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Dive into the research topics where Naoya Yama is active.

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Featured researches published by Naoya Yama.


CardioVascular and Interventional Radiology | 2001

The Spectrum of Findings in Supra-Aortic Takayasu’s Arteritis as Seen on Spiral CT Angiography and Digital Subtraction Angiography

Satoru Yoshida; Hedenari Akiba; Mitsuharu Tamakawa; Naoya Yama; Miki Takeda; Masato Hareyama; Tomoaki Nakata; Kazuaki Shimamoto

Takayasu’s arteritis (TA) mainly affects the aorta and its major branches. The lesions are distributed in all elastic arteries that possess vasa vasorum. The frequency of the sites of arterial involvement reflects racial and geographic differences [1–7]. In Japan, stenosis or occlusion of the supra-aortic arch branches is commonly observed and leads to pulseless disease [5–7]. We present the spiral CT angiography (CTA) and intraarterial digital subtraction angiography (IA-DSA) findings of the aortic arch in TA. The spectrum of findings on CTA are stenosis, occlusion, dilatation, arterial wall thickening, and calcification of the aortic arch branches.


Infection | 2003

Emergency Endovascular Stent-Grafting for Infected Pseudoaneurysm of Brachial Artery

Yoshihiko Kurimoto; Yoshihiko Tsuchida; Jota Saito; Naoya Yama; Eichi Narimatsu; Yasufumi Asai

Abstract.The use of covered stents in an infected field is controversial. It is generally recommended that infected aneurysms be treated using autografts or allografts. We report a case of infected brachial pseudoaneurysms that developed after medical debridement of a methicillinresistant Staphylococcus aureus (MRSA)-infected wound of the right arm and emergency brachial artery bypass-grafting using the saphenous vein, which was successfully treated by endovascular stent-grafting followed by antibiotic administration. The present case suggests that endovascular stent-grafting prevents rupture and occlusion of infected aneurysms and enables the continued administration of antibiotics.


Digestive Surgery | 2003

Efficacy of SPIO-MR imaging in the diagnosis of liver metastases from colorectal carcinomas.

Tomohisa Furuhata; Kenji Okita; Tetsuhiro Tsuruma; Fumitake Hata; Yasutoshi Kimura; Tadashi Katsuramaki; Mitsuhiro Mukaiya; Naoki Hirokawa; Takeshi Ichimura; Naoya Yama; Kazumitsu Koito; Kazuaki Sasaki; Koichi Hirata

Aim: To determine whether superparamagnetic iron oxide-enhanced magnetic resonance imaging (SPIO-MRI) could replace intravenous contrast-enhanced spiral CT (iv-CT) and spiral CT during arterial portography (CTAP) combined with spiral CT hepatic angiography (CTHA) in the diagnosis of liver metastases from colorectal carcinomas. Methods: Twenty-six adult patients with liver metastases were studied preoperatively by means of iv-CT, CTAP/CTHA, and SPIO-MRI. Preoperative diagnoses using iv-CT, CTAP/CTHA, and SPIO-MRI were compared with intraoperative and pathological findings in resected specimens. The gold standard for the lesions that were resected was histological examination. Intraoperative findings represented the gold standard for lesions that were not resected. Results: Twenty-six patients were found to have a total number of 43 liver metastases. The sensitivities of iv-CT, CTAP/CTHA, and SPIO-MRI were 74.4, 100, and 90.7%, respectively. SPIO-MRI was significantly superior to iv-CT (p < 0.05). The positive predictive values of iv-CT, CTAP/CTHA, and SPIO-MRI were 97.0, 91.5, and 100%, respectively. CTAP/CTHA yielded four false-positive lesions. In contrast, we detected no false-positive findings using SPIO-MRI. Conclusions: These results suggest that SPIO-MRI might not completely replace CTAP/CTHA, but could replace iv-CT in the diagnosis of liver metastases from colorectal carcinomas. It is thought that SPIO-MRI is a promising imaging modality for diagnosing liver metastases in patients with colorectal carcinoma because of its relatively high sensitivity and extremely high specificity.


Journal of Magnetic Resonance Imaging | 2007

Double-subtraction maximum intensity projection MR angiography for detecting the artery of Adamkiewicz and differentiating it from the drainage vein

Hideki Hyodoh; Ryuji Shirase; Hidenari Akiba; Mitsuharu Tamakawa; Kazusa Hyodoh; Naoya Yama; Takaharu Shonai; Masato Hareyama

To evaluate the efficacy of double‐subtraction magnetic resonance angiography (MRA) (subtraction of the subtracted venous phase image from the subtracted arterial dominant phase image) for depicting the artery of Adamkiewicz and differentiating it from the drainage vein.


European Journal of Radiology | 2001

Pancreas: imaging diagnosis with color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography

Kazumitsu Koito; Tsutomu Namieno; Tatsuya Nagakawa; Naoki Hirokawa; Takeshi Ichimura; Takaharu Syonai; Naoya Yama; Masanori Someya; Kensei Nakata; Koich Sakata; Masato Hareyama

Recent advances of ultrasound imaging have made possible to depict various diseases and conditions of the pancreas. Color/power Doppler ultrasonography, endoscopic ultrasonography, and intraductal ultrasonography are feasible to show vascular abnormalities, differentiate the solid and cystic tumors, decide tumor extent, and help to perform interventional treatments of the pancreatic diseases. Those techniques will contribute to the more precise and easier diagnosis and to prompt decision of the treatments of the pancreatic disorders. Radiologists should recognize the diagnostic feasibility and limitations of those techniques in order to avoid unnecessary examinations on the patients, and obtain precise diagnostic images.


