Annals of Nuclear Medicine (v.25, #10)
The molecular imaging approach to image infections and inflammation by nuclear medicine techniques by Alberto Signore; Andor W. J. M. Glaudemans (681-700).
Inflammatory and infectious diseases are a heterogeneous class of diseases that may be divided into infections, acute inflammation and chronic inflammation. Radiological imaging techniques have, with the exception of functional MRI, high sensitivity but lack in specificity. Nuclear medicine techniques, by contrast, allow the in vivo detection in humans of different physiologic and pathologic phenomena and offer noninvasive tools to detect early pathophysiological changes before anatomical changes occur. In this review, we highlight the role of nuclear medicine in inflammation/infection with emphasis on molecular imaging for in vivo histological characterization of affected tissues for diagnostic purposes and follow-up of therapies. We also describe the clinical indications of all available radiopharmaceuticals in the light of the newly available guidelines.
Keywords: Inflammation; Infection; Molecular imaging; Nuclear medicine; Pathophysiology; Radiopharmaceuticals
Impact of FDG-PET/CT in the management of lymphoma by Shingo Baba; Koichiro Abe; Takuro Isoda; Yasuhiro Maruoka; Masayuki Sasaki; Hiroshi Honda (701-716).
Since the introduction of 67Gallium-citrate 30 years ago, nuclear medicine has played an important role in the evaluation of malignant lymphoma. During that time, several radiotracers were evaluated as potential alternatives for the diagnosis of lymphoma, but the introduction of 18F-fluorodeoxyglucose PET (FDG-PET) marked a major turning point. FDG-PET took over most of the role of gallium, and is now an essential tool in the diagnosis of lymphoma. FDG-PET is increasingly being used for assessment of the tumor staging prior to treatment, for evaluating the response to treatment, and for monitoring the early reactions to therapy to predict the final outcome. FDG-PET has been shown to have more accurate diagnostic capability than conventional CT and MRI for distinguishing the tumor necrosis and residual masses frequently seen after therapy in lymphoma patients without any clinical and biochemical manifestation. Malignant lymphoma is the first disease for which FDG-PET was adopted as a tool for response assessment in the international standard criteria. However, lymphoma does not always display a clear high uptake, and there are some pitfalls in assessing the response to therapy. This review will highlight the most important applications of FDG-PET in lymphoma, focusing on the advantages and pitfalls of this imaging, and past and ongoing efforts to standardize the use of FDG-PET, particularly in response to assessment and therapy monitoring.
Keywords: Malignant lymphoma; Response assessment of lymphoma; FDG-PET/CT in lymphoma; Pretreatment staging of lymphoma; Therapy monitoring of lymphoma
Animal tumor models for PET in drug development by Jun Toyohara; Kiichi Ishiwata (717-731).
Positron emission tomography (PET) is being increasingly applied to animal tumor models due to the need for proof-of-concept testing and preclinical efficacy studies of anticancer agents. Regardless of the nature of an experiment, investigators should carefully select a suitable animal tumor model as part of the experimental design. This review introduces sources of information and the guiding principles regarding applicability of various animal tumor models for PET in anticancer agent development especially for small animals.
Keywords: Animal tumor models; Positron emission tomography; Drug development; Anticancer agent
A modified method of 3D-SSP analysis for amyloid PET imaging using [11C]BF-227 by Tomohiro Kaneta; Nobuyuki Okamura; Satoshi Minoshima; Katsutoshi Furukawa; Manabu Tashiro; Shozo Furumoto; Ren Iwata; Hiroshi Fukuda; Shoki Takahashi; Kazuhiko Yanai; Yukitsuka Kudo; Hiroyuki Arai (732-739).
