Tottori J. Clin. Res. 7(1), 49-53, 2016

Lumbar MRI of the young focusing on spondylolysis cases
Akihito Okada*, Shoji Tomita
Department of Radiological Technology, NHO Tottori Medical Center*Correspondence: 876 Mitsu, Tottori 689-0203, Japan
Abstract
We have often conducted lumbar MRI of junior and senior high school students who perform sport activity
and have a chief complaint of persistent low back pain. The disease is often described as ‘spondylolysis’. In thisreport, what we learned from lumbar MRI to examine spondylolysis in the growth period and points to payattention to on the acquisition of images are summarized. The first case was a 17-year-old female with typicalspondylolysis, the second case was a 14-year-old female with unilateral spondylolysis, and the third case was a
14-year-old male with spondylolysis accompanied by a fracture line in the sacral region. In patients suspected
to have spondylolysis, the presence or absence of bone marrow edema in the vertebral arch is confirmed with asagittal view on T2-STIR, and when an abnormally high intensity is observed, the coronal and transverse viewssufficiently including the vertebral arch are imaged. The bilateral vertebral arch regions can be compared oncoronal T2-STIR, and expansion of the lesion can be easily identified. When concomitant sacral bone injury ispresent, coronal T2-STIR images may be useful to make a diagnosis. Tottori J. Clin. Res. 7(1), 49-53, 2016
Keywords: sport orthopedics, spondylolysis, lumbar MRI, T2-STIR, bone marrow edema
Objective
We have often conducted lumbar MRI ofjunior and senior high school students. Many ofthem perform sport activity and visit our hospitalwith a chief complaint of persistent low back pain.
It is often described as ‘spondylolysis’ based on
examination and image interpretation reports.
Initially, we lacked knowledge about spondylolysis
and did not know what we should pay attention toon examination. We performed examinations whileobtaining advice from image-reading physicians
and senior technologists. In this report, wesummarize spondylolysis in the growth period withregard to what we learned from examinations
performed at Hospital A and what we should pay
attention to on the acquisition of images.

accompanying fracture. Among the fat suppression
methods, the T2-STIR method utilizes differencesin the longitudinal relaxation time among tissues,and the inversion time is measured when thelongitudinal magnetization of fat becomes 0. Since
it is unlikely to be influenced by magnetic
homogeneity, a wide acquisition range can be set,but the acquisition conditions should be carefully
set because the signal to noise ratio (SNR) (ratio of
the image intensity to the noise level) may decrease.
Case presentation
1. Typical case of spondylolysis
The patient was a 17-year-old female with achief complaint of low back pain. On sagittal
T2-STIR (Fig. 1), high intensities were noted in thebilateral vertebral arch pedicles of the 5th lumbar
vertebra (Fig. 1A, C). With a transverse view (Fig.
2), these regions showed a low intensity on
T1-weighted imaging (Fig. 2B), a high intensity on
T2-weighted imaging (Fig. 2A), and a distinct highintensity on T2-STIR (Fig. 2C). These are featuresof bone marrow edema, suggesting spondylolysis of
the 5th lumbar vertebra.
Since bone marrow edema is small andunnoticeable, it is necessary to carefully observe theinitially acquired sagittal image.

Acquisition conditions
The MRI acquisition sequence was: sagittal
and transverse views on T1- and T2-weighted andT2-fat suppression (T2-STIR) imaging and acoronal view on T2-STIR imaging. The fat
suppression method depicts fat components in theacquisition area to a low signal. Since the intensityof water-containing tumors and edema is high with
T2-fat suppression, the diagnostic performanceincreases in the presence of bone marrow edema1