磁疗磁场分布测量及剂量表达方法

Measurement of magnetic field distribution and expression of dosage in magnetic treatment

目的:探讨磁疗剂量的表达方法。方法:用特斯拉计的测试探头测量记录磁片和线圈周围空间各点的磁场强度。①直径16cm圆电磁线圈通以直流电流3A,在距线圈表面不同距离及距中线轴不同距离点的磁场强度。②边长42cm×42cm的矩形电磁线圈通以直流电流2A,在距线圈表面不同距离及距中线轴不同距离点(平行于矩形的一边)的磁场强度。③两个边长42cm×42cm的矩形电磁线圈相距30cm相对平行放置,通以直流电流2A,在距其中一个线圈表面0～15cm距离范围及距中线轴不同距离点(平行于矩形的一边)的磁场强度。结果:几种治疗用磁片和线圈周围的磁场分布各不相同;磁片的磁场衰减很快,在距磁片表面1cm处就下降为最大值的2%。直径为16cm的线圈,在距线圈表面3cm磁场强度约下降一半。单个边长42cm×42cm的矩形电磁线圈,在距线圈表面11cm时磁场强度约下降一半。两个矩形线圈相对30cm对置时在两线圈之间区域的磁场强度基本均匀。结论:用某一点的磁场强度不能表达整个磁疗范围的磁场特性,磁疗剂量的表达方法要描述:①磁疗磁片或线圈的空间磁场强度分布。②磁疗磁片或线圈和治疗部位间的相对位置。③磁场随时间变化的波形。

AIM： To study the expression of dose in magnetic treatment. METHODS： Using the magnetometer to measure the magnetic field distribution of the flakelet magnet and the electromagnetic coil, ①The value of magnetic field was measured at different distance to the electromagnetic coil and axon of median line of diameter 16 era flowing direct current 3 A. ②The value of magnetic field was measured at different distance （paralleled to one side of rectangle） to the electromagnetic coil and axon of .median line of the rectangle electromagnetic coil of sideline 42 era ×42 eva flowing direct current 2 A. ③The value of magnetic field was measured at different points to 0-15 cm of electromagnetic coil and axon of median line between two rectangle electromagnetic coils （30 cm） （paralleled to one side of rectangle） of sideline 42 cm×42 cm flowing direct current 2 A. RESULTS： The magnetic field distributions of the magnet and the electromagnetic coil were different, The attenuation of the magnetic field of the flakelet magnetic was very rapid, and the value of magnetic field at the distance to the magnet surface 1 cm was 2% of the maximum. The value of magnetic field of the electromagnetic coil of diameter 16 cm at the distance to the coil surface 3 cm was about half of the maximum. The value of magnetic field of the foursquare electromagnetic coil of sideline 42 cm×42 cm at the distance to the coil surface 11 cm was about half of the maximum. The value of magnetic field between two foursquare electromagnetic coils was uniformity on the whole at 30 cm. CONCLUSION： The density of magnetic field at one point cannot express the dose in magnetic treatment. The expression of dose in nmgnetic treatment includes the following： ①The magnetic field distribution of the magnet or the electromagnetic coil. ②The relative position of the magnet or the electromagnetic coil and the treatment range. ③The waves of magnetic field varying with the time.