Three-dimensional stereotactic surface projection (3D-SSP) analyses have been widely used in dementia imaging studies. However, 3D-SSP sometimes shows paradoxical results on amyloid positron emission tomography (PET) analyses. This is thought to be caused by errors in anatomical standardization (AS) based on an 18F-fluorodeoxyglucose (FDG) template. We developed a new method of 3D-SSP analysis for amyloid PET imaging, and used it to analyze 11C-labeled 2-(2-[2-dimethylaminothiazol-5-yl]ethenyl)-6-(2-[fluoro]ethoxy)benzoxazole (BF-227) PET images of subjects with mild cognitive impairment (MCI) and Alzheimer’s disease (AD).The subjects were 20 with MCI, 19 patients with AD, and 17 healthy controls. Twelve subjects with MCI were followed up for 3 years or more, and conversion to AD was seen in 6 cases. All subjects underwent PET with both FDG and BF-227. For AS and 3D-SSP analyses of PET data, Neurostat (University of Washington, WA, USA) was used. Method 1 involves AS for BF-227 images using an FDG template. In this study, we developed a new method (Method 2) for AS: First, an FDG image was subjected to AS using an FDG template. Then, the BF-227 image of the same patient was registered to the FDG image, and AS was performed using the transformation parameters calculated for AS of the corresponding FDG images. Regional values were normalized by the average value obtained at the cerebellum and values were calculated for the frontal, parietal, temporal, and occipital lobes. For statistical comparison of the 3 groups, we applied one-way analysis of variance followed by the Bonferroni post hoc test. For statistical comparison between converters and non-converters, the t test was applied. Statistical significance was defined as p < 0.05.Among the 56 cases we studied, Method 1 demonstrated slight distortions after AS of the image in 16 cases and heavy distortions in 4 cases in which the distortions were not observed with Method 2. Both methods demonstrated that the values in AD and MCI patients were significantly higher than those in the controls, in the parietal, temporal, and occipital lobes. However, only Method 2 showed significant differences in the frontal lobes. In addition, Method 2 could demonstrate a significantly higher value in MCI-to-AD converters in the parietal and frontal lobes.Method 2 corrects AS errors that often occur when using Method 1, and has made appropriate 3D-SSP analysis of amyloid PET imaging possible. This new method of 3D-SSP analysis for BF-227 PET could prove useful for detecting differences between normal groups and AD and MCI groups, and between converters and non-converters.
Keywords: 3D-SSP; Voxel-based; Amyloid; PET; BF-227
Myocardial washout rate of technetium-99m-sestamibi in the chronic phase predicts myocardial damage in patients with previous myocardial infarction by Kohei Ashikaga; Yoshihiro J. Akashi; Kihei Yoneyama; Keisuke Kida; Kengo Suzuki; Fumihiko Miyake (740-748).
This study aimed to clarify the correlation between the myocardial washout rate (WR) of technetium-99m hexakis 2-methoxy-isobutyl-isonitrile (99mTc-sestamibi) and cardiac enzyme levels in patients with acute myocardial infarction (AMI) 6 months after the onset.Sixty-one consecutive AMI patients (mean age, 66.2 ± 9.7 years) who underwent percutaneous coronary intervention (PCI) on admission were enrolled. Creatinine kinase MB isoenzyme (CK-MB) levels were measured every 3 h. 99mTc-sestamibi myocardial scintigraphic images were obtained at the early (30 min) and delayed (4 h) phases after tracer injection for calculating heart-to-mediastinum (H/M) ratios and global WRs at 2 weeks (0 M) and 6 months (6 M) after the onset of AMI. Regional WRs in the culprit lesions (culprit WR) and the extent score (ES) and severity score (SS) of myocardial damage were also calculated.PCI was performed 8.3 ± 7.7 h after AMI onset. At 6 M, the early H/M ratio (p = 0.04), delayed H/M ratio (p = 0.02), global WR (p = 0.01), culprit WR (p = 0.002), and delayed ES (p = 0.008) were alleviated. At 0 M, the peak CK-MB level correlated with the delayed H/M ratio (p = 0.003), global WR (p = 0.003), culprit WR (p < 0.001), early ES (p = 0.03), delayed ES (p = 0.01), early SS (p = 0.001), and delayed SS (p < 0.001). At 6 M, the peak CK-MB level correlated with the delayed H/M ratio (p < 0.001), global WR (p = 0.005), culprit WR (p = 0.001), early ES (p = 0.001), delayed ES (p < 0.001), early SS (p < 0.001), and delayed SS (p < 0.001).These results demonstrated that 99mTc-sestamibi WR in the chronic phase as well as that in the acute phase reflects the extent of initial myocardial damage in AMI patients after PCI. Moreover, it might indicate the myocardial condition in the clinical course.
