Quantification of arterial plaque and lumen density with MDCT
Purpose: This study aimed to derive a mathematical correction function in order to normalize the CT number measurements for small volume arterial plaque and small vessel mimicking objects, imaged with multidetector CT (MDCT). Methods: A commercially available calcium plaque phantom (QRM GmbH, Moehre...
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| Veröffentlicht in: | Medical physics (Lancaster) 2010-08, Vol.37 (8), p.4227-4237 |
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| creator | Paul, Narinder S. Blobel, Joerg Kashani, Hany Rice, Murray Ursani, Ali |
| description | Purpose:
This study aimed to derive a mathematical correction function in order to normalize the CT number measurements for small volume arterial plaque and small vessel mimicking objects, imaged with multidetector CT (MDCT).
Methods:
A commercially available calcium plaque phantom (QRM GmbH, Moehrendorf, Germany) and a custom built cardiovascular phantom were scanned with 320 and 64 MDCT scanners. The calcium hydroxyapatite plaque phantom contained objects 0.5–5.0 mm in diameter with known CT attenuation nominal values ranging 50–800 HU. The cardiovascular phantom contained vessel mimicking objects 1.0–5.0 mm in diameter with different contrast media. Both phantoms were scanned using clinical protocols for CT angiography and images were reconstructed with different filter kernels. The measured CT number (HU) and diameter of each object were analyzed on three clinical postprocessing workstations. From the resultant data, a mathematical formula was derived based on absorption function
exp
(
−
μ
∗
d
)
to demonstrate the relation between measured CT numbers and object diameters.
Results:
The percentage reduction in measured CT number (HU) for the group of selected filter kernels, apparent during CT angiography, is dependent only on the object size (plaque or vessel diameter). The derived formula of the form
1
−
c
∗
exp
(
−
a
∗
d
^
b
)
showed reduction in CT number for objects between 0.5 and 5 mm in diameter, with asymptote reaching background noise for small objects with diameters nearing the CT in-plane resolution (0.35 mm). No reduction was observed for the objects with diameters equal or larger than 5 mm.
Conclusions:
A clear mathematical relationship exists between object diameter and reduction in measured CT number in HU. This function is independent of exposure parameters and inherent attenuation properties of the objects studied. Future developments include the incorporation of this mathematical model function into quantification software in order to automatically generate a true assessment of measured CT number (HU) corresponding to plaque physical density
ρ
(
g
/
cm
3
)
. This is a significant development for the accurate, noninvasive classification of noncalcified arterial plaque. |
| doi_str_mv | 10.1118/1.3447725 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_osti_</sourceid><recordid>TN_cdi_osti_scitechconnect_22096753</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>756297352</sourcerecordid><originalsourceid>FETCH-LOGICAL-c4755-e5e1ea783183fec67f3ac72412425021448fe1d881a5da742b3c2faf093708953</originalsourceid><addsrcrecordid>eNp9kV1LHDEUhoNUdLVe-AfKQC-KwmzzuclctCDrV2GlFfQ6xMwJpsxOtknGZf-9s51VlLK9ys2T55z3PQgdEzwmhKivZMw4l5KKHTSiXLKSU1x9QCOMK15SjsU-OkjpN8Z4wgTeQ_sUK1kJxUbo221n2uydtyb70BbBFSZmiN40xaIxfzooTFsXTTeHtqihTT6viqXPj8XN-fTuI9p1pklwtHkP0f3lxd30upz9vPoxPZuVlkshShBAwEjFiGIO7EQ6ZqyknFBOBaaEc-WA1EoRI2ojOX1gljrjcMUkVpVgh-jz4A0pe52sz2AfbWhbsFnTPuxECtZTXwZqEUO_eMp67pOFpjEthC5pKSa0kkzQnjwZSBtDShGcXkQ_N3GlCdbrSjXRm0p79tPG2j3MoX4lXzrsgXIAlr6B1XaTvvm1EX4f-HWOv61v__P-Ojo4bWIvON0meArxzcBF7f4H_5v1GbHVrW8</addsrcrecordid><sourcetype>Open Access Repository</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>756297352</pqid></control><display><type>article</type><title>Quantification of arterial plaque and lumen density with MDCT</title><source>MEDLINE</source><source>Wiley Online Library All Journals</source><source>Alma/SFX Local Collection</source><creator>Paul, Narinder S. ; Blobel, Joerg ; Kashani, Hany ; Rice, Murray ; Ursani, Ali</creator><creatorcontrib>Paul, Narinder S. ; Blobel, Joerg ; Kashani, Hany ; Rice, Murray ; Ursani, Ali</creatorcontrib><description>Purpose:
This study aimed to derive a mathematical correction function in order to normalize the CT number measurements for small volume arterial plaque and small vessel mimicking objects, imaged with multidetector CT (MDCT).
