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Asia Oceania Journal of Nuclear Medicine & Biology - Volume:6 Issue: 2, Spring 2018

Asia Oceania Journal of Nuclear Medicine & Biology
Volume:6 Issue: 2, Spring 2018

  • تاریخ انتشار: 1397/03/22
  • تعداد عناوین: 16
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  • Maimoona Siddique*, Muhammad Khalid Nawaz, Humayun Bashir Pages 80-89
    Objective(s)
    This study sought to determine the diagnostic yield of SPECT/CT in localizing axillary sentinel lymph nodes (SLNs) in early breast cancer patients where planar scintigraphy (PS) was equivocal or negative.
    Methods
    Prospective analysis of early stage breast cancer patients with nonpalpable axillary nodes undergoing SLN localization prior to nodal sampling for axillary staging. PS findings were categorized as: Category A: non-visualization of SLN; Category B: unusual uptake location; Category C: equivocal uptake / difficult interpretation. The K-coefficient of Cohen was used to evaluate the correlation between PS and SPECT/CT results. PS and SPECT/CT images were interpreted separately, and SLN identification on each of the modalities was correlated to BMI (Body mass index) and peroperative radio guided results.
    Results
    Between April 2015 and January 2017, 1028 early breast cancer cases underwent sentinel lymphoscintigraphy. Of total, 134 (13%) patients underwent SPECT/CT in addition to PS. All were females with mean age of 48.15 years (range: 26-82 years). Right sided in 68, left in 64 and 2 with bilateral carcinoma. By TNM classification: 49 (37%) T1, 78 (58%) T2 and 7 (5%) had DCIS/Paget’s disease. Overall SLNs were detected on both PS and SPECT/CT in 60% cases. Of category A (n=54); 35/54 (64%) SLN localized on SPECT/CT; 32 were level-I; 2 Level-II; 1 Level-III nodes. In 19, SLN was not localized. Of category B (n=18), 5 had prior lumpectomy, SPECT/CT localized tracer uptake to 17 level-I sentinel nodes, 3 level-II and level III / IMC in 9. Of category C (n=62), 29 had prior lumpectomy. SPECT/CT confirmed SLN in all the cases. Radio-guided surgery confirmed SPECT/CT results. The correlation between the two techniques was low (K=0.34). Where PS was negative; SPECT/ CT localized nodes in statistically significant number of cases (P=0.01). PS identified SLN uptakes in 80/134 (60%) cases with a mean BMI of 21.6±4.8 kg/ m2 while SPECT/CT detected ‘‘hot’’ nodes in 115/134 (86%) cases with a mean BMI of 29.6±5.6 kg/m2. For overweight/obese patients (n=59) (BMI>25 kg/m2), PS failed to identify SLNs in 49 and SPECT/CT failed to do so in 18 (P
    Conclusion
    SPECT/CT has diagnostic yield and helps in precise SLN localization where planar imaging is negative or shows unusual site of uptake.
    Keywords: Sentinel node, SPECT-CT, Planar Scintigraphy, Breast cancer
  • Ryoto Otsuka, Yosuke Miyazaki, Narumi Kubo, Mio Kawahara, Jun Takaesu, Kazuki Fukuchi * Pages 90-96
    Objective(s)
    To appropriately use one-day myocardial perfusion imaging (MPI) with 99mTc radiopharmaceuticals (i.e. to avoid shine-through artifacts), injection doses need to be optimized and dose ratios between the 1st and 2nd scans should be maintained at ≥ 3. However, the current state of practice in Japan is unclear. Thus, the aim of this study was to clarify the details of MPI protocols using 99mTc radiopharmaceuticals in Japan.
    Methods
    A nationwide survey was conducted in June and July 2016. Questionnaires about stress MPI protocols using 99mTc radiopharmaceuticals were sent to 641 nuclear medicine facilities.
    Results
    Responses were received from 246 facilities. One-day protocols were used in 97.1% of the facilities. The most common injection dose ratio was 2.5. Only 18.2% of facilities achieved the recommended injection dose ratio. Stress-only protocols were performed in only 1.7% of facilities; the primary reasons for not performing stress-only protocols were as follows: 1) “The reading-physician cannot interpret the image just after the first scan,” and 2) “Preparation of radiopharmaceuticals and scan arrangements turn out to be complicated.”
