Real time estimation of brain tissue dislocation and deformation : a phantom study
Kuruvilla, V. J.
Date of Issue2013
School of Mechanical and Aerospace Engineering
The main source of error during targeting of abnormalities in the brain during surgery is the phenomenon of brain shift. Brain shift makes the pre-operative treatment plan, which is developed based on the pre-operative images, outdated during the course of the surgery. Hence, there is a need to accurately estimate the brain tissue shift and to update the treatment plan in real time. In this paper, a method is proposed to track the dislocations and deformations of the brain tissue in real time using various image processing techniques with the objective of updating on-line planning for non-invasive procedures such as tissue ablation using High Intensity Focused Ultrasound (HIFU). The energy delivery is planned through a precise craniotomy by coupling HIFU source(s) directly on to dura-mater without opening it (thereby, non-invasive to brain tissue). Coherent Point Drift method is used for the non-rigid registration of ultrasound images in a suitably designed skull and brain phantoms. The method gave a maximum rms error of less than 4.582 mm and the computation took approximately 72.7 seconds, which is sufficient in the context of HIFU based ablation of point-by-point lesioning in the targeted regions. For the estimation of the dislocation of a targeted feature in the phantom, a correlation method, for ultrasound reference image to subsequent on-line images is proposed. Various laboratory trials showed a maximum error of 0.4 mm and an average computation time of under 0.5 seconds.
Journal of medical imaging and health informatics
© 2013American Scientific Publishers.