Thalamic Arteriovenous Malformations Research Articles

Endovascular embolization for basal ganglia and thalamic arteriovenous malformations.

Basal ganglia and thalamic arteriovenous malformations (AVMs) represent a special subset of malformations. Due to the involvement of vital brain structures and the specifically fine and delicate angioarchitecture of these lesions, it presents unique therapeutic challenges and technical difficulties that require thorough treatment planning, individualized treatment strategies, and advanced techniques for good clinical outcome. In this study, we presented a series of ruptured basal ganglia and thalamic AVMs embolized via a transarterial, transvenous or combined approach. Herein, we summarized our treatment experience and clinical outcomes to further evaluate the effectiveness and safety of endovascular embolization for these AVMs as well as the indications, therapy strategies, and techniques of embolization procedures. Twelve patients with basal ganglia and thalamus AVMs were included in the study. Their average age was 23.83 ± 16.51 years (range, 4-57 years) with a female predominance of 67% at presentation. The AVMs were located in the thalamus in 3 (25%) patients, in the basal ganglia in 3 (25%) patients, and in both sites of the brain in 6 (50%) patients. There were 5 AVMs located on the left side and 7 on the right. The mean nidus diameter was 3.32 ± 1.43 cm (range 1.3-6.1 cm). According to the Spetzler-Martin grading classification, 4 (33.3%) brain AVMs were Grade III, 7 (58.3%) were Grade IV, and 1 (8.3%) was Grade V. All of them presented with bleeding at admission: four of these patients presented with an intracerebral hemorrhage (ICH), 8 ICH in combination with intraventricular hemorrhage (IVH), and no patient with subarachnoid hemorrhage (SAH). Among these patients treated with endovascular embolization, 7 patients were treated by the transarterial approach, 4 patients transvenous approach, and 1 patient underwent the combined approach. A single embolization procedure was performed in 6 patients (50%) and the other 6 cases (50%) were treated in a staged manner with up to three procedures. Procedure-related complications occurred only in two patient (16.7%). Complete AVM obliteration was obtained in 7 patients (58.3%), and partial obliteration was in 4 patients (33.3%). Overall, good or excellent outcomes were obtained in 7 patients (58.3%), and poor functional outcome was observed in 5 patients (41.7%) at the last follow-up. All survived patients achieved anatomic stabilization and there was no postoperative bleeding or recurrence in the follow-up. The management of the basal ganglia and thalamic AVMs is a great challenge, which needs multimodal individualized treatment to improve the chances of radiographic cure and good outcomes. Endovascular therapy is safe and effective in the treatment of cerebral AVMs particularly for deep-seated AVMs such as the basal ganglia and thalamus. Our results demonstrate a high rate of anatomic obliteration with an acceptable rate of complications in the endovascular treatment of these vasculopathies via a transarterial approach or a transvenous approach.

Embolization of midbrain arteriovenous malformation fed by the artery of Percheron in a child, the first case report and literature review.

Artery of Percheron (AOP) as main feeder artery of arteriovenous malformation (AVM) is extremely rare. Two cases of thalamic AVM fed by AOP have been reported to date and only one AVM been removed by microsurgery when attempt of intervention embolization failed. Midbrain AVM fed by AOP has not been reported yet. Here, we presented the first successful embolized case of midbrain AVM supplied by the AOP in a 10-year-old boy, who suffered dual oculomotor nerve palsy and secondary hemorrhage before embolization. During endovascular embolization, selective angiography by 1.2 Fr. Magic microcatheter showed an intranidal aneurysm located on the distal AOP. Two injections of a 1:4 ratio mixture of NBCA-MS completely occlude the nidus and intranidal aneurysm with no complications occurred. The child recovered well and the oculomotor deficits improved. This case highlighted that AOP is a clinically significant branch associated with AVM in midbrain and thalamus. Moreover, intervention embolization of midbrain AVM fed by AOP is a considerable therapeutic strategy.

