Cerebral arteriovenous malformations in children

Over the past 10 years (1982–1992), we have been actively involved in the management of 179 cerebral arteriovenous malformations (CAVMs) in children and infants. Seventy-seven were true vein of Galen malformations (VGAMs) and 102 were pial AVMs (PAVMs), i.e., developed in the subpial space. Hemorrhage occurred as the first symptom in 50% of the children with pial AVMs, but was present in none of the VGAM cases. Only 31 children were found to be unsuitable for endovascular treatment, and in 124 cases embolization was indicated as the primary treatment (104 embolization performed). Only 21 children underwent a direct surgical approach (none in the VGAM group). In the embolized group in whom treatment has been completed (n = 56), 8 children died, 39 have an anatomical cure, and 34 are clinically normal. In the group under treatment (n = 56), 16 are not normal. The problems are timing and the aims (total or partial treatment) of the therapeutic procedures. In the nonembolized group (n = 31), 8/13 of the pial lesions were operated on (no mortality, 2 patients with moderate neurological deficits). In the VGAM group 13/18 died and 4 had spontaneous thrombosis (only 1 is neurologically normal). In the nonembolized group 13 lesions have been completely excluded, but only 5 patients are neurologically normal. This fact again stresses the need for prognostic evaluation before treatment and a clear definition of the treatment aims. Analysis of a large number of published series on the management of children with AVMs (1017 cases) reveals inconsistencies that hamper proper evaluation and comparison. In our experience, endovascular treatment always seems to be the best primary treatment in both VGAMs and PAVMs. However, management of children with these lesions requires a large multidisciplinary team, which is the only way of offering the most suitable and effective treatment, the sole guarantee of a good result.     

Prognosis of antenatally diagnosed vein of Galen aneurysmal malformations

In our experience of 168 consecutive cerebral arteriovenous shunts, all antenatally diagnosed lesions were vein of Galen aneurysmal malformations (VGAMs). This series consists of 18 cases of VGAMs detected by ultrasound during the third trimester of pregnancy. There were 12 normal vaginal deliveries, 5 deliveries by cesarean section, and 1 induced abortion. Sixteen newborns (94%) presented with systemic cardiac manifestations as the first clinical symptoms; 12/16 were managed effectively by digitalo-diuretic treatment, while 4 (25%) died shortly after birth form acute heart and/or multiorgan failure with extensive brain damage. Twelve babies underwent embolization via the arterial route in infancy (2 at 2 months of age). Total exclusion was obtained in 8 babies (67%, 3 with 6 months follow-up). Furthermore, 67% of the newborns managed by our team are neurologically normal (Denver and Brunet-Leizine tests). These results emphasize that the pessimism that follows antenatal discovery of these lesions and the previous assumption of a bad prognosis for VGAMs can nowadays be reviewed in the light of transarterial endovascular therapy applied according to a strict clinicoradiological protocol. Interventions in the neonatal period are rarely required. Generally, poorly timed mechanical therapy should be discouraged.     

Hemorrhagic complications in vein of Galen malformations

The authors report on a series of spontaneous intracranial hemorrhages associated with vein of Galen aneurysmal malformations (VGAMs). Thirty-four children with VGAMs have been treated at this institution since 1986. Eight children (24%) harbored the mural-type malformation, and 26 (76%) had the choroidal-type lesion. Two children (25%) with mural lesions and 1 (4%) with a choroidal lesion suffered hemorrhagic complications. Two presented with acute intracranial hemorrhage. A third child developed acute intracranial hemorrhage due to delayed dural sinus thrombosis after endovascular treatment of his choroidal-type VGAM. The subjects ranged in age from 13 days to 17 months at the time of presentation. Each patient underwent rapid radiological evaluation and treatment with endovascular surgery. Post-procedural arteriography demonstrated complete occlusion of the malformation in each patient. For the 3 patients with hemorrhage, follow-up has taken place over 49-, 107-, and 43-month intervals, respectively. Vein of Galen aneurysmal malformations can present with acute intracranial hemorrhage or develop delayed intracranial hemorrhage but respond to treatment using standard endovascular techniques. The presence of hemorrhage does not de facto portend a poor prognosis.     

Onyx液态栓塞剂在脑动静脉畸形治疗中的应用及栓塞后处理的探讨

目的 总结探讨Onyx胶在脑动静脉畸形(AVM)栓塞治疗中的应用及栓寨后治疗.方法 共21例DSA确诊的脑AVM患者,采用Onyx胶治疗;根据栓塞程度行栓塞后处理(随访、立体定向放射治疗、显微手术等).结果 影像学完全栓塞8例(38%),其中术后少最蛛网膜下腔出血1例;次全栓塞4例(19%),1例术后重度脑水肿去骨瓣后因颅内感染自动出院失访,随访观察1例,伽玛刀治疗2例;部分栓塞9例(43%),其中5例手术完全切除,2例伽玛刀治疗,另2例随访观察,其中1例术后3个月出现脑室内出血.结论 Onyx液态栓塞剂有较好的弥散性和可控性,能有效改善脑AVM的栓塞效果,对次全栓塞者可选择随访观察或伽玛刀治疗,部分栓塞者应首先考虑手术切除.     

