Kilovoltage cone-beam CT: Comparative dose and image quality evaluations in partial and full-angle scan protocols
Purpose: To assess imaging dose of partial and full-angle kilovoltage CBCT scan protocols and to evaluate image quality for each protocol. Methods: The authors obtained the CT dose index (CTDI) of the kilovoltage CBCT protocols in an on-board imager by ion chamber (IC) measurements and Monte Carlo (...
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| creator | Kim, Sangroh Yoo, Sua Yin, Fang-Fang Samei, Ehsan Yoshizumi, Terry |
| description | Purpose:
To assess imaging dose of partial and full-angle kilovoltage CBCT scan protocols and to evaluate image quality for each protocol.
Methods:
The authors obtained the CT dose index (CTDI) of the kilovoltage CBCT protocols in an on-board imager by ion chamber (IC) measurements and Monte Carlo (MC) simulations. A total of six new CBCT scan protocols were evaluated: Standard-dose head (100 kVp, 151 mA s, partial-angle), low-dose head (100 kVp, 75 mA s, partial-angle), high-quality head (100 kVp, 754 mA s, partial-angle), pelvis (125 kVp, 706 mA s, full-angle), pelvis spotlight (125 kVp, 752 mA s, partial-angle), and low-dose thorax (110 kVp, 271 mA s, full-angle). Using the point dose method, various CTDI values were calculated by (1) the conventional weighted CTDI
(
CTDI
w
)
calculation and (2) Bakalyar’s method
(
CTDI
wb
)
. The MC simulations were performed to obtain the
CTDI
w
and
CTDI
wb
, as well as from (3) central slice averaging
(
CTDI
2
D
)
and (4) volume averaging
(
CTDI
3
D
)
techniques. The CTDI values of the new protocols were compared to those of the old protocols (full-angle CBCT protocols). Image quality of the new protocols was evaluated following the CBCT image quality assurance (QA) protocol [S. Yoo
et al.
, “A quality assurance program for the on-board imager®,” Med. Phys.
33(11), 4431–4447 (2006)] testing Hounsfield unit (HU) linearity, spatial linearity/resolution, contrast resolution, and HU uniformity.
Results:
The
CTDI
w
were found as 6.0, 3.2, 29.0, 25.4, 23.8, and 7.7 mGy for the new protocols, respectively. The
CTDI
w
and
CTDI
wb
differed within
+
3
%
between IC measurements and MC simulations. Method (2) results were within ±12% of method (1). In MC simulations, the
CTDI
w
and
CTDI
wb
were comparable to the
CTDI
2
D
and
CTDI
3
D
with the differences ranging from −4.3% to 20.6%. The
CTDI
3
D
were smallest among all the CTDI values.
CTDI
w
of the new protocols were found as
∼
14
times lower for standard head scan and 1.8 times lower for standard body scan than the old protocols, respectively. In the image quality QA tests, all the protocols except low-dose head and low-dose thorax protocols were within the tolerance in the HU verification test. The HU value for the two protocols was always higher than the nominal value. All the protocols passed the spatial linearity/resolution and HU uniformity tests. In the contrast resolution test, only high-quality head and pelvis scan protocols were within the tolerance. In addition, cres |
| doi_str_mv | 10.1118/1.3438478 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_scita</sourceid><recordid>TN_cdi_scitation_primary_10_1118_1_3438478</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>754001925</sourcerecordid><originalsourceid>FETCH-LOGICAL-c5418-f6a651efb2a59882a45c46fdf1d845bed92c210440bc6985f9ea9f18d697ec5c3</originalsourceid><addsrcrecordid>eNqN0U9vFCEYBnBiNHZbPfgFDIkHU5OpwMAM9GBiNv6LNXqoZ8IwLxXDDLsDs2a_vWxnNb3UeOLAjycv74PQM0ouKKXyNb2oeS15Kx-gFeNtXXFG1EO0IkTxinEiTtBpSj8JIU0tyGN0woisKWnZCm0_-xB3MWRzA9jGEaoOzIDX15d4HYeNmUz2O8B9TIDN2GM_HOB2NsHnPYadCXMRcUzYj7jw7E24hW4OoTLjTQCcrCl3U8zRxpCeoEfOhARPj-cZ-v7-3fX6Y3X19cOn9durygpOZeUa0wgKrmNGKCmZ4cLyxvWO9pKLDnrFLKOEc9LZRknhFBjlqOwb1YIVtj5DL5bcmLLXyfoM9kf54Qg2a1YW1LSMFvVyUWW-7Qwp68EnCyGYEeKcdCs4IVQxUeT5Iu0UU5rA6c1UtjHtNSX6UIOm-lhDsc-PqXM3QP9X_tl7AdUCfvkA-_uT9Jdvx8A3iz_843bh97-506g-NKpLoyXg1X8H_Avv4nRnuk3v6t8EZMHL</addsrcrecordid><sourcetype>Open Access Repository</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>754001925</pqid></control><display><type>article</type><title>Kilovoltage cone-beam CT: Comparative dose and image quality evaluations in partial and full-angle scan protocols</title><source>MEDLINE</source><source>Wiley Online Library Journals Frontfile Complete</source><source>Alma/SFX Local Collection</source><creator>Kim, Sangroh ; Yoo, Sua ; Yin, Fang-Fang ; Samei, Ehsan ; Yoshizumi, Terry</creator><creatorcontrib>Kim, Sangroh ; Yoo, Sua ; Yin, Fang-Fang ; Samei, Ehsan ; Yoshizumi, Terry</creatorcontrib><description>Purpose:
To assess imaging dose of partial and full-angle kilovoltage CBCT scan protocols and to evaluate image quality for each protocol.
