Optimizing ct scanning parameter

Patent metadata

Field	Value
Publication number	US-2016183905-A1
Application number	US-201514986556-A
Country	US
Kind code	A1
Filing date	Dec 31, 2015
Priority date	Dec 31, 2014
Publication date	Jun 30, 2016
Grant date	—

Abstract

A method for optimizing CT scanning parameter is disclosed. A target group may be generated from a plurality of reference information samples. Each of the reference information samples may include subject information, information indicating a scanning protocol, one or more scanning parameter values and information indicating reconstructed image quality; the target group can consist of one or more reference information samples with the same subject information and the same scanning protocol. A scanning parameter optimization may be performed according to reconstructed image qualities and scanning parameter values of reference information samples in the target group, so as to acquire a target scanning parameter value of the target group. And according to the target scanning parameter value, a reference X-ray irradiation dose corresponding to the scanning protocol and the subject information of the target group may be determined.

First claim

1 . A method for optimizing CT scanning parameter, includes:
acquiring a plurality of reference information samples, wherein each of the reference information samples includes subject information, information indicating a scanning protocol, one or more scanning parameter values and information indicating reconstructed image quality; generating a target group from the plurality of reference information samples, wherein the target group consists of one or more reference information samples with the same subject information and the same scanning protocol; performing a scanning parameter optimization according to reconstructed image qualities and scanning parameter values of reference information samples in the target group, so as to acquire a target scanning parameter value corresponding to the subject information and the scanning protocol of the target group; and determining a reference X-ray irradiation dose according to the target scanning parameter value, wherein the reference X-ray irradiation dose corresponds to the scanning protocol and the subject information of the target group.

2 . The method of claim 1 , wherein, performing the scanning parameter optimization to acquire the target scanning parameter value includes:
selecting an optimal group from the target group, wherein each of the reference information samples in the optimal group has a reconstructed image quality higher than a first preset score; and performing a scanning parameter optimization according to reconstructed image qualities and scanning parameter values of reference information samples in the optimal group.

3 . The method of claim 1 , wherein, the subject information of a reference information sample is determined by:
converting pilot film data of a slice corresponding to the reference information sample or projection data of a field view image in the reference information sample into an equivalent attenuation domain; calculating an equivalent attenuation area according to the data in the equivalent attenuation domain; calculating an attenuation diameter of equivalent water phantom according to the equivalent attenuation area; and taking the attenuation diameter of equivalent water phantom as the subject information of the reference information sample.

4 . The method of claim 3 , wherein, the equivalent attenuation area is calculated as follows:

S
=

∑

i
=
0

N
-
1



(

μ
i



l
i

+

μ

i
+
1



l

i
+
1

)

*

Δ
/
2

;

wherein, the S represents an equivalent attenuation area,
the N represents the number of detecting channels in a CT scanner system,
the μ i represents an average attenuation coefficient corresponding to the i th detecting channel,
the l i represents a length of attenuation path corresponding to the i th detecting channel, and
the Δ represents a distance between centers of two adjacent detecting units.

5 . The method of claim 4 , wherein, the attenuation diameter of equivalent water phantom is calculated as follows:
D scan 2*sqrt(mean( S )/π)/μ water ;
wherein, the D scan represents an attenuation diameter of equivalent water phantom, the μ water represents an attenuation coefficient of water, and the π represents a circumference ratio.

6 . The method of claim 1 , wherein, the subject information of a reference information sample is determined by:
determining the major axis and the minor axis of a reconstructed image corresponding to the reference information sample; simulating an equivalent ellipse according to the major axis and the minor axis; converting the equivalent ellipse into an equivalent circular of the same area; calculating the diameter of the equivalent circular as an equivalent diameter; and taking the equivalent diameter as the subject information of the reference information sample.

7 . The method of claim 1 , wherein, the reference X-ray irradiation dose is determined by calculating with the following equation:

mAs
scan

=

DoesRightFactor
2

*

mAs
ref

*

pow


(

exp


(

-

μ
water

*

D
ref

)

exp


(

-

μ
water

*

D
scam

)

Assignees

• Shenyang Neusoft Medical Sys

Inventors

• Lou Shanshan
• Lv Dan
• Pang Ling
• Liu Changkun

Classifications

• A61B6/032

  Transmission computed tomography [CT] · CPC title

• A61B6/5258

  involving detection or reduction of artifacts or noise · CPC title

• G01T1/00

  Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation (G01T3/00, G01T5/00 take precedence) · CPC title

• G09B23/286

  for scanning or photography techniques, e.g. X-rays, ultrasonics · CPC title

• A61B6/58

  Testing, adjusting or calibrating thereof · CPC title