論文

敗血症は全身性炎症性反応症候群(SIRS)に伴う急性肺障害(ALI/ARDS)の最も一般的な原因である.死亡率も高く発症早期から積極的な治療が重要と考えられる.今回,膿胸に合併した敗血症・ARDSに好中球エラスターゼ阻害剤が奏効した症例を経験したので報告する.患者は70歳,男性.陳旧性心筋梗塞(左室駆出率は33%)などにて近医通院中,膿胸を発症し当院紹介となった.トロッカーを挿入した直後に心室細動となったためACLSを開始した.電気的除細動を計8回施行した.敗血性ショックによるARDSが原因と考えられ,全身状態管理をするとともに好中球エラスターゼ阻害剤であるシベレスタットナトリウム投与を開始した.同剤投与後から肺機能の改善(PaO2/FIO2:54.3→138)を認めた.途中低心機能と低アルブミン血症のため輸液の慎重な管理を要したが,1ヵ月後には人工呼吸器から離脱した.2ヵ月半の入院の後,独歩にて自宅へ退院した.早期からの全身管理と好中球エラスターゼ阻害剤の使用が有用であったと思われる.(著者抄録)

© 2019 by the Society of Nuclear Medicine and Molecular Imaging. Calcification in a coronary artery is accepted as definite evidence of coronary atherosclerosis. The extent and density of calcification, as combined in the Agatston score, is associated with the risk of a patient experiencing a major acute coronary event. Atherosclerosis occurs because damaged endothelial cells allow low-density lipoprotein cholesterol (LDLc) to leak into subintimal tissue. Proteoglycans in subendothelial collagen have a high affinity for LDLc, retaining the lipoprotein cholesterol complex. As the endothelial damage is repaired, the subintimal LDLc is trapped. Retained LDLc induces an inflammatory response in the overlying endothelium, causing the endothelium to express chemotactic peptides. Chemotactic peptides attract circulating monocytes, which follow the concentration gradient, enter the tissue, and become tissue macrophages to phagocytize and digest the irritating LDLc in the atheroma. In the process of digesting LDLc, enzymes in the macrophages oxidize the LDLc complex. Oxidized LDL is toxic to macrophages; when present in sufficient quantity, it may cause death of macrophages, contributing to inflammation in the atheroma. In a necrotic inflammatory lesion, the regulatory mechanisms that control tissue concentrations of calcium and phosphorus are lost, allowing the solubility product of calcium phosphate to be exceeded, resulting in the formation of microscopic calcium-phosphate crystals. With ongoing inflammation, additional calcium-phosphate crystals are formed, which may aggregate. When these aggregated calcium phosphate crystals exceed 1 mm, the lesions become visible on clinical CT as coronary calcifications. Serial gated CT scans of the heart have demonstrated that once formed, CT-visible calcifications do not decrease significantly in size but may increase.

© 2019, American Society of Nuclear Cardiology. Background: Fluoride-18 sodium fluoride (18F-NaF) localizes in microcalcifications in atheroma. The microcalcifications may aggregate, passing the resolution threshold to visualize on computed tomography (CT). We evaluated serial NaF positron emission tomography (PET)-CT scans to determine the temporal relationship between vascular NaF uptake and CT evident calcification in the abdominal aorta. Methods: Prostate cancer patients who had at least 3 NaF PET-CT scans over at least 1.5 years were retrospectively enrolled. Regions of interest were traced in the abdominal aorta on both PET and CT images, excluding skeletal NaF activity. The maximum standardized uptake value (SUVmax) of NaF and the density and volume of calcium (exceeding 130 HU) were summed and divided by the number of slices to produce the SUVmax/slice and the mm3·slice−1 of calcium. Results: Of 437 patients, 45 patients met criteria. NaF uptake waxed and waned between scans, while the calcium volume plateaued or increased over time. NaF uptake correlated with calcium volume on the baseline scan (P =.60, <.0001†) and calcium volume increment, especially from 1.0 to 1.5 years (r =.79, P <.0001†). Patients with persistently high NaF uptake showed a higher calcium volume increment (0-1.5 years) than patients with low or transiently high NaF uptake. Conclusions: Abdominal aortic NaF uptake varied over time. NaF uptake on the baseline scans and high NaF uptake on the serial scans preceded an increase in calcium volume, especially by 1.0-1.5 years. Persistently high NaF uptake was associated with a greater increment in calcium volume than patients with transiently elevated or persistently low fluoride uptake.

