Dual-energy radiography process differentiating bone tissues, lean tissues and fatty tissues

• US 20030133538A1
• Filed: 12/09/2002
• Published: 07/17/2003
• Est. Priority Date: 12/07/2001
• Status: Active Grant

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: Robert-Coutant, Christine, Dinten, Jean-Marc, Herve, Lionel
• Granted Patent: US 6,857,640 B2
• Time in Patent Office: Days
• US Class Current: 378/53
• CPC Class Codes: A61B 6/482 involving multiple energy imaging
• CPC Class Codes: A61B 6/505 for diagnosis of bone

Abstract

This radiography process utilizes dual-energy rays and comprises, in order to differentiate bone, lean and fatty tissues at the same time, an improvement consisting in assessing the total length penetrated by each ray while correcting the errors which may be produced by internal gas pockets. One proceeds as follows: selection of certain rays which have not penetrated bone tissues; calculation of the thicknesses of lean and fatty tissues penetrated by these rays according to the two attenuations, the sum of these two thicknesses being the length of attenuation; estimation of the length of attenuation elsewhere, in particular by means of interpolations; and calculation of the thicknesses of the three categories of tissues penetrated according to this total length of attenuation and the two attenuations.

Claims

1. A radiography process by means of dual-energy rays comprising a differentiation among bone, tissues, lean tissues and fatty tissues of an organism penetrated by the rays and estimations of thicknesses of the lean tissues, bone tissues and fatty tissues penetrated by the rays, characterized in that it comprises the following stages:

selection of certain rays, which have not penetrated bone tissues;

calculation of the sums of the thicknesses of lean tissues and fatty tissues penetrated by the selected rays according to the attenuations sustained at the said two thicknesses of lean tissues and fatty tissues;

calculation of the total lengths penetrated by the rays in the organism, which are equal to the said sums for the selected rays and are estimated by means of interpolations between said sums for other rays;

and calculation of the thicknesses of bone tissues, lean tissues and fatty tissues penetrated by the rays according to the attenuations sustained at the two energies and the total lengths.