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.

1. 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 pair of images to obtain a co-registered image and co-registered pixel values; 
 3) normalizing the pair of images pixel-by-pixel by dividing the 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 of the breast. 
 
     
     
       2. The method of  claim 1  wherein the breast is directly compressed by the opposing mini gamma cameras. 
     
     
       3. A method for imaging a breast, comprising:
 generating first and second digital images using a pair of opposing small field of view or mini gamma cameras of a dual-head scintimammographic imaging system while compressing the breast under examination from opposing sides;   processing the first and second images to produce first and second processed images having adjusted pixel values, the processing including:
 (a) for each of the first and second images, adjusting the pixel values in the image based on a value derived from that image, and 
 (b) registering one of the first and second images to the other of the first and second images; and 
   generating a combined image derived from corresponding pixel values from the first and second processed images.    
     
     
       4. The method of claim 3, wherein the step of adjusting comprises:
 adjusting the pixel values of first image on a pixel-by-pixel based on a value derived from the pixels of the first image; and   adjusting the pixel values of the second image on a pixel-by-pixel based on a value derived from the pixels of the second image.    
     
     
       5. The method of claim 3, wherein the step of adjusting comprises:
 normalizing the pixels values of the first image on a pixel-by-pixel basis based on a value derived from the pixels of the first image; and   normalizing the pixels values of the second image on a pixel-by-pixel basis based on a value derived from the pixels of the second image.    
     
     
       6. The method of claim 3, wherein the step of adjusting comprises:
 normalizing the pixel values of the first image on a pixel-by-pixel basis by dividing the pixel values from the first image by the average count per pixel in the entire breast area of the first image; and   normalizing pixels values of the second image on a pixel-by-pixel basis by dividing the pixel values from the second image by the average count per pixel in the entire breast area of the second image.    
     
     
       7. The method of claim 3, wherein the step of generating the combined image comprises combining corresponding pixel values of the first and second processed images on a pixel-by-pixel basis.  
     
     
       8. A method for imaging a breast, comprising:
 generating first and second digital images using a pair of opposing small field of view or mini gamma cameras of a dual-head scintimammographic imaging system while compressing the breast under examination from opposing sides;   processing the first and second images to produce co-registered first and second processed images having adjusted pixel values, the processing including separately altering the pixel values of each of the first and second images; and   generating a combined image derived from corresponding pixel values from the first and second processed images.    
     
     
       9. The method of claim 8, wherein the step of processing includes registering one of the first and second images to the other of the first and second images.  
     
     
       10. The method of claim 8, wherein the step of separately altering comprises:
 changing the pixel values of the first image on a pixel-by-pixel basis based on a value derived from the pixels of the first image; and   changing the pixel values of the second image on a pixel-by-pixel basis based on a value derived from the pixels of the second image.    
     
     
       11. The method of claim 8, wherein the step of processing includes normalizing the pixel values in each of the first and second images.  
     
     
       12. The method of claim 8, wherein the step of generating the combined image comprises combining corresponding pixel values of the first and second processed images on a pixel-by-pixel basis.  
     
     
       13. A method for imaging a breast, comprising:
 generating first and second digital images using a pair of opposing small field of view or mini gamma cameras of a dual-head scintimammographic imaging system while compressing the breast under examination from opposing sides;   processing the first and second images to produce co-registered first and second processed images, wherein the processing includes calculating, for each pixel of the first and second image, a corresponding value, the corresponding value being calculated from a pixel value of the pixel to which the corresponding value corresponds; and   generating a combined image derived from corresponding pixel values from the first and second processed images.    
     
     
       14. A dual-head scintimammographic system for imaging a breast, comprising:
 first and second small field of view or mini gamma cameras, the first and second cameras disposed opposite each other for generating first and second images of the breast while compressing the breast under examination; and   a computer for processing the first and second images to produce first and second processed images having adjusted pixel values and for generating a combined image derived from corresponding pixel values from the first and second processed images,   wherein the processing includes:
 (a) for each of the pair of images, adjusting the pixel values in the image based on a value derived from that image, and 
 (b) registering one of the first and second images to the other of the first and second images.  
   
     
     
       15. The dual-head scintimammographic system of claim 14, wherein the adjusting comprises:
 adjusting the pixel values of the first image on a pixel-by-pixel basis based on a value derived from the pixels of the first image; and   adjusting the pixel values of the second image on a pixel-by-pixel basis based on a value derived from the pixels of the second image.    
     
     
       16. The dual-head scintimammographic system of claim 14, wherein the adjusting comprises:
 normalizing the pixel values of the first image on a pixel-by-pixel basis based on a value derived from the pixels of the first image; and   normalizing the pixel values of the second image on a pixel-by-pixel basis based on a value derived from the pixels of the second image.    
     
     
       17. The dual-head scintimammographic system of claim 14, wherein the adjusting comprises:
 normalizing the pixel values of the first image on a pixel-by-pixel basis by dividing the pixel values from the first image by the average count per pixel in the entire breast area of the first image; and   normalizing the pixel values of the second image on a pixel-by-pixel basis by dividing the pixel values from the second image by the average count per pixel in the entire breast area of the second image.    
     
     
       18. The dual-head scintimammographic system of claim 14, wherein generating the combined image comprises combining corresponding pixel values of the first and second processed images on a pixel-by-pixel basis.  
     
     
       19. A dual-head scintimammographic system for imaging a breast, comprising:
 first and second small field of view or mini gamma cameras, the first and second cameras disposed opposite each other for generating first and second images of the breast while compressing the breast under examination; and   a computer for processing the first and second images to produce co-registered first and second processed images having adjusted pixel values and for generating a combined image derived from corresponding pixel values from the first and second processed images,   wherein the processing includes separately altering the pixel values of each of the first and second images.    
     
     
       20. The dual-head scintimammographic system of claim 19, wherein the processing includes registering one of the first and second images to the other of the first and second images.  
     
     
       21. The dual-head scintimammographic system of claim 19, wherein the separately altering comprises:
 changing the pixel values of the first image on a pixel-by-pixel basis based on a value derived from the pixels of the first image; and   changing the pixel values of the second image on a pixel-by-pixel basis based on a value derived from the pixels of the second image.    
     
     
       22. The dual-head scintimammographic system of claim 19, wherein the processing includes normalizing the pixel values in each of the first and second images.  
     
     
       23. The dual-head scintimammographic system of claim 19, wherein generating the combined image comprises combining corresponding pixel values of the first and second processed images on a pixel-by-pixel basis.  
     
     
       24. A dual-head scintimammographic system for imaging a breast, comprising:
 first and second small field of view or mini gamma cameras, the first and second cameras disposed opposite each other for generating first and second images of the breast while compressing the breast under examination; and   a computer for processing the first and second images to produce co-registered first and second processed images and for generating a combined image derived from corresponding pixel values from the first and second processed images,   wherein the processing includes wherein calculating, for each pixel of the first and second image, a corresponding value, the corresponding value being calculated from a pixel value of the pixel to which the corresponding value corresponds.