HEAD REGISTRATION TECHNIQUES FOR IMAGE-GUIDED SURGERY

Localization of the pathological structures in relation to the surroun ding anatomy and understanding of the surgical anatomy are probably th e most important keys to successful neurosurgery. Image-guided surgery is an important tool for understanding an individual's anatomy and fo r precisely locating the lesion. Head registration is the most importa nt step in image-guided surgery, required by every system in use today , although these systems show great differences. In this study, head r egistration techniques and user algorithms in 83 image-guided surgery cases were analyzed. Several types of fiducials including skin markers , bone fiducials, and the stereotactic frame were used for registratio n. Clinical applications, ease of use, and computer-calculated accurac y values for each type were compared. The average accuracy was 1.50 mm . X-spot skin markers are the fiducials most commonly used with CT sca n. The stereotactic frame was the most accurate method, with an accura cy of 0.69 mm. Disc-shaped fiducials were used when MRI was the imagin g modality; they provided an average accuracy of 2.62mm. Head registra tion is an important part of image-guided surgery; the procedure used for registration should be based on the requirements of each individua l case. Our results indicated that the stereotactic frame is the most accurate method of registration; however, skin markers provide reasona ble accuracy with significant ease of use and patient comfort.