| 1. |
- Dewyngaert, J. Keith, et al.
(författare)
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Procedure for unmasking localization information from ProstaScint scans for prostate radiation therapy treatment planning
- 2004
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Ingår i: International Journal of Radiation Oncology, Biology, Physics. - : Elsevier BV. - 0360-3016 .- 1879-355X. ; 60:2, s. 654-662
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To demonstrate a method to extract the meaningful biologic information from In-111-radiolabeled capromab pendetide (ProstaScint) SPECT scans for use in radiation therapy treatment planning by removing that component of the In-111 SPECT images associated with normal structures. Methods and Materials: We examined 20 of more than 80 patients who underwent simultaneous Tc-99m/In-111 SPECT scans, which were subsequently registered to the corresponding CT/MRI scans. A thresholding algorithm was used to identify Tc-99m uptake associated with blood vessels and CT electron density associated with bone marrow. Corresponding voxels were removed from the In-111 image set. Results: No single threshold value was found to be associated with the Tc-99m uptake that corresponded to the blood vessels. Intensity values were normalized to a global maximum and, as such, were dependent upon the quantity of Tc-99m pooled in the bladder. The reduced ProstaScint volume sets were segmented by use of a thresholding feature of the planning system and superimposed on the CT/MRI scans. Conclusions: ProstaScint images are now closer to becoming a biologically and therapeutically useful and accurate image set. After known sources of normal intensity are stripped away, the remaining areas that demonstrate uptake may be segmented and superimposed on the treatment-planning CT/MRI volume.
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| 2. |
- Lee, Benjamin Y., et al.
(författare)
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Unmasking true signal/tumor information from ProstaScint scans
- 2004
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Ingår i: MEDICAL IMAGING 2004: IMAGE PROCESSING, PTS 1-3. - : SPIE - International Society for Optical Engineering. - 0819452831 ; , s. 1980-1990
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Konferensbidrag (refereegranskat)abstract
- Purpose: Improve tumor localization in In-111 ProstaScint SPECT scans through improved reconstruction and identification/removal of non-specific blood pool volumes using simultaneously acquired Tc-99m tagged red blood cell (RBC) SPECT scans. Methods: We chose 30 patients with a history of prostate cancer who had undergone CT/MR and simultaneous Tc-99m RBC/In-111 ProstaScint SPECT scans due to rising PSA. To estimate the impact of reconstruction methods on anatomic definition and artifacts, SPECT volume data sets were reconstructed using ordered set-expectation maximization (OS-EM) with varying numbers of iterations and subsets, and these were compared against each other and against standard filtered back projection (FBP) reconstruction. Non-blood pool bladder activity in the Tc-99m scans was suppressed prior to subtraction from the In-111 scans by using an averaging algorithm within an ellipsoid volume encompassing the bladder. Outside the ellipsoid volume, Tc-99m voxel values were subtracted from the corresponding In-111 voxels after normalization of the data sets based on peak activity within the descending aorta. Results: OS-EM reconstruction using 3 iterations and 45 subsets showed improved representation of anatomy compared with FBP. Bladder suppression reduced artifacts in the prostate bed. The subtraction method reduced the blood pool signal, confirmed visually by superimposition with matched CT/MR scans. Conclusions: OS-EM reconstruction together with bladder suppression and subtraction of the blood pool may help improve the specificity of ProstaScint SPECT interpretation and increase its utility in radiation therapy treatment planning.
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| 3. |
- Noz, Marilyn E., et al.
(författare)
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Clinical applications from head to toe using a semiautomatic 3D inter/intramodality fusion technique
- 2003
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Ingår i: BIOMEDICAL IMAGE REGISTRATION. - 3540203435 ; , s. 387-397
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Konferensbidrag (refereegranskat)abstract
- Automated image registration techniques, particularly between modalities which clearly display anatomy and especially within the head, have become commonplace. Meanwhile advances in molecular imaging and the need to perform registration in other areas of body has driven the development of non-rigid and semiautomatic 3D volume fusion methods. This paper will focus on this latter class of 3D volume registration methods for a variety of clinical applications.
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| 4. |
- Noz, Marilyn E., et al.
(författare)
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Enhancing the utility of ProstaScint SPECT scans for patient management
- 2006
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Ingår i: Journal of medical systems. - : Springer-Verlag New York. - 0148-5598 .- 1573-689X. ; 30:2, s. 123-132
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Tidskriftsartikel (refereegranskat)abstract
- This project investigated reducing the artifact content of In-111 ProstaScint SPECT scans for use in treatment planning and management. Forty-one patients who had undergone CT or MRI scans and simultaneous Tc-99m RBC/In-111 ProstaScint SPECT scans were included. SPECT volume sets, reconstructed using Ordered Set-Expectation Maximum (OS-EM) were compared against those reconstructed with standard Filtered Back projection (FBP). Bladder activity in Tc-99m scans was suppressed within an ellipsoidal volume. Tc-99m voxel values were subtracted from the corresponding In-111 after scaling based on peak activity within the descending aorta. The SPECT volume data sets were merged with the CT or MRI scans before and after processing. Volume merging, based both on visual assessment and statistical evaluation, was not affected. Thus iterative reconstruction together with bladder suppression and blood pool subtraction may improve the interpretation and utility of ProstaScint SPECT scans for patient management.
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