Methods:
A commercially available calcium plaque phantom (QRM GmbH, Moehrendorf, Germany) and a custom built cardiovascular phantom were scanned with 320 and 64 MDCT scanners. The calcium hydroxyapatite plaque phantom contained objects 0.5–5.0 mm in diameter with known CT attenuation nominal values ranging 50–800 HU. The cardiovascular phantom contained vessel mimicking objects 1.0–5.0 mm in diameter with different contrast media. Both phantoms were scanned using clinical protocols for CT angiography and images were reconstructed with different filter kernels. The measured CT number (HU) and diameter of each object were analyzed on three clinical postprocessing workstations. From the resultant data, a mathematical formula was derived based on absorption function
exp
(
−
μ
∗
d
)
to demonstrate the relation between measured CT numbers and object diameters.
Results:
The percentage reduction in measured CT number (HU) for the group of selected filter kernels, apparent during CT angiography, is dependent only on the object size (plaque or vessel diameter). The derived formula of the form
1
−
c
∗
exp
(
−
a
∗
d
^
b
)
showed reduction in CT number for objects between 0.5 and 5 mm in diameter, with asymptote reaching background noise for small objects with diameters nearing the CT in-plane resolution (0.35 mm). No reduction was observed for the objects with diameters equal or larger than 5 mm.
Conclusions:
A clear mathematical relationship exists between object diameter and reduction in measured CT number in HU. This function is independent of exposure parameters and inherent attenuation properties of the objects studied. Future developments include the incorporation of this mathematical model function into quantification software in order to automatically generate a true assessment of measured CT number (HU) corresponding to plaque physical density
ρ
(
g
/
cm
3
)
. This is a significant development for the accurate, noninvasive classification of noncalcified arterial plaque.</description><identifier>ISSN: 0094-2405</identifier><identifier>EISSN: 2473-4209</identifier><identifier>DOI: 10.1118/1.3447725</identifier><identifier>PMID: 20879583</identifier><identifier>CODEN: MPHYA6</identifier><language>eng</language><publisher>United States: American Association of Physicists in Medicine</publisher><subject>Absorptiometry, Photon - instrumentation ; Absorptiometry, Photon - methods ; ABSORPTION ; Angiography ; APATITES ; arterial plaque ; Arteries - physiopathology ; Atherosclerosis - diagnostic imaging ; Atherosclerosis - physiopathology ; BACKGROUND NOISE ; BIOMEDICAL RADIOGRAPHY ; blood vessels ; Calcium ; calcium compounds ; CALCIUM PHOSPHATES ; Calibration ; cardiovascular system ; CLASSIFICATION ; Computed tomography ; COMPUTER CODES ; Computer Simulation ; Computer software ; computerised tomography ; COMPUTERIZED TOMOGRAPHY ; CONTRAST MEDIA ; CORONARIES ; CT coronary angiography ; diagnostic radiography ; Humans ; image reconstruction ; KERNELS ; medical image processing ; Medical image reconstruction ; Medical imaging ; Models, Cardiovascular ; Numerical modeling ; PHANTOMS ; Phantoms, Imaging ; Radiographic Image Interpretation, Computer-Assisted - methods ; Radiography ; RADIOLOGY AND NUCLEAR MEDICINE ; Reconstruction ; Tomography, X-Ray Computed - instrumentation ; Tomography, X-Ray Computed - methods ; Vacuum tubes ; Vascular system ; X‐ray imaging</subject><ispartof>Medical physics (Lancaster), 2010-08, Vol.37 (8), p.4227-4237</ispartof><rights>American Association of Physicists in Medicine</rights><rights>2010 American Association of Physicists in Medicine</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c4755-e5e1ea783183fec67f3ac72412425021448fe1d881a5da742b3c2faf093708953</citedby><cites>FETCH-LOGICAL-c4755-e5e1ea783183fec67f3ac72412425021448fe1d881a5da742b3c2faf093708953</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://onlinelibrary.wiley.com/doi/pdf/10.1118%2F1.3447725$$EPDF$$P50$$Gwiley$$H</linktopdf><linktohtml>$$Uhttps://onlinelibrary.wiley.com/doi/full/10.1118%2F1.3447725$$EHTML$$P50$$Gwiley$$H</linktohtml><link.rule.ids>230,314,780,784,885,1417,27924,27925,45574,45575</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/20879583$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink><backlink>$$Uhttps://www.osti.gov/biblio/22096753$$D View this record in Osti.gov$$Hfree_for_read</backlink></links><search><creatorcontrib>Paul, Narinder S.</creatorcontrib><creatorcontrib>Blobel, Joerg</creatorcontrib><creatorcontrib>Kashani, Hany</creatorcontrib><creatorcontrib>Rice, Murray</creatorcontrib><creatorcontrib>Ursani, Ali</creatorcontrib><title>Quantification of arterial plaque and lumen density with MDCT</title><title>Medical physics (Lancaster)</title><addtitle>Med Phys</addtitle><description>Purpose:
This study aimed to derive a mathematical correction function in order to normalize the CT number measurements for small volume arterial plaque and small vessel mimicking objects, imaged with multidetector CT (MDCT).