Keywords: 99mTc-sestamibi; The washout rate; Myocardial infarction; The chronic phase
Treatment of autonomously functioning thyroid nodules at a single institution: radioiodine therapy, surgery, and ethanol injection therapy by Yukiko Yano; Kiminori Sugino; Junko Akaishi; Takashi Uruno; Keiko Okuwa; Hiroshi Shibuya; Wataru Kitagawa; Mitsuji Nagahama; Kunihiko Ito; Koichi Ito (749-754).
The purpose of this study was to clarify the efficacy of radioiodine (RI) therapy in Japanese patients with autonomously functioning thyroid nodules (AFTNs).We performed a retrospective analysis to assess the management of AFTN patients. Thyroid lobectomy was performed to treat toxic adenoma (TA) patients, and total thyroidectomy to treat toxic multinodular goiter (TMNG) patients. RI therapy was administered in the form of a single dose (500 MBq) of isotope in the outpatient clinic. Percutaneous ethanol injection therapy (PEIT) was performed under ultrasound guidance.Of the total 205 patients, consisting of 159 TA and 46 TMNG patients, 99 underwent surgery, 50 received RI therapy, and 56 received PEIT. Remission of thyrotoxicosis was achieved in all of the patients who were treated surgically. Hypothyroidism was documented in six of the 72 patients who were treated surgically other than by total thyroidectomy. Remission of thyrotoxicosis was observed in 43 of the 50 patients who were treated by RI therapy. Nine TA patients developed hypothyroidism during the follow-up period after RI therapy. Several PEIT sessions were required to achieve a remission of thyrotoxicosis. Remission of thyrotoxicosis was achieved in 29 of the 56 patients treated by PEIT, and thyrotoxicosis recurred in 17 these 56 patients.Surgery is the treatment of choice for large nodules and nodules that are resistant to other treatments, because it allows prompt control of thyrotoxicosis. RI therapy is a safe and effective means of controlling thyrotoxicosis in AFTN patients. We conclude that RI therapy is the treatment of choice for definitive treatment of AFTN patients who do not have local compression symptoms.
Keywords: AFTN; RI therapy; Thyroid
Evaluation of organ-specific glucose metabolism by 18F-FDG in insulin receptor substrate-1 (IRS-1) knockout mice as a model of insulin resistance by Chao Cheng; Akinobu Nakamura; Ryogo Minamimoto; Kazuaki Shinoda; Ukihide Tateishi; Atsushi Goto; Takashi Kadowaki; Yasuo Terauchi; Tomio Inoue (755-761).
Insulin resistance (IR) is a physiological condition in which the body produces insulin but does not result in a sufficient biological effect. Insulin resistance is usually asymptomatic but is associated with health problems and is a factor in the metabolic syndrome. The aim of the present study is to clarify organ-specific insulin resistance in normal daily conditions using [18F]-2-fluoro-2-deoxy-d-glucose ([18F]-FDG).The biodistribution of [18F]-FDG was examined in insulin receptor substrate-1 (IRS-1) knockout mice, an animal model of skeletal muscle insulin resistance, and C57BL/6J (wild-type) mice with and without insulin loading. Mice received 0.5 MBq of [18F]-FDG injected into the tail vein, immediately followed by nothing (control cohorts) or an intraperitoneal injection of 1.5 mU/g body weight of human insulin as an insulin loading test. Blood glucose concentrations for all of the experimental animals were assessed at 0, 20, 40, and 60 min post-injection. The mice were subsequently killed, and tissue was collected for evaluation of [18F]-FDG biodistribution. The radioactivity of each organ was measured using a gamma counter.In the absence of insulin, the blood glucose concentrations of wild-type mice (132 ± 26 mg/dl) and IRS-1 knockout mice (134 ± 18 mg/dl) were not significantly different. Blood glucose concentrations decreased following insulin administration, with lower concentrations in wild-type mice than in knockout mice at 20, 40, and 60 min. A statistically significant difference in [18F]-FDG uptake between wild-type mice and IRS-1 knockout mice was confirmed in the heart, abdominal muscle, and femoral muscle. With insulin loading, [18F]-FDG uptake in the heart, back muscle, and abdominal muscle was significantly increased compared to without insulin loading in both wild-type mice and knockout mice.Our results showed that IR significantly affected [18F]-FDG uptake in the heart in normal daily conditions. IR was associated with decreased [18F]-FDG uptake in the heart and was readily observed in the absence of insulin loading. [18F]-FDG-positron emission tomography (PET) could be a useful tool for evaluating insulin resistance in images by investigating tissue-specific differences in [18F]-FDG uptake.
