外山 宏

我々は心臓サルコイドーシス疑いの74例において,「2016年版心臓サルコイドーシスの診療ガイドライン」における組織診断・臨床診断を真として,FDG-PET/CTの診断精度を検討した.さらにFDG-PET/CTと同時期に心臓造影MRIを施行した33例において,ガドリニウム造影剤を用いた遅延造影(LGE)所見を検討した.全74例中31例が本症の診断基準を満たし,38例が診断基準を満たさず,残り5例は心限局性サ症の疑診例であった.診断基準を満たした31例を真とすると,FDGPET/CTによる感度,特異度,正診率,陽性的中率,陰性的中率は,それぞれ90%,87%,88%,85%,92%であった.心臓造影MRIを同時期に施行した33例において,FDG-PET/CT陽性の20例中16例でLGE陽性,FDG-PET/CT陰性の13例中8例でLGE陽性であった.心サ症疑い患者におけるFDG-PET/CTの診断精度は非常に良好であった.さらに心臓MRIの遅延造影所見を加えることは,本症の活動性や線維化の診断に有用であった.(著者抄録)

Nephron-sparing surgery has been proven to positively impact the postoperative quality of life for the treatment of small renal tumors, possibly leading to functional improvements. Laparoscopic partial nephrectomy is still one of the most demanding procedures in urological surgery. Laparoscopic partial nephrectomy sometimes results in extended warm ischemic time and severe complications, such as open conversion, postoperative hemorrhage and urine leakage. Robot-assisted partial nephrectomy exploits the advantages offered by the da Vinci Surgical System to laparoscopic partial nephrectomy, equipped with 3-D vision and a better degree in the freedom of surgical instruments. The introduction of the da Vinci Surgical System made nephron-sparing surgery, specifically robot-assisted partial nephrectomy, safe with promising results, leading to the shortening of warm ischemic time and a reduction in perioperative complications. Even for complex and challenging tumors, robotic assistance is expected to provide the benefit of minimally-invasive surgery with safe and satisfactory renal function. Warm ischemic time is the modifiable factor during robot-assisted partial nephrectomy to affect postoperative kidney function. We analyzed the predictive factors for extended warm ischemic time from our robot-assisted partial nephrectomy series. The surface area of the tumor attached to the kidney parenchyma was shown to significantly affect the extended warm ischemic time during robot-assisted partial nephrectomy. In cases with tumor-attached surface area more than 15 cm(2), we should consider switching robot-assisted partial nephrectomy to open partial nephrectomy under cold ischemia if it is imperative. In Japan, a nationwide prospective study has been carried out to show the superiority of robot-assisted partial nephrectomy to laparoscopic partial nephrectomy in improving warm ischemic time and complications. By facilitating robotic technology, robot-assisted partial nephrectomy will be more frequently carried out as a safe, effective and minimally-invasive nephron-sparing surgery procedure.

The Subcommittee on the Survey of Nuclear Medical Practice in Japan has performed a nationwide survey of nuclear medicine practice every 5 years since 1982 to survey contemporary nuclear medicine practice and its changes over the years. The subcommittee sent questionnaires, including the number and category of examinations as well as the kind and dose of the radiopharmaceuticals during the 30 days of June 2012, to all the nuclear medicine institutes. The total numbers for the year 2012 were then estimated. A total of 1,167 institutes responded to the survey, including the 14 in vitro assay institutes and 266 PET centers. The recovery rate was 92 %. The number of gamma cameras installed was 1,425 in total, with 9 % decrease in 5 years. Dual-head cameras and hybrid SPECT/CT scanners accounted for 84 and 10.5 %, respectively. The number of single-photon tracer studies in 2012 was 1.15 million which means decrease in 19 % in 5 years and 29 % in 10 years. All but cerebral perfusion study and sentinel lymphoscintigraphy have decreased. Bone scintigraphy was a leading examination (38.7 %), followed by cardiac studies (29.4 %) and cerebral perfusion study (18.5 %) in order. SPECT studies showed an increase from 42.3 to 47.2 %. PET centers have also increased from 212 to 295, as compared to the last survey. The 135 PET centers have installed one or two in-house cyclotrons. PET studies showed 25.5 % increase in 5 years, with oncology accounting for 96.3 %. F-18-FDG accounted for 98.2 % (505,990 examinations). PET examinations using C-11-methionine have been increasing, with 3,352 examinations in 2012. The number of new PET studies using C-11-PIB PET was 695. I-131-radioiodine targeted therapies showed an increase, including 3,644 patients (53.6 %) for thyroid cancer and 4,889 patients (17.9 %) for hyperthyroidism. Out-patient thyroid bed ablation therapy with 30 mCi of I-131 accounted for 21.0 % of cancer patients. The number of admission rooms decreased from 158 to 135 in 5 years. In vitro radioassays have been declining continuously since 1992, with the number of studies of 9.0 million in 2012. Single-photon examinations showed a continuous tendency toward a decline in the survey. In contrast, the number of hybrid SPECT/CT scanner examinations has increased. PET/CT study in the oncology field and radionuclide targeted therapy have steadily increased.

