pm}11.1\;y$) who received 3.7 GBq (47 patients), 5.55 GBq (23 patients), or 7.4 GBq (1 patient) of I-131 between January 2008 and December 2008. The radiation dose was measured with a fixed probe placed inside the isolation room. The total estimated dose equivalent (TEDE) to family members, the time required for the external dose rate to become <0.07 mSv/h, and the time required for whole-body retention to become <1.2 GBq were calculated. Results By the TEDE criterion (<5 mSv), 70 of 71 patients (98.6%) could have been released without isolation. By the external dose rate criterion, 10 of 71 (14.1%) and 60 of 71 patients (84.5%) could have been released without isolation and within 24 h, respectively. With whole-body retention criterion, 19 of 71 (26.8%) and 48 of 71 patients (67.6%) could have been released within 24 h and within 48 h, respectively. Conclusions Appropriate release times were estimated and compared using different criteria. Most patients could have been released without isolation or within 24 h of radiation treatment.

The Current Status and Future Perspectives of Nuclear Medicine in Korea

Lee, Myung-Chul,Oh, So-Won,Chung, June-Key,Lee, Dong-Soo The Korea Society of Nuclear Medicine 2010 핵의학 분자영상 Vol.44 No.2

Since the introduction of nuclear medicine in 1959, Korea accomplished a brilliant development in terms of both clinical practice and research activities, which was mainly due to the dedication of nuclear medicine specialists, consisting of physicians, technicians, and scientists, and strong support from the Korean Government. Now, Korea has 150 medical institutes, performing approximately 561,000 nuclear imaging procedures and 11.6 million in vitro studies in 2008, and ranked fourth in the number of presentations at the Annual Meeting of the Society of Nuclear Medicine (SNM) in 2008. The successful progress in this field has allowed Korea to focus on the international promotion of nuclear medicine, especially in the developing and underdeveloped countries. In consequence, the Asian Regional Cooperative Council for Nuclear Medicine (ARCCNM) was established in 2001, and Seoul hosted the 9th Congress of the World Federation of Nuclear Medicine and Biology (WFNMB) in 2006. In the future, Korea will strive to sustain its rate of advancement in the field and make every effort to share its progress and promote the exchange of scientific information at the international level.

Nonfunctioning Periurethral Paraganglioma Incidentally Detected by FDG PET/CT

Kim, Chul-Han,Oh, So-Won,Bae, Jeong-Mo,Jung, Kyeong-Cheon,Kim, Seung-Hyup,Kang, Keon-Wook,Lee, Dong-Soo The Korea Society of Nuclear Medicine 2011 핵의학 분자영상 Vol.45 No.2

Paragangliomas are extra-adrenal neuroendocrine tumors that are derived from neural crest cells. Among all the paragangliomas, those in a pelvic location are extremely rare. In addition, the prevalence of nonfunctioning paragangliomas is underestimated because of their clinical latency, and they are often underdiagnosed unless they cause symptoms. We report a case of a nonfunctioning periurethral paraganglioma that was incidentally detected by FDG PET/CT during regular follow-up after excision of a melanoma on the left thumb.

Incidental Bilateral Renal Oncocytoma in a Patient with Metastatic Carcinoma of Unknown Primary: a Pitfall on $^{18}F$-FDG PET/CT

Makis, William,Ciarallo, Anthony,Novales-Diaz, Javier-A.,Lisbona, Robert The Korea Society of Nuclear Medicine 2011 핵의학 분자영상 Vol.45 No.4

Bilateral renal masses are uncommon but can raise a strong suspicion of primary or secondary malignancy, especially during the initial work-up of an oncology patient. Renal oncocytomas are benign renal tumors that are commonly discovered incidentally on diagnostic imaging with a small percentage occurring bilaterally. Although $^{18}F$-FDG uptake in renal oncocytomas has been described, a case of a bilateral $^{18}F$-FDG-avid renal oncocytoma has not been previously reported in the literature. A variety of malignant causes of bilateral $^{18}F$-FDG positive renal masses are known, however it is important to include this benign etiology in the differential diagnosis. We report an unusual case of an incidental bilateral renal oncocytoma evaluated with contrast enhanced CT and $^{18}F$-FDG PET/CT.