Keywords: Insulin resistance; Glucose metabolism; Insulin receptor substrate-1 (IRS-1); Insulin receptor substrate-1 (IRS-1) knockout mouse; [18F]-FDG
Tc-99m-BrIDA hepatobiliary (HIDA) scan has a low sensitivity for detecting biliary complications after orthotopic liver transplantation in patients with hyperbilirubinemia by L. Olivia Hopkins; Eyob Feyssa; Afshin Parsikia; Kamran Khanmoradi; Radi Zaki; Stalin Campos; Victor Araya; Huyen Tran; Jorge Ortiz (762-767).
Tc-99m-BrIDA hepatobiliary scans are noninvasive tests for detecting biliary leaks and obstructions. However, there is low sensitivity and specificity in patients with hyperbilirubinemia. Biliary complications (BC) are the Achilles heel of orthotopic liver transplantation (OLT). We questioned whether hyperbilirubinemia in liver transplant recipients rendered HIDA scanning less dependable.HIDA findings were compared to endoscopic retrograde cholangiopancreatography, laparotomy, and clinical course. Results were categorized as follows: true positive (TP), true negative (TN), false positive (FP), false negative (FN), or nondiagnostic/inconclusive. We searched for variables associated with erroneous or nondiagnostic tests which we defined as all examinations determined to be FP, FN and/or nondiagnostic/inconclusive.Thirty-four patients underwent a HIDA scan. The sensitivity and specificity were 70 and 100%. The sensitivity of HIDA improved to 100% in patients with a total bilirubin (TB) <5 mg/dl. Inconclusive and FN patients had a total bilirubin >5 mg/dl. One FN had a TB <5 mg/dl, but was determined inconclusive due to the roux-en-Y.HIDA scans performed when the total bilirubin was <5 mg/dl had a high sensitivity and specificity for detecting biliary complications after OLT. However, when the total bilirubin exceeded 5 mg/dl, the specificity was still 100% but the numbers of nondiagnostic/inconclusive and FN exams were increased.
Keywords: Hepatobiliary scan; HIDA scan; Hyperbilirubinemia; Orthotopic liver transplantation (OLT)
Novel algorithm for quantitative assessment of left ventricular dyssynchrony with ECG-gated myocardial perfusion SPECT: useful technique for management of cardiac resynchronization therapy by Keisuke Kiso; Akira Imoto; Yoshihiro Nishimura; Hideaki Kanzaki; Takashi Noda; Shiro Kamakura; Yoshio Ishida (768-776).
Cardiac resynchronization therapy (CRT) is the established treatment for patients with chronic and severe heart failure, and it has been reported that the presence of left ventricular (LV) dyssynchrony is one of the most important factors which predict positive response of this therapy. In the present study, we developed new software algorithm for quantitative assessment of LV dyssynchrony from ECG-gated myocardial perfusion SPECT (GMPS), and evaluated its utility for the management of CRT.Thirty-three patients with chronic severe heart failure were studied. GMPS was performed with 16 frame per-cardiac-cycle before and 6 months after CRT and LV end-diastolic volume, end-systolic volume (LVESV), ejection fraction (LVEF) were calculated by QGS software. We generated the time–activity curve per-cardiac-cycle in 4 myocardial segments by Fourier transform curve-fitting of the 16 serial count values, and measured the time from R-wave to the maximum-count point [time to end-systole (TES)] in each. For the evaluation of the degree of LV dyssynchrony, we used the maximum difference in TES (ΔTES) among the 4 segments which corrected for R–R time as dyssynchrony index (DI). Moreover, DI at baseline evaluated by GMPS was compared with the echocardiographic index of LV dyssynchrony; maximum difference of time to peak velocity (ΔTPV) evaluated by tissue Doppler imaging (TDI).DI before CRT showed a significant correlation with the LV function, such as LVEF, LVESV (DI vs. LVEF; r = 0.57, P < 0.0001. DI vs. LVESV; r = 0.64, P < 0.0001). The study subjects were divided into 2 groups, responder group (R-Gp) with LVEF increase >10% or LVESV decrease >10% and non-responder group (NR-Gp). DI before CRT was significantly larger in R-Gp than in NR-Gp (25.9 ± 22.2 vs. 10.8 ± 8.9, P = 0.01). In R-Gp, DI showed a significant decrease after CRT (25.9 ± 22.2 → 13.6 ± 10.9, P < 0.05). DI at baseline measured by GMPS correlated significantly with ΔTPV at baseline measured by TDI (r = 0.38, P < 0.05).This new algorithm for the estimation of LV dyssynchrony might be comparable to TDI, and contributes to the prediction and the evaluation for the response of CRT.