    Conclusion
    Approximately 80% of nuclear medicine facilities do not follow the recommended injection dose ratio. Stress-only protocols are ideal, but are performed at very few facilities. Both optimization and standardization of stress MPI protocols using 99mTc radiopharmaceuticals are needed in Japan.
    Keywords: myocardial perfusion imaging, nuclear medicine, SPECT
  • Maryam Sahebari, Zahra Rezaieyazdi, Mandana Khodashahi, Bita Abbasi, Fazlollah Ayatollahi * Pages 97-107
    Objective(s)
    Systemic lupus erythematosus (SLE) is an autoimmune disease with a wide range of clinical manifestations. Cognitive dysfunction is one of the manifestations that could present prior to the emergence of any other neuropsychiatric involvements in SLE. Cognitive dysfunction is a subtle condition occurring with a high frequency. However, there is no data on the correlation of cognitive dysfunction with central nervous system (CNS) imaging findings, in particular single-photon emission computed tomography scan (SPECT) and functional MRI. We decided to perform a systematic review of brain SPECT and fMRI in SLE patients with cognitive dysfunction.
    Methods
    PubMed, Scopus, and Google Scholar databases were searched until April 2017 with the following keywords: “SLE OR systemic lupus erythematous OR lupus” AND “functional MRI OR functional magnetic resonance imaging OR fMRI OR SPECT or SCAN”. A total of 1,767articles were found. Two rheumatologists reviewed the articles and finally 14 articles were selected for the final systematic review.
    Results
    The fMRI and SPECT imaging techniques could provide valuable information regarding the SLE patients with cognitive dysfunction at the early stages of the disease.
    Conclusion
    Brain SPECT scan and fMRI are used as functional imaging tools in SLE. Both of these diagnostic modalities are sensitive in reflecting the subtle brain damages in SLE patients with cognitive dysfunction. Brain fMRI and SPECT scan could be significantly beneficial in the diagnosis and initial management of cognitive dysfunction in SLE. Nevertheless, prospective studies could be useful in confirming the application of these diagnostic modalities in the clinical setting.
    Keywords: Systemic lupus erythematosus, SPECT, functional magnetic resonance imaging, cognitive dysfunction
  • Ramin Ashrafpour, Narjess Ayati *, Ramin Sadeghi, Samira Zare Namdar, Nayyereh Ayati, Somaye Ghahremani, Seyed Rasoul Zakavi Pages 108-112
    Objective(s)
    TSH suppression by Levothyroxine consumption is a mainstay of thyroid cancer treatment. Tablet-splitting is a worldwide approach in dose adjustment in patients. However, it is highly recommended to evaluate the validity of tablet splitting for each distinctive drug by clinical trials before routinely using tablet halves in clinical practice. In this study we compared the effect of 150 μg dose of Levothyroxine by use of a100 and a 50 μg tablets or one and half 100 μg tablets in Differentiated thyroid cancer (DTC) patients.
    Methods
    One hundred DTC patients treated with one and half 100 μg Levothyroxine tablets were randomly divided into two groups. The first group continued taking medication as before and the second group received the same daily dose by taking one 100 and one 50 microgram Levothyroxine tablets. The mean changes in TSH and T3 levels and patients weight were compared between the groups.
    Results
    91 patients completed the study. Levothyroxine consumption pattern, age, gender distribution, weight and TSH levels were comparable between groups at the beginning of the study. The mean change of body weights, serum levels of T3 and TSH showed no significant difference between groups in different time points during the study (P>0.05).
    Conclusion
    This study showed similar efficacy of tablet splitting and two tablets administration for Levothyroxine; however, patients preferred two tablets at the end of the study. It can be concluded that tablet splitting can be used as an alternative way when the 50 μg tablet is not available.
    Keywords: Tablet splitting, Differentiated thyroid cancer, TSH, Levothyroxine, suppressive therapy
  • Kathy Willowson*, Hyunju Ryu, Price Jackson, Enid Eslick, Anita Singh, Dale Bailey Pages 113-119
    Objective(s)
    To investigate and compare quantitative accuracy of kidney absorbed dose measures made from both 2D and 3D imaging in patients receiving 177LuDOTATATE (Lutate) for treatment of neuroendocrine tumours (NETs).
