Table C.8.27.4-1 describes the parameters used for processing an Intravascular Optical Coherence Tomography polar data image.
Table C.8.27.4-1. Intravascular OCT Processing Parameters Module Attributes
|
Attribute Name |
Tag |
Type |
Attribute Description |
|---|---|---|---|
|
OCT Z Offset Applied |
(0052,0026) |
1 |
Indicates whether or not Z offset correction was applied to the OCT image frames. Enumerated Values:
|
|
Refractive Index Applied |
(0052,003A) |
1 |
Indicates whether or not Refractive Index correction was applied. Enumerated Values:
See Section C.8.27.4.1 for further explanation. |
|
A-line Pixel Spacing |
(0052,0014) |
1 |
Spacing of pixels in the A-line (X-axis), in mm. |
|
Pixel Intensity Relationship |
(0028,1040) |
1 |
The relationship between the pixel sample values and the IVOCT A-line intensity. See Section C.8.27.4.2. |
|
First A-line Location |
(0052,0034) |
1 |
Orientation in degrees at which the 1st A-line in the frame should be displayed. Value shall be between 0 and 360, with zero representing vertical. |
For Refractive Index Applied (0052,003A) a value of YES indicates that Effective Refractive Index (0052,0004) correction has been applied to the reported A-line Pixel Spacing (0052,0014) attribute. A value of NO indicates that Effective Refractive Index (0052,0004) correction has not been applied (i.e., A-line Pixel Spacing corresponds to the pixel spacing in air).
Pixel Intensity Relationship (0028,1040) shall identify the relationship of the pixel values to the IVOCT A-line intensity.
Defined Terms:
Approximately proportional to A-line intensity.
Non-linear "Log Function"; A Pixel Intensity Relationship LUT shall be included with the image to allow it to be scaled back to its proportional A-line intensity value.