Keywords: Cardiac resynchronization therapy (CRT); Left ventricular dyssynchrony; ECG-gated myocardial perfusion SPECT
Additional value of FDG-PET to contrast enhanced-computed tomography (CT) for the diagnosis of mediastinal lymph node metastasis in non-small cell lung cancer: a Japanese multicenter clinical study by Kazuo Kubota; Koji Murakami; Tomio Inoue; Harumi Itoh; Tsuneo Saga; Susumu Shiomi; Jun Hatazawa (777-786).
This study was a controlled multicenter clinical study to verify the diagnostic effects of additional FDG-PET to contrast-enhanced CT for mediastinal lymph node metastasis in patients with operable non-small cell lung cancer (NSCLC).NSCLC patients with enlarged mediastinal lymph nodes (short diameter, 7–20 mm), confirmed using contrast-enhanced CT, were examined using FDG-PET to detect metastases prior to surgery. The primary endpoint was the accuracy for concomitantly used CT and FDG-PET showing the additional effects of FDG, compared with CT alone. The secondary endpoints were the clinical impact of FDG-PET on therapeutic decisions and adverse reaction from FDG administration. The images were interpreted by investigators at each institution. Moreover, blinded readings were performed by an image interpretation committee independent of the institutions. The gold standard was the pathological diagnosis determined by surgery or biopsy after PET, and patients in whom a pathological diagnosis was not obtained were excluded from the analysis.Among 99 subjects, the results for 81 subjects eligible for analysis showed that the accuracy improved from 69.1% (56/81) for CT alone to 75.3% (61/81) for CT + PET (p = 0.404). These findings contributed to treatment decisions in 63.0% (51/81) of the cases, mainly with regard to the selection of the operative procedure. The results of the image interpretation committee showed that the accuracy improved from 64.2% (52/81) (95% CI 52.8–74.6) for CT to 75.3% (61/81) (95% CI 64.5–84.2) for CT + PET. The accuracy for 106 mediastinal lymph nodes improved significantly from 62.3% (66/106) (95% CI 52.3–71.5) for CT to 79.2% (84/106) (95% CI 70.3–86.5) for CT + PET (p < 0.05). We found that no serious adverse drug reactions appeared in any of the 99 patients who received FDG, except for transient mild outliers in the laboratory data for two patients.The addition of FDG-PET to contrast-enhanced CT imaging for the staging of NSCLC improved the diagnostic accuracy for mediastinal lymph node metastasis. FDG-PET improved the precision of the staging of NSCLC and contributed to the surgical decisions.
Keywords: Mediastinal lymphnode; Lymphnode metastasis; Non-small cell lung cancer; FDG-PET; CT
Additional effects of FDG-PET to thin-section CT for the differential diagnosis of lung nodules: a Japanese multicenter clinical study by Kazuo Kubota; Koji Murakami; Tomio Inoue; Tsuneo Saga; Susumu Shiomi (787-795).
