Segmenting metal objects in projection images

US11321833B2 · kind B2 · utility

Assignee

• Siemens Healthcare Limited · DE

Inventors

• Holger Kunze · Bubenreuth, DE
• Peter Fischer · Bad Neustadt an der Saale, DE
• Björn Kreher · Bräuningshof, DE
• Tristan Gottschalk · Erlangen, DE
• Michael Manhart · Fürth, DE

Key dates

• Filing date: Feb 5, 2020
• Grant date: May 3, 2022
• Expiry date: Apr 5, 2040

Classification

• Technology area (CPC G): Physics
• CPC primary: G06T2207/30196
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

A method for segmenting metal objects in projection images acquired using different projection geometries is provided. Each projection image shows a region of interest. A three-dimensional x-ray image is reconstructed from the projection images in the region of interest. A trained artificial intelligence segmentation algorithm is used to calculate first binary metal masks for each projection image. A three-dimensional intermediate data set of a reconstruction region that is larger than the region of interest is reconstructed by determining, for each voxel of the intermediate data set, as a metal value, a number of first binary metal masks showing metal in a pixel associated with a ray crossing the voxel. A three-dimensional binary metal mask is determined. Second binary metal masks are determined for each projection image by forward projecting the three-dimensional binary metal mask using the respective projection geometries.