Methods:
The authors obtained the CT dose index (CTDI) of the kilovoltage CBCT protocols in an on-board imager by ion chamber (IC) measurements and Monte Carlo (MC) simulations. A total of six new CBCT scan protocols were evaluated: Standard-dose head (100 kVp, 151 mA s, partial-angle), low-dose head (100 kVp, 75 mA s, partial-angle), high-quality head (100 kVp, 754 mA s, partial-angle), pelvis (125 kVp, 706 mA s, full-angle), pelvis spotlight (125 kVp, 752 mA s, partial-angle), and low-dose thorax (110 kVp, 271 mA s, full-angle). Using the point dose method, various CTDI values were calculated by (1) the conventional weighted CTDI
(
CTDI
w
)
calculation and (2) Bakalyar’s method
(
CTDI
wb
)
. The MC simulations were performed to obtain the
CTDI
w
and
CTDI
wb
, as well as from (3) central slice averaging
(
CTDI
2
D
)
and (4) volume averaging
(
CTDI
3
D
)
techniques. The CTDI values of the new protocols were compared to those of the old protocols (full-angle CBCT protocols). Image quality of the new protocols was evaluated following the CBCT image quality assurance (QA) protocol [S. Yoo
et al.
, “A quality assurance program for the on-board imager®,” Med. Phys.
33(11), 4431–4447 (2006)] testing Hounsfield unit (HU) linearity, spatial linearity/resolution, contrast resolution, and HU uniformity.
Results:
The
CTDI
w
were found as 6.0, 3.2, 29.0, 25.4, 23.8, and 7.7 mGy for the new protocols, respectively. The
CTDI
w
and
CTDI
wb
differed within
+
3
%
between IC measurements and MC simulations. Method (2) results were within ±12% of method (1). In MC simulations, the
CTDI
w
and
CTDI
wb
were comparable to the
CTDI
2
D
and
CTDI
3
D
with the differences ranging from −4.3% to 20.6%. The
CTDI
3
D
were smallest among all the CTDI values.
CTDI
w
of the new protocols were found as
∼
14
times lower for standard head scan and 1.8 times lower for standard body scan than the old protocols, respectively. In the image quality QA tests, all the protocols except low-dose head and low-dose thorax protocols were within the tolerance in the HU verification test. The HU value for the two protocols was always higher than the nominal value. All the protocols passed the spatial linearity/resolution and HU uniformity tests. In the contrast resolution test, only high-quality head and pelvis scan protocols were within the tolerance. In addition, crescent effect was found in the partial-angle scan protocols.
