%0 Journal Article
%T A Simple and Inexpensive Stereotactic Guidance Frame for MRI-Guided Brain Biopsy in Canines
%A Alexander D. Squires
%A Yabiao Gao
%A Sean F. Taylor
%A Marc Kent
%A Zion Tsz Ho Tse
%J Journal of Medical Engineering
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/139535
%X A magnetic resonance imaging (MRI) guided stereotactic system was developed to provide veterinarians a method to accomplish minimally invasive stereotactic brain biopsies and procedures involving the cerebrum in canines. While MR-guided procedures are prevalent for humans, they are less common in animal practices. The system was designed to minimize fabrication costs in an effort to make such procedures more accessible in the veterinary field. A frame constrained the head without the need for punctures and supported registration and guidance attachments. Location data for registration and relevant structures were selected by the clinician, and a reverse kinematic analysis program generated the settings of the stereotactic arch to guide a needle to the desired location. Phantom experiments and three cadaver trials showed an average targeting error of <3£¿mm using the system. 1. Introduction Magnetic resonance imaging (MRI) is widely used in medical research and practice due to its ability to peer inside biological organisms with superior image quality, providing high-quality soft tissue imaging while not exposing patients to potentially ionizing radiation or contrast agents [1]. Advances in MRI technology have led to numerous studies and the development of MR-guided treatment techniques [2]. Of particular interest here is the prevalence of MR-guided brain biopsy procedures [3¨C14] as well as similar procedures performed via computed tomography (CT) [15¨C18]. Utilizing MRI to perform brain biopsies in humans is common, but in canine subjects tumor diagnosis is most commonly performed postmortem. Naturally, such timing does not help the patient, and access to tumors in vivo is desirable. Image-based diagnosis by itself provides less certainty, and open-skull biopsies require a sizable amount of tissue and bone to be damaged or removed; both cases have their drawbacks [17]. Stereotactic procedures can be much superior, thanks to their precise targeting abilities and the small size of holes in tissue and bone which are required, causing tissue to be minimally damaged. Inside an MR suite, use of certain materials will degrade image quality and/or endanger the safety of a patient [19]. For this reason, any device which operates on electromagnetic principles (such as common electric motors or relays) is not compatible with the MR environment [20]. Thus, actuation of devices inside the MR suite must be powered using other means, often via pneumatics or piezoceramics [21]. Additionally, any ferro-/paramagnetic materials are banned for safety reasons [19, 20, 22].
%U http://www.hindawi.com/journals/jme/2014/139535/