[Frame-less and frame-based stereotaxy? How to choose the appropriate procedure]

Abstract

In recent years, additional tools for image guided surgery have been developed. Devices are now available for frameless punction and biopsy of intracerebral lesions and the indications for frameless and frame-based stereotaxy are increasingly overlapping. The objective of our paper was to analyse the most important factors that influence the decision on when to use frameless and when frame-based stereotaxy. Criteria such as application accuracy, image information and ergonomics were investigated for different lesions. Frameless and frame-based stereotaxy are complementary systems with different indications. They are different in terms of image information and ergonomics. Image guided surgery is the standard for continuous 3-dimensional topographical orientation. With high quality images (1 mm slice thickness) and bone marker registration, frameless stereotaxy may achieve an application accuracy comparable to frame-based systems. However, when using adhaesively mounted skin fiducials for patient registration, frameless stereotaxy is less accurate than framebased systems. Therefore, the size of the lesion should exceed 10 mm for punction and biopsy with a frameless system. Frame-based stereotaxy remains the gold standard for accurate targeting of lesions < 10 mm and for functional procedures.