Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Preprocessing of control portal images for patient setup verification during the treatments in external radiotherapy
Autore:
Hilt, G; Wolf, D; Aletti, P;
Indirizzi:
Inst Natl Polytech Lorraine, CNRS, UPRES A 7039, Ctr Rech Automat, F-54516Vandoeuvre Nancy, France Inst Natl Polytech Lorraine Vandoeuvre Nancy France F-54516 ancy, France Ctr Alexis Vautrin, Dept Radiotherapy, F-54511 Vandoeuvre Nancy, France Ctr Alexis Vautrin Vandoeuvre Nancy France F-54511 doeuvre Nancy, France
Titolo Testata:
MEDICAL PHYSICS
fascicolo: 12, volume: 26, anno: 1999,
pagine: 2539 - 2549
SICI:
0094-2405(199912)26:12<2539:POCPIF>2.0.ZU;2-V
Fonte:
ISI
Lingua:
ENG
Soggetto:
DIGITAL ENHANCEMENT; IMAGING DEVICE; EDGE-DETECTION; NOISE-ANALYSIS; RESTORATION; ALGORITHM; FILTERS; ROBUST; RESOLUTION; SIGNAL;
Keywords:
portal images; image preprocessing; noise reduction; image restoration; image segmentation;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Clinical Medicine
Life Sciences
Citazioni:
49
Recensione:
Indirizzi per estratti:
Indirizzo: Hilt, G Inst Natl Polytech Lorraine, CNRS, UPRES A 7039, Ctr Rech Automat,2 Ave Foret Haye, F-54516 Vandoeuvre Nancy, France Inst Natl Polytech Lorraine 2 Ave Foret Haye Vandoeuvre Nancy France F-54516
Citazione:
G. Hilt et al., "Preprocessing of control portal images for patient setup verification during the treatments in external radiotherapy", MED PHYS, 26(12), 1999, pp. 2539-2549

Abstract

The main problem in processing the control portal images is their poor quality. We have developed a way of improving the image quality to allow a segmentation stage. Three items were studied for this purpose the background gradient of intensity correction, the noise reduction, and the image restoration. The background was corrected by subtracting a smoothed version of theimage from the original. We tested 15 noise reduction methods. The most appropriate for control portal images was found to be the truncated average. Finally, four restoration techniques were compared. The maximum a posteriori (MAP) algorithm was the most efficient. The algorithms were tested over awide range of conditions (image quality). They produced a great improvement in anatomic detail for all the imaging systems, energies, and anatomical zones tested. For example, the signal-to-noise ratio of a SRI-100 pelvis image, acquired with 4 monitor units (MU) at 10 MV (very low quality image), increased from 0.97 to 42.84 after preprocessing. We found that the improvement in image quality facilitated or even enabled segmentation of the control portal images. The percentage of segments belonging to a structure increased from 30% to 65% in the example cited. The preprocessing of control portal images is the first step in checking the patient setup. (C) 1999 American Association of Physicists in Medicine. [S0094-2405(99)00912-8].

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 12/07/20 alle ore 06:47:34