A novel marker enhancement filter (MEF) for fluoroscopic images

17th International Conference on the Use of Computers in Radiation Therapy

物理学;计算机科学

Peshko, Olesya^1 ; Davidson, Timothy N.^1 ; Modersitzki, Jan^2 ; Terlaky, Tamás^3 ; Moseley, Douglas J^4

McMaster University, Hamilton, ON L8S 4K1, Canada^1

University of Lübeck, Lübeck, 23562, Germany^2

Lehigh University, Bethlehem, PA 18015, United States^3

Princess Margaret Hospital, Toronto, ON M5G 2M9, Canada^4

关键词: Automatic initialization;    Background suppression;    Contrast Enhancement;    Fluoroscopic images;    Fluoroscopic sequences;    Intensity variations;    Morphological operations;    Multiple orientations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/489/1/012038/pdf
DOI  :  10.1088/1742-6596/489/1/012038

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

To enhance the measurements of radio-opaque cylindrical fiducial markers in low contrast x-ray and fluoroscopic images, a novel nonlinear marker enhancement filter (MEF) has been designed. It was primarily developed to assist in automatic initialization of a tracking procedure for intra-fraction organ motion analysis in fluoroscopic sequences. Conventional procedures were not able to provide sufficient improvement due to the complications of noise, small marker size, cylindrical shape and multiple orientations, intensity variations of the background, and the presence of overlaying anatomical measurements in this application. The proposed MEF design is based on the principles of linear scale space. It includes measures that assess the probability of each pixel to belong to a marker measurement, morphological operations, and a novel contrast enhancement function for standardization of the filter output. The MEF was tested on fluoroscopic images of two phantoms and three prostate patients, and was shown to perform better or comparable to the existing filters in terms of marker enhancement and background suppression, while performing significantly better in marker shape preservation.