CT number changes within depth in CT and CBCT images
This study was carried out to determine the effect of increased depth to CT number on CT and CBCT images. In addition, this study was done to establish scanning method on CT and CBCT modalities in order to provide more precise dosimetry calculation involving CT and CBCT. An electron density phant...
| Päätekijä: | |
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| Aineistotyyppi: | Monograph |
| Kieli: | English |
| Julkaistu: |
Universiti Sains Malaysia
2015
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| Aiheet: | |
| Linkit: | http://eprints.usm.my/58259/1/SYARIFAH%20NURFAJRINA%20BINTI%20SYED%20JUNIT%20-%20e.pdf |
| _version_ | 1825907862536192000 |
|---|---|
| author | Junit, Syarifah Nurfajrina Syed |
| author_facet | Junit, Syarifah Nurfajrina Syed |
| author_sort | Junit, Syarifah Nurfajrina Syed |
| collection | USM |
| description | This study was carried out to determine the effect of increased depth to CT
number on CT and CBCT images. In addition, this study was done to establish
scanning method on CT and CBCT modalities in order to provide more precise
dosimetry calculation involving CT and CBCT. An electron density phantom with
tissue equivalent plugs was used in this study. The plug phantoms of various tissue
equivalent materials were placed at different depths between the centre and
peripheral of the phantom and scanned using CT and CBCT modalities. Images for
both modalities were acquired and CT numbers at different depth in the phantom
were analyzed. The results showed that on CT images, water equivalent plug
phantom showed highest changes of CT number from peripheral position to central
position with 146.4% and the lowest was air cavity with 0.55%. The results in CBCT
images showed that muscle tissue equivalent plug phantom gave the highest change
of CT number at increased depth with 6842.17% and the lowest difference was given
by dense bone tissue equivalent plug phantom with 11.72%. A comparison of
change in CT number between CT and CBCT showed that CBCT images having
higher rate of change of CT number from peripheral position to central position
compared to that in CT images. As conclusion, the CT number was found to be
significantly increase as the depth increased. Thus, dosimetry measurement using
CT number is suggested to be done at central position of phantom considering the
contribution of x-ray scattering to the point of measurement. A calibration of CT
number is required for dosimetry measurement at positions nearer to the surface of
medium. |
| first_indexed | 2024-03-06T16:10:25Z |
| format | Monograph |
| id | usm.eprints-58259 |
| institution | Universiti Sains Malaysia |
| language | English |
| last_indexed | 2024-03-06T16:10:25Z |
| publishDate | 2015 |
| publisher | Universiti Sains Malaysia |
| record_format | dspace |
| spelling | usm.eprints-582592023-05-07T00:16:29Z http://eprints.usm.my/58259/ CT number changes within depth in CT and CBCT images Junit, Syarifah Nurfajrina Syed RC71-78.7 Examination. Diagnosis Including raiography This study was carried out to determine the effect of increased depth to CT number on CT and CBCT images. In addition, this study was done to establish scanning method on CT and CBCT modalities in order to provide more precise dosimetry calculation involving CT and CBCT. An electron density phantom with tissue equivalent plugs was used in this study. The plug phantoms of various tissue equivalent materials were placed at different depths between the centre and peripheral of the phantom and scanned using CT and CBCT modalities. Images for both modalities were acquired and CT numbers at different depth in the phantom were analyzed. The results showed that on CT images, water equivalent plug phantom showed highest changes of CT number from peripheral position to central position with 146.4% and the lowest was air cavity with 0.55%. The results in CBCT images showed that muscle tissue equivalent plug phantom gave the highest change of CT number at increased depth with 6842.17% and the lowest difference was given by dense bone tissue equivalent plug phantom with 11.72%. A comparison of change in CT number between CT and CBCT showed that CBCT images having higher rate of change of CT number from peripheral position to central position compared to that in CT images. As conclusion, the CT number was found to be significantly increase as the depth increased. Thus, dosimetry measurement using CT number is suggested to be done at central position of phantom considering the contribution of x-ray scattering to the point of measurement. A calibration of CT number is required for dosimetry measurement at positions nearer to the surface of medium. Universiti Sains Malaysia 2015 Monograph NonPeerReviewed application/pdf en http://eprints.usm.my/58259/1/SYARIFAH%20NURFAJRINA%20BINTI%20SYED%20JUNIT%20-%20e.pdf Junit, Syarifah Nurfajrina Syed (2015) CT number changes within depth in CT and CBCT images. Project Report. Universiti Sains Malaysia. (Submitted) |
| spellingShingle | RC71-78.7 Examination. Diagnosis Including raiography Junit, Syarifah Nurfajrina Syed CT number changes within depth in CT and CBCT images |
| title | CT number changes within depth in CT and CBCT images |
| title_full | CT number changes within depth in CT and CBCT images |
| title_fullStr | CT number changes within depth in CT and CBCT images |
| title_full_unstemmed | CT number changes within depth in CT and CBCT images |
| title_short | CT number changes within depth in CT and CBCT images |
| title_sort | ct number changes within depth in ct and cbct images |
| topic | RC71-78.7 Examination. Diagnosis Including raiography |
| url | http://eprints.usm.my/58259/1/SYARIFAH%20NURFAJRINA%20BINTI%20SYED%20JUNIT%20-%20e.pdf |
| work_keys_str_mv | AT junitsyarifahnurfajrinasyed ctnumberchangeswithindepthinctandcbctimages |