Gamma Knife Radiosurgery for Central Arteriovenous Malformations— A Single-Center Experience

Introduction: Arteriovenous malformations with basal ganglia, brainstem, and thalamic locations represent difficult vessel anomalies with critical locations. These central aneurysms are related with high morbidity and mortality rates. This retrospective study aims to examine the results of patients with basal ganglia, brainstem, and thalamic arteriovenous malformations remedied with gamma knife radiosurgery (GKS) at our clinic.
 Method: May 2005 - December 2020, the results of patients with GKS basal ganglia, thalamus, and brainstem located AVM were analyzed, in Gazi University Gamma Knife Unit.
 Results: May 2005 - December 2020, a total of 859 patients with intracranial AVM were treated at the Gamma Knife Unit of the Gazi University Neurosurgery Clinic. Seventy-three patients with basal ganglia, brainstem, and thalamic locations were seen. Of the total 73 patients included in our study, 14 patients (19.2%) in the basal ganglia, 13 patients (17.8) in the brain stem, and 46 patients (63%) in the thalamic region were located. The mean volume of AVMs is 4565,54 mm3. The patients who underwent embolization before gamma knife surgery treatment were found to be 19.2%. The mean of AVMs' obliteration time after SRS is 38.4 months. We detected that there wasn't a remarkable statistical rate relationship between AVMs volume, Spetzler Martin grading scale, nidus type, gender, and prior embolization (p = 0.05).
 Conclusions: GKS is an best choice treatment method used for all AVMs today. However, it has been accepted as the first choice treatment method, especially in central AVMs, which are risky in terms of mortality and morbidity, and the results are also quite good.

Aneurysmal dilatation of vein of galen associated with thalamic arteriovenous malformation and straight sinus agenesis

Straight sinus agenesis is a rare congenital anatomical variation that is usually accompanied by persistent falcine sinus. Concomitance of straight sinus agenesis and absence of falcine sinus are associated with thalamic arteriovenous malformation by the disturbance of the venous flow. In this report, a very rare case of aneurysmal dilatation of the vein of Galen associated with thalamic arteriovenous malformation and straight sinus agenesis is presented.

Coil migration during pressure-cooker technique for cerebral AVM

Introduction: In recent decades, the endovascular treatment of cerebral arteriovenous malformations (AVMs) has advanced. However, it still carries risks of unanticipated complications. Coil migration is a reported complication of aneurysmal coiling procedures. Herein, we report a case of early intraprocedural coil migration during pressure cooker technique embolization of right thalamic AVM, discussing the management and potential explanations. The literature showed no report of coil migration after the pressure cooker technique in the form of coil-augmented Onyx injection technique (CAIT). Case description: An otherwise healthy 26-year-old female suddenly developed a severe headache with no loss of consciousness. Computed tomography (CT) scan of the head illustrated intraventricular haemorrhage. Magnetic resonance imaging (MRI) showed the bag of worms' sign in the right thalamic area. The size and location of the AVM prompted the decision for multistage endovascular embolization using onyx. In the anterior circulation, the right A5 arterial feeder has a high flow which indicates the pressure cooker technique embolization in the form of CAIT. In the procedure, early detachment and migration of the coil occurred in the medial prefrontal branch through the anterior cerebral artery. No intervention to retrieve the coil was carried out because the detachment piece is small and lodged distally. Onyx was injected directly without the coil because of the risk of radiation to the patient. Otherwise, the intraprocedural and postprocedural courses went uneventful. Conclusion: This is the first report of coil migration during the pressure cooker technique with CAIT for the right thalamic AVM.

The Thalamic Arteriovenous Malformations Have Better Prognosis than Basal Ganglia Malformations Regarding Obliteration: Prognostic Factors Analysis

Arteriovenous malformations (AVMs) are rare vascular congenital lesions that affect mainly patients during their productive years of life. In order to obtain a better quality of life for patients with this disease, a multidisciplinary approach is recommended. Radiosurgery is one of the treatment modalities available for AVMs, but many factors may influence the effectiveness of this strategy. Classically, it has been said that deep-seated lesions have a particular behavior compared with AVMs in other regions, but a differentiation between thalamic lesions and those located in the basal ganglia has not been made. Institutional records for central core AVMs treated with radiosurgery between January 2004 and January 2014 were retrospectively analyzed. Brainstem lesions were excluded from the analysis. Forty-nine patients with deep-seated AVMs were included. Forty-three (87.8%) were located in the thalamus and 6 (12.2%) in the area of basal ganglia. The nidus mean volume was 4.1 cm3 (SD:4.1), the maximum diameter mean was of 19.5 mm (SD:8.0). The prescription dose was 18.2 Gy (SD:2.1), and the follow-up time was 75.8 months (SD:32.5). There was a greater obliteration rate in thalamic AVMs compared with those located in the basal ganglia: 81.4% versus 33.3% (P= 0.026), respectively. There was no association between categorical variables and obliteration rate. Stereotactic radiosurgery is a good option for patients with thalamic and basal ganglia AVMs, but a multidisciplinary approach to decision-making is mandatory in order to achieve the best results.