Background: Despite the improvement of cardiac CT, right heart visualization remains challenging. Objective: We herein describe a new method, called the time-adjusted gradual replacement injection protocol. The aim of this study was to compare this protocol with the split-bolus injection protocol. Methods: Fifty-two patients who had undergone dual-source cardiac CT were retrospectively recruited. Twenty-six patients were injected by using the split-bolus injection protocol, and 26 patients were injected by using the time-adjusted gradual replacement injection protocol. For this method, we injected contrast medium for 10seconds at a flow rate of 0.07× body weight mL/s, then gradually replaced the contrast material with saline until 2 seconds before finishing the scans. The CT attenuation was measured in 4 chambers, the aorta, and the coronary arteries. The visualization of the anatomic structures and the occurrence and severity of streak artifacts were scored for the cardiac structures in the heart. For the analyses, either Welch t-test or Student t-test was performed. Results: In the right heart, the CT values and visualization scores were significantly higher in the time-adjusted replacement injection group than in the split-bolus injection group, whereas the artifact scores were comparable between the 2 groups. The CT values, visualization scores, and artifact scores of the left heart were not significantly different between the 2 groups. Conclusions: In this study, the time-adjusted gradual replacement injection protocol provided excellent attenuation for visualization of the right heart. This method may help toaccurately evaluate the right cardiac anatomy and thereby identify any potential diseases. © 2014 Society of Cardiovascular Computed Tomography.

We report a 59-year-old woman with type 2 diabetes mellitus (DM) complicated with smoldering myeloma and non-alcoholic steatohepatitis. A diagnosis of smoldering myeloma was made on the basis of elevation of IgA, M-protein (type:IgA-λ) and histological findings of bone marrow without bone lesion. As to liver dysfunction, anti-HBV, anti-HCV and a series of auto-immune antibody were negative. She had no alcohol drinking habit and histological findings showed pericellular fibrosis without fatty degeneration, suggesting liver cirrhosis due to non-alcoholic steatohepatitis (NASH). To date, there are no reports of cases with DM, NASH and myeloma. Particular attention may be necessary for these complications.

Currently, no three-dimensional reference data exist for the normal coccyx in the standing position on computed tomography (CT); however, this information could have utility for evaluating patients with coccydynia and pelvic floor dysfunction. Thus, we aimed to compare coccygeal parameters in the standing versus supine positions using upright and supine CT and evaluate the effects of sex, age, and body mass index (BMI) on coccygeal movement. Thirty-two healthy volunteers underwent both upright (standing position) and conventional (supine position) CT examinations. In the standing position, the coccyx became significantly longer and straighter, with the tip of the coccyx moving backward and downward (all p < 0.001). Additionally, the coccygeal straight length (standing/supine, 37.8 ± 7.1/35.7 ± 7.0 mm) and sacrococcygeal straight length (standing/supine, 131.7 ± 11.2/125.0 ± 10.7 mm) were significantly longer in the standing position. The sacrococcygeal angle (standing/supine, 115.0 ± 10.6/105.0 ± 12.5°) was significantly larger, while the lumbosacral angle (standing/supine, 21.1 ± 5.9/25.0 ± 4.9°) was significantly smaller. The migration length of the tip of the coccyx (mean, 7.9 mm) exhibited a moderate correlation with BMI (r = 0.42, p = 0.0163). Our results may provide important clues regarding the pathogenesis of coccydynia and pelvic floor dysfunction.

