PROBLEM TO BE SOLVED: To surely prevent remaining of medical gauze and the like in a body after a surgical operation with equipment cheaper and easier than the one using a non-contact IC tag by surely and easily performing counting of radiation contrast materials such as the medical gauze and the like.SOLUTION: By using fluoroscopic imaging means having a radiation source 1 generating a radiation and a radiation detector 4 detecting the radiation penetrating a subject group 101, the subject group 101 consisting of a plurality of subjects 102 respectively having the prescribed number of filamentous contrast materials is imaged from a plurality of directions, a three-dimensional image is reconstructed from the two-dimensional distribution of the radiation dose detected by the radiation detector 4, an image of the contrast materials is extracted, the whole length (L) of the contrast materials is calculated by dividing the total volume (V) of the contrast materials by the average cross-sectional area (t2) of the contrast materials, and the whole length (L) is divided by the length (l) of already-known one contrast material to calculate the number of contrast materials.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2016,JPO&INPIT【課題】医療用ガーゼ等の放射線造影材を確実、容易な計数を可能とし、非接触ICタグを用いるより安価、簡易な設備により、外科手術終了後の体内への医療用ガーゼ等の取り残しを確実に防止する。【解決手段】放射線を発生する放射線源1及び被検体群101を透過した放射線を検出する放射線検出器4を有する透視撮像手段を用い、それぞれが所定の数の糸状の造影材を有する複数の被検体102からなる被検体群101を複数の方向から撮像し、放射線検出器4により検出された放射線量の二次元分布から三次元画像を再構成し、造影材の像を抽出し、造影材の総体積(V)を造影材の平均断面積(t2)によって除して造影材の全長(L)を算出し、この全長(L)を既知の造影材の1本の長さ(l)によって除し、造影材の本数を算出する。【選択図】図1
