Internal carotid occlusion following gamma knife radiosurgery for cavernous sinus meningioma.
Gamma knife radiosurgery is a safe and effective treatment for cavernous sinus meningioma, associated with a very low morbidity. However, a high dose of radiation could lead to modifications of the vascular wall such as in radiosurgical treatment of arteriovenous malformations. We present a patient treated by gamma knife radiosurgery for a left cavernous sinus meningioma using a margin dose of 13 Gy at the 50% isodose. A complete occlusion of the intracavernous segment of the ICA occurred during the follow-up, in combination with a regression of the meningioma volume. The patient sustained no neurological deficit. We found that a hot spot of dose was administered to the intracavernous segment of the internal carotid artery, with a maximum dose of 22.3 Gy. Dose heterogeneity inside the target volume can produce hot spots of dose inside the internal carotid artery that can lead to a vascular occlusion. Therefore, we recommend shifting the hot spot during the dosimetry planning in order to reduce the incidence of such vascular injury.
Abeloos
Laurence
L
Departement of Neurosurgery, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium. labeloos@ulb.ac.be
Levivier
Marc
M
Devriendt
Daniel
D
Massager
Nicolas
N
D000328:Adult; D002343:Carotid Artery, Internal / Q000473:pathology* / Q000528:radiation effects; D016893:Carotid Stenosis / Q000209:etiology* / Q000473:pathology; D002426:Cavernous Sinus / Q000601:surgery*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008579:Meningioma / Q000601:surgery*; D011832:Radiation Injuries / Q000473:pathology*; D011874:Radiometry; D016634:Radiosurgery / Q000009:adverse effects*