The Effects of Region of Interest, Differentiation Methods and Rebinning Sizes on the Modulation Transfer Function of a Mammography Systems

Abstract

In this study, the image quality of the mammography system was measured by mathematical methods. New methods for performance measurements have been used to quantitatively evaluate the image quality in mammography systems. Since the quantitative evaluation of imaging quality gives more objective results than evaluation of visual, numerical evaluations have been emphasized within the scope of the study. The Slanted-edge method was used for the calculation of modulation transfer function (MTF), and angular calculations were made in the use of this method. On effect of different region-of-interest (ROI) selection on edge spread function (ESF), use of different differentiation methods for line spread function (LSF), MTF, and on the effect of different rebinning sizes on ESF, LSF and MTF were investigated. All these methods consist of the calculation were designed to perform using the MATLAB program.

Keywords

• Mammography systems,Image quality evaluation,Modulation transfer function,Matlab

Mamografi Sistemlerinde İlgi Alanı, Türev ve İnce Gruplama Seçimlerinin Modülasyon Transfer Fonksiyonunun Üzerine Etkileri

Abstract

Bu çalışmada, mamografi sisteminin görüntü kalitesi matematiksel yöntemler ile ölçülmüştür. Mamografi sistemlerinde performans ölçümleri için uygulanan yeni yöntemler, bu sistemlerin görüntü kalitesinin sayısal olarak değerlendirilmesinde kullanılmıştır. Görüntüleme kalitesinin sayısal değerlendirilmesi, görsel değerlendirmelere göre daha objektif sonuçlar verdiğinden çalışma kapsamında sayısal değerlendirmeler üzerinde durulmuştur. Modülasyon transfer fonksiyonu (MTF) hesaplanmasında kenar görüntüleme metodu kullanılmış ve bu metodun kullanımında açı hesaplamaları yapılmıştır. Farklı ilgi alan seçimlerinde (ROI) kenar dağılım fonksiyonlarının (ESF) nasıl değiştiği gözlemlenmiş, farklı türev seçimlerinin çizgisel dağılım fonksiyonu (LSF) ve MTF üzerine etkisi ve ince gruplama (rebinning) işleminin ESF, LSF, MTF üzerine etkileri incelenmiştir. Bütün bu yöntemlerin hesaplamaları, MATLAB programı kullanılarak tasarlanıp gerçekleştirilmiştir.

Keywords

• Mamografi sistemleri,Görüntü kaltesi değerlendirme,modülasyon transfer fonksiyonu,Matlab

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