Multimodal management of arteriovenous malformations of the basal ganglia and thalamus: factors affecting obliteration and outcome.

Arteriovenous malformations (AVMs) of the basal ganglia and thalamus are particularly difficult lesions to treat, accounting for 3%-13% of all AVMs in surgical series and 23%-44% of malformations in radiosurgery series. The goal of this study was to report the results of multimodal management of basal ganglia and thalamic AVMs and investigate the factors that influence radiographic cure and good clinical outcomes. This study was a retrospective analysis of a prospectively maintained database of all patients treated at the authors' institution. Clinical, radiological, follow-up, and outcome data were analyzed. Univariate and multivariate analyses were conducted to explore the influence of various factors on outcome. The results and data analysis pertaining to 123 patients treated over 32 years are presented. In this cohort, radiographic cure was achieved in 50.9% of the patients. Seventy-five percent of patients had good clinical outcomes (stable or improved performance scores), whereas 25% worsened after treatment. Inclusion of surgery and radiosurgery independently predicted obliteration, whereas nidus diameter and volume predicted clinical outcomes. Nidus volume/diameter and inclusion of surgery predicted the optimal outcome, i.e., good clinical outcomes with lesion obliteration. Good outcomes are possible with multimodal treatment in these complex patients. Increasing size and, by extension, higher Spetzler-Martin grade are associated with worse outcomes. Inclusion of multiple modalities of treatment as indicated could improve the chances of radiographic cure and good outcomes.

WITHDRAWN: Multimodal treatment and microsurgical resection of basal ganglionic and thalamic arteriovenous malformations

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Arteriovenous Malformation in a Youth with Atypical Autism Symptoms.

Cerebral arteriovenous malformations (AVMs) present a challenge to diagnose in children with developmental disability, because of the overlap in behavioral symptoms and neurologic manifestations. They have been very rarely reported in conjunction with autism spectrum disorder. This case involves a 13 year old male with a history of autism spectrum disorder and significant behavioral issues diagnosed with a thalamic AVM following lateralizing neurologic symptoms. Despite radiosurgical treatment, hemorrhage followed consequently causing extensive neurologic injury and death. This case emphasizes the need for close follow up and coordination within a medical home for children with developmental disabilities. A multidisciplinary team approach is ideal to allow detection of subtle neurologic changes over time that may be masked as behavioral difficulties.

Thalamic arteriovenous malformation fed by the artery of Percheron originating from the contralateral posterior cerebral artery in a child

Artery of Percheron (AOP) is a rare variant of thalamoperforating artery with a single common trunk feeding both thalami and with or without contribution to the rostral midbrain. We report the first case of thalamic arteriovenous malformation (AVM) fed by AOP with hemorrhagic onset. A 12-month-old girl suddenly weakened and developed coma. Left thalamic hemorrhage was detected with the third and both lateral ventricles' hematoma. Thalamic AVM was discovered to be fed by an AOP originating from the contralateral posterior cerebral artery. Endovascular embolization of AVM was impossible due to a risk of bilateral thalamic infarction and anatomical inaccessibility. Thalamic AVM was removed by high superior parietal approach without new neurological symptoms. The first case of thalamic AVM fed by AOP originating from the contralateral posterior cerebral artery is reported. Surgical removal of AVM would be at the heart of treatment in order to avoid bilateral thalamic infarction.

Hypofractionated Stereotactic Radiosurgery in a Large Bilateral Thalamic and Basal Ganglia Arteriovenous Malformation

Purpose. Arteriovenous malformations (AVMs) in the basal ganglia and thalamus have a more aggressive natural history with a higher morbidity and mortality than AVMs in other locations. Optimal treatment—complete obliteration without new neurological deficits—is often challenging. We present a patient with a large bilateral basal ganglia and thalamic AVM successfully treated with hypofractionated stereotactic radiosurgery (HFSRS) with intensity modulated radiotherapy (IMRT). Methods. The patient was treated with hypofractionated stereotactic radiosurgery to 30 Gy at margin in 5 fractions of 9 static fields with a minimultileaf collimator and intensity modulated radiotherapy. Results. At 10 months following treatment, digital subtraction angiography showed complete obliteration of the AVM. Conclusions. Large bilateral thalamic and basal ganglia AVMs can be successfully treated with complete obliteration by HFSRS with IMRT with relatively limited toxicity. Appropriate caution is recommended.

