放射線診斷原理與技術學題庫下載題庫

[解釋] Recent reports have emphasizednthe potential for dual-energy computedradiographic applications. Annimproved method for single-exposurematerial-selective imaging withna photostimulable phosphor computedradiography system wasninvestigated. The essential elements of thetechnique are (a)nprefiltration with gadolinium, which divides the incidentbroad-beamnx-ray spectrum into low-energy and high-energy peaks; (b) acassettenconsisting of four photostimulable phosphor plates that recordimagesnof increasing mean energies, with a computed energy separation of 23keVnfrom the front to the rear plat...

[解釋] Recent reports have emphasizednthe potential for dual-energy computedradiographic applications. Annimproved method for single-exposurematerial-selective imaging withna photostimulable phosphor computedradiography system wasninvestigated. The essential elements of thetechnique are (a)nprefiltration with gadolinium, which divides the incidentbroad-beamnx-ray spectrum into low-energy and high-energy peaks; (b) acassettenconsisting of four photostimulable phosphor plates that recordimagesnof increasing mean energies, with a computed energy separation of 23keVnfrom the front to the rear plate; (c) spatially dependent scatter andbeam-hardeningncorrections; and (d) a noise-reduction algorithm based onnoisencorrelations between bone- selective and soft-tissue-selectivedual-energynimages. These elements result in improved material cancellationandnsignal-to-noise ratio throughout the image.

[出處]http://radiology.rsnajnls.org/cgi/content/abstract/174/1/243n