Tamura, Masashi



School of Medicine, Department of Radiology (Diagnostic Radiology) (Shinanomachi)




Papers 【 Display / hide

  • Predictors of Occlusion of Hepatic Blood Vessels after Irreversible Electroporation of Liver Tumors

    Tamura M., Pedersoli F., Schulze-Hagen M., Zimmerman M., Isfort P., Kuhl C.K., Schmitz-Rode T., Bruners P.

    Journal of Vascular and Interventional Radiology (Journal of Vascular and Interventional Radiology)  31 ( 12 ) 2033 - 2042.e1 2020.12

    ISSN  10510443

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    © 2020 SIR Purpose: To examine predictors of midterm occlusion in portal and hepatic veins within or adjacent to the ablation zone after irreversible electroporation (IRE) of liver tumors. Materials and Methods: This retrospective cohort analysis included 39 patients who underwent CT-guided IRE of liver tumors. Vessels within or adjacent to the ablation zone were identified on CT images acquired immediately after the procedure, and the positional relationships with the ablation zone (within/adjacent), locations (proximal/distal), and diameters (< 4 mm or ≥ 4 mm) were evaluated. Using contrast-enhanced follow-up scans, each vessel was classified as patent, stenosed, or occluded. Associations between vessel occlusion and each variable were investigated. Results: Overall, 33 portal veins and 64 hepatic veins were analyzed. Follow-up scans showed occlusion in 12/33 (36.7%) portal veins and 17/64 (26.6%) hepatic veins. Vessels within the ablation zone were occluded significantly more frequently than vessels adjacent to the ablation zone (portal: 55.6% [10/18] vs 13.3% [2/15], P = .04; hepatic: 45.4% [15/33] vs 6.4% [2/31], P = .011). Vessels with a diameter < 4 mm were also occluded significantly more frequently than vessels with a diameter ≥ 4 mm (portal: 72.7% [8/11] vs 18.1% [4/22], P = .011; hepatic: 54.8% [17/31] vs 0% [0/33], P < .001). The respective positive and negative predictive values for occlusion of vessels categorized as both within and < 4 mm were 88% (7/8) and 82% (20/25) for portal veins and 79% (15/19) and 96% (43/45) for hepatic veins. Conclusions: Midterm vessel occlusion after liver IRE could be predicted with relatively high accuracy by assessing ablation location and vessel diameter.

  • Arteriovenous malformation on the sole of the foot treated successfully by embolization

    Yuzaki I., Aramaki-Hattori N., Tamura M., Torikai H., Okabe K., Sakai S., Nakatsuka S., Jinzaki M., Kishi K., Inoue M.

    Radiology Case Reports (Radiology Case Reports)  15 ( 12 ) 2621 - 2626 2020.12

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    © 2020 Arteriovenous malformations of the sole of the foot are rare and can cause disturbances in normal living activities. We report a case of a plantar arteriovenous malformation in a 24-year-old male with pain and difficulty in walking. The arteriovenous malformation was complex, with a large and poorly marginated nidus, so we considered that with surgical resection, walking disabilities would be inevitable. When surgical removal of vascular mass is difficult, embolization alone can be effective. Therefore, he was treated with 4 therapeutic embolization procedures. Transvenous approaches to the venous sac and direct punctures of the nidus was performed. The nidus was successfully eradicated by embolization using alcohol, resulting in the disappearance of associated symptoms. Appropriate imaging is essential for diagnosis and evaluation of treatment. We were successful in achieving improved quality of life and satisfaction for a rare and difficult case by percutaneous embolization and sclerotherapy.

  • Successful depiction of systemic collateral supply to pulmonary artery in CTEPH using time-resolved 4D CT angiography: a case report

    Tamura M., Kawakami T., Yamada Y., Kataoka M., Nakatsuka S., Fukuda K., Jinzaki M.

    Pulmonary Circulation (Pulmonary Circulation)  10 ( 2 )  2020

    ISSN  20458932

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    © The Author(s) 2020. A 49-year-old man with CTEPH (pre-procedural mean pulmonary artery pressure: 36 mmHg) underwent balloon pulmonary angioplasty. Chronic total occlusion of the left inferior pulmonary artery trunk was observed. To evaluate the collateral vessels of the chronic total occlusion, 4D-CTA was performed. The examination was performed using a 256-row detector CT system using the test bolus tracking method. 4D-CTA showed the bronchial artery-to-left inferior pulmonary artery collateral supply, which was confirmed by a selective bronchial artery angiography. The patient’s symptoms improved with balloon pulmonary angioplasty of the other stenotic lesions. 4D-CTA can noninvasively evaluate the anatomy and hemodynamics of multiple systemic collaterals simultaneously. This technique can support interventions in systemic artery-to-pulmonary artery collaterals, such as embolization, and could be helpful in challenging balloon pulmonary angioplasty interventions for chronic total occlusion to identify vessel structures distal to the chronic total occlusion and collateral channels for a retrograde approach.

  • Imaging Findings of Atypical Type II Endoleak Through Vasa Vasorum After Abdominal Endovascular Aneurysm Repair

    Torikai H., Inoue M., Nakatsuka S., Tamura M., Yashiro H., Yoshitake A., Shimizu H., Jinzaki M.

    CardioVascular and Interventional Radiology (CardioVascular and Interventional Radiology)  41 ( 1 ) 186 - 190 2018.01

    ISSN  01741551

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    © 2017, Springer Science+Business Media, LLC and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE). A type II endoleak (T2EL) is the most common endoleak after endovascular aneurysm repair (EVAR), and a persistent T2EL has been occasionally associated with aneurysmal enlargement. Typical findings of a T2EL consist of an endoleak cavity with inflow and outflow arteries of aortic branch vessels. However, an atypical T2EL, in which hypertrophied vasa vasorum and enlargement of a thrombosed aneurysm are observed, has no endoleak cavity. We have seen three cases of continuous aortic aneurysmal growth after EVAR caused by atypical T2ELs without endoleak cavities through developed vasa vasorum. In this report, the imaging findings of selective angiography and dynamic computed tomography of these cases are reviewed.

Research Projects of Competitive Funds, etc. 【 Display / hide

  • 免疫不全豚を用いた肝癌新規実験モデルにおける血流動態/画像-病理相関の妥当性検討


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 田村 全, Grant-in-Aid for Young Scientists (B), Principal Investigator


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