Angiographic method for examining a vascular system

Patent metadata

Field	Value
Publication number	US-9031295-B2
Application number	US-201313963265-A
Country	US
Kind code	B2
Filing date	Aug 9, 2013
Priority date	Aug 13, 2012
Publication date	May 12, 2015
Grant date	May 12, 2015

Abstract

An angiographic method is provided. The method includes: identification of a relevant part in acquired angiography 4D sequences which exhibit a vascular disorder or change; determination of a centerline for the part; ascertainment of lines parallel and surrounding the centerline; specification of perpendicular cross-sections; determination of voxels; ascertainment of bolus curves as a function of time for each voxel; which intersects one of the cross-sections; determination of a time for each voxel; measurement of the true Euclidean distance between voxels at the positions along the centerline and the parallel lines; division of the measured distance by the time difference; determination of second speed components, running transversely, proportional to the relative change in mass for each voxel; and calculation of the blood flow in the relevant part of the vascular system on the basis of the speed components.

First claim

The invention claimed is:

1. An angiographic method for examining a vascular system of an object under examination in order to determine flow characteristics inside vessels, comprising:
S 1 ) acquiring 4D angiography sequences;
S 2 ) identifying a relevant part of the vascular system in the 4D angiography sequences which could exhibit a vascular disorder or vascular change;
S 3 ) determining a centerline for the identified relevant part;
S 4 ) ascertaining of parallel lines which run parallel to the centerline and surround the centerline;
S 5 ) specifying perpendicular cross-sections at least at positions which can be determined or chosen along the centerline;
S 6 ) determining voxels lying on the perpendicular cross-sections;
S 7 ) ascertaining bolus curves as a function of time for each voxel which intersects one of the cross-sections;
S 8 ) determining a time for each of said voxels;
S 9 ) measuring of the true Euclidean distance between voxels at the positions along the centerline and the parallel lines;
S 10 ) dividing said measured distance by the time difference in order to obtain the amplitude of a first speed component of the blood flow speed in each of said voxels;
S 11 ) determining second speed components, running transversely, proportional to the relative change in mass of the blood in the voxels, for each of said voxels and
S 12 ) calculation of the blood flow in the relevant part of the vascular system on the basis of the speed components.

2. The angiographic examination method as claimed in claim 1 ,
wherein the acquisition of the 4D angiography sequences takes place in accordance with step S 1 ) from rotational angiography projections which are superimposed by means of perspective back projection in a static 3D image of the vascular tree.

3. The angiographic examination method as claimed in claim 1 ,
wherein the calculation of the second speed components, running transversely occurs in accordance with S 11 ) according to the formula:

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4. The angiographic examination method as claimed in claim 2 ,
wherein the calculation of the second speed components, running transversely occurs in accordance with S 11 ) according to the formula:

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5. The angiographic examination method as claimed in claim 1 ,
wherein accordance with S 8 ) the time is the maximum time, rise time of the wash-in phase and/or fall time of the wash-out phase of the bolus curve.

6. The angiographic examination method as claimed in claim 2 ,
wherein accordance with S 8 ) the time is the maximum time, rise time of the wash-in phase and/or fall time of the wash-out phase of the bolus curve.

7. The angiographic examination method as claimed in claim 3 ,
wherein accordance with S 8 ) the time is the maximum time, rise time of the wash-in phase and/or fall time of the wash-out phase of the bolus curve.

Assignees

• Klingenbeck Klaus
• Siemens Ag

Inventors

• Klingenbeck Klaus

Classifications

• A61B6/5217

  extracting a diagnostic or physiological parameter from medical diagnostic data · CPC title

• A61B6/507

  for determination of haemodynamic parameters, e.g. perfusion CT · CPC title

• G16H50/30

  for calculating health indices; for individual health risk assessment · CPC title

• A61B6/032

  Transmission computed tomography [CT] · CPC title

• A61B6/4441

  the rigid structure being a C-arm or U-arm · CPC title