Method to improve cancerous lesion detection sensitivity in a dedicated dual-head scintimammography system

Abstract

An improved method for enhancing the contrast between background and lesion areas of a breast undergoing dual-head scintimammographic examination comprising: 1) acquiring a pair of digital images from a pair of small FOV or mini gamma cameras compressing the breast under examination from opposing sides; 2) inverting one of the pair of images to align or co-register with the other of the images to obtain co-registered pixel values; 3) normalizing the pair of images pixel-by-pixel by dividing pixel values from each of the two acquired images and the co-registered image by the average count per pixel in the entire breast area of the corresponding detector; and 4) multiplying the number of counts in each pixel by the value obtained in step 3 to produce a normalization enhanced two dimensional contrast map. This enhanced (increased contrast) contrast map enhances the visibility of minor local increases (uptakes) of activity over the background and therefore improves lesion detection sensitivity, especially of small lesions.

Description

[0001]The United States of America may have certain rights to this invention under Management and Operating Contract No. DE-AC05-84ER 40150 from the Department of Energy.FIELD OF THE INVENTION[0002]The present invention relates to dual-head scintimammography techniques for the detection and localization of cancerous lesions particularly in breast examinations and more particularly to a method for combining the information provided by the opposing heads in a dual head system to maximize system sensitivity for cancerous lesions.BACKGROUND OF THE INVENTION[0003]Currently scintimammography imaging to detect breast cancer is performed with standard nuclear medicine cameras and it suffers from poor sensitivity for lesions under about 1 cm in diameter and lesions located in the medial aspect of the breast, away from the large camera surface. The main contributing factor to this poor performance is the poor spatial resolution during imaging due to the relatively large distance between the l...

AI Technical Summary

Benefits of technology

[0009]According to the present invention, there is provided an improved method for enhancing the contrast between background and lesion areas of a breast undergoing dual-head scintimammographic examination comprising: 1) acquiring a pair of digital images from a pair of small FOV or mini gamma cameras compressing the breast under examination from opposing sides; 2) inverting one of the pair of images to align or co-register with the other of the images to obtain co-registered pixel values; 3) normalizing the pair of images pixel-by-pixel by dividing pixel values from each of the two acquired images and the co-registered image by the average count per pixel in the entire breast area of the corresponding detector; and 4) multiplying the number of counts in each pixel by the value obtained in step 3 to produce a normalization enhanced two dimensional contrast map. This enhanced (increased contrast) contrast map enhances the visibility of minor local increases (uptakes) of activity over the background and therefore improves lesion detection sensitivity, especially of small lesions. It also increases lesion sensitivity independently of lesion position within the breast volume.

Problems solved by technology

Currently scintimammography imaging to detect breast cancer is performed with standard nuclear medicine cameras and it suffers from poor sensitivity for lesions under about 1 cm in diameter and lesions located in the medial aspect of the breast, away from the large camera surface.

The main contributing factor to this poor performance is the poor spatial resolution during imaging due to the relatively large distance between the lesion and the collimator of the detector head.

While this improved approach confirmed that the dual head system is especially useful in most clinical situations where lesion location is not known a priori, the remaining important issue was how to combine most efficiently the two images obtained from the double sided imaging.

This technique further enhanced lesion vs. background contrast, but still did not produced the degree of contrast desired.

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