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Copyright © Siemens AG 2010. All rights reserved.

Emerging MRI Techniques for Abdominal and Pelvic Imaging

Brian M. Dale, PhD

Page 2 Sep-2010Copyright © Siemens AG 2010

H CSG MR R&DBrian M. Dale, PhD

Background

PhD in Biomedical Engineering – 2004Case Western Reserve UniversityCleveland, OHSequence programmingOptimal design

Collaboration Manager Siemens HealthcareCary, NCIDEA and Physics TeamAbdominal MRI at 3 T



Outline

Hepatic fat quantificationAbdominal workflowMRI of the female pelvis

Cancer characterization with 4D imagingWill not cover in depth

FDA constraintsOverlap with Dr. Lin

ReferencesFritz-Hansen T, Rostrup E, et al. MRM. 1996 Aug; 36(2):225-31, Rijpkema M, Kaanders JHAM, et al. JMRI 2001; 14: 457-463.Parker GJ, Jackson A, et al. In: Proc. ISMRM, 2003. p 1264. Parker GJ, Roberts C, et al. MRM. 2006 Nov;56(5):993-1000.



Fatty Liver Disease Progression

Incidence10% - 24% overallUp to 75% of obese

Primary FLDNAFLDNASH

Secondary FLDAlcoholicHepatitisDrug-inducedSurgically-induced



Cirrhosis

SymptomsFatigue Bleeding/brusingNausea Weight loss Ascites

DiagnosisLiver biopsyFibroTest

IrreversiblePrevent further damageLiver transplant

Wikipedia



How Can We Detect FLD Early?

Early Stage FLDTreatableAsymptomaticFat is present

MR Signal CharacteristicsShort T1Chemical shift 3.5 ppm

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Sequence Overview

3D spoiled steady state T1 weightedDual-echo

In-phaseOpposed-phase

Single breath-holdRoutine liver examDixon reconstruction

TerminologySiemens: VIBE DixonGE: Lava IDEALPhilips: mDixon



Physics – Microenvironment Magnetic Shielding

© 2006 Denis Hoa et al, Campus Medica. www.e-mri.org



Opposed Phase – Destructive Interference

© 2006 Denis Hoa et al, Campus Medica. www.e-mri.org



Standard IP/OP Approach

In- and Opposed-Phase ImagesMagnitude reconstructionSignal drop due to fat/water cancellationPure voxels un-cancelledAmbiguous

In-Phase Opposed-Phase



Fat

Wat

er


Fat

Wat

er


VIBE Dixon Approach

In- and Opposed-Phase ImagesMagnitude and phase reconstructionUnambiguous fat/water separationPhase unwrapping required



Fat Only Water Only

Fat Percentage Map

Quantitative Measure of Fat

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Remaining Limitations

Unproven for early stage FLDNo good gold standardLiver biopsyFocal disease

Phase unwrapping errorsMathematically ill-posed



Abdominal MR Exam Workflow

Long duration compared to CTExpensiveError prone

Value added timeImage acquisition

Non-value added timeCoil set-upLocalizersAdjustmentsBreathing commandsContrast delayParameter changes

Hardware solutionsDockable tableArray coils

Software solutionsParallel imagingAutomatic localizationParameter optimizationProtocol strategiesAutomatic voice commands

TerminologySiemens: DOTPhilips: Smart ExamGE: ?



Dot*Day optimizing throughput Engine

PersonalizedBest possible results for virtually any type of patient

GuidedGuides the novice user helping them to scan more expertly

AutomatedWith intelligent, automated workflows a new level of efficiency can be reached

*The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S..



Personalized

Software for best possible results for virtually any type of patient

Strategies for uniquely tailored, optimized scans configurable to patient condition or clinical question

Avoid failed scans while improving standard of care




PersonalizedEvery patient is different – different breathhold

Abdomen and cardiac - just state patients breathhold capability –Dot* adapts to each patient’s breathhold capacity and links to your best scanning protocol to match

Breathhold settings can be changed at any time during the exam

Easy set-up of the best scan for each patient – higher resolution and reduction of errors




Dot* guides the novice user helping them to scan more expertly

This enables results with greater efficiency at all levels and improved image consistency

Excellent results – guided intuitively


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MRCP

Guided The right choice when needed

Your decisions are seamlessly integrated into the scanning process

After a decision is taken, Dot* automatically links to yourprotocol and updates the queue

E.g. for Abdomen – MRCP or Diffusion

One click, less mistakes, faster




With intelligent, automated workflows – customizable to your standards – a new level of efficiency can be reached

Scans are completed faster and more easily with less chance of errors or repeats


Automated



Automated Dynamic VIBE Timing

Timing is never off –synchronized contrast timing and breathing

AutoBolusDetection – more accurate contrast timing

Voice commands integrated into the scanning workflow

Automatically played at the right point in time - synchronized timing of scanning and breathing

Personalized voice commands –easy language selection

Easily selectedAutomatically played




AutomatedAutomated abdominal exam

Timing is never off – even inserting sequences between venous and delayed

Intelligent automation – no navigator positioning, no FoVadaptations necessary anymore

Reduced user interaction – be fast, with excellent image quality

Comprehensive liver exam in only 15 min*

Also available for TimCT Onco

Video: 19 s

* Results may vary. Data on file. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S..




Unproven time savings

Community acceptance

Customization

Best practices strategies



Standard Female Pelvis Protocol

3-plane localizer

Sagittal, axial, & coronal 2D TSE T2wCongenital anomaliesCancer stagingFibroid treatment planning

Axial 2D TSE T1wCongenital anomaliesCancer stagingFibroid treatment planning

Axial & sag 3D GRE T1w pre- and post-contrastCancer stagingFibroid treatment planning

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3D T2w TSE

Acquire 3D isotropic Reformat any plane

Long echo trainT2 decay causes blurringVariable flip angle refocusing

TerminologySiemens: SPACEGE: CUBEPhilips: Vista



Acquired Offline reconstructed

3D TSE T2w MRI w SPACE



Coronal oblique TSE T2w

Sala E, Seminars in Roentgenology, October 2008

Congenital anomalies

Offline Multiplanar Reformat



Coronal oblique TSE T2w


Cervical cancer




Axial oblique TSE T2w


Endometrial cancer




50 patients (49.4 ± 14.5 yrs)

Ax, cor & sag 2D TSE T2w

Sag SPACE

4 readers

2D TSE T2w vs SPACE

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Acquisition TimeSagittal 3D (+ Recons)

Ax, cor & sag 2D

Mean ± StDev 6:57 ± 0:58 12:11 ± 2:08

Median 6:36 11:28

Minimum 5:17 9:31

Maximum 10:49 19:07

N = 50, unpublished data

Time Savings



SPACE2D

2D TSE T2w vs SPACE



SPACE2D

2D TSE T2w vs SPACE



Image qualityOverall, uterus, ovaries

ContrastEndometrium/junctional zone/myometrium

Cervical epithelium/stroma/parametrium

Vagina/surrounding tissue


Results



Lesion detection


Qualitative Assessment



ArtifactsRespiratory motion

Bowel motion


Qualitative Assessment

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3-plane localizerSingle plane 3D FSE T2wAx 3D dual echo GRE w/wo Gad

“Fast Female Pelvis”




Manual reformat on scannerManual reformat on PACSAutomatic inline reformat

Reformat image qualityOptimal thicknessOblique slices

Small studyMore patientsMore pathologies



Thank You

Acknowledgements

Chen Lin, PhDElmar Merkle, MDVamsi Narra, MDRichard Semelka, MD

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