Feasibility of volume-of-interest (VOI) scanning technique in cone beam breast CT-a preliminary study

Chen, Lingyun; Shaw, Chris C.; Altunbaş, M.; Lai, Chao Jen; Liu, Xinming; Han, Tao; Wang, Tianpeng; Yang, Wei Tse; Whitman, Gary J.

doi:10.1118/1.2948397

Cited by 43 publications

(47 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These are referred to as interior tomography reconstruction algorithms. Alternatively, the peripheral regions of the patient cross section can be irradiated with greatly reduced dose levels, avoiding the severe truncation of the projection data (65,66). Reconstructed images have decreased quality outside the VOI but full image quality within the VOI (Fig 6).…”

Section: Voi Imaging and Interior Tomographymentioning

confidence: 99%

Achieving Routine Submillisievert CT Scanning: Report from the Summit on Management of Radiation Dose in CT

McCollough¹,

Chen²,

Kalender³

et al. 2012

Radiology

249

160

View full text Add to dashboard Cite

Section: Voi Imaging and Interior Tomographymentioning

confidence: 99%

Achieving Routine Submillisievert CT Scanning: Report from the Summit on Management of Radiation Dose in CT

McCollough¹,

Chen²,

Kalender³

et al. 2012

Radiology

249

160

View full text Add to dashboard Cite

“…As discussed in the previous paper, 18 image reconstruction for the VOI still requires the use of projection data outside the VOI. To pad the truncated space outside the VOI, low resolution and low dose CBCT data maybe reprojected to provide projection data with same pixel size as high resolution CCD detector.…”

Section: Introductionmentioning

confidence: 99%

“…To solve this problem, we previously proposed a VOI CBCT technique. 18 With this technique, it is possible to selectively image a VOI with high image quality, reduced scatter effect, and lowered radiation dose both inside and outside the VOI. However, the detectability of the small MCs inside the VOI would still be limited by the spatial resolution of the FP detector.…”

Section: Introductionmentioning

confidence: 99%

Dual resolution cone beam breast CT: A feasibility study

et al. 2009

Self Cite

View full text Add to dashboard Cite

Purpose: In this study, the authors investigated the feasibility of a dual resolution volume-ofinterest ͑VOI͒ cone beam breast CT technique and compared two implementation approaches in terms of dose saving and scatter reduction. Methods: With this technique, a lead VOI mask with an opening is inserted between the x-ray source and the breast to deliver x-ray exposure to the VOI while blocking x rays outside the VOI. A CCD detector is used to collect the high resolution projection data of the VOI. Low resolution cone beam CT ͑CBCT͒ images of the entire breast, acquired with a flat panel ͑FP͒ detector, were used to calculate the projection data outside the VOI with the ray-tracing reprojection method. The Feldkamp-Davis-Kress filtered backprojection algorithm was used to reconstruct the dual resolution 3D images. Breast phantoms with 180 m and smaller microcalcifications ͑MCs͒ were imaged with both FP and FP-CCD dual resolution CBCT systems, respectively. Two approaches of implementing the dual resolution technique, breast-centered approach and VOI-centered approach, were investigated and evaluated for dose saving and scatter reduction with Monte Carlo simulation using a GEANT4 package. Results:The results showed that the breast-centered approach saved more breast absorbed dose than did VOI-centered approach with similar scatter reduction. The MCs in fatty breast phantom, which were invisible with FP CBCT scan, became visible with the FP-CCD dual resolution CBCT scan. Conclusions:These results indicate potential improvement of the image quality inside the VOI with reduced breast dose both inside and outside the VOI.

show abstract

“…Chityala et al, 12 Chen et al, 13 and Schafer et al 14 proposed a different method that irradiates parts of the scan FOV at a lower dose. In this case, a nonuniform VOI beam filter is applied to reduce dose outside the VOI.…”

Section: Introductionmentioning

confidence: 99%

Patient‐bounded extrapolation using low‐dose priors for volume‐of‐interest imaging in C‐arm CT

et al. 2015

View full text Add to dashboard Cite

Purpose: Three-dimensional (3D) volume-of-interest (VOI) imaging with C-arm systems provides anatomical information in a predefined 3D target region at a considerably low x-ray dose. However, VOI imaging involves laterally truncated projections from which conventional reconstruction algorithms generally yield images with severe truncation artifacts. Heuristic based extrapolation methods, e.g., water cylinder extrapolation, typically rely on techniques that complete the truncated data by means of a continuity assumption and thus appear to be ad-hoc. It is our goal to improve the image quality of VOI imaging by exploiting existing patient-specific prior information in the workflow. Methods: A necessary initial step prior to a 3D acquisition is to isocenter the patient with respect to the target to be scanned. To this end, low-dose fluoroscopic x-ray acquisitions are usually applied from anterior-posterior (AP) and medio-lateral (ML) views. Based on this, the patient is isocentered by repositioning the table. In this work, we present a patient-bounded extrapolation method that makes use of these noncollimated fluoroscopic images to improve image quality in 3D VOI reconstruction. The algorithm first extracts the 2D patient contours from the noncollimated AP and ML fluoroscopic images. These 2D contours are then combined to estimate a volumetric model of the patient. Forward-projecting the shape of the model at the eventually acquired C-arm rotation views gives the patient boundary information in the projection domain. In this manner, we are in the position to substantially improve image quality by enforcing the extrapolated line profiles to end at the known patient boundaries, derived from the 3D shape model estimate. Results: The proposed method was evaluated on eight clinical datasets with different degrees of truncation. The proposed algorithm achieved a relative root mean square error (rRMSE) of about 1.0% with respect to the reference reconstruction on nontruncated data, even in the presence of severe truncation, compared to a rRMSE of 8.0% when applying a state-of-the-art heuristic extrapolation technique. Conclusions: The method we proposed in this paper leads to a major improvement in image quality for 3D C-arm based VOI imaging. It involves no additional radiation when using fluoroscopic images that are acquired during the patient isocentering process. The model estimation can be readily integrated into the existing interventional workflow without additional hardware. C 2015 American Association of Physicists in Medicine. [http://dx

show abstract

Feasibility of volume-of-interest (VOI) scanning technique in cone beam breast CT-a preliminary study

Cited by 43 publications

References 31 publications

Achieving Routine Submillisievert CT Scanning: Report from the Summit on Management of Radiation Dose in CT

Achieving Routine Submillisievert CT Scanning: Report from the Summit on Management of Radiation Dose in CT

Dual resolution cone beam breast CT: A feasibility study

Patient‐bounded extrapolation using low‐dose priors for volume‐of‐interest imaging in C‐arm CT

Contact Info

Product

Resources

About