Comparison of two detector systems for cone beam CT small animal imaging: a preliminary study

Purpose: To compare two detector systems - one based on the charge-coupled device (CCD) and image amplifier, the other based on a-Si/CsI flat panel, for cone beam computed-tomography (CT) imaging of small animals. A high resolution, high framing rate detector system for the cone beam CT imaging of small animals was developed. The system consists of a 2048×3072×12 bit CCD optically coupled to an image amplifier and an x-ray phosphor screen. The CCD has an intrinsic pixel size of 12 μm but the effective pixel size can be adjusted through the magnification adjustment of the optical coupling systems. The system is used in conjunction with an x-ray source and a rotating stage for holding and rotating the scanned object in the cone beam CT imaging experiments. The advantages of the system include but are not limited to the ability to adjust the effective pixel size and to achieve extremely high spatial resolution and temporal resolution. However, the need to use optical coupling compromises the detective quanta efficiency (DQE) of the system. In this paper, the imaging characteristics of the system were presented and compared with those of an a- Si/CsI flat-panel detector system.

[1]  Srinivasan Vedantham,et al.  Solid-state fluoroscopic imager for high-resolution angiography: parallel-cascaded linear systems analysis. , 2004, Medical physics.

[2]  R. Street,et al.  A comparison of x-ray detectors for mouse CT imaging , 2004, Physics in medicine and biology.

[3]  J P Felmlee,et al.  An evaluation of the signal and noise characteristics of four CCD-based film digitizers. , 1998, Medical physics.

[4]  L L Fajardo,et al.  Lens distortion in optically coupled digital x-ray imaging. , 2000, Medical physics.

[5]  D. P. Trauernicht,et al.  System considerations in CCD-based x-ray imaging for digital chest radiography and digital mammography. , 1997, Medical physics.

[6]  D P Fyhrie,et al.  A cone beam computed tomography system for true 3D imaging of specimens. , 1997, Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine.

[7]  S Suryanarayanan,et al.  Mammographic imaging with a small format CCD-based digital cassette: physical characteristics of a clinical system. , 2000, Medical physics.

[8]  J A Rowlands,et al.  X-ray detectors for digital radiography. , 1997, Physics in medicine and biology.

[9]  G Wang,et al.  Design of a dual CCD configuration to improve the signal-to-noise ratio. , 2000, Medical physics.

[10]  Stephen Rudin,et al.  Micro-angiographic detector with fluoroscopic capability , 2002, SPIE Medical Imaging.

[11]  Patrik Sund,et al.  Evaluation of the imaging properties of two generations of a CCD-based system for digital chest radiography. , 2002, Medical physics.

[12]  Jie Yang,et al.  High-resolution Micro-CT evaluation of mid- to long-term effects of estrogen deficiency on rat trabecular bone. , 2003, Academic radiology.

[13]  Kerry T. Krugh,et al.  Microcalcification detectability for four mammographic detectors: flat-panel, CCD, CR, and screen/film). , 2002, Medical physics.

[14]  Johnathon R. Walls,et al.  Correction of artefacts in optical projection tomography , 2005, Physics in medicine and biology.

[15]  A Workman,et al.  A comparison of the imaging properties of CCD-based devices used for small field digital mammography. , 2002, Physics in medicine and biology.

[16]  Elsa Arribas,et al.  Visibility of simulated microcalcifications--a hardcopy-based comparison of three mammographic systems. , 2005, Medical physics.

[17]  Xinming Liu,et al.  A-Si:H/CsI(Tl) flat-panel versus computed radiography for chest imaging applications: image quality metrics measurement. , 2004, Medical physics.

[18]  Sol M. Grunera.  Charge-coupled device area x-ray detectors , 2002 .

[19]  Sandor L. Barna,et al.  Calibration procedures for charge-coupled device x-ray detectors , 1999 .

[20]  Harrison H Barrett,et al.  Task-based lens design with application to digital mammography. , 2005, Journal of the Optical Society of America. A, Optics, image science, and vision.

[21]  G. Iinuma,et al.  Diagnosis of gastric cancers: comparison of conventional radiography and digital radiography with a 4 million-pixel charge-coupled device. , 2000, Radiology.

[22]  M B Williams,et al.  Analysis of the detective quantum efficiency of a developmental detector for digital mammography. , 1999, Medical Physics (Lancaster).