    Methods
    Patients receiving Lutate therapy underwent both whole body planar imaging and SPECT/CT imaging over the kidneys at time points 0.5, 4, 24, and 96-120 hours after injection. Planar data were corrected for attenuation using transmission data, and were converted to units of absolute activity via two methods, using either a calibration standard in the field of view or relative to pre-voiding image total counts. Hand drawn regions of interest were used to generate time activity curves and kidney absorbed dose estimates in OLINDA-EXM. Fully quantitative SPECT data were generated using CT-derived corrections for both scatter and attenuation, before correction for dead time and application of a camera specific sensitivity factor to convert data to units of absolute activity. Volumes of interest were defined for kidney using the co-registered x-ray CT, before time activity curves and absorbed dose measures were generated in OLINDA-EXM, both with and without corrections made to the model for patient specific kidney volumes. Quantitative SPECT data were also used to derive dose maps through dose kernel convolution (DKC), which was treated as the gold standard.
    Results
    A total of 50 studies were analysed, corresponding to various cycles of treatment from 21 patients. Planar absorbed dose estimates were consistently higher than SPECT derived estimates by, on average, a factor of 3.
    Conclusion
    Quantitative SPECT is considered the gold standard approach for organ specific dosimetry however often relies on in house software. As such planar methods for estimating absorbed dose are much more widely available, and in particular, are often the only source of reference in previously published data. For the case of Lutate dosimetry, planar measures may lead to a three-fold increase in measures of kidney absorbed dose.
    Keywords: Lutate, Dosimetry, Kidney, NET
  • Keishin Morita, Akira Maebatake, Rina Iwasaki, Yuki Shiotsuki, Kazuhiko Himuro, Shingo Baba, Masayuki Sasaki * Pages 120-128
    Objective(s)
    The purpose of this study was to examine the optimal reconstruction parameters for brain dopamine transporter SPECT images obtained with a fan beam collimator and compare the results with those obtained by using parallel-hole collimators.
    Methods
    Data acquisition was performed using two SPECT/CT devices, namely a Symbia T6 and an Infinia Hawkeye 4 (device A and B) equipped with fan-beam (camera A-1 and B-1), low- and medium-energy general-purpose (camera A-2 and B-2), and low-energy high-resolution (camera A-3 and B-3) collimators. The SPECT images were reconstructed using filtered back projection (FBP) with Chang’s attenuation correction. However, the scatter correction was not performed. A pool phantom and a three-dimensional (3D) brain phantom were filled with 123I solution to examine the reconstruction parameters. The optimal attenuation coefficient was based on the visual assessment of the profile curve, coefficient of variation (CV) [%], and summed difference from the reference activity of the pool phantom. The optimal Butterworth filter for the 3D-brain phantom was also determined based on a visual assessment. The anthropomorphic striatal phantom was filled with 123I solution at striatum-to-background radioactivity ratios of 8, 6, 4, and 3. The specific binding ratio (SBR) of the striatum (calculated by the CT method) was used to compare the results with those of the parallel-hole collimators.
    Results
    The optimal attenuation coefficients were 0.09, 0.11, 0.05, 0.05, 0.11, and, 0.10 cm-1 for cameras A-1, A-2, A-3, B-1, B-2, and B-3, respectively. The cutoff frequencies of the Butterworth filter were 0.32, 0.40, and 0.36 cycles/cm for camera A, and 0.46, 0.4 , and 0.44 cycles/cm for camera B, respectively. The recovery rates of the SBRmean with camera A were 51.2%, 49.4%, and 45.6%, respectively. The difference was not statistically significant. The recovery rates of the SBR with camera B were 59.2%, 50.7%, and 50.8%, respectively. Camera B-1 showed significantly high SBR values. 3
    Conclusion
    As the findings indicated, the optimal reconstruction parameters differed according to the devices and collimators. The fan beam collimator was found to provide promising results with each device.
