abdominal mri · abdominal mri julia geiger. learning objectives ... in the pelvic tumor. what...
TRANSCRIPT
Abdominal MRI
Julia Geiger
Learning objectives
Standard MRI-protocol
No special examinations: MR-Urography, MRCP, MR enterography
Things to consider
Most common pediatric abdominal tumors
2
3
What is important?
Sedation / general anesthesia in younger children
Motion reduction and correctionPROPELLER techniquerespiratory triggeringnavigator pulsefast sequences (drawback low SNR)
Coil selection to address body size
SNR optimization (appropriate sequences and coils, longer acquisition time for compensation of low SNR)
4
Which sequences do you need?
Basic protocol MRI abdomen:
Coronal STIR (isotropic imaging)Coronal T1Transversal T2 fatsat (PROPELLER)Transversal T1
Protocols should include:
Transversal DWIContrast-enhanced T1 fatsatwith dynamic imaging, multiplanar(check GFR)
5
Typical abdominal masses in children
6
• Most common extracranialtumor
• frequently metastatic at diagnosis
• Most common renal tumor• known as Wilms tumor• frequently asymptomatic
Nephroblastoma Neuroblastoma
3 yo boyPainless belly swelling
Echo-inhomogeneous tumorwith cysts/necrotic areas andhemorrhages
pseudocapsule, inhomogeneous signalnecroses, hemorrhageleft kidney with «claw sign»
3 yo boyAbdominal MRI for tumor origin, charcterisation, extent andmetastases
T2 STIR T1 T1 Gad fatsat
3 yo boyMultiplanar sequences including contrast and dwi
T2 fatsat
T1 Gad fatsat
dwi
ADC
Tumor extention in renal veinIVC not affected
3 yo boyMRI enables vessel assessment
T2 fatsat
T1 Gad fatsat
Nephroblastoma
Dumba et al. Cancer Imag 2015
NephroblastomaStaging
Claw sign!
4 yo boyAbdominal swelling, no pain, no dysuria
T1 dyn. Gad fatsat T1 Gad fatsat
Vessel displacement
4 yo boyAbdominal swelling, no pain, no dysuria
T2 fatsat T1
T1 Gad fatsat
DWI ADC
Nephroblastoma = Wilms tumor
• Primitive metanephritic blastema• Most common abdominal tumor 1-8 years• Risc factors: nephroblastomatosis, trisomy 13, 18,
Beckwith Wiedemann syndrome, WT1 and WR2 associated
Imaging:• Large, heterogeneous tumor• Vessel displacement, renal vein and
IVC infiltration• «Claw sign» may be helpful• Lung metastases up to 20% at diagnosis
15
Typical abdominal masses in children
16
2 yo girlReduced general stateAbdominal MRI for tumor origin, charcterisation, extent andmetastases
T2 STIR T2 STIR
heterogeneous signalhemorrhagesmetastasesvessel encasementexceeding midline
2 yo girl
T2 fatsat T1
DWI ADC
Neuroblastomaarising from adrenal gland
3 yo boyabdominal pain, palpable mass in lower abdomen
3 yo boysonography as first line modality
calcifications
3 yo boyAbdominal MRI for tumor origin, charcterisation, extent andmetastases
Neuroforaminal infiltration
T2 fatsat
T2 STIR
T1 Gad fatsat
Neuroblastomaarising from sympathetic chain
23
Whole body MRIcoronal STIR
no metastases
MIBG scintigraphy
no metastases, intense MIBG uptakein the pelvic tumor
What information does the pediatric oncologist need from the radiologist?
1. diagnosis neuroblastoma?
2. vital organs or anatomical structures?
3. complete resection possible?
4. stage of the disease?
5. baseline information for response assessments during therapy
5 month old girlhepatomegaly, restless
5 month old girl
inhomogeneous liver
primary liver tumor vs.Metastases?
Metastastic neuroblastomaOrigin?
T2 STIR T2 STIR
liver and bone marrow metastases
Metastastic neuroblastomaOrigin?
T2 fatsat T1 Gad fatsat
DWI ADC
Neuroblastoma
• Sympathetic chain primitive neural crest cells• Location adrenal vs. extraadrenal retroperitoneum
• often sporadic, partially syndrome-related• heterogeneity of tumor, highly variable prognosis• n-MYC oncogene high risk group
Imaging:• Image-defined risk factors: vessel displacement and
encasement, intraspinal extension, tracheal compression…
• calcifications (90%)• >50% metastases at diagnosis• include whole-body MRI!
Neuroblastoma vs. Wilms Tumor
Dumba et al. Cancer Imaging 2015
Sono, MRI, CTSono, MRI, CTMIBG-Scintigraphy99mTc-ScintigraphyFDG-PET/CT/MRIGa-68 DOTATATE
Take home messages
Take home messages
Abdominal MRI
• appropriate MRI sequences and equipment
• for tumor characterisation, location, extent and staging
• differential diagnosis
• baseline examination, treatment planning and monitoring
• interdisciplinary discussion
• biopsy