Junctional Visual Field Loss in a Case of Wyburn-Mason Syndrome

A previously healthy girl failed a routine eye screening at the age of 6 years. Her visual fields showed generalized depression in the right eye and a superotemporal defect in the left eye, consistent with a junctional scotoma. Funduscopic examination and fluorescein angiography revealed markedly dilated tortuous vascular loops with arteriovenous communications consistent with retinal arteriovenous malformations (AVMs). MRI of the brain and cerebral angiography demonstrated right ophthalmic and right thalamic AVMs, with compression and atrophy of the right optic chiasm. This represents a case of Wyburn-Mason syndrome with a junctional scotoma.

Editorial: Radiosurgery and deep arteriovenous malformations

Cheng et al.1 present the results of Gamma Knife surgery, collected over 3 decades, in 182 patients with basal ganglia (85) and thalamic (97) arteriovenous malformations (AVMs) followed up for more than 2 years. The mean nidus volume was 3.4 cm3 (range <1 to 29 cm3), and the mean margin dose was 21 Gy (range 10–28 Gy). Half of the AVMs were angiographically obliterated after a single GKS treatment, and roughly one-third of those retreated were angiographically obliterated, giving an overall definitive cure rate of 58%. If one includes MR imaging–suspected obliterations, the rate is about 66%, and if one includes lesions with only a residual venous shunt, the rate is close to 75%, but the authors rightly caution against doing so. These results were achieved at the cost of a 10% incidence of symptomatic radiationrelated necrosis and a 5% incidence of permanent new deficits related to radiation effect. As expected, predictors of angiographically confirmed obliteration were as follows: small lesion size, favorable shape (a surrogate for fewer isocenters), high margin dose, and no prior embolization. In a multivariate analysis, the only predictor of permanent deficits was unruptured status. Despite the fact that 76% of the lesions had previously bled and more than 98% were symptomatic, only 2 hemorrhages were noted in the posttreatment period (both cases fatal), and only 3 patients had symptoms progression. If one adds these patients, the overall morbidity rate was 7.5% and the mortality rate was 1.0% (8.5% combined). Given that 23% of the lesions were Spetzler-Martin Grade IV or V, 93% were Grade III or worse, and 31% had failed prior surgery or embolization, the results seem quite laudable. The authors conclude that in young patients with ruptured basal ganglia/thalamic AVMs in whom microsurgery is thought to pose a high risk by an experienced surgeon, radiosurgery is a reasonable alternative. I would concur, but ask a simple question: what is the definition of “experienced” when it comes to microsurgical treatment of basal ganglia and thalamic AVMs? I suspect that even busy surgeons in large cerebrovascular referral centers will not operate on more than 1 or 2 of these lesions a year and that surgeons associated with even the busiest radiosurgical units may operate on no more than 5 in a lifetime. Therefore, I suspect the truth, in most practice settings, is actually the reverse of what Cheng and colleagues propose. The first question asked is not, “Is this basal ganglia/thalamic AVM good for an ‘experienced microsurgeon?’” but rather, “Is it small enough and round enough that we’ll be able to get 20 Gy on the margin without causing a major radiation-induced deficit, and, if not, can we shrink the lesion with embolization to get it to that size and potentially obliterate the bleed site at the same time?” The data presented here do not necessarily invalidate this real-world approach, but they do not give us as much guidance as we’d like. For example, while there was a lower obliteration rate in the 38 patients treated with preradiosurgical embolic agents, the hemorrhage rate was far lower than what natural history studies would predict, given that 42% of patients were incompletely protected. Future prospective multicenter efforts will be needed if we are to ever really understand what is the best treatment for lesions so heterogeneous and rare, especially when the treatments are so dependent on user skill and experience and ongoing technological improvements. (http://thejns.org/doi/abs/10.3171/2011.10.JNS111419)