Methods:
A commercially available calcium plaque phantom (QRM GmbH, Moehrendorf, Germany) and a custom built cardiovascular phantom were scanned with 320 and 64 MDCT scanners. The calcium hydroxyapatite plaque phantom contained objects 0.5–5.0 mm in diameter with known CT attenuation nominal values ranging 50–800 HU. The cardiovascular phantom contained vessel mimicking objects 1.0–5.0 mm in diameter with different contrast media. Both phantoms were scanned using clinical protocols for CT angiography and images were reconstructed with different filter kernels. The measured CT number (HU) and diameter of each object were analyzed on three clinical postprocessing workstations. From the resultant data, a mathematical formula was derived based on absorption function
exp
(
−
μ
∗
d
)
to demonstrate the relation between measured CT numbers and object diameters.
Results:
The percentage reduction in measured CT number (HU) for the group of selected filter kernels, apparent during CT angiography, is dependent only on the object size (plaque or vessel diameter). The derived formula of the form
1
−
c
∗
exp
(
−
a
∗
d
^
b
)
showed reduction in CT number for objects between 0.5 and 5 mm in diameter, with asymptote reaching background noise for small objects with diameters nearing the CT in-plane resolution (0.35 mm). No reduction was observed for the objects with diameters equal or larger than 5 mm.
Conclusions:
A clear mathematical relationship exists between object diameter and reduction in measured CT number in HU. This function is independent of exposure parameters and inherent attenuation properties of the objects studied. Future developments include the incorporation of this mathematical model function into quantification software in order to automatically generate a true assessment of measured CT number (HU) corresponding to plaque physical density
ρ
(
g
/
cm
3
)
. This is a significant development for the accurate, noninvasive classification of noncalcified arterial plaque.</description><subject>Absorptiometry, Photon - instrumentation</subject><subject>Absorptiometry, Photon - methods</subject><subject>ABSORPTION</subject><subject>Angiography</subject><subject>APATITES</subject><subject>arterial plaque</subject><subject>Arteries - physiopathology</subject><subject>Atherosclerosis - diagnostic imaging</subject><subject>Atherosclerosis - physiopathology</subject><subject>BACKGROUND NOISE</subject><subject>BIOMEDICAL RADIOGRAPHY</subject><subject>blood vessels</subject><subject>Calcium</subject><subject>calcium compounds</subject><subject>CALCIUM PHOSPHATES</subject><subject>Calibration</subject><subject>cardiovascular system</subject><subject>CLASSIFICATION</subject><subject>Computed tomography</subject><subject>COMPUTER CODES</subject><subject>Computer Simulation</subject><subject>Computer software</subject><subject>computerised tomography</subject><subject>COMPUTERIZED TOMOGRAPHY</subject><subject>CONTRAST MEDIA</subject><subject>CORONARIES</subject><subject>CT coronary angiography</subject><subject>diagnostic radiography</subject><subject>Humans</subject><subject>image reconstruction</subject><subject>KERNELS</subject><subject>medical image processing</subject><subject>Medical image reconstruction</subject><subject>Medical imaging</subject><subject>Models, Cardiovascular</subject><subject>Numerical modeling</subject><subject>PHANTOMS</subject><subject>Phantoms, Imaging</subject><subject>Radiographic Image Interpretation, Computer-Assisted - methods</subject><subject>Radiography</subject><subject>RADIOLOGY AND NUCLEAR MEDICINE</subject><subject>Reconstruction</subject><subject>Tomography, X-Ray Computed - instrumentation</subject><subject>Tomography, X-Ray Computed - methods</subject><subject>Vacuum tubes</subject><subject>Vascular system</subject><subject>X‐ray imaging</subject><issn>0094-2405</issn><issn>2473-4209</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2010</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><recordid>eNp9kV1LHDEUhoNUdLVe-AfKQC-KwmzzuclctCDrV2GlFfQ6xMwJpsxOtknGZf-9s51VlLK9ys2T55z3PQgdEzwmhKivZMw4l5KKHTSiXLKSU1x9QCOMK15SjsU-OkjpN8Z4wgTeQ_sUK1kJxUbo221n2uydtyb70BbBFSZmiN40xaIxfzooTFsXTTeHtqihTT6viqXPj8XN-fTuI9p1pklwtHkP0f3lxd30upz9vPoxPZuVlkshShBAwEjFiGIO7EQ6ZqyknFBOBaaEc-WA1EoRI2ojOX1gljrjcMUkVpVgh-jz4A0pe52sz2AfbWhbsFnTPuxECtZTXwZqEUO_eMp67pOFpjEthC5pKSa0kkzQnjwZSBtDShGcXkQ_N3GlCdbrSjXRm0p79tPG2j3MoX4lXzrsgXIAlr6B1XaTvvm1EX4f-HWOv61v__P-Ojo4bWIvON0meArxzcBF7f4H_5v1GbHVrW8</recordid><startdate>201008</startdate><enddate>201008</enddate><creator>Paul, Narinder S.