Technique for real-time rendering of medical images using virtual spherical light sources

Patent metadata

Field	Value
Publication number	US-12475633-B2
Application number	US-202318296387-A
Country	US
Kind code	B2
Filing date	Apr 6, 2023
Priority date	May 6, 2022
Publication date	Nov 18, 2025
Grant date	Nov 18, 2025

Abstract

For real-time rendering of medical images from volumetric data obtained from a medical scanner, one or more optical properties of the received volumetric data are determined. A light volume associated to a spherical light source is constructed. The light volume comprises a series of consecutive spherical slices through which light propagates while determining a fraction of the light propagating from one spherical slice to a neighboring spherical slice depending on the optical properties. The constructed light volume is sampling with a gradient-free shading that depends on the determined optical properties. At least one medical image is rendered in relation to the received volumetric data based on the sampled light volume.

First claim

The invention claimed is:

1 . A computer-implemented method for real-time rendering of medical images from volumetric data obtained from a medical scanner, the method comprising:
receiving volumetric data from the medical scanner; determining at least one optical property in relation to the received volumetric data; constructing, prior to rendering a medical image, a light volume in its entirety associated to a spherical light source, wherein the light volume comprises a grid of voxels representing a series of consecutive spherical slices through which light from the spherical light source propagates according to a consecutive order, wherein the light volume stores values for an amount of light that reaches each voxel in the grid of voxels, wherein constructing the light volume comprises determining a fraction of the light propagating from a spherical slice of the series of consecutive spherical slices to a corresponding neighboring spherical slice of the series of consecutive spherical slices according to the consecutive order, and wherein the propagating of the light depends on the determined at least one optical property in relation to the received volumetric data associated with the spherical slice; and rendering, in real time, the medical image in relation to the received volumetric data from a view point that is apart from the spherical light source, wherein rendering is based on sampling the constructed light volume, wherein the sampling comprises a gradient-free shading that depends on the determined at least one optical property in relation to the received volumetric data associated with the spherical slice.

2 . The computer-implemented method of claim 1 , wherein the medical scanner comprises a device from the group of: an ultrasound device; a positron emission tomography device; a computed tomography device; and a magnetic resonance tomography device.

3 . The computer-implemented method of claim 1 , wherein rendering comprises rendering the medical image using a device from the group of: a screen; a stereoscopic display; a virtual reality display; and an augmented reality headset.

4 . The computer-implemented method of claim 1 , wherein the received volumetric data are acquired, by the medical scanner, at a predetermined size of a time-step, and wherein constructing the light volume is performed for each time-step.

5 . The computer-implemented method of claim 1 , wherein the received volumetric data are acquired, by the medical scanner, at a predetermined size of a time-step, and wherein constructing the light volume comprises, at one time-step, re-generating the light volume from a previous time-step.

6 . The computer-implemented method of claim 1 , wherein constructing the light volume comprises transforming from polar to Cartesian coordinates, and wherein sampling the constructed light volume comprises inversely transforming from Cartesian to polar coordinates.

7 . The computer-implemented method of claim 1 , wherein sampling the light volume comprises applying a two-dimensional and/or three-dimensional reconstruction filter.

8 . The computer-implemented method of claim 7 , wherein the reconstruction filter comprises a Gaussian kernel.

9 . The computer-implemented method of claim 1 , wherein the spherical light source is non-static and/or wherein at least one property of the spherical light source varies over time, wherein the at least one property of the spherical light source comprises a position, a size, a color, and/or an intensity.

10 . The computer-implemented method of claim 1 , wherein the received volumetric data are non-static and/or vary over time.

11 . The computer-implemented method of claim 1 , wherein the determined at least one optical property is associated to at least one structure comprised in the volumetric data, and wherein the at least one optical property is selected from the group of: an opacity; a reflectance; a color; and at least one value indicative of a chromatic scattering.

12 . The computer-implemented method of claim 1 , wherein the series of consecutive spherical slices is ordered radially outward and/or wherein the spherical light source comprises a point-like light source.

13 . The computer-implemented method of claim 1 , wherein constructing and/or sampling the light volume is performed by a graphics processing unit.

14 . A system for real-time rendering of medical images from volumetric data obtained from a medical scanner, the system comprising:
a first interface configured for receiving volumetric data from the medical scanner; a first processor configured for determining at least one optical property in relation to the received volumetric data; a second processor configured for constructing a light volume associated to a spherical light source, wherein the light volume comprises a grid of voxels representing a series of consecutive spherical slices through which light from the spherical light source propagates according to a consecutive order, wherein constructing the light volume comprises determining a fraction of the light propagating from a spherical slice of the series of consecutive spherical slices to a corresponding neighboring spherical slice of the series of consecutive spherical slices according to the consecutive order, wherein the light volume stores a value for an amount of light that reaches each voxel in the grid of voxels and wherein the propagating of the light depends on the determined at least one optical property in relation to the received volumetric data associated with the spherical slice; a third processor configured for rendering a medical image in relation to the received volumetric data from a view point that is apart from the spherical light source, wherein rendering is based on sampling the constructed light volume, wherein the sampling comprises a gradient-free shading that depends on the determined at least one optical property in relation to the received volumetric data associated with the spherical slice; and a second interface configured for outputting the medical image.

15 . The system of claim 14 , wherein the medical scanner comprises an ultrasound device, a positron emission tomography device, a computed tomography device, or a magnetic resonance tomography device; wherein the second interface outputs to a screen, a stereoscopic display, a virtual reality display, or an augmented reality headset; and wherein the second and/or third processor comprises a graphics processing unit.

16 . The system of claim 14 , wherein the first interface is configured to receive the volumetric data at a predetermined size of a time-step, and wherein the second processor is configured to construct the light volume for each time-step or, at one time-step, re-generate the light volume from a previous time-step.

17 . The system of claim 14 wherein the second processor is configured to construct the light volume as a transformation from polar to Cartesian coordinates, and wherein the third processor is configured to sample the constructed light volume by inversely transformation from the Cartesian coordinates to the polar coordinates.

18 . The system of claim 14 , wherein the received volumetric data are non-static and/or vary over time, wherein the spherical light source is non-static and/or wherein at least one property of the spherical light source varies over time, the at least one property of the spherical light source comprising a position, a size, a color, and/or an intensity.

19 . The system of claim 14 , wherein the determined at

Assignees

• Siemens Healthineers Ag

Inventors

• Petkov Kaloian

Classifications

• G06T15/506

  Illumination models · CPC title

• G06T2210/41

  Medical · CPC title

• G06T15/06

  Ray-tracing · CPC title

• G06T15/83

  Phong shading · CPC title

• G06T15/60

  Shadow generation · CPC title