A study of radiation-induced cerebral vascular injury in nasopharyngeal carcinoma patients with radiation-induced temporal lobe necrosis.
OBJECTIVE
To investigate radiation-induced carotid and cerebral vascular injury and its relationship with radiation-induced temporal lobe necrosis in nasopharyngeal carcinoma (NPC) patients.


METHODS
Fifty eight NPC patients with radiation-induced temporal lobe necrosis (TLN) were recruited in the study. Duplex ultrasonography was used to scan bilateral carotid arterials to evaluate the intima-media thickness (IMT) and occurrence of plaque formation. Flow velocities of bilateral middle cerebral arteries (MCAs), internal carotid arteries (ICAs) and basal artery (BA) were estimated through Transcranial Color Doppler (TCD). The results were compared with data from 33 patients who were free from radiation-induced temporal lobe necrosis after radiotherapy and 29 healthy individuals.


RESULTS
Significant differences in IMT, occurrence of plaques of ICAs and flow velocities of both MCAs and ICAs were found between patients after radiotherapy and healthy individuals (p<0.05). IMT had positive correlation with post radiation interval (p = 0.049). Compared with results from patients without radiation-induced TLN, the mean IMT was significantly thicker in patients with TLN (p<0.001). Plaques were more common in patients with TLN than patients without TLN (p = 0.038). In addition, flow velocities of MCAs and ICAs in patients with TLN were much faster (p<0.001, p<0.001). Among patients with unilateral TLN, flow velocity of MCAs was significantly different between ipsilateral and contralateral sides to the lesion (p = 0.001).


CONCLUSIONS
Thickening of IMT, occurrence of plaque formation and hemodynamic abnormality are more common in patients after radiotherapy, especially in those with TLN, compared with healthy individuals.
Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Jianhong
J
Ye
Xiaoming
X
Rong
Yanqun
Y
Xiang
Yigang
Y
Xing
Yamei
Y
Tang
D000328:Adult; D002277:Carcinoma; D020212:Carotid Artery Injuries / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology / Q000528:radiation effects*; D059168:Carotid Intima-Media Thickness; D005260:Female; D006439:Hemodynamics / Q000528:radiation effects; D006801:Humans; D008297:Male; D020768:Middle Cerebral Artery / Q000293:injuries* / Q000473:pathology / Q000503:physiopathology / Q000528:radiation effects; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000532:radiotherapy*; D009336:Necrosis; D011832:Radiation Injuries / Q000473:pathology* / Q000503:physiopathology; D013702:Temporal Lobe / Q000473:pathology* / Q000528:radiation effects*