著者

朱 佐木 木曽原 昌也 深谷 有 三宅 庸介 河合 辰哉 樋渡 昭雄

出版者

一般社団法人 日本放射線科専門医会・医会

雑誌

日本放射線科専門医会・医会学術雑誌 (ISSN:27586499)

巻号頁・発行日

vol.3, pp.90-93, 2023 (Released:2023-12-06)

参考文献数

5

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In recent years, there has been an increase in reported cases of acute coronary syndrome, as-sociated with allergic reactions, namely Kounis syndrome. In this report, we present a case of suspected Kounis syndrome that occurred after the administration of contrast media.A female patient in her 60s with a medical history of paroxysmal atrial fibrillation, lower limb arteriosclerosis obliterans, and end-stage renal failure underwent contrast-enhanced CT using iodinated contrast media for the evaluation of lower limb arteriosclerosis obliterans. Imme-diately after administration of the contrast media, she experienced itchiness and rash on the right lower-back, followed by difficulty breathing and intense neck pain. Subsequently, she experienced cardiopulmonary arrest and was treated with cardiopulmonary resuscitation. Electrocardiogram revealed ST elevation in the II, III, and aVF leads. Subsequent coronary angiography revealed complete occlusion of the right coronary artery. The patient underwent successful percutaneous coronary intervention. The day after treatment, contrast-enhanced CT showed extravasations at the bilateral internal mammary arteries which were treated with transcatheter arterial embolization. The patient's condition improved, and she was discharged.Kounis syndrome is classified into three types. Type I is caused by coronary artery spasm, type II is caused by rupture of a coronary artery plaque and subsequent thrombus formation, and type III is caused by stent thrombosis. Our case was likely diagnosed as type II based on her cardiovascular risk factors and complete occlusion of the right coronary artery. It appears to be important to recognize the symptoms and physical findings suggestive of acute coronary syndrome during the management of anaphylactic reactions and to consider Kounis syndrome as a potential diagnosis.

著者

深谷 有喜

出版者

一般社団法人 日本真空学会

雑誌

Journal of the Vacuum Society of Japan (ISSN:18822398)

巻号頁・発行日

vol.59, no.2, pp.35-39, 2016 (Released:2016-03-18)

参考文献数

25

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Total-reflection high-energy positron diffraction (TRHEPD) is a surface-sensitive tool owing to the total reflection of positrons. Since the sign of the crystal potential energy for positrons is positive, opposite to that for electrons, the positron beam at a grazing incidence is totally reflected at a crystal surface. The penetration depth of the positron beam in the total reflection region is estimated to be about a few Å, which corresponds to the thickness of 1-2 atomic layers. Thus, the positron beam in the total reflection region sees only the topmost surface layer of the crystal. Slightly over the critical angle for the total reflection, the positon beam also sees the underlying surface layer. Adjusting the glancing angle of the incident positron beam, the diffraction intensity selectively contains information about the topmost and the underlying surface layers without any effect from the bulk. Therefore, the TRHEPD is very useful for structure determinations of crystal surface and two-dimensional atomic sheet adsorbed on the substrate. In this paper, we will show the surface-sensitivity of the TRHEPD. Shown is also the recent result of silicene, two-dimensional atomic sheet of silicon, using the TRHEPD.