外山 宏

INTRODUCTION Myocardial scintigraphy with I-123-15-(p-iodophenyl)-3-methyl pentadecanoic acid (I-123-BMIPP) is used to evaluate impaired fatty acid metabolism. B-type natriuretic peptide (BNP), which is secreted by the ventricular myocardium on stretching and/or pressure overload, is a useful cardiac biomarker. This study aimed to evaluate the usefulness of I-123-BMIPP imaging and serum BNP levels in patients with heart failure (HF). METHODS 113 patients with HF were enrolled. There were 68 patients with ischaemic heart disease (IHD) and 22 with overt HF. Cardiac scintigraphy was performed 7 +/- 3 days after admission, and heart-to-mediastinum (H/M) count ratios on early and delayed images and washout rates (WR) of I-123-BMIPP were recorded. Serum BNP levels were recorded on the day of I-123-BMIPP imaging. The ejection fraction (EF) was calculated just before cardiac scintigraphy using conventional echocardiography. RESULTS The mean BNP level and EF were 282 pg/mL and 47%, respectively, with significant correlation between them. The mean H/M count ratios on early and delayed images were 2.29 and 1.93, respectively, showing significant positive correlations with EF (r = 0.31, p = 0.0006). The WR was significantly correlated with EF (r = -0.36, p < 0.0001) and BNP levels (r = 0.33, p = 0.003), and mean WR was significantly higher in patients with overt HF compared to those without (p < 0.001). Patients with IHD had significantly higher EFs than those with non-IHD (p = 0.03). CONCLUSION The evaluation of impaired myocardial metabolism using I-123-BMIPP scintigraphy and serum BNP levels appears to be useful for the evaluation of severity of HF.

Objective: Following acute myocardial infarction (AMI) the area of myocardial perfusion and metabolism mismatch is designated as dysfunctional viable myocardium. 123I-beta-methyl iodophenyl pentadecanoic acid (BMIPP) is clinically very useful for evaluating myocardial fatty acid metabolism, and 99mTc-Tetrofosmin (TF) is a widely used tracer for myocardial perfusion. This study was designed to evaluate the degree of discrepancy between BMIPP and TF at the subacute state of AMI. Methods: Fifty-two patients (aged 59 ± 10 years mean 46 years) with AMI were enrolled, and all of them underwent percutaneous coronary intervention (PCI). Patients were classified according to ST-T change and PCI timing. 123I-beta-methyl iodophenyl pentadecanoic acid and TF cardiac scintigraphy were performed on 7 ± 3.5 days of admission using a dual headed gamma camera. Perfusion and fatty acid metabolism defect were scored on a 17 segments model. Results: The mean BMIPP defect score on early and delayed images were 16.67 ± 10.19 and 16.25 ± 10.40, respectively. The mean TF defect score was 10 ± 7.69. Defect score of BMIPP was significantly higher than that of the TF (P &lt 0.0001 95% CI 4.32-7.02), and there was a strong correlation between perfusion and metabolism defect score (r = 0.89, P &lt 0.00001). Forty-seven (90%) patients showed mismatched defect (BMIPP &gt TF), and 5 (10%) patients showed matched defect (BMIPP = TF). Mismatched defect score (MMDS) was significantly higher in patients with ST-segment elevation myocardial infarction (STEMI) than that of non-ST-segment elevation myocardial infarction (NSTEMI) (P &lt 0.041 95% CI 0.11-5.19). Conclusion: At the subacute state of AMI, most of the patients showed perfusion-metabolism mismatch, which represents the dysfunctional viable myocardium, and patients with STEMI showed higher mismatch. © 2012. Cardiological Society of India. All rights reserved.

Purpose: The incident at the Fukushima Daiichi nuclear power station in 2011 has again raised concerns with the public regarding radiation exposure, especially so in medical workers and patients undergoing treatment involving the use of radiation. Radioisotopes are currently used during sentinel node navigation surgery (SNNS) in operating rooms without radiation monitoring. To re-evaluate the safety issues, the potential effective dose (E poten) from 99mTc-tin (-Sn) colloid in breast cancer surgery was estimated and personal dose equivalents, H p(10) and H p(0.07), were measured during SNNS. Materials and methods: Seventeen breast cancer patients were enrolled. One day before SNNS, 99mTc-Sn colloid was injected around the tumor and radiation exposure rates were measured using survey meters. Personal dose equivalents for the surgical workers were measured. H p(10) and H p(0.07) for the body and H p(0.07) for the hands were recorded using semiconductor detectors and ring-type glass dosimeters. Results: The maximum E poten was 29 μSv per 74 MBq injection. The maximum H p(10) for the primary and assisting surgeons, nurse, and anesthetist was 3.7, 1.4, 0.3 and 0.6 μSv per SNNS, respectively. The maximum H p(0.07) for the hands was 100 μSv. Maximum radiocontamination 20 times higher than background (0.05 μSv/h) was detected in bloody gauze. Conclusion: The workers' radiation dose exposure from SNNS was not high, although radiation management such as a temporary cooling off period may be required. © Ejiri et al.

