| dc.contributor.advisor | pichardo, samuel | |
| dc.contributor.author | macdonald, matthew a. | |
| dc.date.accessioned | 2019-12-05t20:43:10z | |
| dc.date.available | 2019-12-05t20:43:10z | |
| dc.date.created | 2016 | |
| dc.date.issued | 2016 | |
| dc.identifier.uri | http://knowledgecommons.lakeheadu.ca/handle/2453/4527 | |
| dc.description.abstract | magnetic resonance image (mri)-guided interventions involving percutaneous biopsies of
lesions, or trajectory alignment with prospective stereotaxy are conducted in real time using rapid
image acquisition. a mechanism of passively localizing a device and calculating its orientation
is desired to improve interventional outcomes in these situations. in this work, we propose and
evaluate an image-based technique to determine the position and alignment of a linearly shaped
interventional device within an ex-vivo tissue specimen. low resolution 3d orientation scan data
is processed to produce a virtual line tting using principal component analysis. the line tting
algorithm was incorporated into a biopsy needle tracking system implemented with an mrscanner
operated using a footswitch. a gui application was written to collect foot pedal input
and display automated visualization of device placement inside the scanner room. placement time
trials (n=3) conducted with this system using porcine muscle and phantom samples suspended
in rigid frames with inserted gadolinium-enhanced targets. the mean targeting error across
all directions was 3:6 mm and 5:1 mm for the phantom trials and ex-vivo trials respectively.
the average entry-to-target time was 247 sec. device localization during trials was adequate to
contain a 11-gauge titanium biopsy needle within a visualization slice volume of 10 mm after
93:8% of alignments over insertion lengths between 30 mm to 110 mm at insertion angles between
1:4 to 20 from the static magnetic eld and frequency encoding axes. practical considerations
were identi ed and occupational exposure measurements were collected as part of determining
the system's overall feasibility. | en_us |
| dc.language.iso | en_us | en_us |
| dc.subject | magnetic resonance image (mri)-guided interventions | en_us |
| dc.title | a mechanism for simplified scanner control with application to mri-guided interventions | en_us |
| dc.type | thesis | en_us |
| etd.degree.name | master of science | en_us |
| etd.degree.level | master | en_us |
| etd.degree.discipline | engineering : electrical and computer | en_us |
| etd.degree.grantor | 阿根廷vs墨西哥竞猜
| en_us |