Gamma Knife surgery for basal ganglia and thalamic arteriovenous malformations

Gamma Knife surgery (GKS) has emerged as the treatment of choice for small- to medium-sized cerebral arteriovenous malformations (AVMs) in deep locations. The present study aims to investigate the outcomes of GKS for AVMs in the basal ganglia and thalamus. Between 1989 and 2007, 85 patients with AVMs in the basal ganglia and 97 in the thalamus underwent GKS and were followed up for more than 2 years. The nidus volumes ranged from 0.1 to 29.4 cm(3) (mean 3.4 cm(3)). The mean margin dose at the initial GKS was 21.3 Gy (range 10-28 Gy). Thirty-six patients underwent repeat GKS for residual AVMs at a median 4 years after initial GKS. The mean margin dose at repeat GKS was 21.1 Gy (range 7.5-27 Gy). Following a single GKS, total obliteration of the nidus was confirmed on angiograms in 91 patients (50%). In 12 patients (6.6%) a subtotal obliteration was achieved. No flow voids were observed on MR imaging in 14 patients (7.7%). Following single or repeat GKS, total obliteration was angiographically confirmed in 106 patients (58.2%) and subtotal obliteration in 8 patients (4.4%). No flow voids on MR imaging were observed in 18 patients (9.9%). The overall obliteration rates following one or multiple GKSs based on MR imaging or angiography was 68%. A small nidus volume, high margin dose, low number of isocenters, and no history of embolization were significantly associated with an increased rate of obliteration. Twenty-one patients experienced 25 episodes of hemorrhage in 850 risk-years following GKS, yielding an annual hemorrhage rate of 2.9%. Four patients died in this series: 2 due to complications of hemorrhage and 2 due to unrelated diseases. Permanent neurological deficits caused by radiation were noted in 9 patients (4.9%). Gamma Knife surgery offers a reasonable chance of obliterating basal ganglia and thalamic AVMs and does so with a low risk of complications. It is an optimal treatment option in patients for whom the anticipated risk of microsurgery is too high.

The Impact of Microscope-Integrated Intraoperative Near-Infrared Indocyanine Green Videoangiography on Surgery of Arteriovenous Malformations and Dural Arteriovenous Fistulae

Microscope-based intraoperative near-infrared indocyanine green (ICG) videoangiography is useful as an adjunct to intra- or postoperative digital subtraction angiography (DSA) in aneurysm surgery. To evaluate intraoperative ICG videoangiography for surgery of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (dAVFs). Seventeen patients undergoing surgical resection of intracranial AVM or AVF were enrolled into this prospective evaluation. ICG videoangiography sequences were analyzed with regard to transit times to differentiate between arterial, early venous, capillary, and venous phase as well as early passage (fistula) and delayed appearance (ischemia). ICG videoangiography was compared with pre- and postoperative angiography. Forty-six ICG videoangiographies were performed in 17 operative procedures. In 41 ICG investigations image quality and spatial resolution were excellent to analyze arterial, early venous, capillary, and venous phase. In 2 cases ICG videoangiography provided additional information to change the surgical strategy. With the exception of one case only, the postoperative angiogram corresponded to the last ICG examination performed after the resection. No side effects related to ICG injection were observed. In one patient with a deep thalamic AVM the final ICG investigation was inconclusive owing to insufficient illumination of the deep surgical field. Microscope-integrated repetitive ICG videoangiography during AVM and dAVF surgery is fast, easy to perform, and safe. This simple and safe real-time method is a useful additional tool that can potentially lower the surgical risk in complex AVMs and help avoid missed residuals.

Dystonic Tremor as a Presenting Symptom of a Thalamic Arteriovenous Malformation: Case Report and Review

Dystonic Tremor as a Presenting Symptom of a Thalamic Arteriovenous Malformation: Case Report and Review

