High-resolution magnetic resonance imaging and 18FDG-PET findings of the cervical spinal cord before and after decompressive surgery in patients with compressive myelopathy.
METHODS
Evaluation of cervical spinal cord (CSC) of patients with compressive myelopathy by magnetic resonance imaging (MRI) and high-resolution (18F)fluoro-deoxyglucose (18FDG) positron emission tomography (PET).


OBJECTIVE
To determine changes in morphology, intramedullary signal intensity, and glucose metabolic rate in CSC after decompression, and to assess the utility of 18FDG-PET in evaluation of patients with cervical myelopathy.


BACKGROUND
The significance of CSC enlargement after decompression and signal intensity changes within the cord remain elusive. No data are available on metabolic activity of the compressed CSC. Only a few studies have examined correlation between high-resolution MRI and 18FDG-PET neuroimaging in cervical myelopathy.


METHODS
We studied 24 patients who underwent cervical decompressive surgery in terms of postoperative neurologic improvement and changes in MRI and 18FDG-PET. Neurologic status was assessed by the Japanese Orthopedic Association scoring system (17-point scale). Signal intensity change in the cord was qualitatively assessed on both T1- and T2-weighted images. The transverse area of the CSC on MRIs and glucose metabolic rate (standardized uptake value [SUV]) from 18FDG-PET were measured digitally.


RESULTS
Neurologic improvement correlated with preoperative CSC transverse area at maximal compression (P < 0.01) and at follow-up (P < 0.001) and with mean SUV before surgery (P < 0.01) and at follow-up (P < 0.05). Preoperative signal intensity change on MRIs (low intramedullary signal intensity abnormality on T1-weighted image and high intramedullary on T2-weighted image) correlated negatively with neurologic improvement rate (P < 0.05). The transverse area of the CSC was significantly smaller after surgery in patients with preoperative MRI signal intensity changes (P < 0.05). The SUV at follow-up tended to normalize in association with neurologic improvement.


CONCLUSIONS
Our results showed that postoperative neurologic improvement in patients with cervical compressive myelopathy correlated with increased transverse area of the spinal cord, signal intensity change on both T1- and T2-weighted image, and the mean SUV.
Uchida
Kenzo
K
Department of Orthopaedics and Rehabilitation Medicine, Fukui University Faculty of Medical Sciences, Fukui, Japan. kuchida@u-fukui.ac.jp
Nakajima
Hideaki
H
Yayama
Takafumi
T
Kobayashi
Shigeru
S
Shimada
Seiichiro
S
Tsuchida
Tatsuro
T
Okazawa
Hidehiko
H
Mwaka
Erisa
E
Baba
Hisatoshi
H
D000368:Aged; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology*; D019299:Decompression, Surgical / Q000379:methods; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011859:Radiography; D013116:Spinal Cord / Q000000981:diagnostic imaging / Q000473:pathology*; D013117:Spinal Cord Compression / Q000601:surgery*; D016896:Treatment Outcome
D019788:Fluorodeoxyglucose F18