Early Draining Vein Occlusion After Gamma Knife Surgery for Arteriovenous Malformations

Abstract

Although venous structures are considered more radioresistant, endothelial damage accompanied by venous flow stasis might cause early venous thrombosis and premature venous occlusion after radiosurgery for AVMs. In our series, all patients had a favorable outcome except 1 with a fatal hemorrhage.

Acute Onset of Hemiparesis After Gamma Knife Radiosurgery for Arteriovenous Malformation Caused by Hyperacute Thrombosis of Draining Vein: A Case Report

“…The early draining vein occlusion has been documented to occur at a range of 6.1 to 24.9 months (median, 11.6 months) after GKRS. 4 The shortest time gap between GKRS and occlusion of draining vein occlusion so far was reported by Celix et al, who reported a hemorrhage after GKRS after thrombus in the primary draining vein within 9 days after radiosurgery. 7 In the present case, our patient developed a neurologic deficit in 24 hours after GKRS because of thrombosis of the draining vein, which has not been reported previously in literature.…”

“…Most commonly, the obliteration process starts in the nidus and feeding arteries, and the draining veins close at the end. 4 It was considered that veins are more resistant to radiosurgery, as seen by poor response of venous angioma obliteration to radiosurgery. 5 However, Pollock described the interesting phenomenon of occlusive hyperemia wherein occlusion of draining vein occurred because of radiosurgery before the obliteration of AVM, which can lead to raised intracranial pressure, hemorrhage, or fresh neurologic deficits.…”

“…6 The pathophysiology of draining vein occlusion after radiosurgery was considered to be attributable to various causes, namely direct radiation damage of the draining veins and resultant thrombosis and occlusion of the vein. 4 Pollock et al postulated that radiation-induced changes of the brain resulted in a local pressure increase that caused impaired venous microcirculation. This stagnant blood flow could produce clot formation and involve the larger veins, resulting in thrombosis.…”

Use of Cone-Beam Computed Tomography Angiography in Planning for Gamma Knife Radiosurgery for Arteriovenous Malformations

“…Furthermore, although standard treatment of AVMs in both the surgical and radiosurgery arenas tend to advise sparing the draining vein, previous series with SRS to AVMs have not had as detailed visualization of draining veins as in our series, and it may be that in previous treatment plans the draining veins may have received an increased radiation dose compared to our treatments. Multiple series 51-54 have reported on patients developing radiation-induced changes surrounding the treated nidus and a concurrent thrombosis of the draining vein or veins. In these series, the majority of patients had a favorable outcome implying that some radiation to the draining veins may eventually help with AVM obliteration.…”

Spontaneous thrombosis of the main draining vein revealing an unruptured brain arteriovenous malformation

“…We did not use liquid embolic agent such as Onyx (eV3/Covidien, Irvine, CA) due to the eloquent location of the bAVM and due to the estimated risk of migration of the embolic agent into normal cortical branches related to reflux. We think that both corticosteroids 17 and embolization triggered the reduction of the edema and avoided the bleeding of the malformation.…”