This study was a controlled multicenter clinical study on patients with peripheral lung nodules to verify the improvement in the diagnostic ability of FDG-PET when used in combination with thin-section CT (TS-CT).Patients with peripheral lung nodules (long maximal diameter: 10–30 mm) detected using CT were examined using TS-CT and FDG-PET for the differential diagnosis of benign or malignant lesions. The primary endpoint was the specificity of the results using a combination of TS-CT and FDG-PET, compared with the results for TS-CT alone. Images were interpreted by investigators at each institution. Blind readings were also performed by an independent image interpretation committee. The gold standard was a pathological diagnosis determined using a surgical or biopsy specimen obtained after PET; and the patients in whom a pathological diagnosis could not be obtained were diagnosed based on a follow-up TS-CT performed more than 6 months later. Adverse reactions to FDG were also evaluated.The blind reading results for 82 lesions in 81 subjects eligible for analysis among the 90 subjects included in the study showed a specificity of 91.2% (31/34) (95% CI: 76.3–98.1) for TS-CT + PET, compared with a specificity of 67.6% (23/34) (95% CI: 49.5–82.6) for TS-CT alone. The specificity was significantly improved by the addition of the PET findings (p < 0.05). The sensitivity improved from 89.6% (43/48) for TS-CT to 91.7% (44/48) for TS-CT + PET; the addition of PET increased the level of confidence in the diagnosis, but the difference was not significant. The results reported by the institutional investigators were not significantly different. No serious adverse reactions occurred, although two of the 90 subjects exhibited mild adverse reactions.The addition of FDG-PET to TS-CT for the differential diagnosis of benign or malignant peripheral lung nodules resulted in a significant improvement in specificity. Although a definitive diagnosis of lung nodules requires a histopathological or cytological examination, when combined with TS-CT, FDG-PET can provide additional diagnostic information and improve the specificity.
Keywords: Solitary pulmonary nodule; FDG-PET; CT; Multicenter study
Automated striatal uptake analysis of 18F-FDOPA PET images applied to Parkinson’s disease patients by I-Cheng Chang; Kun-Han Lue; Hung-Jen Hsieh; Shu-Hsin Liu; Chih-Hao K. Kao (796-803).
6-[18F]Fluoro-l-DOPA (FDOPA) is a radiopharmaceutical valuable for assessing the presynaptic dopaminergic function when used with positron emission tomography (PET). More specifically, the striatal-to-occipital ratio (SOR) of FDOPA uptake images has been extensively used as a quantitative parameter in these PET studies. Our aim was to develop an easy, automated method capable of performing objective analysis of SOR in FDOPA PET images of Parkinson’s disease (PD) patients.Brain images from FDOPA PET studies of 21 patients with PD and 6 healthy subjects were included in our automated striatal analyses. Images of each individual were spatially normalized into an FDOPA template. Subsequently, the image slice with the highest level of basal ganglia activity was chosen among the series of normalized images. Also, the immediate preceding and following slices of the chosen image were then selected. Finally, the summation of these three images was used to quantify and calculate the SOR values. The results obtained by automated analysis were compared with manual analysis by a trained and experienced image processing technologist.The SOR values obtained from the automated analysis had a good agreement and high correlation with manual analysis. The differences in caudate, putamen, and striatum were −0.023, −0.029, and −0.025, respectively; correlation coefficients 0.961, 0.957, and 0.972, respectively.We have successfully developed a method for automated striatal uptake analysis of FDOPA PET images. There was no significant difference between the SOR values obtained from this method and using manual analysis. Yet it is an unbiased time-saving and cost-effective program and easy to implement on a personal computer.
Keywords: FDOPA; Positron emission tomography (PET); Striatal-to-occipital ratio (SOR); Striatal uptake analysis; Parkinson’s disease
The value of 18F-FDG-PET/CT in the differential diagnosis of solitary pulmonary nodules in areas with a high incidence of tuberculosis by YaLun Li; Minggang Su; Fanglan Li; Anren Kuang; Rong Tian (804-811).
The purpose of this study was to evaluate 18F-FDG-PET, PET/CT, and CT in the diagnosis of benign or malignant solitary pulmonary nodules (SPNs) in areas with a high incidence of TB.Ninety-six patients with a SPN smaller than 30 mm were studied prospectively. PET/CT images were obtained 60 min after intravenous injection of 18F-FDG. The data obtained for each patient were analyzed and the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated and compared using χ2 test.The sensitivity, specificity, accuracy, PPV, and NPV in the diagnosis of SPN were 86.7, 72.2, 81.3, 83.9, and 76.5%, respectively, for CT and 88.3, 61.1, 79.1, 79.1, and 75.9%, respectively, for PET. Tuberculosis was responsible for 57.1% (8/14) of false-positives on PET. The sensitivity, specificity, accuracy, PPV, and NPV in the diagnosis of SPN were 96.7, 75.7, 88.5, 88.1, and 94.4% for PET/CT. The accuracy of PET/CT was higher than that of either CT or PET alone (P < 0.05).PET has a high false-positive rate in areas with a high incidence of TB; combined PET and CT (PET/CT) can improve the diagnostic accuracy in the differentiation of an SPN.
