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Featured researches published by Keiji Ataka.


Angiology | 2000

Intravenous Leiomyomatosis Extending into the Right Ventricular Cavity: One-Stage Radical Operation Using Cardiopulmonary Bypass: A Case Report

Hidetaka Wakiyama; Takaki Sugimoto; Keiji Ataka; Chojiro Yamashita; Yoshihiko Tsuji; Keitaro Nakagiri; Kyozo Inoue; Masayoshi Okada

The authors describe a 47-year-old woman with intravenous leiomyomatosis (IVL) extending into the right ventricular cavity. This rare entity is a neoplasm originating from smooth muscle of the uterus, with vermiform extensions into the inferior vena cava. The patient underwent a one-stage operation under simultaneous sternotomy and laparo tomy, and radical excision of the tumor was successfully achieved with use of normoth ermic cardiopulmonary bypass. Although this tumor is histologically benign, it sometimes extends into the cardiac cavity and causes sudden death due to incarceration into the atri oventricular orifice. Moreover, recurrence or lung metastasis of IVL has been reported. The authors recommend a one stage-radical resection of the tumor or a two-staged operation within a short interval. In the literature, 24 surgical cases of the intravenous leiomyomatosis with intracardiac extension have been reported. The diagnosis and surgical treatment of this tumor are reviewed and discussed.


Journal of Vascular Surgery | 1998

Surgical treatment for transvenous tumor extension into the heart: Four cases

Yoshihiko Tsuji; Chojiro Yamashita; Hidetaka Wakiyama; Yoshiya Toyoda; Masato Yoshida; Takaki Sugimoto; Keiji Ataka; Noboru Ishii; Tsutomu Shida; Masayoshi Okada

From 1984 to 1996, four patients with transvenous intracardiac tumor extension underwent operations in the Kobe University Hospital. The primary tumors of two were intravenous leiomyomatoses originating from the uterus; a third patient had invasive thymoma, and the fourth patient had clear cell sarcoma of the kidney. In 1985, one patient had a curative, staged resection. One-stage operations were carried out in three patients, and all intracardiac tumors were successfully resected en bloc with the primary tumors under conditions of electrical ventricular fibrillation and mild hypothermia. Combined venous reconstructions were necessary for en bloc resection in three cases. Two patients with malignancy received postoperative chemoradiotherapy, and all four patients were discharged uneventfully from our hospital. We consider radical resection with curative intent only for patients with tumors extending into the heart. In these cases, a one-stage operation is preferable, and electrical ventricular fibrillation with mild hypothermia is a recommended method of circulatory assist because of its simplicity.


Surgery Today | 2001

Hepatocellular Carcinoma with a Sarcomatous Appearance : Report of a Case

Yoshihiko Tsuji; Kenji Okada; Masato Fukuoka; Yoshihisa Watanabe; Keiji Ataka; Rieko Minami; Keisuke Hanioka; Shiro Tachibana; Hiroshi Saito; Akinori Sasada; Yutaka Okita

Abstract A 59-year-old man was admitted with general fatigue, an epigastric mass, and remittent fever. Radiological examinations disclosed a huge solid-to-cystic mass in the right lobe of the liver, and the mass severely compressed the right diaphragm, the inferior vena cava, and the right atrium. In addition, the patient suffered from chronic hepatitis; however, the serum α-fetoprotein, carcinoembryonic antigen, and PIVKA II levels were all within the normal ranges. The serum C-reactive protein level was 7.71 mg/dl. With a clinical diagnosis of a malignant hepatic tumor invading the right diaphragm, surgery was performed. The tumor originated from segments IV and VII of the liver, was well defined, and grew extrahepatically. The tumor was resected using an ultrasonic cavitational aspirator together with the infiltrated right diaphragm. The resected tumor measured 23 × 13 × 23 cm in size and weighed 3 700 g. Histologically, the tumor was found to consist of hepatocellular carcinomatous component and sarcomatous component. In the sarcomatous component, spindle-shaped cells which were positive for the immunohistochemical localization of vimentin, α-smooth muscle actin, and keratin were identified. The postoperative course was uneventful. The value of the serum C-reactive protein returned to within the normal range, and the patient became afebrile. The patient received a postoperative combination chemotherapy (etoposide, epirubicin, and cisplatin), and remains well with no signs of recurrence 12 months after the operation.


