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<b>A</b>

<b>li</b>

<b>ti</b>

<b>f f</b>

<b>t</b>

<b>i</b>

<b>Application of fast scanning </b>

<b>technique “compressed SENSE” on </b>

<b>MR system Philips Ingenia 1.5T</b>

<i><b>Phan Anh Phuong;</b> Nguyễn Cơng tiến; Nguyễn Văn Hịa; </i>

<i>Lê Văn Tài; Trần Duy Hưng; Nguyễn Tuấn Dũng; Lê Xuân Thanh</i>
<i>Radiology center in Bach Mai hospital</i>

Advantages of MRI

• Powerful imaging modality for clinical
• Noninvasive examination of the body
• does not use ionizing radiation

• High soft‐tissue characterization with flexible image‐contrast 
parameters

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Disadvantages of MRI

• Has been relatively slow compared to other imaging modalities such 
as CT

• Low speed, thus long examination times 

• Limit spatial resolution and volumetric coverage
• sensitivity to respiratory motion

<b>The goals in MRI</b>

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Compromises in MRI

The invention of fast MR Imaging

strategies

• Fast Low Angle Shot (FLASH)
• Fast Spin‐ Echo(FSE) Imaging
• Echo‐Plana Imaging

• Since Late 1990s Parallel Imaging techniques were proposed

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Parallel Imaging

MRI questions.com

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0

‐

20

 

times

JPEG VS RAW

1

0

The concept of compressed sensing, which was originally 

proposed in the early 2000s by Donoho and Candès

K - space transform in MRI

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Only centre and periphery of K - Space

<b>TF</b>

<b>TF</b>

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Compressed

SENSE principle

The goal image Incoherent 
subsampling

Wavelet transform
Denoising by threshold

Compressed SENSE principle

Wavelet 

transform and 

denoised
saparsity
Incoherent

undersampling

Non‐liner iterative 

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Philips Compressed SENSE

<i>(2D, 3D, 4D, all anatomies, all MRI sequences)</i>

=

=

SENSE

+

Compressed Sensing

<i>(2D, 3D, 4D, all anatomies) (3D, body area)</i>

Conventional sequences VS compressed SENSE

43%
400
600
800
T2_TSE_SAG
_0.8X0.8X4
mm_3.33S
T1_TSE_SA
G_0.8X0.8X

4mm_3.36S
CS_T2_TSE_SAG
_0.8X0.8X4mm
_2.02S
CS_T1SAG_T
SE_0.8X0.8X
4mm_2.00S
T2_AX_TSE_0.8X0.
8X4mm_3.36S
CS_T2_AX_TSE_0.8
X0.8X4mm_2.07S

10.45s 0 6.09s

200
400

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CS_FLAIR_AX_FS_
0.69x1.1_RE1.3_2.58S

CS_T2_TSE_AX_

0.6x0.75_1.42S_RE 1.5 TOF_CS SENSE_0.6x0.9_RE3_2.59S

7.39s
0
200
400
600
800

TIME
NON_CS CS
32%

FLAIR AX_FS_0.69x1.1_3.50S T2_TSE_AX_0.6x0.75_2.31S TOF_SENSE_0.6x0.9_4.47S

11.08s

Application on Philips 1.5T Ingenia

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Application on Philips 1.5T Ingenia

CS_T1 3D_TSE_FS Sag_1.1.1mm_3:18s(CS=5)

Application on Philips 1.5T Ingenia

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`

Increase resolution

T2_SAG_TSE_1x
1.35x4mm_59S

CS_T2_SAG_TSE_0.8x0.8X4mm_

59S_RE 1.6_FOV280mm

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Up to 50% acceleration

Acceleration for <b>all2D & 3D </b>anatomical contrasts, <b>100% coverage</b>on all anatomies

Body

Brain Spine MSK

Vascular

Cardiac Breast Whole body

compatible

• 2D and 3D sequences
• Fat saturation

• Dark fluid
• Dixon
• T1, T2, PD

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Drawback

• Cannot be used:

• EPI

• Multislice‐TSE with partial NSA is used( half scan)
• Non‐Cartesian scans( multiVane )

• OMAR
• spectroscopy

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Compressed SENSE- conclusion

• Faster imaging, higher system throughput
• Image quality improvement is possible
• Applicable in all anatomical regions
• Work with almost 2D, 3D sequences

• Easier for breath hold/ faster for dynamic imaging
• New high end study become possible

• New high‐end study become possible

</div>

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