膵・胆管合流異常の診断基準は、2013年9月に改訂された。その診断基準に、画像診断として、EUSまたはmultidetector-row CT(MD-CT)のmulti-planar reconstruction (MPR)像などで、膵管と胆管が十二指腸壁外で合流することを確認する項目が新設された。MD-CTは、造影剤アレルギーがある場合、腎機能が不良の場合は施行できない欠点はあるが、EUSのごとく術者の技量に左右されないことや同時に癌の精査が行える利点がある。自験例27例の検討では、MD-CTにて全例で膵・胆管合流異常の診断が可能であった。既報告では、その診断率は小児例では19.6%、成人例では58.3〜100.0%であり、成人例では診断率は満足できる報告もある。MD-CTにて膵・胆管合流異常の診断は可能であるが、日本膵・胆管合流異常研究会による合流形式分類のc型のように、複雑な合流形式をとるものには、術式の立案のためERCPを追加で行う必要がある。(著者抄録)

Strontium-89 chloride (Sr-89) bremsstrahlung single photon emission computed tomography (SPECT) imaging was evaluated for detecting more detailed whole body Sr-89 distribution. Sr-89 bremsstrahlung whole body planar and merged SPECT images were acquired using two-detector SPECT system. Energy window A (100 keV +/- A 50 %) for planar imaging and energy window A plus adjacent energy window B (300 keV +/- A 50 %) for SPECT imaging were set on the continuous spectrum. Thirteen patients with multiple bone metastases were evaluated. Bone metastases can be detected with Tc-99m-HMDP whole body planar and merged SPECT images and compared with Sr-89 bremsstrahlung whole body planar and merged SPECT images. Based on the location of metastatic lesions seen as hot spots on Tc-99m-HMDP images as a reference, the hot spots on Sr-89 bremsstrahlung images were divided into the same bone parts as Tc-99m-HMDP images (a total of 35 parts in the whole body), and the number of hot spots were counted. We also evaluated the incidence of extra-osseous uptakes in the intestine on Sr-89 bremsstrahlung whole body planar images. A total of 195 bone metastatic lesions were detected in both Tc-99m-HMDP whole body planar and merged SPECT images. Detection of hot spot lesions in Sr-89 merged SPECT images (127 of 195; 66 %) was more frequent than in Sr-89 whole body planar images (108 of 195; 56 %), based on metastatic bone lesions in Tc-99m-HMDP whole body planar and merged SPECT images. A large intestinal Sr-89 accumulation was detected in 5 of the 13 patients (38 %). Sr-89 bremsstrahlung-merged SPECT imaging could be more useful for detailed detection of whole body Sr-89 distribution than planar imaging. Intestinal Sr-89 accumulation due to Sr-89 physiologic excretion was detected in feces for 4 days after tracer injection.

We modified the Imaging Performance Assessment of CT scanners (ImPACT) to evaluate the organ doses and the effective dose based on the International Commission on Radiological Protection (ICRP) Publication 110 reference male/female phantom with the Aquilion ONE ViSION Edition scanner. To select the new CT scanner, the measurement results of the CTDI100, c and CTDI100, p for the 160 (head) and the 320 (body) mm polymethylmethacrylate phantoms, respectively, were entered on the Excel worksheet. To compute the organ doses and effective dose of the ICRP reference male/female phantom, the conversion factors obtained by comparison between the organ doses of different types of phantom were applied. The organ doses and the effective dose were almost identical for the ICRP reference male/female and modified ImPACT. The results of this study showed that, with the dose assessment of the ImPACT, the difference in sex influences only testes and ovaries. Because the MIRD-5 phantom represents a partially hermaphrodite adult, the phantom has the dimensions of the male reference man including testes, ovaries, and uterus but no female breasts, whereas the ICRP male/female phantom includes whole-body male and female anatomies based on high-resolution anatomical datasets. The conversion factors can be used to estimate the doses of a male and a female accurately, and efficient dose assessment can be performed with the modified ImPACT.

