mrcp : MR cholangiography

1. MR cholangiography
Lionel Arrivé
Hôpital Saint Antoine Paris
Hanoi nov 7th 2015

2. MRCP
— FSE sequences are very heavily T2-
weighted
— High signal intensity from static fluid
— Classical MRCP included 2D sequences
— Modern MRCP should include 3D
sequences which improve both spatial
resolution and contrast/noise ratio

3. 2D versus 3D
2D 3D
S/N ratio improves with number of source images
TA 2D = TR x Nex x Ny TA 3D = TA 2D x Nz

17. Advantages Limitations
• Near isotropic voxel
• High resolution (1x1x1mm)
• Multiplanar reconstructions
• Excellent signal/noise ratio
• Time of acquisition
• Regular breathing
• Source images analysis
• Multiplanar reconstructions
3D Sequence

30. 2D Sequences
Still useful ?
• Poor quality of 3D sequences
• When one is in a true rush !
• For dynamic analysis

37. Bowel signal suppression
• Paramagnetic contrast (diluted gadolinium)
ou superparamagnetic contrast media
• Blueberry juice
• Black tea
• Pineapple juice (high concentration of
manganese)

40. Complementary sequences
• At least a 3D fat-supressed T1-weighted MR
sequence for detection of biliary stones
• A T2-weighted MR sequence : FSE, SSFSE,
or diffusion-weighted at B0
• Gadolinium injection is only optional

45. Systematic analysis technique
• 3D MRCP : biliary ducts analysis
• T2-weighted MR sequence : liver
heterogeneity and dysmorphia
• T1-weighted MR sequence : biliary stones
• After gadolinium injection : heterogeneity of
contrast enhancement, biliary ducts
enhancement, focal hepatic lesion

46. Systematic analysis technique
• Biliary ducts analysis : moderate or severe
(75%) stenosis, short (2 mm) or long (10 mm),
localized (25%) or diffuse
• Biliary ducts dilatation and biliary stones
• Liver heterogeneity and dysmorphia
• Liver and biliary duct enhancement

47. Systematic analysis technique
• Biliary ducts analysis : moderate or severe
(75%) STENOSIS, short (2 mm) or long (10
mm), localized (25%) or diffuse
• Biliary duct DILATATION and biliary stones
• Liver heterogeneity and dysmorphia
• Liver and biliary duct enhancement

54. Biliary MR Imaging
Multiples traps !
BUT
90% of pitfalls are related to
- Overuse of the term «biliary ducts
irregularities»
- Overinterpretation of hepatic artery mark

55. Biliary MR Imaging
Multiples traps !
BUT
90% of pitfalls are related to
- Overuse of the term «biliary ducts
irregularities»
- Overinterpretation of hepatic artery mark

68. MRCP : other traps
• MR system performances (3D MRCP)
• Patient information : Regular breathing
• Learning curve : inter-observer variability
• Numerous other traps

69. MRCP : other traps
• MR system performances (3D MRCP)
• Patient information : Regular breathing
• Learning curve : inter-observer variability
• Numerous other traps: BILIARY CONTENT

80. Biliary MR Imaging
Multiples traps !
BUT
90% of pitfalls are related to
- Overuse of the term «biliary ducts
irregularities»
- Overinterpretation of hepatic artery mark

81. Biliary MR Imaging
Multiples traps !
BUT
90% of pitfalls are related to
- Overuse of the term «biliary ducts
irregularities»
- Overinterpretation of hepatic artery mark

82. Systematic analysis technique
• Biliary ducts analysis : moderate or severe
(75%) STENOSIS, short (2 mm) or long (10
mm), localized (25%) or diffuse
• Biliary duct DILATATION and biliary stones
• Liver heterogeneity and dysmorphia
• Liver and biliary duct enhancement

85. Conclusion
• 3D MRCP with analysis of source images and
multiplanar and volume reconstruction
• Don’t forget Fat-sat 3D T1-weighted MR sequence
• There is a significant learning curve and analysis should
use a systematic technique
• There is a lot of traps and pitfalls but 90% are related to
misuse of the term « irregularities of biliary ducts » and
to misinterpretation of hepatic artery mark