Keywords: 18F-FDG; Solitary pulmonary nodule; Positron emission tomography; Computed tomography
A black adrenal adenoma difficult to be differentiated from a malignant adrenal tumor by CT, MRI, scintigraphy and FDG PET/CT examinations by Masatoyo Nakajo; Masayuki Nakajo; Yoriko Kajiya; Atsushi Tani; Masashi Tsuruta; Satoshi Sugita; Shunsaku Fushitani; Yoshihisa Umekita (812-817).
Black adrenal adenoma (BAA) is an adrenal adenoma which contains lipofuscin and has a black or brown appearance. Preoperative diagnosis of BAA is difficult because it is diagnosed by pathologic findings. We report a case of an incidentally discovered non-hyperfunctioning BAA in the left adrenal gland of a 58-year-old man. It showed an oval lipid-poor mass, 3 cm × 2 cm in size on computed tomography (CT) and magnetic resonance imaging (MRI), no avid uptake of 131I-norcholesterol and 123I-meta-iodobenzylguanidine (MIBG) on scintigraphy, and intense avid uptake of 18F-fluorodeoxyglucose (FDG) on positron emission tomography–CT (PET/CT). FDG PET/CT showed that it was a hypermetabolic lesion, more intense than the activity of the liver, and the maximum standardized uptake value was 5.6 on 1-h early imaging and 8.3 on 2-h delayed imaging, suggesting a malignant tumor. BAA is a clinically rare benign adrenal adenoma, but it should be kept in mind that BAA may exhibit false-positive results for malignancy or inconclusive results for benignity with modern imaging modalities including CT, MRI, adrenal scintigraphy with radiolabelled cholesterol and radiolabelled MIBG, and FDG-PET like this case.
Keywords: Black adrenal adenoma; CT; MRI; Adrenal scintigraphy; FDG PET/CT
Utilization of nuclear medicine scintigraphy in Taiwan, 1997–2009 by Mao-Chin Hung; Wanhua Annie Hsieh; Peter Wushou Chang; Jeng-Jong Hwang (818-824).
To analyze the utilization of nuclear medicine scintigraphy in the Taiwanese population within the national health-care system between 1997 and 2009.Based on the Taiwan’s National Health Insurance Research Database of 1997–2009, a retrospective population-based analysis was conducted. Descriptive statistics and regression analysis were employed to analyze the frequencies and longitudinal trends in the utilization of diagnostic nuclear medicine procedures during the period. In addition, correlation analysis was applied to determine the correlated factors in the utility of nuclear medicine scintigraphy.The annual total nuclear medicine scintigraphy was estimated to be 256,389 on average in1997–2009 and 11.7 per 1,000 population over the period. The frequency had increased by 67% over the years, from 8.2 per 1,000 population in 1997 to 13.7 per 1,000 population in 2009. The most frequently performed procedures were whole-body bone scans (33.4% of total) and myocardial perfusion scans (29.4% of total), with 4,615 and 5,620 increments per year, respectively. Most patients were in the age group of 41–65 years old when taking examinations. In addition, male subjects were slightly more than female patients (51.5 vs. 48.5%). Furthermore, the frequencies of whole-body bone scans and PET scans were proportional to the incidences of cancers (correlation coefficients were 0.96 and 0.94, respectively).The utilization of nuclear medicine scintigraphy with the National Health Insurance system in Taiwan has been changed considerably in the past 13 years. Both whole-body bone scan and myocardial perfusion scan were performed most often with significantly increases. The trend of nuclear medicine scintigraphy may have potential impact on making health-care policy in Taiwan.
Keywords: Nuclear medicine scintigraphy; National Health Insurance