Radiation-induced cerebrovasculopathy of the distal middle cerebral artery and distal posterior cerebral artery--case report

Middle cerebral artery stenosis in patients with nasopharyngeal carcinoma after radiotherapy: the incidence of stenosis and the risk factors

OBJECTIVE

The purpose of the present study was to investigate the incidence of middle cerebral artery (MCA) stenosis by contrast-enhanced MR angiography (CE-MRA), and to evaluate the risk factors for significant (>50%) MCA stenosis in patients with nasopharyngeal carcinoma (NPC) after radiotherapy.

METHODS

116 patients with NPC after radiotherapy were recruited into the irradiation group to investigate the incidence and degree of MCA stenosis by CE-MRA. The results were compared with those of the control group, which comprised 57 newly diagnosed patients with NPC who did not receive radiotherapy. Furthermore, the risk factors for significant MCA stenosis were evaluated.

RESULTS

There was a higher incidence of MCA stenosis in the irradiation group than in the control group in terms of patient number (p = 0.000) and vessel involvement (p = 0.000), respectively. The incidence of significant MCA stenosis in the irradiation group was 8.6% (10/116 patients) and 5.2% (12/232 patients) in terms of patient number and vessel involvement, respectively. However, no significant MCA stenosis was found in the control group. Univariate analysis showed that hypercholesterolaemia, T(3-4) stage and longer time interval from radiotherapy were the risk factors related to significant MCA stenosis. Multivariate analysis demonstrated that only T stage was the independent risk factor for significant MCA stenosis development.

CONCLUSION

The results showed that radiation can cause MCA stenosis in patients with NPC after radiotherapy, especially in those with T(3-4) stage, and further study is needed.

ADVANCES IN KNOWLEDGE

Radiation-induced MCA stenosis exists in patients with NPC after radiotherapy, and its prevalence is more common in patients with clinical T(3-4) stage.

Radiation-induced moyamoya disease after childhood astrocytoma

Adjunctive radiation treatment of childhood intracranial neoplasms of grade II or higher creates a risk of subsequent vasculopathy. A 28-year-old male presented with a Glasgow Coma Scale 12 after acute collapse and hemiparesis with an intraparenchymal haematoma. Emergent craniotomy, histopathology and subsequent imaging confirmed the cause as radiation-induced moyamoya disease, subsequent to treatment for a grade 2 astrocytoma 24 years previously. He had been lost to follow-up after normal serial imaging performed up to 10 years after his initial diagnosis. Long term surveillance imaging may be of benefit in identifying treatable vascular anomalies.

Vascular complications of cranial radiation

OBJECTIVES

Cerebral vascular disease has been reported as a long-term complication of cranial radiotherapy. The purpose of this study was to examine the frequency and risk factors associated with development of cerebral vascular disease in children after cranial radiation.

MATERIALS AND METHODS

A retrospective chart review of all cancer patients treated between 1985 and 2003 who were under the age of 18 years at the time of initial radiotherapy was performed. Variables examined include diagnosis and site of malignancy, age at the time of radiotherapy, sex, total radiation dosage, number of fractions, duration, and whether the patient had proven cerebral vascular event.

RESULTS

Two hundred and forty-four patients met the study criteria. One hundred and 13 cases involved tumors of the central nervous system. The remaining patients had systemic neoplastic disease. Post radiation cerebral vascular disease occurred in 11 (5%) patients, and all but one patient had a tumor involving the central nervous system (mainly in the posterior fossa and supratentorial midline).

CONCLUSION

There is an increased risk of cerebral vascular disease after radiation therapy in childhood, especially in children who received high dose radiation at the posterior fossa and supratentorial axial region.