# QFR

**Repository Path**: bigduduwxf/QFR

## Basic Information

- **Project Name**: QFR
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-01-16
- **Last Updated**: 2025-02-27

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# QFR calculation steps

The following
steps were used as standard operation procedures in
the study: \
(1) two image sequences acquired at two
arbitrary angiographic views with projection angles at
least 25 degree apart were loaded; \
(2) automated calibration
or manual catheter calibration if the so-called Pixel
Spacing parameter was not recorded by the X-ray
systems was performed; \
(3) properly contrast-filled
end-diastolic (ED) frames of these angiographic
image sequences were selected; \
(4) one to three
anatomical markers, e.g., bifurcations, were identified
as reference points in the two angiographic views for
the automated correction of angiographic system
distortions; \
(5) the vessel segment of interest was
defined and automated 2D lumen edge detection was
performed using our extensively validated QCA
algorithms [1,2]; \
(6) automated 3D reconstruction
and modeling techniques were performed. The resulting lumen surface modeled with elliptical crosssections and the so-called reference surface modeled
with circular cross-sections were generated. Quantitative data including the global parameters, e.g., lumen
volume, diameter and area stenoses, and the local
parameters at every position along the vessel segment
of interest, e.g., short diameter, long diameter, and
area were automatically reported.
## Step 5.1 Wavefront algorithm[1]
* Select the start point and end point in the origin image 

![origin image](./figure/angiogram.png)

* Define the speed function

![speed function](figure/speedFunction.png)

* Calculate the arrival times from start point to the end point)

![arrival_times.png](./figure/arrival_times.png)

## Step 5.2 Backtracking algorigthm[1]
* Back track the path line from the arrival times matrix

![pathline image](./figure/pathline.png)

![pathline image](./figure/bifurcation.png)

## The first iteration
## Step 5.3 Scaneline and EdgeStrength 
* Create the scaneline of the pathline

![scaneline image](./figure/scaneline.png)

* Resample the origin image base on the scaneline

![scaneline resample image](./figure/scanelineResample.png)

* Calculate the edge strength of the resampled image on the scaneline

![edge Strength image](./figure/edgeStrength.png)

## Step 5.3 MCA
* Detect the countour of the edgeStrength

![mcadetect image](./figure/mcadetect.png)

* Map the countour to the origin image

![countour image](./figure/countour.png)

* Smooth the Countour

![SmoothedCountour image](./figure/smoothedCountour.png)
![countour image](./figure/countour3.png)

## The second iteration( not finished )
1. Use the centerline created by the countour in step 5.3
2. Run step 5.3 and step 5.4 again

![secondScaneline image](./figure/secondScaneline.png)
![secondIteration image](./figure/secondIteration.png)

## The reference diameter function

## Step 6.1 reconstruction 3D centerline :hourglass:
![centerline1 image](./figure/centerline1.jpg)
![centerline1 image](./figure/centerline2.jpg)
![centerline1 image](./figure/centerline3D.jpg)

## Step 6.2 modeling lumen surface :hourglass:

## Step 6.3 modeling reference surface :hourglass:

## Step 6.4 calculate the global parameters :hourglass:

## References

1.  Janssen JP, Koning G, de Koning PJH, et al. A novel approach for the detection of pathlines in x-ray angiograms: the wavefront propagation algorithm. Int J Cardiovasc Imaging. 2002;18:317–324.

2. Tuinenburg JC, Koning G, Rareş A, Janssen JP, Lansky AJ, Reiber JH. Dedicated bifurcation analysis: basic principles. Int J Cardiovasc Imaging. 2011 Feb;27(2):167-74. doi: 10.1007/s10554-010-9795-9. Epub 2011 Feb 17. PMID: 21327913; PMCID: PMC3078323.

3. Tu S, Xu L, Ligthart J, Xu B, Witberg K, Sun Z, Koning G, Reiber JH, Regar E. In vivo comparison of arterial lumen dimensions assessed by co-registered three-dimensional (3D) quantitative coronary angiography, intravascular ultrasound and optical coherence tomography. Int J Cardiovasc Imaging. 2012 Aug;28(6):1315-27. doi: 10.1007/s10554-012-0016-6. Epub 2012 Jan 20. PMID: 22261998; PMCID: PMC3463784.

4. Yang J, Wang Y, Liu Y, Tang S, Chen W. Novel approach for 3-d reconstruction of coronary arteries from two uncalibrated angiographic images. IEEE Trans Image Process. 2009 Jul;18(7):1563-72. doi: 10.1109/TIP.2009.2017363. Epub 2009 May 2. PMID: 19414289.

5. Ramcharitar S, Onuma Y, Aben JP, Consten C, Weijers B, Morel MA, Serruys PW. A novel dedicated quantitative coronary analysis methodology for bifurcation lesions. EuroIntervention. 2008 Mar;3(5):553-7. doi: 10.4244/eijv3i5a100. PMID: 19608480.