</creator><creator>Blobel, Joerg</creator><creator>Kashani, Hany</creator><creator>Rice, Murray</creator><creator>Ursani, Ali</creator><general>American Association of Physicists in Medicine</general><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7X8</scope><scope>OTOTI</scope></search><sort><creationdate>201008</creationdate><title>Quantification of arterial plaque and lumen density with MDCT</title><author>Paul, Narinder S. ; Blobel, Joerg ; Kashani, Hany ; Rice, Murray ; Ursani, Ali</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c4755-e5e1ea783183fec67f3ac72412425021448fe1d881a5da742b3c2faf093708953</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2010</creationdate><topic>Absorptiometry, Photon - instrumentation</topic><topic>Absorptiometry, Photon - methods</topic><topic>ABSORPTION</topic><topic>Angiography</topic><topic>APATITES</topic><topic>arterial plaque</topic><topic>Arteries - physiopathology</topic><topic>Atherosclerosis - diagnostic imaging</topic><topic>Atherosclerosis - physiopathology</topic><topic>BACKGROUND NOISE</topic><topic>BIOMEDICAL RADIOGRAPHY</topic><topic>blood vessels</topic><topic>Calcium</topic><topic>calcium compounds</topic><topic>CALCIUM PHOSPHATES</topic><topic>Calibration</topic><topic>cardiovascular system</topic><topic>CLASSIFICATION</topic><topic>Computed tomography</topic><topic>COMPUTER CODES</topic><topic>Computer Simulation</topic><topic>Computer software</topic><topic>computerised tomography</topic><topic>COMPUTERIZED TOMOGRAPHY</topic><topic>CONTRAST MEDIA</topic><topic>CORONARIES</topic><topic>CT coronary angiography</topic><topic>diagnostic radiography</topic><topic>Humans</topic><topic>image reconstruction</topic><topic>KERNELS</topic><topic>medical image processing</topic><topic>Medical image reconstruction</topic><topic>Medical imaging</topic><topic>Models, Cardiovascular</topic><topic>Numerical modeling</topic><topic>PHANTOMS</topic><topic>Phantoms, Imaging</topic><topic>Radiographic Image Interpretation, Computer-Assisted - methods</topic><topic>Radiography</topic><topic>RADIOLOGY AND NUCLEAR MEDICINE</topic><topic>Reconstruction</topic><topic>Tomography, X-Ray Computed - instrumentation</topic><topic>Tomography, X-Ray Computed - methods</topic><topic>Vacuum tubes</topic><topic>Vascular system</topic><topic>X‐ray imaging</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Paul, Narinder S.</creatorcontrib><creatorcontrib>Blobel, Joerg</creatorcontrib><creatorcontrib>Kashani, Hany</creatorcontrib><creatorcontrib>Rice, Murray</creatorcontrib><creatorcontrib>Ursani, Ali</creatorcontrib><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>MEDLINE - Academic</collection><collection>OSTI.GOV</collection><jtitle>Medical physics (Lancaster)</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Paul, Narinder S.</au><au>Blobel, Joerg</au><au>Kashani, Hany</au><au>Rice, Murray</au><au>Ursani, Ali</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Quantification of arterial plaque and lumen density with MDCT</atitle><jtitle>Medical physics (Lancaster)</jtitle><addtitle>Med Phys</addtitle><date>2010-08</date><risdate>2010</risdate><volume>37</volume><issue>8</issue><spage>4227</spage><epage>4237</epage><pages>4227-4237</pages><issn>0094-2405</issn><eissn>2473-4209</eissn><coden>MPHYA6</coden><abstract>Purpose:
This study aimed to derive a mathematical correction function in order to normalize the CT number measurements for small volume arterial plaque and small vessel mimicking objects, imaged with multidetector CT (MDCT).
