<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin-top:0in;
margin-right:0in;
margin-bottom:10.0pt;
margin-left:0in;
line-height:115%;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";}
span.EmailStyle19
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:windowtext;}
span.EmailStyle20
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:#1F497D;}
span.EmailStyle21
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal;page-break-after:avoid'><b><span style='font-size:16.0pt;font-family:"Tahoma","sans-serif"'>PhD Dissertation Defense<o:p></o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-family:"Tahoma","sans-serif"'><o:p> </o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:14.0pt;font-family:"Tahoma","sans-serif"'>Numerical and Experimental Study of MRI RF Signal Interactions with Various Medical Devices <o:p></o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:14.0pt;font-family:"Tahoma","sans-serif"'><br>Yan Liu<o:p></o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:13.0pt;font-family:"Tahoma","sans-serif"'><o:p> </o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:12.0pt'>Date: Monday, November 26th, 2012<o:p></o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:13.0pt;font-family:"Tahoma","sans-serif"'><o:p> </o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:12.0pt'>Location:</span></b><span style='font-size:12.0pt'> ECE</span><span style='font-size:12.0pt'> Conference Room<o:p></o:p></span></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:12.0pt'>Time: </span></b><span style='font-size:12.0pt'>10:00 am<b> </b><o:p></o:p></span></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:13.0pt;font-family:"Tahoma","sans-serif"'><o:p> </o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:12.0pt'>Committee Chair: </span></b><span style='font-size:12.0pt'>Dr. Ji Chen<b><o:p></o:p></b></span></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:12.0pt'><o:p> </o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><b><span style='font-size:12.0pt'>Committee Members: <o:p></o:p></span></b></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'>Dr. Driss Benhaddou<o:p></o:p></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><span style='font-size:12.0pt'>Dr. David Jackson<o:p></o:p></span></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'>Dr. Donald Wilton<o:p></o:p></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'>Dr. George Zouridakis<o:p></o:p></p><p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt;line-height:normal'><o:p> </o:p></p><p class=MsoNormal align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:center;line-height:normal'><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt;text-indent:.5in;line-height:normal'><span style='font-size:12.0pt'>With the increased use of implantable medical devices and the fast spread of the Magnetic Resonance Imaging (MRI), safety in MRI systems. The interaction between the fields generated by the MRI system; there have been concerns of the device compatibility and medical devices implanted in the patient’s body could produce magnetically-induced displacement force and torque, radio frequency (RF) heating, image artifact and some electromagnetic compatibility problems on both active, and passive implanted medical devices. While most devices are manufactured using non-magnetic materials which efficiently control the displacement force and torque at a safety level, the RF induced heating near the devices becomes a primary safety issue.<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt;text-indent:.5in;line-height:normal'><span style='font-size:12.0pt'> <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt;text-indent:.5in;line-height:normal'><span style='font-size:12.0pt'>In this work, the first topic is the RF heating for passive medical devices. Electromagnetic simulation using the Finite Difference Time Domain (FDTD) method and thermal simulation are applied to understand potential temperature increase inside the human body when the patient with the implantable device undergoes the MR scanner. Measurements are performed to validate simulation results. <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt;text-indent:.5in;line-height:normal'><span style='font-size:12.0pt'><o:p> </o:p></span></p><p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt;text-indent:.5in;line-height:normal'><span style='font-size:12.0pt'>The second topic is the RF heating for active implantable medical devices (AIMDs). It is studied using alternative approaches due to the fine features inside leads attached to AIMDs. The third topic covers the measurement uncertainty of using fiber optic thermal probes in RF heating assessment. The fiber optic probes which are used to measure temperature rise around the medical device can lead to significant temperature variation from the original temperature without probes. Three medical devices have been investigated to quantify the effect on temperature rise change due to the existence of thermal probes. It is found thermal probes have more influence on the temperature rise around small and tiny structures such as screws and leads.<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:0in;margin-bottom:.0001pt;line-height:normal'><span style='font-size:12.0pt'><o:p> </o:p></span></p></div></body></html>