Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy.
The purpose of this study is to investigate the optimal reference geometry for gamma camera calibration. Yet another question of interest was to assess the influence of the number of 3D Ordered Subsets Expectation Maximization (3D-OSEM) updates on activity quantification for SPECT imaging with 177Lu...
Saved in:
| Main Authors: | , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2017-01-01
|
| Series: | PLoS ONE |
| Online Access: | https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0182888&type=printable |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850229080389058560 |
|---|---|
| author | Emilio Mezzenga Vincenzo D'Errico Marco D'Arienzo Lidia Strigari Koutla Panagiota Federica Matteucci Stefano Severi Giovanni Paganelli Andrew Fenwick David Bianchini Francesco Marcocci Anna Sarnelli |
| author_facet | Emilio Mezzenga Vincenzo D'Errico Marco D'Arienzo Lidia Strigari Koutla Panagiota Federica Matteucci Stefano Severi Giovanni Paganelli Andrew Fenwick David Bianchini Francesco Marcocci Anna Sarnelli |
| author_sort | Emilio Mezzenga |
| collection | DOAJ |
| description | The purpose of this study is to investigate the optimal reference geometry for gamma camera calibration. Yet another question of interest was to assess the influence of the number of 3D Ordered Subsets Expectation Maximization (3D-OSEM) updates on activity quantification for SPECT imaging with 177Lu. The accuracy of 177Lu activity quantification was assessed both in small and in large objects. Two different reference geometries, namely a cylindrical homogeneous phantom and a Jaszczak 16 ml sphere surrounded by cold water, were used to determine the gamma camera calibration factor of a commercial SPECT/CT system. Moreover, the noise level and the concentration recovery coefficient were evaluated as a function of the number of 3D-OSEM updates by using the SPECT/CT images of the reference geometry phantoms and those of a cold Jaszczak phantom with three hot spheres (16ml, 8ml and 4ml), respectively. The optimal choice of the number of 3D-OSEM updates was based on a compromise between the noise level achievable in the reconstructed SPECT images and the concentration recovery coefficients. The quantitative accuracy achievable was finally validated on a test phantom, where a spherical insert composed of two concentric spheres was used to simulate a lesion in a warm background. Our data confirm and extend previous observations. Using the calibration factor obtained with the cylindrical homogeneous phantom and the Jaszczak 16 ml sphere, the recovered activity in the test phantom was underestimated by -16.4% and -24.8%, respectively. Our work has led us to conclude that gamma camera calibration performed with large homogeneous phantom outperforms calibration executed with the Jaszczak 16ml sphere. Furthermore, the results obtained support the assumption that approximately 50 OSEM updates represent a good trade-off to reach convergence in small volumes, meanwhile minimizing the noise level. |
| format | Article |
| id | doaj-art-ae68a6ae3fac48188f46bbb50c65af39 |
| institution | OA Journals |
| issn | 1932-6203 |
| language | English |
| publishDate | 2017-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj-art-ae68a6ae3fac48188f46bbb50c65af392025-08-20T02:04:20ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01128e018288810.1371/journal.pone.0182888Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy.Emilio MezzengaVincenzo D'ErricoMarco D'ArienzoLidia StrigariKoutla PanagiotaFederica MatteucciStefano SeveriGiovanni PaganelliAndrew FenwickDavid BianchiniFrancesco MarcocciAnna SarnelliThe purpose of this study is to investigate the optimal reference geometry for gamma camera calibration. Yet another question of interest was to assess the influence of the number of 3D Ordered Subsets Expectation Maximization (3D-OSEM) updates on activity quantification for SPECT imaging with 177Lu. The accuracy of 177Lu activity quantification was assessed both in small and in large objects. Two different reference geometries, namely a cylindrical homogeneous phantom and a Jaszczak 16 ml sphere surrounded by cold water, were used to determine the gamma camera calibration factor of a commercial SPECT/CT system. Moreover, the noise level and the concentration recovery coefficient were evaluated as a function of the number of 3D-OSEM updates by using the SPECT/CT images of the reference geometry phantoms and those of a cold Jaszczak phantom with three hot spheres (16ml, 8ml and 4ml), respectively. The optimal choice of the number of 3D-OSEM updates was based on a compromise between the noise level achievable in the reconstructed SPECT images and the concentration recovery coefficients. The quantitative accuracy achievable was finally validated on a test phantom, where a spherical insert composed of two concentric spheres was used to simulate a lesion in a warm background. Our data confirm and extend previous observations. Using the calibration factor obtained with the cylindrical homogeneous phantom and the Jaszczak 16 ml sphere, the recovered activity in the test phantom was underestimated by -16.4% and -24.8%, respectively. Our work has led us to conclude that gamma camera calibration performed with large homogeneous phantom outperforms calibration executed with the Jaszczak 16ml sphere. Furthermore, the results obtained support the assumption that approximately 50 OSEM updates represent a good trade-off to reach convergence in small volumes, meanwhile minimizing the noise level.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0182888&type=printable |
| spellingShingle | Emilio Mezzenga Vincenzo D'Errico Marco D'Arienzo Lidia Strigari Koutla Panagiota Federica Matteucci Stefano Severi Giovanni Paganelli Andrew Fenwick David Bianchini Francesco Marcocci Anna Sarnelli Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy. PLoS ONE |
| title | Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy. |
| title_full | Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy. |
| title_fullStr | Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy. |
| title_full_unstemmed | Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy. |
| title_short | Quantitative accuracy of 177Lu SPECT imaging for molecular radiotherapy. |
| title_sort | quantitative accuracy of 177lu spect imaging for molecular radiotherapy |
| url | https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0182888&type=printable |
| work_keys_str_mv | AT emiliomezzenga quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT vincenzoderrico quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT marcodarienzo quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT lidiastrigari quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT koutlapanagiota quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT federicamatteucci quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT stefanoseveri quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT giovannipaganelli quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT andrewfenwick quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT davidbianchini quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT francescomarcocci quantitativeaccuracyof177luspectimagingformolecularradiotherapy AT annasarnelli quantitativeaccuracyof177luspectimagingformolecularradiotherapy |