When performing endovascular aortic repair (EVAR) procedures, clinicians sometimes encounter cases in which the indications for EVAR are beyond the instruction for use (IFU). In EVAR, proximal neck fixation is the most important factor. This report describes several techniques and tips for EVAR in cases presenting with a difficult short neck or angled neck, especially when using the Gore Excluder®. Endo-wedge techniques (EWT), including non-sheath-assisted EWT with sheath-assisted strategies, are presented. We describe the scrum technique, which is a special procedure that is only feasible when using the Gore Excluder®. In this technique, intentional wire bending around the proximal neck portion occurs by pushing from both sides of the guidewire. This technique is applicable in cases with a sharply angled neck. The scrum with EWT is a more precise strategy for cases with a short or angled neck. Other troublesome cases include limb occlusion caused by weak points in the Gore Excluder® body and legs. The very rare complication of stent-graft collapse is also reviewed. © Banno et al.

This study aimed to develop a new system, named CD-Well, for mouse PET dynamic study. CD-Well allows the determination of time-activity curves (TACs) for arterial whole blood and plasma using 2-3 mu L of blood per sample; the minute sample size is ideal for studies in small animals. The system has the following merits: (1) measures volume and radioactivity of whole blood and plasma separately; (2) allows measurements at 10 s intervals to capture initial rapid changes in the TAC; and (3) is compact and easy to handle, minimizes blood loss from sampling, and delay and dispersion of the TAC. CD-Well has 36 U-shaped channels. A drop of blood is sampled into the opening of the channel and stored there. After serial sampling is completed, CD-Well is centrifuged and scanned using a flatbed scanner to define the regions of plasma and blood cells. The length measured is converted to volume because the channels have a precise and uniform cross section. Then, CD-Well is exposed to an imaging plate to measure radioactivity. Finally, radioactivity concentrations are computed. We evaluated the performance of CD-Well in in vitro measurement and in vivo F-18-fluorodeoxyglucose and [C-11] 2-carbomethoxy-3 beta-(4-fluorophenyl) tropane studies. In in vitro evaluation, per cent differences (mean +/- SE) from manual measurement were 4.4 +/- 3.6% for whole blood and 4.0 +/- 3.5% for plasma across the typical range of radioactivity measured in mouse dynamic study. In in vivo studies, reasonable TACs were obtained. The peaks were captured well, and the time courses coincided well with the TAC derived from PET imaging of the heart chamber. The total blood loss was less than 200 mu L, which had no physiological effect on the mice. CD-Well demonstrates satisfactory performance, and is useful for mouse PET dynamic study.

1982年から5年ごとに各時代の核医学診療の実態を把握するため、「全国核医学診療実態調査」を実施してきたが、2012年6月に第7回調査を過去6回の調査と同様の方法で実施し、過去の調査結果と比較し報告した。核医学診療を行っている1274施設全てに調査票を送付した。回答があったのは1167施設で回答回収率は91.6%と前回同様90%を超える高い数値であった。全核医学施設は全体として調査開始から横ばいかやや増加の傾向にあるが、インビボ検査の施設は5年前に比べ減少した。検査件数は前回より減少傾向にあったが今回更に27万件/年(19%)減少した。一方、PET検査に関しては前回ほどの伸びはなかったが施設内で4割、検査数では16万件増加した。非密封RI治療に関しても新規薬剤を含め全体で6割、治療件数で4000件増加した。インビトロ検査に関しては減少が続き、実施施設数は1/3になったが、検査件数の減少は3割に留まった。CTやMRIなどの診断技術の進歩により、検査の枠組みが変化すると共に核医学の中でもインビボ検査からPET検査、核医学診断からRI内用療法への重心のシフトが明らかになった。

We report here a case of rupture of a substitute urinary bladder due to a relapse of bladder cancer detected incidentally on a bone scan. The radionuclides used in bone scans accumulate in the bone and are excreted in the urine. Incidental detection of rupture of a substitute urinary bladder may lead to appropriate intermediate neobladder repair.

Background: Radiation pneumonitis (RP) and organizing pneumonia (OP) are the two main types of lung damage that can occur after lung irradiation. The goal of this study was to evaluate the relationship between RP and OP after irradiation for breast cancer. Methods: Four hundred and twenty-eight patients who underwent radiotherapy for breast cancer were identified. The whole breast was irradiated with two tangential photon beams. Chest computed tomography (CT) scan were performed when patients showed any symptoms that were suspicious for pneumonitis. Results: Five patients (1.2%) were diagnosed with OP. All five patients showed ground glass opacities and consolidation of the border of the lesion of RP in the radiation fields. Infiltration of OP spread from the site of RP to the hilum of the ipsilateral lung. Between RP and OP, a free region space (FRS) could be detected. Conclusions: OP is closely related to RP. All OP lesions developed near the site of RP.