Methods:
A commercially available calcium plaque phantom (QRM GmbH, Moehrendorf, Germany) and a custom built cardiovascular phantom were scanned with 320 and 64 MDCT scanners. The calcium hydroxyapatite plaque phantom contained objects 0.5–5.0 mm in diameter with known CT attenuation nominal values ranging 50–800 HU. The cardiovascular phantom contained vessel mimicking objects 1.0–5.0 mm in diameter with different contrast media. Both phantoms were scanned using clinical protocols for CT angiography and images were reconstructed with different filter kernels. The measured CT number (HU) and diameter of each object were analyzed on three clinical postprocessing workstations. From the resultant data, a mathematical formula was derived based on absorption function
exp
(
−
μ
∗
d
)
to demonstrate the relation between measured CT numbers and object diameters.
Results:
The percentage reduction in measured CT number (HU) for the group of selected filter kernels, apparent during CT angiography, is dependent only on the object size (plaque or vessel diameter). The derived formula of the form
1
−
c
∗
exp
(
−
a
∗
d
^
b
)
showed reduction in CT number for objects between 0.5 and 5 mm in diameter, with asymptote reaching background noise for small objects with diameters nearing the CT in-plane resolution (0.35 mm). No reduction was observed for the objects with diameters equal or larger than 5 mm.
Conclusions:
A clear mathematical relationship exists between object diameter and reduction in measured CT number in HU. This function is independent of exposure parameters and inherent attenuation properties of the objects studied. Future developments include the incorporation of this mathematical model function into quantification software in order to automatically generate a true assessment of measured CT number (HU) corresponding to plaque physical density
ρ
(
g
/
cm
3
)
. This is a significant development for the accurate, noninvasive classification of noncalcified arterial plaque.</abstract><cop>United States</cop><pub>American Association of Physicists in Medicine</pub><pmid>20879583</pmid><doi>10.1118/1.3447725</doi><tpages>11</tpages></addata></record> |
| fulltext | fulltext |
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| ispartof | Medical physics (Lancaster), 2010-08, Vol.37 (8), p.4227-4237 |
| issn | 0094-2405 2473-4209 |
| language | eng |
| recordid | cdi_osti_scitechconnect_22096753 |
| source | MEDLINE; Wiley Online Library All Journals; Alma/SFX Local Collection |
| subjects | Absorptiometry, Photon - instrumentation Absorptiometry, Photon - methods ABSORPTION Angiography APATITES arterial plaque Arteries - physiopathology Atherosclerosis - diagnostic imaging Atherosclerosis - physiopathology BACKGROUND NOISE BIOMEDICAL RADIOGRAPHY blood vessels Calcium calcium compounds CALCIUM PHOSPHATES Calibration cardiovascular system CLASSIFICATION Computed tomography COMPUTER CODES Computer Simulation Computer software computerised tomography COMPUTERIZED TOMOGRAPHY CONTRAST MEDIA CORONARIES CT coronary angiography diagnostic radiography Humans image reconstruction KERNELS medical image processing Medical image reconstruction Medical imaging Models, Cardiovascular Numerical modeling PHANTOMS Phantoms, Imaging Radiographic Image Interpretation, Computer-Assisted - methods Radiography RADIOLOGY AND NUCLEAR MEDICINE Reconstruction Tomography, X-Ray Computed - instrumentation Tomography, X-Ray Computed - methods Vacuum tubes Vascular system X‐ray imaging |
| title | Quantification of arterial plaque and lumen density with MDCT |
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