臨床上性腺的防護都是使用鉛片,但常因鉛遮蔽片遮蔽住臨床需要診斷的位置而導致重照,因此我們以鉍遮蔽片應用在X光防護上,測試鉍遮蔽片應用在骨盆X光防護的效果。實驗照相時,分別採用不同的防護片遮蔽作為測試,並與未使用遮蔽片對照組做劑量比對,測量不同材質之遮蔽片與不同厚度鉍遮蔽片,對於輻射防護的效果。實驗數據顯示,使用傳統鉛遮蔽片時,性腺可降低67.45%的劑量,而使用一片、兩片、三片、四片鉍遮蔽片時,性腺可降低的劑量分別為73.85%、81.06%、86.50%、97.68%。使用鉍遮蔽片雖可以降低輻射劑量,但仍須正視影像品質。影像品質的判定是以三位實際從事小兒骨科醫師做為影像判讀,經三位醫師判讀後,三位醫師均認為遮蔽一片與二片鉍遮蔽片影像品質都可符合臨床診斷,遮蔽三片及四片鉍遮蔽片時,有醫師認為影像不佳。實驗結果顯示,使用鉍遮蔽片對於臨床性腺的防護遠優於使用傳統鉛片,且因鉍遮蔽片下方影像清楚可見,重照機率低,將可應用於臨床防護上。
Clinically, lead is used for shielding over children's gonad area during radiography, but some of the images often need to be re-taken due to insufficient diagnostic information obscured by lead gonadal shields. Therefore, Bismuth shielding is evaluated for radiation protection, especially over pelvis radiography. In this research, pelvis radiographs with different shielding both in materials and thicknesses are acquired and compared with the ones without shielding to explore the influence on image quality and the reduction of radiation dose. The statistical analysis of our experiments indicates that the radiation dose reduction by traditional lead gonadal shielding is 67.45% whereas the reduction by one layer of bismuth shielding is 73.85%. Then, the reduction is increased to 81.06% after two layers of bismuth shielding are applied. When three and four layers of bismuth shielding are used in the experiment, the radiation dose are greatly reduced to 86.50% and 97.68%. It's clear that the more layers of bismuth are applied, the better radiation dose reduction is achieved. Nevertheless, image quality is equally essential in radiography. In this research, all the images are viewed and evaluated by three pediatric orthopedic practitioners separately. After careful examination, they all agree that the images with both one layer and two layers of bismuth shielding can provide adequate diagnostic information whereas the images with three layers or four layers of bismuth shielding fail to do so. The experiment shows that the application of bismuth shielding is superior than lead shielding over gonad area during clinic radiography in providing better image quality and reducing the repetition of radiographic examination.