A 77-year-old woman presented with worsening cognitive impairment, nausea and vomiting. Computed tomography (CT) of the head revealed a high-density mass that symmetrically filled both lateral ventricles. Magnetic resonance imaging (MRI) showed an enhanced mass with T1 and T2 prolongation and restricted diffusion on diffusion weighted imaging (DWI). Diagnosis was delayed until a post-mortem examination, which revealed the mass as a primary central nervous system lymphoma (PCNSL). A high-intensity tumor on DWI with lateral ventricle involvement should raise the possibility of PCNSL. © Oie et al.

The objectives of the study were to quantitatively assess whole-brain CT Perfusion (CTP) data using an automatic region of interest (ROI) analysis program in order to distinguish between the degree of ischemia in the ischemic core and that in the penumbra and to assess the relationship between expansion of the area of infarction. The subjects were 20 patients with acute cerebral infarction. Whole-brain CTP was performed for all subjects using a 320-row area detector CT scanner. The penumbra* is defined as the region in which the CBV value is 2 mL/100 g or more and the ischemic core* is defined as the region in which the CBV value is less than 2 mL/100 g. The quantitative values of CTP parameters were automatically measured using the automatic ROIs analysis program. The Mann-Whitney U test was applied to differentiate between the ischemic core* and the penumbra*. The reduction in perfusion pressure in the penumbra* was smaller in the group with expansion of the area of infarction than in the group without expansion of the area of infarction. The difference in the median values between the penumbra* and the ischemic core* was larger in the group with expansion of the area of infarction than the group without expansion of the area of infarction. It is considered that the quantitative analysis method using whole-brain CTP may be useful for more accurately distinguishing between the ischemic core and the penumbra and for evaluating the risk of expansion of the ischemic core into the penumbra.

The transition of microglia from the normal resting state to the activated state is associated with an increased expression of peripheral benzodiazepine receptors (PBR). The extent of PBR expression is dependent on the level of microglial activation. A PBR ligand, [C-11]PK11195, has been used for imaging of the activation of microglia in vivo. We evaluated whether [C-11]PK11195 PET can indicate differences of microglial activation between no treatment and lipopolysaccharide (LPS) treatment in a rat artificial injury model of brain inflammation. On day 1, a small aliquot of absolute ethanol was injected into the rat right striatum (ST) to produce artificial brain injury. On day 3, MRI scans were performed to evaluate and select rats showing a similar degree of brain injury. Then LPS or vehicle was administered intraperitoneally. On day 4, PET scans were performed after a bolus injection of [C-11]PK11195. Eleven rats (7 LPS administered rats, 4 LPS non-administered rats) were evaluated. We used uptake ratios of the integral of right and left striatum from 0 to 60 min as an estimate of PBR distribution volume (V (60)). The number of activated microglia and mRNA expression of inflammatory cytokines (TNF alpha, IL-1 beta) were assessed by isolectin-B4 staining and RT-PCR, respectively. Right/left ST V (60) ratios of LPS group were significantly higher than those of non-LPS group (P < 0.03). Although there were no significant differences in the number of activated microglia between the two groups, LPS group showed higher expression of inflammatory cytokines (TNF alpha, IL-1 beta) than the non-treated group indicating that further activation was induced by LPS treatment. The results suggest that intensity of PBR signals in [C-11]PK11195 PET may be related to the level of microglial activation rather than the number in activated microglia at least in an artificial brain injury model.

Background: Myocardial fatty acid metabolic imaging with beta-methyl iodophenyl pentadecanoic acid (BMIPP) and perfusion imaging with tetrofosmin (TF) combined can predict post ischemic salvageable myocardium and persistent left ventricular (LV) dysfunction. This study was designed for the first time to assess systolic, diastolic and global LV dysfunction considering BMIPP and TF mismatched defect score (MMDS), and comparing this approach with the conventional Doppler echocardiography. Methods: Thirty four patients with first acute myocardial infarction (AMI) were enrolled, and all of them underwent percutaneous coronary intervention (PCI). BMIPP and Tetrofosmin (TF) scans were performed at 7+/-3.5 days of admission. Echocardiography was performed within 24 h of admission, at an interval of 1 and 3 months. MMDS was compared with systolic: ejection fraction (EF), wall motion score index (WMSI), fractional shortening (FS); diastolic: mitral valve deceleration time (MVDT), E/E', left atrial volume index (LAVI); combined systolic and diastolic parameter: left ventricular myocardial performance index (LVMPI). Results: A good correlation was observed between BMIPP and TF defect score (p<0.00001), and in 31 (91%) patients BMIPP defect score was higher than that of TF. The MMDS showed significant correlation with EF (r=-0.64, p=<0.00001), WMSI (r=0.61, p<0.0001), and FS(r=-0.65, p<0.00001), LAVI (r=-0.32, p<0.05), and LVMPI (r=0.37, p<0.02) during follow up echocardiography at 1 month. MVDT and E/E' did not correlate with MMDS. Conclusion: Perfusion-metabolism mismatched defect score was well correlated with the evolution of global left ventricular dysfunction following AMI evidenced from conventional Doppler echocardiography. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