Conclusions:
The authors found that
CTDI
w
of the new CBCT protocols has been significantly reduced compared to the old protocols with acceptable image quality. The
CTDI
w
values in the point dose method were close to the volume averaging method within 9%–21% for all the CBCT scan protocols. The Bakalyar’s method produced more accurate dose estimation within 14%. The HU inaccuracy from low-dose head and low-dose thorax protocols can render incorrect dose results in the treatment planning system. When high soft-tissue contrast data are desired, high-quality head or pelvis scan protocol is recommended depending on the imaging area. The point dose method can be applicable to estimate CBCT dose with reasonable accuracy in the clinical environment.</description><identifier>ISSN: 0094-2405</identifier><identifier>EISSN: 2473-4209</identifier><identifier>DOI: 10.1118/1.3438478</identifier><identifier>PMID: 20831072</identifier><identifier>CODEN: MPHYA6</identifier><language>eng</language><publisher>United States: American Association of Physicists in Medicine</publisher><subject>60 APPLIED LIFE SCIENCES ; ACCURACY ; BEAMrnc ; CHEST ; Computed tomography ; computerised tomography ; COMPUTERIZED TOMOGRAPHY ; Cone beam computed tomography ; Cone-Beam Computed Tomography - methods ; cone-beam CT ; CTDI ; DOSIMETRY ; Dosimetry/exposure assessment ; EVALUATION ; HEAD ; image resolution ; IONIZATION CHAMBERS ; Linear Models ; Medical image contrast ; Medical image quality ; Medical imaging ; Medical X‐ray imaging ; Monte Carlo ; MONTE CARLO METHOD ; Monte Carlo methods ; Monte Carlo simulations ; partial-angle scan ; PELVIS ; Phantoms, Imaging ; PLANNING ; point dose method ; QUALITY ASSURANCE ; Quality Control ; Radiation Dosage ; RADIATION DOSES ; RADIATION PROTECTION AND DOSIMETRY ; Radiation treatment ; RESOLUTION ; SIMULATION ; Spatial resolution ; TESTING ; VERIFICATION</subject><ispartof>Medical physics (Lancaster), 2010-07, Vol.37 (7), p.3648-3659</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-c5418-f6a651efb2a59882a45c46fdf1d845bed92c210440bc6985f9ea9f18d697ec5c3</citedby><cites>FETCH-LOGICAL-c5418-f6a651efb2a59882a45c46fdf1d845bed92c210440bc6985f9ea9f18d697ec5c3</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%2F1.3438478$$EPDF$$P50$$Gwiley$$H</linktopdf><linktohtml>$$Uhttps://onlinelibrary.wiley.com/doi/full/10.1118%2F1.3438478$$EHTML$$P50$$Gwiley$$H</linktohtml><link.rule.ids>230,314,776,780,881,1411,27901,27902,45550,45551</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/20831072$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink><backlink>$$Uhttps://www.osti.gov/biblio/22096721$$D View this record in Osti.gov$$Hfree_for_read</backlink></links><search><creatorcontrib>Kim, Sangroh</creatorcontrib><creatorcontrib>Yoo, Sua</creatorcontrib><creatorcontrib>Yin, Fang-Fang</creatorcontrib><creatorcontrib>Samei, Ehsan</creatorcontrib><creatorcontrib>Yoshizumi, Terry</creatorcontrib><title>Kilovoltage cone-beam CT: Comparative dose and image quality evaluations in partial and full-angle scan protocols</title><title>Medical physics (Lancaster)</title><addtitle>Med Phys</addtitle><description>Purpose:
To assess imaging dose of partial and full-angle kilovoltage CBCT scan protocols and to evaluate image quality for each protocol.
Methods:
The authors obtained the CT dose index (CTDI) of the kilovoltage CBCT protocols in an on-board imager by ion chamber (IC) measurements and Monte Carlo (MC) simulations. A total of six new CBCT scan protocols were evaluated: Standard-dose head (100 kVp, 151 mA s, partial-angle), low-dose head (100 kVp, 75 mA s, partial-angle), high-quality head (100 kVp, 754 mA s, partial-angle), pelvis (125 kVp, 706 mA s, full-angle), pelvis spotlight (125 kVp, 752 mA s, partial-angle), and low-dose thorax (110 kVp, 271 mA s, full-angle). Using the point dose method, various CTDI values were calculated by (1) the conventional weighted CTDI
(
CTDI
w
)
calculation and (2) Bakalyar’s method
(
CTDI
wb
)
. The MC simulations were performed to obtain the
CTDI
w
and
CTDI
wb
, as well as from (3) central slice averaging
(
CTDI
2
D
)
and (4) volume averaging
(
CTDI
3
D
)
techniques. The CTDI values of the new protocols were compared to those of the old protocols (full-angle CBCT protocols). Image quality of the new protocols was evaluated following the CBCT image quality assurance (QA) protocol [S. Yoo
et al.
, “A quality assurance program for the on-board imager®,” Med. Phys.
33(11), 4431–4447 (2006)] testing Hounsfield unit (HU) linearity, spatial linearity/resolution, contrast resolution, and HU uniformity.