    Keywords: SPECT-CT, dopamine transporter, fan-beam collimator
  • Yoshito Kamiya, Satoru Ota, Yuta Tanaka, Kosuke Yamashita, Akihiro Takaki, Shigeki Ito * Pages 129-138
    Objective(s)
    We recently developed a new uptake index method for 123I-metaiodobenzylguanidine (123I-MIBG) heart uptake measurements by using planar images (radioisotope angiography and planar image) for the diagnosis of Lewy body disease (LBD), including Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). However, the diagnostic accuracy of the uptake index was approximately equal to that of the heart-to-mediastinum ratio (H/M) for the discrimination of the LBD and non-LBD patients. A simple and pain-free uptake index method using 123I-MIBG SPECT images by modifying the uptake index method may show better diagnostic accuracy than the planar uptake index method. We hypothesized that the development of a new uptake index method for the determination of 123I-MIBG using single-photon emission computed tomography (SPECT) imaging would provide a reliable and reproducible diagnostic tool for clinical application. Regarding this, the purpose of this study was to develop a new uptake index method with a simple protocol to determine 123I-MIBG uptake on SPECT.
    Methods
    The 123I-MIBG input function was determined from the input counts of the pulmonary artery, assessed by analyzing the pulmonary artery time-activity curves. The 123I-MIBG output function was obtained from 123I-MIBG SPECT counts on the polar map. The uptake index was calculated through dividing the output function by the input function (SPECT uptake method). For the purpose of the study, 77 patients underwent 123I-MIBG SPECT, with an average of 31.5 min after clinical assessment and injection of the tracer. The H/M values, as well as planar and SPECT uptake indices were calculated, and then correlated with clinical features.
    Results
    According to the results, values obtained for LBD were significantly lower than those for non-LBD in all analyses (P
    Conclusion
    The new 123I-MIBG SPECT quantification method, developed by the input counts of the pulmonary artery, clearly distinguished LBD from non-LBD. Therefore, this method may be appropriate for routine clinical study.
    Keywords: Iodine-123 metaiodobenzylguanidine, Lewy body disease, Quantification, Single-photon emission tomography
  • Hideo Onishi *, Takayuki Sakai, Osamu Shiromoto, Hizuru Amijima Pages 139-148
    Objective(s)
    The partial volume effect (PVE) of single-photon emission computed tomography (SPECT) on corpus striatum imaging is caused by the underestimation of specific binding ratio (SBR). A large ROI (region of interest) set using the Southampton method is independent of PVE for SBR. The present study aimed to determine the optimal ROI size with contrast and SBR for striatum images and validate the Southampton method using a three-dimensional mathematical cylinder (3D-MAC) phantom.
    Methods
    We used ROIs sizes of 27, 36, 44, 51, 61, 68, and 76 mm for targets with diameters 40, 20, and 10 mm on reference and processed images reconstructed using the 3D-MAC phantom. Contrast values and SBR were compared with the theoretical values to obtain the optimal ROI size.
    Results
    The contrast values in the ROI with diameters of 51 (target: 40 mm in diameter) and 44 (target: 20 mm in diameter) mm matched the theoretical values. However, this value did not correspond with the 10-mm-diameter target. The SBR matched the theoretical value with an ROI of > 44 mm in the 20-mm-diameter target; but, it was under- and overestimated under any other conditions.
    Conclusion
    These results suggested that an ROI should be 4-2 folds larger than the target size without PVE, and that the Southampton method was remarkably accurate.
    Keywords: specific binding ratio, partial volume effect, Southampton method
  • Yasukazu Kanai, Yoshinori Miyake, Jun Hatazawa* Pages 149-154
    Objective(s)
    Phenytoin is an antiepileptic drug that is used worldwide. The whole-body pharmacokinetics of this drug have been extensively studied using 11C-phenytoin in small animals. However, because of the limited production amounts that are presently available, clinical 11C-phenytoin PET studies to examine the pharmacokinetics of phenytoin in humans have not yet been performed. We aimed to establish a new synthesis method to produce large amounts of 11C-phenytoin to conduct human studies.
    Methods
    11C-methane was produced using an in-house cyclotron by the 14N (p, α) 11C nuclear reaction of 5 % of hydrogen containing 95 % of nitrogen gas. About 30 GBq of 11C-methane was then transferred to a homogenization cell containing Fe2O3 powder mixed with Fe granules heated at 320 0C to yield 11C-phosgene. Xylene, 1,4-dioxane, and diethylene glycol diethyl ether (DEGDEE) were investigated as possible reaction solvents.
