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Experimental study on bioluminescence tomography with multimodality fusion.

Lv Y, Tian J, Cong W, Wang G - Int J Biomed Imaging (2007)

Bottom Line: To verify the influence of a priori information on the nonuniqueness problem of bioluminescence tomography (BLT), the multimodality imaging fusion based BLT experiment is performed by multiview noncontact detection mode, which incorporates the anatomical information obtained by the microCT scanner and the background optical properties based on diffuse reflectance measurements.In the reconstruction procedure, the utilization of adaptive finite element methods (FEMs) and a priori permissible source region refines the reconstructed results and improves numerical robustness and efficiency.The comparison between the absence and employment of a priori information shows that multimodality imaging fusion is essential to quantitative BLT reconstruction.

View Article: PubMed Central - PubMed

Affiliation: Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, P.O. Box 2728, Beijing 100080, China.

ABSTRACT
To verify the influence of a priori information on the nonuniqueness problem of bioluminescence tomography (BLT), the multimodality imaging fusion based BLT experiment is performed by multiview noncontact detection mode, which incorporates the anatomical information obtained by the microCT scanner and the background optical properties based on diffuse reflectance measurements. In the reconstruction procedure, the utilization of adaptive finite element methods (FEMs) and a priori permissible source region refines the reconstructed results and improves numerical robustness and efficiency. The comparison between the absence and employment of a priori information shows that multimodality imaging fusion is essential to quantitative BLT reconstruction.

No MeSH data available.


Related in: MedlinePlus

The initial homogeneous (a) and heterogeneous (b) finite element meshes used inthe BLT reconstruction. The black areas represent a priori permissible source regions.
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fig2: The initial homogeneous (a) and heterogeneous (b) finite element meshes used inthe BLT reconstruction. The black areas represent a priori permissible source regions.

Mentions: When the BLT reconstruction is performed, the physical phantom is an anatomical andoptical homogeneous object if two types of a priori information are not considered.Area-weighted method is employed to approximate the homogeneous optical property.Through the difference of detected surface light power distribution in four views,as demonstrated in Figure 3 [8], we may infer the permissible source region as , as shown in Figure 4(a). During the reconstruction procedure, a modified Newton method with active-set strategy is employed for the minimization problem ateach level. Using a posteriori error estimation techniques, the elements with higher errorsand reconstructed values in the forbidden and permissible source regions, respectively,are selected for adaptive mesh refinement after the reconstruction is accomplished onthe coarse mesh. Red-green refinement strategy reasonably implements the local meshrefinement. Note that BLT with a coarsely discretized mesh means less unknownvariables, higher computational efficiency, and better numerical stability than that witha finely discretized counterpart. Hence, the optimization of the objective function isindispensable on the coarse mesh. The detailed explanation and discussion can be found elsewhere[9]. After four mesh refinements, Figure 5(a) shows the final reconstructed results. Due to the absence of anatomical and optical information, the BLT reconstruction cannot distinguish two light sources, and the reconstructed position is also far from the actual one despite that the roughly inferred permissible source region is utilized. When the anatomical information is considered, the selection of permissible source region may be restricted in the left lung, asillustrated in Figure 4(b). Two light sources can be distinguished from the reconstructed results, as shown in Figure 5(b). Although there are small relative errors in source density between the reconstructed and actual sources, the preferable source localization cannot be obtained. Finally, Figure 5(c) displays the reconstructed results in terms of the utilization of anatomical and optical information. The position and density of light sources are better reconstructed. The quantitative comparison above is summarized in Table 2, which further demonstrates the importance of anatomical and optical information for BLT reconstruction.


Experimental study on bioluminescence tomography with multimodality fusion.

Lv Y, Tian J, Cong W, Wang G - Int J Biomed Imaging (2007)

The initial homogeneous (a) and heterogeneous (b) finite element meshes used inthe BLT reconstruction. The black areas represent a priori permissible source regions.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2211423&req=5

fig2: The initial homogeneous (a) and heterogeneous (b) finite element meshes used inthe BLT reconstruction. The black areas represent a priori permissible source regions.
Mentions: When the BLT reconstruction is performed, the physical phantom is an anatomical andoptical homogeneous object if two types of a priori information are not considered.Area-weighted method is employed to approximate the homogeneous optical property.Through the difference of detected surface light power distribution in four views,as demonstrated in Figure 3 [8], we may infer the permissible source region as , as shown in Figure 4(a). During the reconstruction procedure, a modified Newton method with active-set strategy is employed for the minimization problem ateach level. Using a posteriori error estimation techniques, the elements with higher errorsand reconstructed values in the forbidden and permissible source regions, respectively,are selected for adaptive mesh refinement after the reconstruction is accomplished onthe coarse mesh. Red-green refinement strategy reasonably implements the local meshrefinement. Note that BLT with a coarsely discretized mesh means less unknownvariables, higher computational efficiency, and better numerical stability than that witha finely discretized counterpart. Hence, the optimization of the objective function isindispensable on the coarse mesh. The detailed explanation and discussion can be found elsewhere[9]. After four mesh refinements, Figure 5(a) shows the final reconstructed results. Due to the absence of anatomical and optical information, the BLT reconstruction cannot distinguish two light sources, and the reconstructed position is also far from the actual one despite that the roughly inferred permissible source region is utilized. When the anatomical information is considered, the selection of permissible source region may be restricted in the left lung, asillustrated in Figure 4(b). Two light sources can be distinguished from the reconstructed results, as shown in Figure 5(b). Although there are small relative errors in source density between the reconstructed and actual sources, the preferable source localization cannot be obtained. Finally, Figure 5(c) displays the reconstructed results in terms of the utilization of anatomical and optical information. The position and density of light sources are better reconstructed. The quantitative comparison above is summarized in Table 2, which further demonstrates the importance of anatomical and optical information for BLT reconstruction.

Bottom Line: To verify the influence of a priori information on the nonuniqueness problem of bioluminescence tomography (BLT), the multimodality imaging fusion based BLT experiment is performed by multiview noncontact detection mode, which incorporates the anatomical information obtained by the microCT scanner and the background optical properties based on diffuse reflectance measurements.In the reconstruction procedure, the utilization of adaptive finite element methods (FEMs) and a priori permissible source region refines the reconstructed results and improves numerical robustness and efficiency.The comparison between the absence and employment of a priori information shows that multimodality imaging fusion is essential to quantitative BLT reconstruction.

View Article: PubMed Central - PubMed

Affiliation: Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, P.O. Box 2728, Beijing 100080, China.

ABSTRACT
To verify the influence of a priori information on the nonuniqueness problem of bioluminescence tomography (BLT), the multimodality imaging fusion based BLT experiment is performed by multiview noncontact detection mode, which incorporates the anatomical information obtained by the microCT scanner and the background optical properties based on diffuse reflectance measurements. In the reconstruction procedure, the utilization of adaptive finite element methods (FEMs) and a priori permissible source region refines the reconstructed results and improves numerical robustness and efficiency. The comparison between the absence and employment of a priori information shows that multimodality imaging fusion is essential to quantitative BLT reconstruction.

No MeSH data available.


Related in: MedlinePlus