Results:
The
CTDI
w
were found as 6.0, 3.2, 29.0, 25.4, 23.8, and 7.7 mGy for the new protocols, respectively. The
CTDI
w
and
CTDI
wb
differed within
+
3
%
between IC measurements and MC simulations. Method (2) results were within ±12% of method (1). In MC simulations, the
CTDI
w
and
CTDI
wb
were comparable to the
CTDI
2
D
and
CTDI
3
D
with the differences ranging from −4.3% to 20.6%. The
CTDI
3
D
were smallest among all the CTDI values.
CTDI
w
of the new protocols were found as
∼
14
times lower for standard head scan and 1.8 times lower for standard body scan than the old protocols, respectively. In the image quality QA tests, all the protocols except low-dose head and low-dose thorax protocols were within the tolerance in the HU verification test. The HU value for the two protocols was always higher than the nominal value. All the protocols passed the spatial linearity/resolution and HU uniformity tests. In the contrast resolution test, only high-quality head and pelvis scan protocols were within the tolerance. In addition, crescent effect was found in the partial-angle scan protocols.
Conclusions:
The authors found that
CTDI
w
of the new CBCT protocols has been significantly reduced compared to the old protocols with acceptable image quality. The
CTDI
w
values in the point dose method were close to the volume averaging method within 9%–21% for all the CBCT scan protocols. The Bakalyar’s method produced more accurate dose estimation within 14%. The HU inaccuracy from low-dose head and low-dose thorax protocols can render incorrect dose results in the treatment planning system. When high soft-tissue contrast data are desired, high-quality head or pelvis scan protocol is recommended depending on the imaging area. The point dose method can be applicable to estimate CBCT dose with reasonable accuracy in the clinical environment.</description><subject>60 APPLIED LIFE SCIENCES</subject><subject>ACCURACY</subject><subject>BEAMrnc</subject><subject>CHEST</subject><subject>Computed tomography</subject><subject>computerised tomography</subject><subject>COMPUTERIZED TOMOGRAPHY</subject><subject>Cone beam computed tomography</subject><subject>Cone-Beam Computed Tomography - methods</subject><subject>cone-beam CT</subject><subject>CTDI</subject><subject>DOSIMETRY</subject><subject>Dosimetry/exposure assessment</subject><subject>EVALUATION</subject><subject>HEAD</subject><subject>image resolution</subject><subject>IONIZATION CHAMBERS</subject><subject>Linear Models</subject><subject>Medical image contrast</subject><subject>Medical image quality</subject><subject>Medical imaging</subject><subject>Medical X‐ray imaging</subject><subject>Monte Carlo</subject><subject>MONTE CARLO METHOD</subject><subject>Monte Carlo methods</subject><subject>Monte Carlo simulations</subject><subject>partial-angle scan</subject><subject>PELVIS</subject><subject>Phantoms, Imaging</subject><subject>PLANNING</subject><subject>point dose method</subject><subject>QUALITY ASSURANCE</subject><subject>Quality Control</subject><subject>Radiation Dosage</subject><subject>RADIATION DOSES</subject><subject>RADIATION PROTECTION AND DOSIMETRY</subject><subject>Radiation treatment</subject><subject>RESOLUTION</subject><subject>SIMULATION</subject><subject>Spatial resolution</subject><subject>TESTING</subject><subject>VERIFICATION</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>eNqN0U9vFCEYBnBiNHZbPfgFDIkHU5OpwMAM9GBiNv6LNXqoZ8IwLxXDDLsDs2a_vWxnNb3UeOLAjycv74PQM0ouKKXyNb2oeS15Kx-gFeNtXXFG1EO0IkTxinEiTtBpSj8JIU0tyGN0woisKWnZCm0_-xB3MWRzA9jGEaoOzIDX15d4HYeNmUz2O8B9TIDN2GM_HOB2NsHnPYadCXMRcUzYj7jw7E24hW4OoTLjTQCcrCl3U8zRxpCeoEfOhARPj-cZ-v7-3fX6Y3X19cOn9durygpOZeUa0wgKrmNGKCmZ4cLyxvWO9pKLDnrFLKOEc9LZRknhFBjlqOwb1YIVtj5DL5bcmLLXyfoM9kf54Qg2a1YW1LSMFvVyUWW-7Qwp68EnCyGYEeKcdCs4IVQxUeT5Iu0UU5rA6c1UtjHtNSX6UIOm-lhDsc-PqXM3QP9X_tl7AdUCfvkA-_uT9Jdvx8A3iz_843bh97-506g-NKpLoyXg1X8H_Avv4nRnuk3v6t8EZMHL</recordid><startdate>201007</startdate><enddate>201007</enddate><creator>Kim, Sangroh</creator><creator>Yoo, Sua</creator><creator>Yin, Fang-Fang</creator><creator>Samei, Ehsan</creator><creator>Yoshizumi, Terry</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>201007</creationdate><title>Kilovoltage