Surgery Today | 2007

Out-of-Hospital Cardiopulmonary Arrest Due to Penetrating Cardiac Injury Treated by Percutaneous Cardiopulmonary Support in the Emergency Room: Report of a Case

Yoshihiko Kurimoto; Hitoshi Kano; Naoya Yama; Satoshi Nara; Mamoru Hase; Yasufumi Asai

Penetrating cardiac injury tends to generally be repaired without cardiopulmonary bypass in the operating room. We herein report the case of penetrating cardiac injury repaired using percutaneous cardiopulmonary support in an emergency room. A 57-year-old man attempted suicide by stabbing himself in the left anterior chest with a knife. Although the patient suffered cardiopulmonary arrest for 7 min in the ambulance, spontaneous circulation was restored following pericardiotomy through emergency left thoracotomy in the emergency room. To prevent coronary artery injury and control the massive bleeding, percutaneous cardiopulmonary support was instituted without systemic heparinization and the cardiac injury was repaired in the emergency room. The patient was then transferred to another hospital on day 46 for further rehabilitation. Percutaneous cardiopulmonary support might be helpful for treating critical patients in an emergency room, even in the case of trauma patients.


Acute medicine and surgery | 2018

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J‐SSCG 2016)

Osamu Nishida; Hiroshi Ogura; Moritoki Egi; Seitaro Fujishima; Yoshiro Hayashi; Toshiaki Iba; Hitoshi Imaizumi; Shigeaki Inoue; Yasuyuki Kakihana; Joji Kotani; Shigeki Kushimoto; Yoshiki Masuda; Naoyuki Matsuda; Asako Matsushima; Taka-aki Nakada; Satoshi Nakagawa; Shin Nunomiya; Tomohito Sadahiro; Nobuaki Shime; Tomoaki Yatabe; Yoshitaka Hara; Kei Hayashida; Yutaka Kondo; Yuka Sumi; Hideto Yasuda; Kazuyoshi Aoyama; Takeo Azuhata; Kent Doi; Matsuyuki Doi; Naoyuki Fujimura

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J‐SSCG 2016), a Japanese‐specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 in Japanese. An English‐language version of these guidelines was created based on the contents of the original Japanese‐language version.


CardioVascular and Interventional Radiology | 1998

Pseudoaneurysm of the Superficial Femoral Artery in Behçet's Disease with Spontaneous Thrombosis Followed by CT Angiography

Satoru Yoshida; Hidenari Akiba; Mituharu Tamakawa; Miki Takeda; Naoya Yama; Masato Hareyama; Kazuo Morita; Atsushi Masuda; Kazuaki Shimamoto

Abstract A 25-year-old man developed sudden pain and a pulsating mass in the left thigh. A diagnosis of Behçets disease was made because of four major symptoms. Laboratory data indicated active inflammation. Emergency spiral computed tomographic angiography (CTA) showed an aneurysm of the left superficial femoral artery (SFA). Under steroid therapy, follow-up spiral CTA showed spontaneous occlusion of the aneurysm. In the active phase of arteritis, spiral CTA is useful for the diagnosis of arterial lesions to avoid the arterial puncture of conventional arteriography.


Clinical Pediatric Endocrinology | 2015

An adolescent case of familial hyperparathyroidism with a germline frameshift mutation of the CDC73 gene

Takako Takeuchi; Yuko Yoto; Takeshi Tsugawa; Hotaka Kamasaki; Atsushi Kondo; Jiro Ogino; Tadashi Hasegawa; Naoya Yama; Sawa Anan; Shinya Uchino; Aki Ishikawa; Akihiro Sakurai; Hiroyuki Tsutsumi

Abstract. A 13-yr-old boy who complained of persistent nausea, vomiting and weight loss had hypercalcemia and an elevated intact PTH level. Computed tomography confirmed two tumors in the thyroid gland. The tumors were surgically removed and pathologically confirmed as parathyroid adenoma. Because his maternal aunt and grandmother both had histories of parathyroid tumors, genetic investigation was undertaken for him, and a germline frameshift mutation of the CDC73 gene was identified. CDC73 gene analysis should be done on individuals who are at risk of familial hyperparathyroidism, including those who are asymptomatic, and they should be followed for potential primary hyperparathyroidism and associated disorders including resultant parathyroid carcinoma.


Abdominal Imaging | 2006

Nominal free air in the left inguinal fossa due to perforation of the sigmoid colon in a case of blunt abdominal trauma: CT diagnosis

Naoya Yama; Yasutoshi Kimura; Hiroomi Tatsumi; C. Kihara; Yoshihiko Kurimoto; E. Narimatsu; Hideki Ura; Kazumitu Koito; Yasufumi Asai; Koichi Hirata; M. Hreyama

We present a case of perforation of the sigmoid colon due to blunt abdominal trauma. Computed tomography showed nominal free air in the inguinal fossa. The distribution of free air may be a clue to the site of an injured intestine. Early detection of intestinal injury is difficult, but repeated computed tomography after several hours may reveal increased free air.

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Masato Hareyama

Sapporo Medical University

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Yasufumi Asai

Sapporo Medical University

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Kazumitsu Koito

Sapporo Medical University

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Eichi Narimatsu

Sapporo Medical University

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Hidenari Akiba

Sapporo Medical University

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Satoshi Nara

Sapporo Medical University

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Hideki Hyodoh

Sapporo Medical University

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