Hong Wang1, Xing Tang1, Panli Zuo2, Shun Qi1, and Hong Yin1
1Department of Radiology, Department of Radiology,Xijing Hospital, Xi'an, China, People's Republic of, 2Siemens Healthcare, MR Collaborations NE Asia, Beijing, China, People's Republic of
Synopsis
MR imaging is limited by poor evaluation of lung
parenchyma due to rapid single decay, low tissue portion density and
substantial respiratory motion. In this study, we evaluate three different
approaches of VIBE sequences in pulmonary lesions detection, which including a
short-TE breath-hold VIBE, DIXON VIBE and a free-breathing Radial VIBE.
We found
Breath-hold short-TE VIBE and Dixon VIBE sequences have better
performance in lesion detection than radial VIBE.Purpose
MR imaging is limited by poor evaluation of lung
parenchyma due to rapid single decay, low tissue portion density and
substantial respiratory motion. In this study, we evaluate three different
approaches of VIBE sequences in pulmonary lesions detection, which including a
short-TE breath-hold VIBE, DIXON VIBE and a free-breathing Radial VIBE.
Methods
This study was approved by the local ethics committee,
and all patients gave written informed consent. 56 patients (42 male and 14
female; mean age, 65.5±9.37; age range, 48-81) with 22 of non-small cell lung cancer
(NSCLC), 10 of small cell lung cancer (SCLC),14 of metastatic tumors,
and 10 of benign were recruited in this study. All MR imaging was performed on
a 1.5 T MR scanner (MAGNETOM Aera, Siemens AG, Erlangen, Germany). Three VIBE
sequences with slice thickness of 3 mm, matrix of 384×288 and FOV of 400×262 mm2
were performed for each patients: 1) breath-hold short-TE VIBE with TR/TE =
4.02/1.91 ms, flip angle = 5 degree, CAIPIRINHA = 2×2, TA = 19 s; 2)
breath-hold Dixon VIBE with TR/TE1/TE2 = 6.75/2.4/4.8 ms, flip angle = 10 degree,
CAIPIRINHA = 2×2, TA = 15s; 3) free-breathing Radial VIBE with TR/TE =
3.84/1.91 ms, flip angle = 12 degree, TA = 212 s. All images were assessed by
two radiologists with 5 and 20 years of experience. The numbers of lesions were
counted for different groups categorized by the short-axis diameter of less
than 10 mm, and larger than10 mm.
Results
A total of 88 lesions were detected by CT, with
28 of a diameter less than 10 mm and 60 of a diameter lager than 10 mm. For 28
lesions with a diameter less than 10 mm,
all were detected by short-TE VIBE and Dixon VIBE, and 20 were detected by
Radial VIBE; and for 60 lesions with a diameter larger than 10 mm, all were
detected by short-TE VIBE and Dixon VIBE, and 56 by Radial VIBE.
Discussion
Lung cancer is the most frequently diagnosed cancer
with one of the highest mortality rates. In this study, we compared three VIBE
sequences in detection of the pulmonary lesions in patients with lung cancer,
and found the breath-hold short-TE VIBE and breath-hold Dixon VIBE sequences
have the similar lesion detection rate. However, the delineation of tumor
boundary was clear in short-TE VIBE. Radial VIBE sequence is useful for
free-breathing examination in patients of young age and pathologies with
difficulties to hold breath during MR examination, but it has lower lesion
detection rate than the breath-hold VIBE sequences.
Conclusion
breath-hold short-TE VIBE and Dixon
VIBE sequences have better performance in lesion detection than radial VIBE.
Acknowledgements
No acknowledgement found.References
No reference found.