cone-beam CT: Comparative dose and image quality evaluations in partial and full-angle scan protocols</title><author>Kim, Sangroh ; Yoo, Sua ; Yin, Fang-Fang ; Samei, Ehsan ; Yoshizumi, Terry</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c5418-f6a651efb2a59882a45c46fdf1d845bed92c210440bc6985f9ea9f18d697ec5c3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2010</creationdate><topic>60 APPLIED LIFE SCIENCES</topic><topic>ACCURACY</topic><topic>BEAMrnc</topic><topic>CHEST</topic><topic>Computed tomography</topic><topic>computerised tomography</topic><topic>COMPUTERIZED TOMOGRAPHY</topic><topic>Cone beam computed tomography</topic><topic>Cone-Beam Computed Tomography - methods</topic><topic>cone-beam CT</topic><topic>CTDI</topic><topic>DOSIMETRY</topic><topic>Dosimetry/exposure assessment</topic><topic>EVALUATION</topic><topic>HEAD</topic><topic>image resolution</topic><topic>IONIZATION CHAMBERS</topic><topic>Linear Models</topic><topic>Medical image contrast</topic><topic>Medical image quality</topic><topic>Medical imaging</topic><topic>Medical X‐ray imaging</topic><topic>Monte Carlo</topic><topic>MONTE CARLO METHOD</topic><topic>Monte Carlo methods</topic><topic>Monte Carlo simulations</topic><topic>partial-angle scan</topic><topic>PELVIS</topic><topic>Phantoms, Imaging</topic><topic>PLANNING</topic><topic>point dose method</topic><topic>QUALITY ASSURANCE</topic><topic>Quality Control</topic><topic>Radiation Dosage</topic><topic>RADIATION DOSES</topic><topic>RADIATION PROTECTION AND DOSIMETRY</topic><topic>Radiation treatment</topic><topic>RESOLUTION</topic><topic>SIMULATION</topic><topic>Spatial resolution</topic><topic>TESTING</topic><topic>VERIFICATION</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Kim, Sangroh</creatorcontrib><creatorcontrib>Yoo, Sua</creatorcontrib><creatorcontrib>Yin, Fang-Fang</creatorcontrib><creatorcontrib>Samei, Ehsan</creatorcontrib><creatorcontrib>Yoshizumi, Terry</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>Kim, Sangroh</au><au>Yoo, Sua</au><au>Yin, Fang-Fang</au><au>Samei, Ehsan</au><au>Yoshizumi, Terry</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Kilovoltage cone-beam CT: Comparative dose and image quality evaluations in partial and full-angle scan protocols</atitle><jtitle>Medical physics (Lancaster)</jtitle><addtitle>Med Phys</addtitle><date>2010-07</date><risdate>2010</risdate><volume>37</volume><issue>7</issue><spage>3648</spage><epage>3659</epage><pages>3648-3659</pages><issn>0094-2405</issn><eissn>2473-4209</eissn><coden>MPHYA6</coden><abstract>Purpose:
To assess imaging dose of partial and full-angle kilovoltage CBCT scan protocols and to evaluate image quality for each protocol.
Methods:
The authors obtained the CT dose index (CTDI) of the kilovoltage CBCT protocols in an on-board imager by ion chamber (IC) measurements and Monte Carlo (MC) simulations. A total of six new CBCT scan protocols were evaluated: Standard-dose head (100 kVp, 151 mA s, partial-angle), low-dose head (100 kVp, 75 mA s, partial-angle), high-quality head (100 kVp, 754 mA s, partial-angle), pelvis (125 kVp, 706 mA s, full-angle), pelvis spotlight (125 kVp, 752 mA s, partial-angle), and low-dose thorax (110 kVp, 271 mA s, full-angle). Using the point dose method, various CTDI values were calculated by (1) the conventional weighted CTDI
(
CTDI
w
)
calculation and (2) Bakalyar’s method
(
CTDI
wb
)
. The MC simulations were performed to obtain the
CTDI
w
and
CTDI
wb
, as well as from (3) central slice averaging
(
CTDI
2
D
)
and (4) volume averaging
(
CTDI
3
D
)
techniques. The CTDI values of the new protocols were compared to those of the old protocols (full-angle CBCT protocols). Image quality of the new protocols was evaluated following the CBCT image quality assurance (QA) protocol [S. Yoo
et al.