    Results
    The ratio of 11C-phenytoin radioactivity to the total 11C radioactivity in the reaction vessel (reaction efficiency) was 7.5% for xylene, 11% for 1,4-dioxane, and 37% for DEGDEE. The synthesis time was within 45 min from the end of bombardment until obtaining the final product. The radioactivity produced was more than 4.1 GBq in 10 mL of saline at the end of synthesis. The specific activity of the product ranged from 1.7 to 2.2 GBq/μmol. The quality of the 11C-phenytoin injection passed all criteria required for clinical use.
    Conclusion
    The use of DEGDEE as a solvent enabled the production of a large amount of 11C-phenytoin sufficient to enable PET studies examining the human pharmacokinetics of phenytoin.
    Keywords: PET, Radiosynthesis, 11C-phenytoin, Radiopharmacy
  • Saeed Farzanefar, Rahman Etemadi, Mohammad Shirkhoda, Habibollah Mahmoodzadeh, Mostafa Erfani, Babak Fallahi, Mehrshad Abbasi, Narjess Ayati, Arman Hassanzadeh-Rad, Mohammad Eftekhari, Davood Beiki * Pages 155-160
    Objective(s)
    Malignant melanoma is the most lethal type of skin cancers with unfavorable prognosis. Alpha-MSH peptide analogues have a high affinity for melanocortine-1 (MC1) receptors on melanocytes over expressing in malignant melanoma cells. Pre-clinical studies have shown promising results for radiolabeled MSH imaging in this malignancy. The purpose of this study is to assess the diagnostic value of 99mTc-α-MSH imaging in malignant melanoma.
    Methods
    Twenty-one patients (13 men) with pathologically confirmed malignant melanoma with or without metastatic distribution were included in this study. 740-1110 MBq 99mTc-α-MSH was injected and whole body scans were performed 20, 120 and 240 minutes post injection and were assessed both qualitatively and semi-quantitatively using target (T) to background (BG) ratio.
    Results
    The T/BG ratio for the primary tumor bed was 2.51±2.26, 2.56±2.48 and 1.92±1.79 minutes in the whole body scans 20, 120 and 240 minutes post injection, respectively. The sensitivity, specificity, negative and positive predictive values were 75%, 80%, 50% and 92% for primary lesion and 25%, 100%, 68% and 100% for distant metastasis, respectively.
    Conclusion
    99mTc-α-MSH is a newly introduced agent for diagnosis of tumoral lesions in malignant melanoma. Our study showed a high sensitivity with this modality in primary lesions as well as lymph node involvements. However the detection rate was not high in distant metastasis. The preliminary results are promising especially as a new complementary imaging method in management of malignant melanoma.
    Keywords: Malignant melanoma, 99mTc-?-MSH, Melanocortine-1 receptor, Melanocyte stimulating hormone, Radiolabeled peptide
  • Raita Araki *, Ryosei Nishimura, Anri Inaki, Hiroshi Wakabayashi, Yasuhito Imai, Yoshikazu Kuribayashi, Kenichi Yoshimura, Toshinori Murayama, Seigo Kinuya Pages 161-166
    Objective(s)
    High-risk neuroblastoma is a childhood cancer with poor prognosis despite modern multimodality therapy. Internal radiotherapy using 131I-metaiodobenzylguanidine (MIBG) is effective for treating the disease even if it is resistant to chemotherapy. The aim of this study is to evaluate the safety and efficacy of 131I-MIBG radiotherapy combined with myeloablative high-dose chemotherapy and hematopoietic stem cell transplantation.
    Methods
    Patients with high-risk neuroblastoma will be enrolled in this study. A total of 8 patients will be registered. Patients will receive 666 MBq/kg of 131I-MIBG and after safety evaluation will undergo high-dose chemotherapy and hematopoietic stem cell transplantation. Autologous and allogeneic stem cell sources will be accepted. After engraftment or 28 days after hematopoietic stem cell transplantation, the safety and response will be evaluated.