The evolution of the oxidative metabolism of C-11 acetate parallels the recovery of left ventricular (LV) contraction following acute myocardial infarction (AMI). This study was designed to unravel, for the first time, the impact of the global washout rate (WR) of I-123-beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) on the recovery of LV function following AMI, as evidenced from conventional echocardiography. Twenty consecutive patients (age: 58 +/- 13 years; 16 males and 4 females) with ST-segment elevation myocardial infarction (STEMI) were enrolled and all of them underwent successful percutaneous coronary intervention (PCI). I-123-BMIPP cardiac scintigraphy was performed at 7 +/- 3 days after admission. The WR was calculated from the polar map and the regional BMIPP defect score was calculated using a 17 segment model. Echocardiography was performed within 24 h of admission and at 3 months to record the ejection fraction (EF), the wall motion score index (WMSI), the ratio of the mitral inflow velocity to the early diastolic velocity (E/E') and the myocardial performance index (MPI). The mean global WR of the BMIPP was 22.12 +/- 7.22%, and it was significantly correlated with the improvement of the WMSI (r = 0.61, P < 0.004). However, the relative changes of the EF, E/E' and MPI were not correlated with the WR. The BMIPP defect score (18 +/- 10) was significantly correlated with the WMSI on admission (r = 0.74, P = 0.0002), but the defect score was not correlated with the relative changes of any of the echocardiographic parameters. We proved that the WR of the BMIPP is a promising indicator of improvement of the LV wall motion (WMSI) following ST-segment elevation myocardial infarction and successful reperfusion.

I-123-beta-methyl-iodophenyl pentadecanoic acid (BMIPP) and Tc-99m-Tetrofosmin (TF) mismatch designated as stunned myocardium having both systolic and diastolic components. The degree of mismatch might reflect subsequent functional improvement, and this study was designed to unravel the impact of mismatched defect score (MMDS) on recovery of both systolic and diastolic function following acute myocardial infarction (AMI). Forty patients with recent AMI were recruited, and all of them underwent emergency percutaneous coronary intervention. Echocardiography and BMIPP and TF cardiac scintigraphy were performed on 7 +/- A 3 days of admission. Follow up echocardiography was performed after 3 months. MMDS were compared with the systolic [ejection fraction (EF) and wall motion score index (WMSI)] and diastolic [peak velocity of early diastolic filling of mitral inflow/peak early diastolic velocity of the mitral annulus(E/E') and left atrial volume index(LAVI)] parameters. BMIPP defect score was significantly higher than the TF defect score and there was a strong positive correlation between them (r = 0.90, P < 0.00001). Thirty-two (80%) patients showed mismatched defect and rest 8(20%) showed matched defect. Of 32 patients 24(75%), 22(69%), 19(59%), and 20(62.5%) showed improved EF, WMSI, E/E' and LAVI respectively. Conversely out of 8 only 2(25%), 1(12.5%), and 2(25%) patients showed improvement of EF, WMSI and LAVI, respectively. E/E' was not improved in patients with matched defect. MMDS were significantly correlated with the improvement of EF (r = -0.46, P = 0.002), WMSI (r = 0.41, P = 0.007), E/E' (r = 0.56, P < 0.0002), and LAVI (r = 0.44, P = 0.004). Mismatched defect score could predict the approximate amount of viable dysfunctional myocardium, and the degree of mismatch showed a significant correlation with the improvement of both systolic and diastolic function.

