Three-dimensional magnetic resonance imaging ultrashort echo-time cones for assessing lung density in pediatric patients.
Pediatr Radiol
; 51(1): 57-65, 2021 01.
Article
in En
| MEDLINE
| ID: mdl-32860525
ABSTRACT
BACKGROUND:
MRI of lung parenchyma is challenging because of the rapid decay of signal by susceptibility effects of aerated lung on routine fast spin-echo sequences.OBJECTIVE:
To assess lung signal intensity in children on ultrashort echo-time sequences in comparison to a fast spin-echo technique. MATERIALS ANDMETHODS:
We conducted a retrospective study of lung MRI obtained in 30 patients (median age 5 years, range 2 months to 18 years) including 15 with normal lungs and 15 with cystic fibrosis. On a fast spin-echo sequence with radial readout and an ultrashort echo-time sequence, both lungs were segmented and signal intensities were extracted. We compared lung-to-background signal ratios and histogram analysis between the two patient cohorts using non-parametric tests and correlation analysis.RESULTS:
On ultrashort echo-time the lung-to-background ratio was age-dependent, ranging from 3.15 to 1.33 with high negative correlation (Rs = -0.86). Signal in posterior dependent portions of the lung was 18% and 11% higher than that of the anterior lung for age groups 0-2 and 2-18 years, respectively. The fast spin-echo sequence showed no variation of signal ratios by age or location, with a median of 0.99 (0.98-1.02). Histograms of ultrashort echo-time slices between controls and children with aggravated cystic fibrosis with mucus plugging and wall thickening exhibited significant discrepancies that differentiated between normal and pathological lungs.CONCLUSION:
Signal intensity of lung on ultrashort echo-time is higher than that on fast spin-echo sequences, is age-dependent and shows a gravity-dependent anterior to posterior gradient. This signal variation appears similar to lung density described on CT.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Image Interpretation, Computer-Assisted
/
Cystic Fibrosis
Type of study:
Observational_studies
Limits:
Child
/
Humans
/
Infant
/
Newborn
Language:
En
Journal:
Pediatr Radiol
Year:
2021
Document type:
Article
Affiliation country:
Switzerland