Illuminations

HomeRadioGraphicsVol. 29, No. 5 PreviousNext IlluminationsFree AccessDanger Lies AheadKai-hung FungKai-hung FungAuthor AffiliationsHong Kong, ChinaKai-hung FungPublished Online:Sep 1 2009https://doi.org/10.1148/radiographics.29.5.10.1148_027153330290051332MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked InEmail With rainbow rendering of computed tomographic data, exploration inside the cranium is simultaneously bedazzling and ominous. In a view toward the vertex, the superior sagittal sinus appears as a large, gentle C-curve. But the center of the surreal “landscape” seems dominated by the venous varix and draining vein of a thalamic arteriovenous malformation, which throb in orange above a mass of luminous tentacles, representing the basilar artery and bilateral internal carotid arteries (lower left).Download as PowerPointOpen in Image Viewer Article HistoryPublished in print: Sept 2009 FiguresReferencesRelatedDetailsRecommended Articles Radiologic Clues to Cerebral Venous ThrombosisRadioGraphics2019Volume: 39Issue: 6pp. 1611-1628Acute Headache in the Emergency SettingRadioGraphics2019Volume: 39Issue: 6pp. 1739-1759Intracranial Arteriovenous Malformation: Cinematic Rendering with Digital Subtraction AngiographyRadiology2019Volume: 294Issue: 3pp. 506Imaging of Neurologic Conditions in Pregnant PatientsRadioGraphics2016Volume: 36Issue: 7pp. 2102-2122Clinical-Radiologic Correlation of Extraocular Eye Movement Disorders: Seeing beneath the SurfaceRadioGraphics2016Volume: 36Issue: 7pp. 2123-2139See More RSNA Education Exhibits Keep an Eye Peeled: Imaging Findings in Vascular Causes of Visual DisturbanceDigital Posters2020Stroke in Pediatric Age Group: How MRI Can Help?Digital Posters2018Cervical and Intracranial Neurovascular Devices: What the Neuroradiologist Needs to KnowDigital Posters2020 RSNA Case Collection Cavernous internal carotid artery pseudoaneurysmRSNA Case Collection2021Carotid paragangliomaRSNA Case Collection2020Superior sagittal sinus thrombosisRSNA Case Collection2022 Vol. 29, No. 5 Metrics Downloaded 827 times Altmetric Score

Transvenous Embolization of a Symptomatic Venous Aneurysm Developing in the Drainage Network of a Deep Cerebral AVM: A Case Report

We present a case of a symptomatic venous aneurysm that developed in the drainage network of a deep-seated basal ganglia and thalamic arteriovenous malformation. The venous aneurysm was treated selectively with platinum coils using a venous approach.

A case report of Wyburn-Mason syndrome and review of the literature

Wyburn-Mason syndrome is a distinct congenital neurocutaneous entity comprised of ipsilateral arteriovenous malformations (AVMs) of the midbrain, vascular abnormalities affecting the visual pathway, and facial nevi. We report a case and review of the literature of all other reported cases of Wyburn-Mason syndrome (n = 26) in the English literature since 1973. In this review, we report on a 4(1/2)-year-old boy with Wyburn-Mason syndrome who presented with left retinal and orbital AVMs and a ruptured thalamic AVM. The patient did not respond to light in the left eye and demonstrated a left afferent pupillary defect. He did not have any cutaneous lesions. We also characterize other reported cases of Wyburn-Mason syndrome. The presentation of patients with Wyburn-Mason syndrome can vary greatly according to the site and the extent of vascular lesions. Intracranial AVMs occasionally hemorrhage with significant morbidity. Treatment is controversial, and patients are typically managed conservatively by observation.

Recurrent late cerebral necrosis with aggressive characteristics after radiosurgical treatment of an arteriovenous malformation

/Late cerebral radiation necrosis usually occurs within 3 years of stereotactic radiosurgery. The authors report on a case of recurrent radiation necrosis with rapid clinical deterioration and imaging findings resembling those of a malignant glioma. This 68-year-old man, who had a history of a left posterior temporal and thalamic arteriovenous malformation (AVM) treated with linear accelerator radiosurgery 13 years before presentation and complicated by radiation necrosis 11 years before presentation, exhibited new-onset mixed aphasia, right hemiparesis, and right hemineglect. Imaging studies demonstrated hemorrhage and an enlarging, heterogeneously enhancing mass in the region of the previously treated AVM. The patient was treated medically with corticosteroid agents, and stabilized temporarily. Unfortunately, his condition worsened precipitously soon thereafter, requiring the placement of a shunt for relief of obstructive hydrocephalus. Further surgical intervention was offered, but the patient's family opted for hospice care instead. The patient died 10 weeks after initially presenting to the authors' institution, and the results of an autopsy demonstrated radiation necrosis. Symptomatic radiation necrosis can occur more than a decade after stereotactic radiosurgery, necessitating patient follow up during a longer period of time than currently practiced. Furthermore, there is a need for more careful reporting on the natural history of such cases to clarify the pathogenesis of very late and recurrent radiation necrosis after radiosurgery and to define patient groups with a higher risk for these entities.