Methods and system for shading a two-dimensional ultrasound image

Abstract

Various methods and systems are provided for shading a 2D ultrasound image, generated from ultrasound data, using a gradient determined from scalar values of the ultrasound image data. As one example, a method includes correlating image values of a dataset acquired with an ultrasound imaging system to height values; determining a gradient of the height values; applying shading to a 2D image generated from the dataset using the determined gradient; and displaying the shaded 2D image.

1 . A method, comprising:
 generating a flat, 2D image from a 2D dataset including scalar image values without height values, the 2D dataset acquired with an ultrasound imaging system;   determining a gradient of height values from the scalar image values;   applying shading to the flat, 2D image using the determined gradient; and   displaying the shaded flat, 2D image, having a 3D appearance, via a display screen of the ultrasound imaging system.   
     
     
         2 . The method of  claim 1 , wherein determining the gradient includes, for each pixel of the flat, 2D image generated from the 2D dataset including the scalar image values, converting a first scalar image value of the scalar image values included in the 2D dataset to a corresponding height value using a relationship between the first scalar image value and the height value. 
     
     
         3 . The method of  claim 2 , wherein the relationship is one of a linear relationship or a monotonic function. 
     
     
         4 . The method of  claim 2 , where the height value represents a height value of the first scalar image value but does not include height data. 
     
     
         5 . The method of  claim 1 , wherein determining the gradient of the height values includes determining a separate gradient for each height value of the height values, wherein each height value is associated with a corresponding pixel, and wherein the separate gradient for each height value is based on a difference between height values of pixels adjacent to the corresponding pixel within the flat, 2D image. 
     
     
         6 . The method of  claim 5 , wherein each separate gradient for each height value is used to compute a surface normal, and wherein applying shading to the flat, 2D image includes applying shading to the flat, 2D image using the surface normal of each corresponding pixel of the flat, 2D image. 
     
     
         7 . The method of  claim 1 , further comprising accessing the 2D dataset from a memory of the ultrasound imaging system. 
     
     
         8 . The method of  claim 1 , further comprising filtering the scalar image values prior to determining the gradient. 
     
     
         9 . The method of  claim 1 , wherein applying shading to the flat, 2D image using the determined gradient includes applying shading to the flat, 2D image based on a shading model which is a function of surface normals of the determined gradient, the shading model including one or more of a diffuse specular shading model, a Phong reflection model, a Blinn-Phong shading model, and a specular highlight shading model. 
     
     
         10 . The method of  claim 1 , wherein the 2D dataset is a B-mode dataset and the scalar image values include intensity values from the B-mode dataset. 
     
     
         11 . The method of  claim 1 , wherein the 2D dataset is a color Doppler dataset and the scalar image values are only a power component from the color Doppler dataset. 
     
     
         12 . The method of  claim 11 , wherein the color Doppler dataset further includes a velocity value for each pixel of the flat, 2D image, each velocity value converted to a color value, and wherein shading the flat, 2D image includes shading the color value of each pixel of the flat, 2D image using the determined gradient. 
     
     
         13 . An ultrasound imaging system, comprising:
 an ultrasound probe;   a display device; and   a processor communicatively connected to the ultrasound probe and the display device and including instructions stored in memory that, when executed during operation of the ultrasound imaging system, cause the processor to:
 access a 2D dataset, including only 2D scalar data and no 3D data, acquired with the ultrasound probe from the memory; 
 generate a flat, 2D image from the 2D dataset, where each pixel of the flat, 2D image includes a scalar, image value; 
 convert the scalar, image value of each pixel to a scalar, height value via a scalar valued function; 
 determine a gradient surface normal for each scalar, height value; 
 shade one or more pixels of the flat, 2D image using the gradient surface normal; and 
 display the shaded flat, 2D image via the display device. 
   
     
     
         14 . The ultrasound imaging system of  claim 13 , wherein determining the gradient surface normal for each scalar, height value includes, for a selected pixel, determining the gradient surface normal for the scalar, height value of the selected pixel using central differences and scalar, height values of pixels adjacent to the selected pixel. 
     
     
         15 . The ultrasound imaging system of  claim 13 , wherein the 2D dataset is a B-mode dataset and the scalar, image value of each pixel is an intensity value from the B-mode dataset. 
     
     
         16 . A method, comprising:
 generating a flat, 2D image from a 2D, B-mode dataset including scalar intensity values without height values, the 2D, B-mode dataset acquired with an ultrasound imaging system;   determining a gradient of height values from the scalar image values by, for each pixel of the flat, 2D image, converting a first scalar intensity value of the scalar intensity values included in the 2D, B-mode dataset to a corresponding height value using a relationship between the first scalar intensity value and the height value;   applying shading to the flat, 2D image using the determined gradient; and   displaying the shaded flat, 2D image, having a 3D appearance, via a display screen of the ultrasound imaging system.   
     
     
         17 . The method of  claim 16 , wherein the relationship is one of a linear relationship or a monotonic function. 
     
     
         18 . The method of  claim 16 , where the height value represents a height value of the first scalar intensity value but does not include height data. 
     
     
         19 . The method of  claim 16 , wherein determining the gradient of the height values includes determining a separate gradient for each height value of the height values, wherein each height value is associated with a corresponding pixel, and wherein the separate gradient for each height value is based on a difference between height values of pixels adjacent to the corresponding pixel within the flat, 2D image. 
     
     
         20 . The method of  claim 19 , wherein each separate gradient for each height value is used to compute a surface normal, and wherein applying shading to the flat, 2D image includes applying shading to the flat, 2D image using the surface normal of each corresponding pixel of the flat, 2D image.