Piovan E, Dal Sasso M, Urbani G P, Sartori R, Foroni R, Benati A
Verona University Hospital, Italy.
Stereotact Funct Neurosurg. 1996;66 Suppl 1:57-62. doi: 10.1159/000099802.
Images coming from digital subtraction angiography (DSA) are affected by a perspective distortion due to the use of image intensifiers. As a result, DSA cannot be used for the accurate definition of stereotactic coordinates. A correction method has been developed to enable the use of DSA for the radiosurgery of arteriovnous malformations. A software program and a special phantom tool were employed. The phantom is made by a computer-controlled drilling machine which makes holes in a Plexiglas plate. It has 865 calibration steel spheres with coordinates determined with a precision of 0.01 mm. A calibration image is acquired by a personal computer, and the software calculates the transformation algorithm to superimpose the image on the known positions of the phantom. This algorithm is saved and then recalled to transform the diagnostic images.
由于使用图像增强器，数字减影血管造影（DSA）产生的图像会受到透视畸变的影响。因此，DSA不能用于精确确定立体定向坐标。已开发出一种校正方法，使DSA能够用于动静脉畸形的放射外科治疗。使用了一个软件程序和一种特殊的体模工具。该体模由一台计算机控制的钻孔机制作，在有机玻璃板上钻孔。它有865个校准钢球，其坐标测定精度为0.01毫米。通过个人计算机获取校准图像，软件计算变换算法，将图像叠加到体模的已知位置上。该算法被保存，然后调用以变换诊断图像。
