1. Internship Presentation
Margarita Andreou

2. Subject
Design a mechanical apparatus that holds ultrasound
probes with existing resolution phantoms, in order to
measure ultrasound imaging resolution in a precise and
reproducible manner.

3. List of the requirements
1. The ultrasound scanning plan should be perpendicular
to the phantom surface.
2. The ultrasound scanning plan should intersect the
reflecting objects in an optimal manner.
3. The probe should be easy to install on the holder.
4. The probe should be firmly attached to the holder.
5. The probe repositioning should be repeatable.

4. 1st
design idea
Movement in horizontal way
Movement in vertical way
Probe holder
Cable holder with screws

5. Resolution Measurement Test
Third target group(10.5 cm depth)
Time: 4 min
Without holder With holder
Axial Resolution
(mm)
Lateral Resolution
(mm)
Axial
Resolution (mm)
Lateral Resolution
(mm)
0.5 2 0.5 1
0.5 1 0.5 1
0.5 1 0.5 1
0.5 2 0.5 1
0.5 1 0.5 1
Results 5/5 3/5 5/5 5/5

6. Problems of the prototype
1. The cable holder is not easy to setup.
2. The measurement is not very fast.
3. The vertical tube is not well controlled.
4. The right arm of the holder is hard to slide.
5. The probe repositioning is not repeatable.
The technical problems occurred mainly due to assembly
To eliminate these problems a new apparatus was builded with more stable
materials and with parts that are easier to assembly.

7. 2nd
design idea
It consists of optical rails that
can be used for quick and
repeatable alignment and of
optical rail carriers.

8. Resolution Measurement Test
Axial
Resolution
(mm)
Lateral
Resolution
(mm)
Time
(min:sec)
0.5 1 2:07
0.5 1 2:50
0.5 1 1:20
Results 3/3 3/3 2:05
Third target group(10.5 cm depth)
Axial
Resolution
(mm)
Lateral
Resolution
(mm)
Time
(min:sec)
0.5 2 1:40
0.5 2 2:52
0.5 2 2:07
0.5 2 2:50
0.5 2 1:20
Results 5/5 5/5 2:10
Second target group(6.5 cm depth)

9. Conclusion
1. The measurement are fast and reproducible
2. The holder is stable.
3. The use of the holder is easy.
4. The probe repositioning is repeatable.
5. The probe is easy to install on the holder.

10. Resolution Quantification in Matlab
With the use of matlab, a program is made to process the
image which are taken from aixplorer.
The program helps to give a reproducible results for the
resolution of the images.
The program give to the user the axial and lateral resolution
for the 6.5 and 10.5 cm target groups.

11. 1. The program reads the image, converts it in grayscale
and computes the pixel dimensions.
Resolution Quantification in Matlab

12. 2. It finds the center point of the image, which are there
where the vertical and horizontal wire targets are intersect.
Resolution Quantification in Matlab

13. 3. It zooms in the desired area either the 6.5 cm depth target
group or the 10.5 cm target group and it put in every target a
cross.
Resolution Quantification in Matlab

14. 4.It makes pairs between the neighbor
targets.
With the yellow lines are the pair for axial
resolution and with blue line is the pair for
lateral resolution.
For each pair it measure the brightness.
Resolution Quantification in Matlab

15. If the brightness is zero then the targets can not be distinguished and they
appear with red line.
It finally gives to the user the axial and the lateral resolution.
Resolution Quantification in Matlab

16. Images
Different gain, focal zone, attenuation, zoom,
depth and combination of them.
With and without the holder.
Images with the XC6-1 and SL10-2 probe.
Images with the CIRS 040GSE phantom

18. Conclusion
The resolution are not depend on the gain, on the attenuation and on
the zoom.
For depth 10 cm the axial resolution depends of the focal zone. For
bigger depth the resolution is independent from the focal zone.
The focal zone must be as close as it can to the target group and just
after of it.
The combination of 20% gain and 10cm depth gives the greatest axial
resolution that can be achieved in the second target group.
The program cannot work with the images that are taken without the
holder, because of the rotation.

19. Results at 6.5 cm target group
(default conditions)
Axial Resolution(mm) Lateral Resolution(mm)
1 2
1 2
1 2
1 2
1 2
Results 5/5 5/5

20. Results at 10.5 cm target group
(default conditions)
Axial Resolution(mm) Lateral Resolution(mm)
0.5 2
0.5 2
0.5 2
Results 3/3 3/3

21. Comparison results
Visual Results Matlab Results
Target group Axial Resolution
(mm)
Lateral
Resolution(mm)
Axial Resolution
(mm)
Lateral
Resolution(mm)
10.5 cm
0.5 1 0.5 2
0.5 1 0.5 2
0.5 1 0.5 2
6.5 cm
0.5 2 1 2
0.5 2 1 2
0.5 2 1 2
0.5 2 1 2
0.5 2 1 2

22. Conclusion
1.The program helps to have reproducible results
without the human subjective assessment.
2.The test with the use of matlab is easier and
faster.
3. The program can be easily transfer to non-expert
users, like an operator in a factory.