Environmental Radiation Exposure Surveys of the Leksell Gamma Unit, Veterans General Hospital-Taipei

台北榮民總醫院加馬機環境輻射偵測

趙敏(Max M. Chao) ； 李玉麟(Yuh L. Lee) ； 趙良曉(Liung S. Chao) ； 顏上惠(Sang H. Yen) ； 鍾文裕(Wen Y. Chung) ； 潘宏基(David H. C. Pan) ； 陳光耀(Kuang Y. Chen)

《中華放射線醫學雜誌》 21卷5期 (1996/10) Pp. 265-269

摘要

立體定位放射手術在近幾年來，對治療動靜脈畸形及腦內深部腫瘤，扮演著非常重要的角色。經由－固定在病人頭部之立體定位頭架，加馬機可以經由一次給予的輻射劑量，集中照射在腫瘤處而減少周圍腦組織的傷害。台北榮總加馬機於1992年9月裝置，六個月後開始治療病人。加馬機射源為鈷六十，總活性約6040居里。雖然加馬機本身有防護，然而背景輻射和輻射滲漏是不可避免的。所以在治療室內及週圍環境的輻射測量是非常重要。輻射曝露的測量包含在有病人和沒有病人時二種情況。在治療室內的曝露量約在10-90000微西弗每小時，而週圍環境約偽0.2-0.8微西弗每小時。偵測結果顯示，在治療室內及四週圍環境的輻射曝露量均符合原子能委員會之規範。

關鍵字

劑量測定 ； 治療性放射線學

並列摘要

A stereotactic radiosurgery unit has been playing a significant role in the treatment of arteriovenous malformations (AVM), and other intracranial lesions such as pituitary adenomas, meningiomas and metastases over the past several years. It is a technique in which the region to be treated can receive a maximum dose, while the surrounding normal tissue receives only a limited dose. This is possible as the Gamma Unit delivers a single high dose of external radiation to the target with the help of a stereotactic frame attached to the patient's head. The Gamma Unit at the Veterans General Hospital-Taipei was installed in September 1992, starting treatment use six months later. The source of this Leksell Gamma Unit is Co-60, with a total activity of 6040 Ci. Although the Gamma Unit is shielded, background radiation and radiation leakage are unavoidable. Therefore, it is essential to measure the exposure rates in both the treatment room and the surrounding areas. The radiation exposures were measured with and without the patient and humanoid phantom's presence. The exposure levels in the treatment room during operation of the Gamma Unit ranged from 10-90000 μSv/hr, and in the surrounding areas they ranged from 0.2-0.8 μSv/hr. None of the area outside the treatment room exceeded the Atomic Energy Council (AEC) of the Republic of China regulation. All measured exposure levels were well below the limits established by the AEC committee.

並列關鍵字

Dosimetry ； Therapeutic radiology