Assessment of cervical spondylotic myelopathy using diffusion tensor magnetic resonance imaging parameter at 3.0 tesla.
METHODS
Cross-sectional study.


OBJECTIVE
To assess spinal cord condition in patients with cervical spondylosis (CS), using diffusion tensor imaging parameter.


BACKGROUND
Although myelopathy is a common symptom after CS, clinically objective assessment for determination of surgical intervention is not straightforward.


METHODS
Twenty-six patients with CS and 30 normal control subjects were enrolled. Diffusion tensor imaging was obtained using a single-shot fast spin-echo-based sequence at 3.0 T. Mean diffusivity (MD) and fractional anisotropy (FA) were measured in the axial plane at 6 spinal levels. To evaluate MD and FA in patients with CS considering the normal variation at each spinal level and between spinal levels, MD and FA at the most compressed spinal level were transformed to normalized values with a z score. Presence of myelopathy was predicted with the MD and FA z scores. Diagnostic validity of MD and FA was compared with receiver operating characteristic analysis. More effective parameter and the optimal cutoff value for prediction were determined.


RESULTS
In normal subjects, MD and FA were significantly different between spinal levels. In patients with myelopathy, an MD increase or an FA decrease was demonstrated in most cases. Although both an MD increase and an FA decrease had diagnostic validity for myelopathy, receiver operating characteristic analysis demonstrated a higher sensitivity and specificity for prediction of an MD increase than an FA decrease (areas under the curve for MD and FA were 0.903 and 0.760, respectively). An MD z score of 1.40 was considered to be the best diagnostic cutoff value with 100% sensitivity and 75% specificity.


CONCLUSIONS
Myelopathy can be predicted with high accuracy with diffusion tensor imaging parameter, with the MD z score at the most compressed spinal level.


METHODS
3.
Department of Neurosurgery, Osaka City University Graduate School of Medicine, Osaka, Japan. uda_takehiro@hotmail.com
Takehiro
T
Uda
Toshihiro
T
Takami
Naohiro
N
Tsuyuguchi
Shinichi
S
Sakamoto
Toru
T
Yamagata
Hidetoshi
H
Ikeda
Takashi
T
Nagata
Kenji
K
Ohata
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002574:Cervical Vertebrae / Q000473:pathology*; D003430:Cross-Sectional Studies; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D013116:Spinal Cord / Q000473:pathology*; D013117:Spinal Cord Compression / Q000209:etiology / Q000473:pathology*; D055009:Spondylosis / Q000150:complications / Q000473:pathology*; D055815:Young Adult