dual guidance

Dual guidance

• For skeletal minimally invasive technique, the best and safest guidance technique seems to be combined CT and fluoroscopy (Gangi et al. 1995). This combination allows precise needle placement, reduces complications and increases the comfort of the operator. The dual guidance technique using CT and C-arm fluoroscopy is particularly interesting in percutaneous cementoplasty (Gangi et al 1994, Gangi et al 1995). A mobile C-arm is positioned in front of the CT gantry.

Figure 6a. Dual guidance CT and fluoroscopy .	Figure 6b. Dual guidance fluoroscopy and CT.

• However, fluoroscopy and biplane fluoroscopy can be used for PC by well-trained radiologist if access to the CT room is difficult (Cotten et al. 1996, Debusshe-Depriester et al. 1991). To address these concerns on a routine basis, a combination of CT and fluoroscopy for interventional procedures has been recommended.
• For fluoroscopy, a mobile C-arm is used, positioned in front of the CT-gantry. By using a rotating fluoroscope and CT, the structure to be punctured can be visualized three dimensionally and with exact differentiation of anatomic structures, which in many cases is not possible with fluoroscopy alone. Two mobile monitors are placed in front of the physician, displaying the last stored image and the fluoroscopic image. The operator can switch from CT to fluoroscopy and vice versa at any time as shown in the dual guidance movie. In percutaneous vertebroplasty, the intervention begins with CT and is followed by fluoroscopy. The needle is placed precisely and safely under CT guidance. The injection of the methyl methacrylate requires real-time imaging and is therefore performed under fluoroscopic control as shown in the cement injection movie cases. This combination has many advantages. The possibilities of the simultaneous combination of the two imaging methods are almost unlimited and other applications in interventional radiology are possible .