Stereotactic Gamma Knife Radiosurgery for Extracranial Arteriovenous Malformations

Abstract

Introduction: Head and neck extracranial arteriovenous malformations (AVMs) are rare pathological conditions which pose diagnostic and reconstruction challenges. Stereotactic radiosurgery (SRS) is nowadays an established treatment method for brain AVMs, with high obliteration and low complication rates. Here we describe the first report of head extracranial AVMs successfully treated by Gamma Knife (GK) as a retrospective historical cohort. Methods: Over a 9-year period, 2 cases of extracranial AVMs were treated by GK Perfexion (Elekta Instruments AB, Stockholm, Sweden) at a single institution. A stereotactic frame and multimodal imaging, including digital subtraction angiography (DSA), were used. The prescribed dose was 24 Gy at the 50% isodose line. Results: The first case was of a patient with pulsating tinnitus and left superficial parotido-condylian AVM. Embolization achieved partial obliteration. Tinnitus disappeared during the following 6 months after GK. The second case was a patient with repetitive gingival hemorrhages and right superior maxillary AVM, fed by the right internal maxillary and facial arteries. Embolization achieved partial obliteration with recurrence of symptoms. GK was further performed. DSA confirmed complete obliteration in both patients. Conclusions: Single-fraction GK radiosurgery appears to be safe and effective for extracranial AVMs. We recommend prescribing doses that are comparable to the ones used for brain AVMs (i.e., 24 Gy). A stereotactic frame is an important tool to ensure higher accuracy in the context of these particular locations. However, in selected cases, a mask could be applied either for single fraction purposes (if in a non-mobile location) or for hypofractionation, in case of larger volumes. These findings should be validated in larger cohorts, inclusively in terms of dose prescription.

Lower-Extremity Arteriovenous Malformation Masquerading as Peripheral Artery Disease

“…Treatments include conservative management, pharmacologic trials, transarterial embolization, stereotactic gamma knife radiosurgery, and open surgical resection of the affected tissue [1,7]. Depending on the size, site, and extent of the lesion, the goal of treatments may be the temporary inhibition of AVM progression rather than cure [4,[9][10][11]. Based on the Schobinger scale, stage I AVMs rarely require interventions and can be managed conservatively, stage II AVMs can be considered for invasive management, and stage III/IV AVMs require either embolization or surgical management [8].…”

The addition of adjuvant radiotherapy in the management of extracranial arterio-venous malformations: a case discussion

“…4 Although the role of SBRT in the management of extracranial AVMs has not been established and the published experience is limited, it has been used in head and neck AVMs safely and effectively using similar doses to those used in brain AVMs. [5][6][7] Hereby, we present the case of an AVM located in the metatarsal area of the foot that was successfully eradicated with the use of adjuvant radiotherapy. Prior to the radiotherapy treatment, the patient had undergone one session of embolotherapy followed by staged surgical excisions with immediate microsurgical reconstruction.…”

Stereotactic Body Radiotherapy (SBRT) for an Extracranial Arteriovenous Malformation of the Pelvis

“…Stereotactic radiosurgery, an effective treatment option for intracranial AVMs, is not available for extracranial AVMs because the traditional technique of using a gamma knife device is not possible for targets outside the head. However, hypofractionated stereotactic body radiotherapy (SBRT) has been successfully used in a small number of patients with extracranial AVMs, most with lesions in the head-and-neck region [9][10][11][12].…”