Hpb Surgery | 1998

Complete Caudate Lobectomy:Its Definition, Indications, and Surgical Approaches

Akinori Sasada; Keiji Ataka; Kazuhiko Tsuchiya; Hiroyuki Yamagishi; Hiromi Maeda; Masayoshi Okada

There are three ways to approach and resect the caudate lobe of the liver, that is; and isolated caudate lobectomy, a combined resection of the liver overlying the caudate lobe, and a transhepatic anterior approach by splitting parenchyma of the liver. We had two patients with neoplasms originating in the caudate lobe who underwent a complete caudate lobectomy. Both patients have been doing well without liver dysfunction. Although after the transhepatic anterior approach we anticipated an adverse effect from splitting the parenchyma of the liver, the postoperative course was uneventful and similar to that of the right side approach.


Vascular Surgery | 1997

Retrograde Cerebral Perfusion for Aortic Arch Operation

Naoki Yoshimura; Masayoshi Okada; Toshiaki Ota; Takashi Azami; Hideaki Nohara; Keiji Ataka; Chojiro Yamashita

Deep hypothermic retrograde cerebral perfusion (RCP) has recently been the focus of interest as a simple new technique of brain protection during the operation for thoracic aneurysms. During the period from January 1991 to July 1994, 21 consecutive patients underwent operations on the various portions of the thoracic aorta with the use of deep hypothermic RCP. There were 10 men and 11 women, ages ranging from twenty-eight to seventy-eight (mean 61.4) years old. There were 9 cases with true aortic aneurysm, and 12 with dissecting aneurysm. In 8 patients (38.1%) the procedures were done on an emergency basis for ruptured/impending ruptured aneurysms or acute dissecting aneurysms. Four patients died before the adequate assessment of their neurologic function. One patient had a cerebral infarction probably due to dissection of the left common carotid artery. The remaining 16 patients showed clear consciousness and had no serious neuro logic complications postoperatively. Total perfusion time averaged 297 ± 110 minutes (ranging from 162 to 548 minutes). Rectal temperatures were 20.1 ± 1.4°C (ranging from 18.0 to 22.5°C). RCP time averaged 51.3 ± 13.9 minutes (ranging from twenty-seven to eighty minutes). Blood gas analysis of the returned blood sampled from the left common carotid artery or the innominate artery and the ophthalmoscopic findings demonstrated the insufficiency of blood and oxygen supply to the brain during RCP. Therefore, RCP time should be shortened and pharmacologic cerebral protection is recommended to reduce neurologic complications during operations on the thoracic aorta using RCP.


Chest | 1996

Profile of Chest Injuries Arising From the 1995 Southern Hyogo Prefecture Earthquake

Naoki Yoshimura; Shinichi Nakayama; Keitaro Nakagiri; Takashi Azami; Keiji Ataka; Noboru Ishii


Annals of Thoracic and Cardiovascular Surgery | 1999

Surgical Assessment of Tricuspid Valve Replacement for Severe Tricuspid Regurgitation without Stenosis

Takaki Sugimoto; Masayoshi Okada; Chojiro Yamashita; Keiji Ataka; Masato Yoshida; Yoshiya Toyoda; Nobuchika Ozaki


The Kobe journal of the medical sciences | 1998

Results of surgical treatment for thoracoabdominal aneurysm using cardiopulmonary bypass under moderate hypothermia and selective visceral artery perfusion.

Chojiro Yamashita; Keiji Ataka; Yoshida M; Takaki Sugimoto; Hidetaka Wakiyama; Masayoshi Okada


Annals of Thoracic and Cardiovascular Surgery | 1999

The Effect of Direct Lidocaine Injection into the Clamped Aortic Segment on the Spinal Evoked Potential : Early Diagnosis for Spinal Cord Ischemia

Hideaki Nohara; Masayoshi Okada; Chojiro Yamashita; Keiji Ataka; Naoki Yoshimura


Annals of Thoracic and Cardiovascular Surgery | 1998

Surgical Results of Composite Graft Replacement of the Aortic Root Aneurysm

Chojiro Yamashita; Keiji Ataka; Masato Yoshida; Yoshihiko Tsuji; Teruo Yamashita; Keitarou Nakagiri; Hidetaka Wakiyama; Kyouzo Inoue; Masayoshi Okada

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