Association of Post-irradiation Temporal Lobe Necrosis and Extra-cranial Carotid Stenosis in Nasopharyngeal Carcinoma

WWM Lam, SF Leung, KH Liu, KS Wong

Hong Kong J Radiol 2003;6:81-5

Aim: To ascertain whether temporal lobe necrosis and extracranial carotid stenosis as long-term complications of radiation are associated.

Patients and Methods: Ninety two patients underwent colour doppler ultrasound examinations for the assessment of carotid artery and cross sectional imaging of the brain. The presence of extracranial carotid stenosis was correlated with the presence of temporal lobe necrosis.

Results: Sixty three patients had carotid artery stenosis (87 common carotid arteries and 65 internal carotid arteries). Twenty patients had temporal lobe necrosis diagnosed by computed tomography or magnetic resonance imaging. The 2 complications were associated (p = 0.072). When extracranial carotid stenosis is used to predict the presence of temporal lobe necrosis, the positive predictive value, negative predictive value, sensitivity, specificity, and accuracy were 27.0%, 89.7%, 85.0%. 36.1%, and 46.7%, respectively.

Conclusion: The presence of extracranial carotid stenosis is not a reliable test to predict the presence of temporal lobe necrosis, but the absence of this complication makes the presence of temporal lobe necrosis unlikely.