嚥下ビデオ透視検査時の患者と検査者の放射線被曝線量を推定するため, 線量測定用ファントムを用いて線量を測定した。患者の皮膚表面線量にあたるファントム表面での線量は, 透視1分間につき3.19～4.55mGyであった。検査1回あたりの線量は, 胸部直接撮影より多いが胃撮影や頭部CTより少なかった。検査者の位置での線量は, 鉛入りエプロンなどで防護をしないことを想定した場合で, 1時間につき0.13～0.46mSvであった。防護用具なしに43～151回の検査を行なった時の検査者の被曝線量が, 一般公衆の年間線量限度に相当することになる。したがって, 検査者の被曝線量が一般公衆の線量限度を超えることは通常ないと考えられるが, 患者と検査者の被曝を最低限に抑えるために, 放射線防護の努力が必要である。

In order to estimate radiation exposure doses for the patient and the examiner from the videofluorographic examination of swallowing, we conducted a dosimetric experiment using a cubic phantom. The estimated exposure doses for the patient at the skin surface, which were measured with thermoluminescent dosimeters placed in the patient's position, were 3.19～4.55mGy per minute, and the doses per examination were higher than those from chest radiography but lower than those from stomach radiography or head computed tomography. The estimated exposure doses for the examiner without wearing any radiation protection equipment such as a lead apron, which were measured with a sievertmeter placed in the examiner's position, were 0.13～0. 46mSv per hour. Although the examiner's exposure doses are unlikely to exceed the legal dose limit for the general public, it is essential to endeavor to keep radiation exposure to a minimum for both the patient and the examiner.

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