Type:
Educational Exhibit
Keywords:
Congenital, Calcifications / Calculi, Cholangiography, Contrast agent-intravenous, Ultrasound, MR, Liver, Biliary Tract / Gallbladder, Abdomen, Cysts, MR-Cholangiography
Authors:
L. Esposto Ultimo1, M. Travali2, A. Chiarenza3, M. G. Scuderi1, V. di benedetto1, P. V. Foti1, G. Belfiore1, A. Basile1, S. Palmucci1; 1Catania/IT, 2Catania, Catania/IT, 3Catania /IT
DOI:
10.1594/ecr2018/C-3052
Background
Pediatric patients may be affected by congenital and acquired biliary disease.
The diagnosis should be obtained through US and MRI findings,
in order to avoid ionizing radiation exposure.
MRCP is based on heavy T2-weighted sequences that have high diagnostic capability in showing and emphasizing the biliary tree and pancreatic duct.
However,
in infants or children MRCP represents a diagnostic challenge for radiologists,
with several tips and tricks required to optimize acquisition and protocol.
First of all,
different phased-array coils should be used according to the body size of children: for example,
torso PA coil could be used for the study of the abdomen of a small child.
Due to the reduced thickness of the trunk in children,
spine coils could also be used for pediatric imaging,
exploring the retroperitoneum or the hepatic parenchyma with a good signal-to-noise ratio.
Secondarily,
radiologists and clinicians have to bear in mind that MRCP in infants or small children need to be acquired in sedation.
Therefore,
sequences should be respiratory-triggered or acquired using a navigated abdominal imaging,
to optimize MRCP protocol.
However – for respiratory-triggered imaging – not all centers have a belt adaptable to children; fast and ultrafast imaging – represented by different sequences such as Single-Shot Fast Spin Echo sequences,
Fast Imaging Employing Steady State Acquisition (FIESTA),
balanced Fast Field Echo (BFFE),
True Fast Imaging with Steady State (TrueFISP) – are recommended in MRCP protocol.
Table 1
A final consideration regarding pediatric MRCP concerns the Specific Adsorption Rate (SAR) in babies or infants.
Radiologists and radiographers should reduce SAR during examinations,
principally in neonates; as reported by Darge et al,
expedients that may be adopted in order to maintain an acceptable SAR value are represented by the reduction of number of sections acquired,
the introduction of delay between sequences and the utilization of parallel imaging technique [1].