[Magnetic resonance imaging manifestations of radiation injury in brain stem and cervical spinal cord of nasopharyngeal carcinoma patients after radiotherapy].
OBJECTIVE
It is very important to diagnose the radiation injury in brain stem and cervical spinal cord of patients with nasopharyngeal carcinoma (NPC) after radiotherapy. Magnetic resonance imaging (MRI) manifestations of radiation encephalopathy have been widely reported, while those of radiation injury in brain stem and cervical spinal cord have been seldom reported. This study was to analyze the MRI characteristics of radiation injury in brain stem and cervical spinal cord of patients with NPC after radiotherapy.


METHODS
MRI was performed in 60 NPC patients 6 months to 5 years after radiotherapy. The imaging sequences included T(1)-weighted image (T(1)WI), T2-weighted image (T(2)WI), fluid attenuated inversion recovery (FLAIR). All patients received T(1)WI contrast-enhanced scanning.


RESULTS
Of the 60 patients, 6 had lesions in cervical spinal cord, 54 had lesions in brain stem. Of the 54 cases of radiation injury in brain stem, most lesions located in pons (20 cases), basis pons and medulla oblongata (26 cases), others located in mesencephalon (3 cases), medulla oblongata (5 cases). All lesions showed hypo- or iso-intense signal on T(1)WI, and hyper-intense signal on T(2)WI. After contrast-enhanced scanning, 11 cases (18.3%) had no enhancement; 49 (81.7%) markedly enhanced with 21 cases (42.9%) of homogenous patchy enhancement, and 28 cases (57.1%) of hetergenerous ringed and patchy enhancement.


CONCLUSIONS
MRI shows clearly the radiation injury in brain stem and cervical spinal cord of NPC patients after radiotherapy.
Song
Ting
T
Department of Radiology, The Second Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, 510120, P.R.China. gzflair@21cn.com
Liang
Bi-Ling
BL
Huang
Sui-Qiao
SQ
Xie
Bang-Kun
BK
Ding
Zhong-Xiang
ZX
Shen
Jun
J
D000328:Adult; D000368:Aged; D001933:Brain Stem / Q000473:pathology / Q000528:radiation effects*; D002574:Cervical Vertebrae; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy*; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000175:diagnosis*; D011878:Radiotherapy / Q000009:adverse effects*; D012189:Retrospective Studies; D013116:Spinal Cord / Q000473:pathology / Q000528:radiation effects*