Achieving super-resolution X-ray imaging with mobile C-arm devices.
BACKGROUND
The term super-resolution refers to the process of combining a set of low-resolution images into a high-resolution image using image processing methods. This work is concerned with the reconstruction of high-resolution X-ray images. Specifically, we address the problem of acquiring X-ray images from multiple, very close view points.


METHODS
We propose to use a novel experimental robotic C-arm device to create high-resolution X-ray images. For this purpose, we suggest different strategies for acquiring multiple low-resolution images, and we provide the steps to achieve acquisition-error compensation. Compared to visible light images, X-ray images have the particularity that parallax effects render super-resolution very difficult. Using the acquired multi-frame data, we evaluate recent well-known super-resolution reconstruction algorithms. The same algorithms are evaluated based on synthetic 3D phantom data and real X-ray images.


RESULTS
In experiments with both synthetic and real projection data, we successfully reconstruct up to four times higher-resolution images. These images reveal structures and details which are not perceivable in the low-resolution images.


CONCLUSIONS
The advantage of super-resolution techniques for X-ray is the potential reduction of radiation dose for patients and medical personnel. Potential medical applications include the diagnosis of early-stage osteoporosis and the detection of very small calcifications.
Bodensteiner
C
C
Institute of Robotics and Cognitive Systems, University of Lübeck, Germany. bodensteiner@rob.uni-luebeck.de
Darolti
C
C
Schweikard
A
A
D000465:Algorithms; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D012371:Robotics / Q000295:instrumentation* / Q000379:methods*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*