Variable echo time imaging for detecting the short T2* components of the sciatic nerve: a validation study.
OBJECTIVE
The aim of this study was to develop and validate an MRI protocol based on a variable echo time (vTE) sensitive to the short T2* components of the sciatic nerve.


MATERIALS AND METHODS
15 healthy subjects (M/F: 9/6; age: 21-62) were scanned at 3T targeting the sciatic nerve at the thigh bilaterally, using a dual echo variable echo time (vTE) sequence (based on a spoiled gradient echo acquisition) with echo times of 0.98/5.37 ms. Apparent T2* (aT2*) values of the sciatic nerves were calculated with a mono-exponential fit and used for data comparison.


RESULTS
There were no significant differences in aT2* related to side, sex, age, and BMI, even though small differences for side were reported. Good-to-excellent repeatability and reproducibility were found for geometry of ROIs (Dice indices: intra-rater 0.68-0.7; inter-rater 0.70-0.72) and the related aT2* measures (intra-inter reader ICC 0.95-0.97; 0.66-0.85) from two different operators. Side-related signal-to-noise-ratio non-significant differences were reported, while contrast-to-noise-ratio measures were excellent both for side and echo.


DISCUSSION
Our study introduces a novel MR sequence sensitive to the short T2* components of the sciatic nerve and may be used for the study of peripheral nerve disorders.
['Felisaz|Paolo Florent|PF|', 'Belatti|Eugenio|E|', 'Deligianni|Xeni|X|http://orcid.org/0000-0001-9968-223X', 'Bergsland|Niels|N|', 'Santini|Francesco|F|', 'Paoletti|Matteo|M|', 'Solazzo|Francesca|F|', 'Germani|Giancarlo|G|', 'Cortese|Andrea|A|', 'Vegezzi|Elisa|E|', 'Bieri|Oliver|O|', 'Bastianello|Stefano|S|', 'Pichiecchio|Anna|A|']
D000328:Adult D005260:Female D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D015203:Reproducibility of Results D012584:Sciatic Nerve D055815:Young Adult
Validation study Peripheral nerves Fibrosis Magnetic resonance imaging