软组织内金属异物存留是很常见的临床问题。在取除异物时常常由于定位不准而使手术时间延长,甚至导致手术失败。过去最常用的定位法是通过异物部位的正侧位X线平片,进行分析定位,甚至在X线透视下进行手术,此种两维定位误差率很高,病人及医务人员受X线伤害较多。为解决这一问题, The retention of metallic foreign bodies in soft tissue is a very common clinical problem. In the removal of foreign objects often because of positioning is not allowed to extend the operation time, and even lead to surgical failure. In the past the most commonly used positioning method is through the foreign body part of the lateral X-ray plain film for analysis and positioning, and even under X-ray surgery, the two-dimensional positioning error rate is high, the patient and medical staff X-ray injury More. To solve this problem,