Restoring CT scan data

Patent metadata

Field	Value
Publication number	US-9861325-B2
Application number	US-201514940155-A
Country	US
Kind code	B2
Filing date	Nov 13, 2015
Priority date	Nov 13, 2014
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

A method for restoring CT scan data is disclosed. The method may comprise: building a data collecting model with respect to a specific direction of a detector based a response curve of the detector. In some examples, the specific direction can indicate a channel direction and a slice direction of the detector. During a CT scanning, based on the data collecting model, X-ray intensity values detected by the detectors in the specific direction can be acquired. A function can be determined such that it satisfies the data collecting model, a continuity condition and a boundary condition, An X-ray intensity value can be obtained by substituting the coordinate value of a point in the specific direction into the function.

First claim

The invention claimed is:

1. A method for restoring CT scan data, the method comprises:
building a data collecting model with respect to a specific direction of a detector based on a response curve of the detector, wherein the specific direction indicates a channel direction and/or a slice direction of the detector;
acquiring, based on the data collecting model, X-ray intensity values detected by the detector in the specific direction during a CT scanning;
determining a function which satisfies a relationship of the data collecting model with respect to the acquired X-ray intensity values in the specific direction, a continuity condition and a boundary condition; and
calculating an X-ray intensity value of a point in the specific direction by substituting a coordinate value of the point into the function.

2. The method of claim 1 , wherein the data collecting model is a data collecting model with respect to a channel direction of the detector and is defined by the following equation:

y
ij

=

∫

x
=

x
i

x
=

x

i
+
1

⁢

K
ij

⁡

(
x
)

⁢

A
ij

⁡

(
x
)

⁢

⁢
d
⁢

⁢
x

;

wherein, x represents the coordinate value in a channel direction of the detector,
i represents a channel index and is an integer ranging from 1 to a maximum value of N,
j represents a slice index and is an integer ranging from 1 to a maximum value of M,
y ij represents an X-ray intensity value detected by the detector at the j th slice and the i th channel,
K ij (x) represents a response curve in a channel direction of the detector at the j th slice and the i th channel,
A ij (x) represents a real X-ray intensity value in a channel direction of the detector at the j th slice and the i th channel,
x i represents a minimum coordinate value in a channel direction of the detector at the i th channel, and
x i+1 represents a minimum coordinate value in a channel direction of the detector at the (i+1) th channel.

3. The method of claim 1 , wherein the data collecting model is a data collecting model with respect to the slice direction of the detector and is defined by the following equation:

y
ij

=

∫

z
=

z
j

z
=

z

j
+
1

⁢

K
ij

⁡

(
z
)

⁢

A
ij

⁡

(
z
)

⁢

⁢
d
⁢

⁢
z

;

wherein, z represents a coordinate value in a slice direction of the detector,
i represents a channel index and is an integer ranging from 1 to a maximum value of N,
j represents a slice index and is an integer ranging from 1 to a maximum value of M,
y ij represents an X-ray intensity value detected by the detector in at j th slice and the i th channel,
K ij (z)represents a response curve in a slice direction of the detector at the j th slice and the i th channel,
A ij (z) represents a real X-ray intensity value in a slice direction of the detector at the j th slice and the i th channel,
z j represents a minimum coordinate value in a slice direction of the detectors at the j th slice, and
z j+1 represents a minimum coordinate value in a slice direction of the detectors at the (j+1) th slice.

4. The method of claim 1 , wherein, the data collecting model is a data collecting model with respect to a channel direction and the slice direction of the detector and is defined by the following equation:

y
ij

=

∫

x
=

x
i

x
=

x

i
+
1

⁢

∫

z
=

z
j

Assignees

• Shenyang Neusoft Medical Sys

Inventors

• Lou Shanshan
• Zhao Jiangwei

Classifications

• G06T12/10

  Image preprocessing, e.g. calibration, positioning of sources or scatter correction · CPC title

• A61B6/5205

  involving processing of raw data to produce diagnostic data · CPC title

• A61B6/032 Primary

  Transmission computed tomography [CT] · CPC title

• G06T11/005

  Physics · mapped topic