PURPOSE: Model-based iterative reconstruction (MBIR) was recently shown to enable dose reduction in computed tomography (CT). The detectability of low-contrast lesions was assessed on CT images reconstructed with MBIR compared with the conventional filtered back-projection (FBP) method. MATERIALS AND METHODS: A phantom simulating brain gray matter containing small lesions mimicking early cerebral infarctions was scanned at tube currents of 50, 100, 200, and 400 mA. Images were reconstructed by use of both methods. Round regions were cropped from the reconstructed images, half with a lesion, the other half without. Eight radiologists reviewed the images and scored the certainty of lesion detection on a 5-point scale. Overall performance was analyzed by use of a receiver operating characteristic curve. RESULTS: For the tube currents investigated, the analysis showed that the mean areas under the curves for the reviewers were 0.65, 0.70, 0.82, and 0.83 for FBP and 0.70, 0.76, 0.78, and 0.90 for MBIR. For each current, there was no significant difference between the areas under the curves for the different reconstruction methods (p = 0.32, 0.24, 0.49, and 0.17). CONCLUSION: For the small, low-contrast lesions in the phantom model used in this study, no significant difference between detectability was observed for MBIR and FBP.
PURPOSE: Model-based iterative reconstruction (MBIR) was recently shown to enable dose reduction in computed tomography (CT). The detectability of low-contrast lesions was assessed on CT images reconstructed with MBIR compared with the conventional filtered back-projection (FBP) method. MATERIALS AND METHODS: A phantom simulating brain gray matter containing small lesions mimicking early cerebral infarctions was scanned at tube currents of 50, 100, 200, and 400 mA. Images were reconstructed by use of both methods. Round regions were cropped from the reconstructed images, half with a lesion, the other half without. Eight radiologists reviewed the images and scored the certainty of lesion detection on a 5-point scale. Overall performance was analyzed by use of a receiver operating characteristic curve. RESULTS: For the tube currents investigated, the analysis showed that the mean areas under the curves for the reviewers were 0.65, 0.70, 0.82, and 0.83 for FBP and 0.70, 0.76, 0.78, and 0.90 for MBIR. For each current, there was no significant difference between the areas under the curves for the different reconstruction methods (p = 0.32, 0.24, 0.49, and 0.17). CONCLUSION: For the small, low-contrast lesions in the phantom model used in this study, no significant difference between detectability was observed for MBIR and FBP.
Authors: A Korn; M Fenchel; B Bender; S Danz; T K Hauser; D Ketelsen; T Flohr; C D Claussen; M Heuschmid; U Ernemann; H Brodoefel Journal: AJNR Am J Neuroradiol Date: 2011-10-27 Impact factor: 3.825
Authors: Mark E Baker; Frank Dong; Andrew Primak; Nancy A Obuchowski; David Einstein; Namita Gandhi; Brian R Herts; Andrei Purysko; Erick Remer; Neil Vachhani; Neil Vachani Journal: AJR Am J Roentgenol Date: 2012-07 Impact factor: 3.959
Authors: Frédéric A Miéville; François Gudinchet; Francis Brunelle; François O Bochud; Francis R Verdun Journal: Phys Med Date: 2012-01-02 Impact factor: 2.685