Feasibility of ultrashort echo time images using full-wave acoustic and thermal modeling for transcranial MRI-guided focused ultrasound (tcMRgFUS) planning.

Feasibility of ultrashort echo time images using full-wave acoustic and thermal modeling for transcranial MRI-guided focused ultrasound (tcMRgFUS) planning. Phys Med Biol. 2019 Mar 25;: Authors: Guo S, Zhuo J, Li G, Gandhi D, Dayan M, Fishman PS, Eisenberg HM, Melhem ER, Gullapalli RP Abstract Transcranial MRI-guided focused ultrasound (tcMRgFUS) is increasingly used to non-invasively treat a wide variety of neurological disorders including essential tremors, Parkinson disease and neuropathic pain. Although this treatment is an MRI-guided procedure, the current pre-treatment screening and planning involve a CT of the head to obtain three-dimensional skull images. These images are necessary for estimating the proportion of absorbed energy and the acoustic phase shift associated with the skull and determining the transmit energy of ultrasonic wave to create thermal lesions at a desired focal spot. Ultrashort Echo Time (UTE) MR sequences are able to capture signals from tissues such as bone which has a very short transverse relaxation time. In this manuscript, we assess the use of a UTE based sequence to image the calvarium and test the feasibility of obviating the need for CT based imaging during an MR-guided focused ultrasound therapy. We demonstrate that the segmentation of bone using UTE images leads to similar skull density ratio values as determined from CT with high correlation (r=0.88; p<0,0001). Furthermore, through trea...
Source: Physics in Medicine and Biology - Category: Physics Authors: Tags: Phys Med Biol Source Type: research