The Subcommittee on the Survey of Nuclear Medicine Practice in Japan has performed a nationwide survey of nuclear medicine practice every 5 years since 1982 to provide detailed information on its present status. Questionnaires were sent to all institutions known to the Japan Radioisotope Association to conduct nuclear medicine examinations. The questionnaires addressed the number and kind of nuclear medicine examinations performed as well as the kind and dose of the radiopharmaceuticals used during the month of June 2007. The annual number of total or specific examinations was then estimated. Of the institutions sent questionnaires, 1219 were for in vivo study, 49 for in vitro study, and 212 for positron emission tomography (PET) study. Of these, 92.2% provided answers. A total of 1569 gamma cameras were installed in 1119 institutions, of which 70% were dual-head cameras. The estimated total annual number of in vivo examinations expressed by the number of administered radiopharmaceuticals was 1.41 million, representing a decrease of 11.5% when compared with that of the previous survey (2002). The frequency of study with respect to single-photon emission computed tomography (SPECT) slightly increased to 42.3% from 39.9% in the previous survey. The most frequently performed scintigraphy was bone (38.3%), followed by myocardium (26.2%) and brain perfusion (14.1%). Brain perfusion scintigraphy slightly increased, whereas tumor scintigraphy decreased by one-half when compared with the previous survey. The most commonly used radiopharmaceutical for each scintigraphy was (99m)Tc-HMDP for bone, thallium-201 ((201)Tl)-chloride for myocardium, gallium-67 ((67)Ga)-citrate for tumor, and technetium-99m-ethylcysteinate dimmer ((99m)Tc-ECD) for brain. The number of PET institutes increased from 36 to 212. (18)F-fluorodeoxyglucose ((18)F-FDG)-PET dramatically increased 14.8-fold during the past 5 years. Radionuclide therapy also increased. (131)I therapy for thyroid cancer and hyperthyroidism was conducted yearly in 2373 and 4146 patients, respectively. A total of 13.1 million in vitro radioassays were carried out yearly, the number of which has been decreasing continuously since 1992. It was proved that the content of nuclear medicine practice in Japan has changed considerably in the past 5 years. Namely, (18)F-FDG-PET and radionuclide therapy increased. This report might be useful for understanding the present trends of nuclear medicine practice in Japan.

軽度認知機能障害(MCI)におけるアルツハイマー型認知症(AD)移行例と非移行例の3D-SSPおよびVSRAD所見の比較と、ADとレビー小体型認知症(DLB)について、3D-SSP、VSRAD、MIBG心筋シンチグラフィを用いた鑑別について述べた。3D-SSPの感度は50%、特異度は87.5%、VSRADの感度は62.5%、特異度は87.5%、両者の検査を組み合わせた場合は感度、特異度共に75%であった。内側側頭葉の萎縮は、VSRADのZ-scoreに有意差がみられなかった。これはDLB群における平均Z-scoreが比較的高値であったことに起因した。VSRADでもカットオフ値を上げることで3D-SSPに近い感度を示すが、いずれもDLBとADとでのオーバーラップがあり、MIBGを組み合わせた鑑別が望まれた。

Moyamoya disease is a vascular disease of unknown aetiology characterized by chronic progressive stenosis leading to occlusion of the supraclinoid internal carotid arteries and the proximal anterior and middle cerebral arteries along with abundant collateral vessel formation. Clinically the disease manifests with features of cerebral ischaemia including recurrent TIA's, headache, seizures or motor deficits. Characteristic angiographic features on MR angiography and conventional angiography confirm diagnosis. However, as the presence of complete arterial occlusion on angiography does not reliably predict haemodynamic impairment, single photon emission computed tomography (SPECT) is indicated for quantitative assessment of regional cerebral blood flow. SPECT is thus employed to detect regional perfusion instability prior to treatment and to determine the extent of improvement of functional perfusion after treatment. Affected patients with recurrent or progressive cerebral ischemic episodes and haemodynamic deficits SPECT findings require surgical management aimed at improving blood supply to the hypoperfused ischaemic cortical regions. The most commonly suggested revascularization procedure for children is encephaloduroarteriosynangiosis (EDAS). We describe an illustrative case report of 7-year-old boy who presented with sudden-onset of left sided herniparesis. Findings on CT, MRI and SPECT were consistent with a diagnosis of moyamoya disease with acute cerebral infarction. The boy underwent encephaloduroarteriosynangiosis twice with good outcome. Motor power in his left extremities improved from grade I to 3 without cognitive deficit. Postoperative MRI confirmed vascular patency while SPECT showed satisfactory cerebral perfusion consistent with his clinical outcome. We thus conclude that MRI and SPECT are invaluable tools in pre and postoperative evaluation of patients with moyamoya disease.

薬物治療による症状コントロールが不十分であり,精神症状が消褪しないレビー小体型痴呆(DLB)の症例(68歳女性)に対してmECTを施行し,劇的な症状の改善を得た.入院2週目よりmECTを隔日週3回2cool,型12回施行.5回目以降,上下肢の筋固縮は完全に消失.上肢の振戦は不変であったが,下肢および口唇部の振戦は消失した.8回目以降,発語量が増大し,仮面様顔貌も消失.10回目以降立位保持が可能となった.退院時には補助具使用による独歩可能であり,N-ADLも5点から44点とほぼ自立状態へと改善していた