    Conclusion
    This is the first prospective study of 131I-MIBG with high-dose chemotherapy and hematopoietic stem cell transplantation in Japan. The results will be the basis of a future nationwide clinical trial.
    Keywords: 131I-MIBG, Neuroblastoma, Hematopoietic stem cell transplantation, Prospective study protocol
  • Sara Shakeri, Soroush Zarehparvar Moghadam, Ramin Sadeghi, Narjess Ayati * Pages 167-170
    Sagliker syndrome is a rare form of renal osteodystrophy resulted from untreated secondary hyperparathyroidism. It is described by severe skeletal deformities, high level of PTH in patients with chronic renal failure, and deformed face. This paper reports a 44-year-old male patient with the mentioned characteristics. In addition to the unique clinical features, high levels of ALP and PTH hormones encouraged us to search for syndrome-like a disease, which clinically and paraclinically matched the Sagliker syndrome.
    This case highlights the importance of clinicians’ attention for early monitoring and appropriate treatment as it is shown to be effective in preventing irreversible complications such as soft tissue and bone abnormalities and cardiovascular impairment in patients with Sagliker syndrome. Therefore, considering the syndrome is recommended as one of the diagnostic hypothesis in young patients with renal insufficiency, secondary hyperparathyroidism, and skeletal deformities.
    Keywords: chronic renal failure, renal osteodystrophy, Sagliker syndrome, secondary hyperparathyroidism, skeletal deformity
  • Patrick Earl Amparado Fernando*, Patricia Amado Bautista Pages 171-178
    Parathyroid carcinoma is very rare, with only a few documented cases. Hence, metastatic lesions are infrequently documented on scintigraphic imaging. We present a case of a 63-year-old female presenting with elevated serum levels of ionized calcium and parathyroid hormone (PTH) who was referred to our department for a parathyroid scan with SPECT/ CT. Parathyroid scintigraphy showed a focus of increased 99mTc-sestamibi uptake corresponding to a solid mass with calcification in the inferior pole of the right thyroid lobe; tracer retention was noted on delayed images. Incidentally, focal uptake was also seen in a soft tissue mass on the 7th right rib. The patient soon underwent total thyroidectomy, with biopsy revealing parathyroid carcinoma on the right lobe. A bone scan done 7 months after surgery confirmed the presence of metastatic bone disease. The concomitant detection of intrathyroidal and extrathyroidal sestamibiavid masses on parathyroid scintigraphy should increase clinical suspicion of a metastatic process from parathyroid carcinoma.
    Keywords: Parathyroid carcinoma, SPECT-CT, 99mTc-sestamibi
  • Batool Al Balooshi *, Shabna Miyanath, Amr Elhennawy, Yaser Saeedi, Syed Hammad Tirmazy, Muhammed Muhasin, Bhavna Ray, Mouza Al Sharhan, Hassan Hotait, Yamina Houcinat, Tasnim Keloth Pages 179-185
    F-18 FDG is the most widely used tracer in molecular imaging and it is applied for many purposes mainly in malignant diseases. Incidental finding are common in FDG-PET/CT imaging and includes benign and malignant lesions. Among the rare tumors , adrenal oncocytomas are uncommon findings and incidental findings of thyroid malignancies are not rare. Oncocytoma is a rare adrenocortical tumor and majority of bulky adrenal tumors are benign with uncertain incident of malignancy. In this study, we are reporting a 37-year-old man with two incidental malignancies detected by FDG-PET-CT. He has no symptoms has no blood and hormonal abnormalities.
    The scan demonstrated intense heterogeneous FDG uptake within the bulky oval shaped lesion in the left adrenal gland. Accordingly, open adrenalectomy was performed and diagnosis of adrenocortical carcinoma oncocytic type was established. Furthermore, a focal FDG uptake was identified in the right thyroid lobe and histopathology findings were consistent with well-differentiated papillary thyroid cancer. FDG plays a great role in identifying primary rare lesions and also detection of incidental findings at unexpected sites.
    Keywords: F-18 FDG, adrenal mass, adrenocortical carcinoma, thyroid carcinoma, adrenal oncocytoma
  • Tadaki Nakahara * Page 186
  • Yuji Tsutsui * Pages 187-188