XiuLan Zhang1, Yongmin Bi2, and Lizhi Xie3
1Radiology Department, The First Affiliated Hospital of Yangtze University, JingZhou, China, 2Department of CT&MRI, Air Force General Hospital, Beijing, China, 3GE Healthcare, China, Beijing, China
Synopsis
T1rho MRI in the lumbar spine may provide a tool for the diagnosis of
early degenerative changes in the disc. In this study, the mean T1rho value of
pilots was significantly lower than that of the control group. The degenerative
grades of pilots mainly were grade III and IV, but control group were grade I
and II. There were significant differences in T1rho values at each age group between
pilots and control group. And overload on spine column of pilots may be the
important reason in degeneration and accelerate the degeneration process.
Purpose
To evaluate early intervertebral disc degeneration quantified by
T1rho and T2-weighted magnetic resonance imaging at 3.0T in asymptomatic
pilots and explore the relationship between intervertebral disc degeneration
and overload.Introduction
Degenerative disc
degeneration is the main cause of low back pain, and also the occupational
diseases of pilots. The pathophysiologic mechanism between disc degeneration
and overload is not well understood. Studies had shown that T1rho MRI in the
lumbar spine may provide a tool for the diagnosis of early degenerative changes
in the disc [1-3]. In this study, the mean T1rho value of pilots was
significantly lower than that of the control group. The degenerative grades of
pilots mainly were grade Ⅲ and Ⅳ, but control group were grade Ⅰ and Ⅱ. There were
significant differences in T1rho values at each age group between pilots and control group, but except
for <30 years group. we concluded that disc
degeneration occurred on pilots was more seriously and the process of
degeneration was more quickly. And overload on spine column of pilots may be
the important reason in degeneration and accelerate the degeneration process. Method
69 Health
volunteers were divided in two groups. pilots group: 34 asymptomatic male
pilots in age from 25 to 51(mean 33.47 ± 7.29 years) without history of
stopping flight or stopping training. The second, control group: 35
asymptomatic volunteers in age from 24 to 48(mean 31.74 ± 6.99 years). Both
sagittal conventional T2- and T1rho-weigted images were acquired at every
examination of lumbar disc. T2-weighted imaging were acquired using a fast
spin-echo sequence with the following parameters: TR=2556ms, TE=121.3ms,
FOV=32×32cm, slice-thickness=4mm, acquisition-matrix=352×320. T1rho-weighted
images used 3D spoiled gradient-recalled sequence with parameters as follows:
TSL1/TSL2/TSL3/TSL4(time of spin lock) =0/20/40/80ms, Spin Lock Frequency=300Hz,
TR=4.2ms, TE=min-full, FOV=260×260mm, NEX=1.0, slice-thickness=5mm,
acquisition-matrix=160×160, bandwidth=62.5kHz, PE direction=L/R. The sagittal
T1rho maps were reformatted for each disk. Mean T1rho values of the central
disk space nucleus pulposus were determined by using post-processing software
namely as T2mapping with the Region of Interests that were approximately 49-51mm². The degenerative grade of each lumbar disc was assessed from
T2-weighted images according to Pfirrmann degenerative grade.
All 69 volunteers were divided into three groups according to age, as <30 years old, 30~40 years old, and≥40 years old groups,
respectively. Results
T1rho values
significantly negatively correlated with Pfirrmann grade(r=-0.901、-0.921,P<0.01)(Figure.1), The mean T1rho value of pilots was significantly
lower than that of the control group (t=3.154,P<0.01).The degenerative grades of pilots mainly were grade Ⅲ and Ⅳ, but control group
were grade Ⅰ and Ⅱ(Z=4.04,P<0.01). There were significant differences in T1rho values at each age
group between pilots and control group (t=4.438、4.646,P<0.01), but except for <30 years group(P>0.05)(Table.1). Evaluation between pilots and control group showed no
difference in T1rho values at each Pfirrmann grade(P>0.05)(Table.2).Discussion and conclusion
Disc degeneration
occurred on pilots was more seriously and the process of degeneration was more
quickly. Overload on spine column of pilots may be the important reason in
degeneration and accelerate the degeneration process. T1rho can be potentially
used as a valid clinical tool in quantitative diagnosis of early intervertebral
disc degeneration in asymptomatic pilots.Acknowledgements
No acknowledgement found.References
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quantification of t1ρ in lumbar spine disk spaces at 3 T using parallel
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