Saphenous veins (SVs) are frequently employed as bypass grafts. The SV graft failure is predominantly seen at the valve site. Avoiding valves during vein harvest would help reduce graft failure. We endeavored to detect SV valves, tributaries, and vessel size employing upright computed tomography (CT) for the raw cadaver venous samples and in healthy volunteers. Five cadaver legs were scanned. Anatomical analysis showed 3.0 (IQR: 2.0–3.0) valves and 13.50 (IQR: 10.00–16.25) tributaries. The upright CT completely detected, compared to 2.0 (IQR: 1.5–2.5, p = 0.06) valves and 9.5 (IQR: 7.5–13.0, p = 0.13) tributaries by supine CT. From a total of 190 volunteers, 138 (men:75, women:63) were included. The number of valves from the SF junction to 35 cm were significantly higher in upright CT than in supine CT bilaterally [upright vs. supine, Right: 4 (IQR: 3–5) vs. 2 (IQR:1–2), p < 0.0001, Left: 4 (IQR: 3–5) vs. 2 (IQR: 1–2), p < 0.0001]. The number of tributaries and vessel areas per leg were also higher for upright compared with supine CT. Upright CT enables non-invasive detection of SV valves, tributaries, and vessel size. Although not tested here, it is expected that upright CT may potentially improve graft assessment for bypass surgery.

【目的】(1)立位CTの物理特性の評価,(2)大血管と骨盤底への重力の影響を評価すること.【方法】ファントムを用いて立位CTと臥位CT,それぞれの物理特性の評価を行った.健常人ボランティアを対象に立位CTと臥位CTを同日に施行,大静脈と大動脈の面積と骨盤底の変化を評価した.【結果】立位CTと臥位CT両者の物理特性に有意差は見られなかった.仰臥位と比較して直立位では,上大静脈の面積は有意に小さく,横隔膜の高さでの下大静脈の面積に有意差は見られず,下大静脈下端部での面積は有意に大きくなった.一方,大動脈の面積に関しては姿勢による有意差は見られなかった.骨盤底は直立位で下降した.【結論】立位CTと臥位CTの性能はほぼ同等であり,立位CTは,人体に対する重力の影響を評価するのに有用であった.(著者抄録)

© 2018 American College of Cardiology Foundation Objectives: The purpose of this study was to evaluate the feasibility of imaging apoptosis in experimental ischemia-reperfusion model by technetium-99m (99mTc)-labeled Duramycin, and compare it to an established tracer, 99mTc-labeled Annexin-V, which has a relative disadvantage of high radiation burden to nontarget organs. Background: During apoptosis, the cell membrane phospholipids-phosphatidylserine (PS) and phosphatidylethanolamine (PE) are exposed and can be targeted by Annexin-V and Duramycin, respectively, for in vivo imaging. Identification of a reversible cell death process should permit therapeutic intervention to help reduce myocyte loss and left ventricle dysfunction. Methods: In a 40-min left coronary artery ischemia-reperfusion model in 17 rabbits, 7 mCi of 99mTc-labeled Duramycin (n = 10), 99mTc-linear Duramycin (a negative tracer control; n = 3), or 99mTc-Annexin-V (a positive tracer-control; n = 4) were intravenously administered 30 min after reperfusion. Of the 10 Duramycin group animals, 4 animals were treated with an antiapoptotic agent, minocycline at the time of reperfusion. In vivo and ex vivo micro–single-photon emission computed tomography (μSPECT) and micro-computed tomography (μCT) imaging was performed 3 h after reperfusion, followed by quantitative assessment of tracer uptake and pathological characterization. Fluorescent Duramycin and Annexin-V were injected in 4 rats to visualize colocalization in infarct areas in a 40-min left coronary artery occlusion and 30-min reperfusion model. Results: Intense uptake of Duramycin and Annexin-V was observed in the apical (infarcted) areas. The percent injected dose per gram uptake of Duramycin in apical region (0.751 ± 0.262%) was significantly higher than remote area in same animals (0.045 ± 0.029%; p < 0.01). Duramycin uptake was insignificantly lower than Annexin-V uptake (1.23 ± 0.304%; p > 0.01) but demonstrated substantially lower radiation burden to kidneys (0.358 ± 0.210% vs. 1.58 ± 0.316%, respectively; p < 0.001). Fluorescence studies with Duramycin and Annexin V showed colocalization in infarct areas. Minocycline treatment substantially resolved Duramycin uptake (0.354% ± 0.0624%; p < 0.01). Conclusions: Duramycin is similarly effective in imaging apoptotic cell death as Annexin-V with lower nontarget organ radiation. Clinical feasibility of apoptosis imaging with a PE-seeking tracer should be tested.