, “A quality assurance program for the on-board imager®,” Med. Phys.
33(11), 4431–4447 (2006)] testing Hounsfield unit (HU) linearity, spatial linearity/resolution, contrast resolution, and HU uniformity.
Results:
The
CTDI
w
were found as 6.0, 3.2, 29.0, 25.4, 23.8, and 7.7 mGy for the new protocols, respectively. The
CTDI
w
and
CTDI
wb
differed within
+
3
%
between IC measurements and MC simulations. Method (2) results were within ±12% of method (1). In MC simulations, the
CTDI
w
and
CTDI
wb
were comparable to the
CTDI
2
D
and
CTDI
3
D
with the differences ranging from −4.3% to 20.6%. The
CTDI
3
D
were smallest among all the CTDI values.
CTDI
w
of the new protocols were found as
∼
14
times lower for standard head scan and 1.8 times lower for standard body scan than the old protocols, respectively. In the image quality QA tests, all the protocols except low-dose head and low-dose thorax protocols were within the tolerance in the HU verification test. The HU value for the two protocols was always higher than the nominal value. All the protocols passed the spatial linearity/resolution and HU uniformity tests. In the contrast resolution test, only high-quality head and pelvis scan protocols were within the tolerance. In addition, crescent effect was found in the partial-angle scan protocols.
Conclusions:
The authors found that
CTDI
w
of the new CBCT protocols has been significantly reduced compared to the old protocols with acceptable image quality. The
CTDI
w
values in the point dose method were close to the volume averaging method within 9%–21% for all the CBCT scan protocols. The Bakalyar’s method produced more accurate dose estimation within 14%. The HU inaccuracy from low-dose head and low-dose thorax protocols can render incorrect dose results in the treatment planning system. When high soft-tissue contrast data are desired, high-quality head or pelvis scan protocol is recommended depending on the imaging area. The point dose method can be applicable to estimate CBCT dose with reasonable accuracy in the clinical environment.</abstract><cop>United States</cop><pub>American Association of Physicists in Medicine</pub><pmid>20831072</pmid><doi>10.1118/1.3438478</doi><tpages>12</tpages></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0094-2405 |
| ispartof | Medical physics (Lancaster), 2010-07, Vol.37 (7), p.3648-3659 |
| issn | 0094-2405 2473-4209 |
| language | eng |
| recordid | cdi_scitation_primary_10_1118_1_3438478 |
| source | MEDLINE; Wiley Online Library Journals Frontfile Complete; Alma/SFX Local Collection |
| subjects | 60 APPLIED LIFE SCIENCES ACCURACY BEAMrnc CHEST Computed tomography computerised tomography COMPUTERIZED TOMOGRAPHY Cone beam computed tomography Cone-Beam Computed Tomography - methods cone-beam CT CTDI DOSIMETRY Dosimetry/exposure assessment EVALUATION HEAD image resolution IONIZATION CHAMBERS Linear Models Medical image contrast Medical image quality Medical imaging Medical X‐ray imaging Monte Carlo MONTE CARLO METHOD Monte Carlo methods Monte Carlo simulations partial-angle scan PELVIS Phantoms, Imaging PLANNING point dose method QUALITY ASSURANCE Quality Control Radiation Dosage RADIATION DOSES RADIATION PROTECTION AND DOSIMETRY Radiation treatment RESOLUTION SIMULATION Spatial resolution TESTING VERIFICATION |
| title | Kilovoltage cone-beam CT: Comparative dose and image quality evaluations in partial and full-angle scan protocols |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-08T13%3A04%3A11IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_scita&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Kilovoltage%20cone-beam%20CT:%20Comparative%20dose%20and%20image%20quality%20evaluations%20in%20partial%20and%20full-angle%20scan%20protocols&rft.jtitle=Medical%20physics%20(Lancaster)&rft.au=Kim,%20Sangroh&rft.date=2010-07&rft.volume=37&rft.issue=7&rft.spage=3648&rft.epage=3659&rft.pages=3648-3659&rft.issn=0094-2405&rft.eissn=2473-4209&rft.coden=MPHYA6&rft_id=info:doi/10.1118/1.3438478&rft_dat=%3Cproquest_scita%3E754001925%3C/proquest_scita%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=754001925&rft_id=info:pmid/20831072&rfr_iscdi=true |