Stereotactic radiosurgery as a feasible treatment for intramedullary spinal arteriovenous malformations: a single-center observation

Abstract

Spinal cord intramedullary arteriovenous malformations are rare. For patients suffering from either hemorrhage or myelopathy, surgical or endovascular interventions are indicated. However, complete eradication of the nidus is often difficult because of its intramedullary location and complex angioarchitecture. In this report, we evaluate the feasibility and safety of stereotactic radiosurgery as a treatment modality for intramedullary spinal arteriovenous malformations (AVMs). Between 2010 and 2014, we performed stereotactic radiosurgery to treat four patients with intramedullary AVM and one with spinal arteriovenous metameric syndrome (one woman and four men; age range, 31-66 years). Three patients presented with myelopathy, and two suffered hemorrhages. Nidi were located in the cervical (three cases) and thoracic (two cases) spinal cord regions. Based on the angioarchitecture, surgery and endovascular embolization were indicated. When both modalities were deemed hazardous, radiosurgery using CyberKnife™ was offered. Radiation using marginal doses of 18 Gy was administered in three fractions. The mean follow-up period was 37.2 months (range, 16-62 months). After treatment, two of the three patients with myelopathy experienced either improvement or stabilization of their symptoms and one experienced worsening of dysesthesia. In two patients with hemorrhage, symptoms improved in one and remained stable in the other. No further hemorrhagic episodes were evident during follow-up. Follow-up angiograms showed marked shrinkage of the nidus located in the thoracic spinal cord in one case and angiographic stabilization in the others. As a treatment modality for intramedullary AVMs, CyberKnife™ is safe and can be considered when surgery or endovascular therapy is not indicated. To determine optimum radiation doses and protocols for treating spinal AVMs, further studies with more patients and long-term follow-up are required.

Ruptured Spinal Arteriovenous Malformation: A Rare Cause of Paraplegia in Pregnancy

“…A recent article published in 2017 by Rashad and colleagues in Neurosurgical Review described a novel method for treating intramedullary AVMs using stereotactic radiosurgery [ 10 ]. Of note, this technique was used in two patients who had suffered haemorrhages and were not suitable for surgery or embolisation.…”

Stereotactic Radiotherapy for Intramedullary Spinal Arteriovenous Malformations

“…Furthermore, both complete and partial endovascular treatments have been shown to significantly decrease the risks of future hemorrhage [ 3 , 12 ]. SRS/SRT is another possible treatment option for intramedullary spinal AVM, though only a few series have been reported thus far [ 1 , 5 , 7 , 9 - 10 ]. The reported series are summarized in Table 2 .…”

“…He did not show any clinical improvement, probably because he had irreversible damage to the spinal cord. Rashad et al [ 1 ] reported the results in five cases, including one case of a spinal arteriovenous metameric syndrome. They used a lower radiation dose (biological equivalent dose (BED) = 72 Gy) and delivered 18 Gy in three fractions using the CyberKnife.…”

“…Intramedullary spinal cord arteriovenous malformations (AVMs) are rare and challenging to treat. Such lesions usually have multiple feeders that originate from the anterior and/or posterior spinal arteries [ 1 ]. Patients present with intramedullary hemorrhage, subarachnoid hemorrhage, or congestive myelopathy [ 2 - 3 ].…”

“…However, those are performed effectively only when certain conditions are present, such as favorable location, size, and vascular anatomy allowing management [ 4 - 5 ]. Although it has been reported in many papers that cerebral AVMs can be effectively treated by stereotactic radiosurgery (SRS)/stereotactic radiotherapy (SRT) [ 6 ], only a few reports have documented the efficacy of SRS/SRT for spinal intramedullary AVMs [ 1 , 5 , 7 - 10 ]. Herein, we report our experience of treating five patients with symptomatic intramedullary spinal cord AVM by SRT.…”