Transarterial Embolization of Intracranial Arteriovenous Fistulas with Large Venous Pouches in the Form of Venous Outlet Ectasia and Large Venous Varix or Aneurysm : Two Centers Experience

ObjectiveThere are different types of cerebral vascular malformations. Pial arteriovenous fistulas (PAVFs) and dural arteriovenous fistulas (DAVFs) are two entities; they consist of one or more arterial connections to a single venous outlet without a true intervening nidus. The high turbulent flow of PAVFs and aggressive DAVFs with cortical venous reflux can result in venous outflow varix and aneurysmal dilatation. They pose a significant challenge to transvenous embolization (TVE), stereotactic radiosurgery, and surgical treatment. We aim to share our centers’ experience with the transarterial embolization (TAE) for arteriovenous fistulas (AVFs) with large venous pouches and to report the outcome. MethodsThe authors’ two institutions’ databases were retrospectively reviewed from February 2017 to February 2021. All patients with intracranial high flow PAVFs and aggressive DAVFs with venous outlet ectasia and large venous varix and were treated by TAE were included. ResultsFifteen patients harboring 11 DAVFs and four PAVFs met our inclusion criteria. All patients underwent TAE in 17 sessions. Complete angiographic obliteration was achieved after 14 sessions in 12 patients (80%). Four patients (25%) had residual after one TAE session. Technical failure was documented in one patient (6.7%). Fourteen patients (93.3%) had favorable functional outcome (modified Rankin score 0–2). ConclusionsTAE for high flow or aggressive intracranial AVFs is a safe and considerable treatment option, especially for those associated with large venous pouches that are challenging and relatively high-risk for TVE.     

Paragangliomas of head and neck: a treatment option with CyberKnife radiosurgery

Paragangliomas are highly vascular and predominantly benign neoplasms that have traditionally been treated by surgery, embolization and/or external beam radiotherapy (EBRT). The aim of this study is to evaluate the short-term local tumor control and safety of CyberKnife radiosurgery for these lesions. Nine patients, eight with jugular glomus paragangliomas and one with a carotid body paraganglioma, were treated. The target contouring was performed on merged CT and MR images. Eight patients were treated with doses ranging from 11 to 13 Gy (mean 12.5 Gy) in a single fraction and one with 24 Gy in three fractions prescribed to 72–83% isodose line. The mean follow-up was 20 months. One patient died from unrelated causes. There were no local recurrences. All eight patients also demonstrated neurological stability or improvement. Neither cranial nerve palsies have arisen, nor has deterioration beyond baseline been observed. In conclusion, CyberKnife radiosurgery appears to be both safe and effective in the treatment of skull base paragangliomas. Determining whether long-term complications will arise will require further investigation.     

Role of endovascular treatment for ruptured aneurysms involving the anterior spinal artery at the craniocervical junction

Ruptured aneurysms at the craniocervical junction (CCJ) involving the anterior spinal artery (ASA) are rare and consist of heterogenous lesions with variable clinical entities. However, the standard therapeutic strategy for the lesions has not been well-established. Moreover, despite advances in modern neurointervention, reports describing endovascular treatment for this specific lesion have been few. Here, we report three cases of ruptured aneurysms on the pial tributary of the ASA at the CCJ, which were subsequently treated by transarterial glue injection or coil embolization. Endovascular treatment can be a therapeutic option, particularly for these ruptured aneurysms. Either transarterial glue injection or coil embolization can be effective depending on the type of etiology and the surrounding vasculature anatomy.     

97例脑动静脉畸形临床分析

目的:报道97例脑动静脉畸形临床分析。方法:外科手术、血管内栓塞治疗、伽玛刀(γ-刀)治疗和保守治疗。结果:手术治疗66例,优良率81.9％,病残率15.1％,手术死亡率3％。血管内栓塞治疗25例,其中栓塞100％4例,栓塞70％～95％12例,栓塞50％～70％5例,栓塞50％以下4例。3例行γ—刀治疗,3例保守治疗。有7例于手术后、4例于栓塞后行放射治疗。结论:作者认为提高脑动静脉畸形的治愈率,降低病残率及死亡率的关键在于不同部位、类型的脑动静脉畸形选择恰当的治疗方案,对各种治疗方法的适应证进行讨论。     

Multidisciplinary treatment of cavernous sinus dural arteriovenous fistulae with radiosurgery and embolization.

OBJECTIVE: With the advent of interventional neuroradiology and stereotactic radiosurgery, dural arteriovenous fistulae are less often managed with open surgery. We evaluated the outcome of dural arteriovenous fistulae of the cavernous sinus treated with a combination of radiosurgery and embolization. MATERIAL AND METHODS: Twenty dural arteriovenous fistulae located in the cavernous sinus were enrolled in our study. Fifteen patients received X-knife radiosurgery alone and 5 also required embolization, one before radiosurgery and 4 after radiosurgery. The mean volume of the lesions was 2.8 ml (range 0.2-12.6), the corresponding radiation volume was 6.5 ml (range 0.6-24.6), and the conformity index was 2.9 (range 1.8-5.3). The mean peripheral and maximum radiation dose was 17.8 Gy (range 17-20) and 28.3 Gy (range 19-37) Gy, respectively. The clinical and imaging data were analyzed. RESULTS: The mean follow up period was 29 months (23-39). Seventy-five percent (15/20) of patients receiving radiosurgery alone achieved a symptomatic cure and with additional embolization 90% (18/20) were cured. All patients achieved cure on imaging after radiosurgery alone or in combination with embolization. Abnormal imaging findings were observed in two patients after treatment, one had an intracerebral hemorrhage and the other radiation edema, but both were asymptomatic. CONCLUSION: With multidisciplinary treatment with combined radiosurgery and embolization, satisfactory results can be achieved for dural arteriovenous fistulae with a low complication rate. In patients with mild symptoms, radiosurgery is the initial treatment option. Embolization should be performed in patients with severe symptoms or who have failed radiosurgery.     

Surgical management of pediatric cerebral arteriovenous malformations

Background  

Arteriovenous malformations (AVMs) are the most common cause of intracerebral hemorrhage in children. Different options exist for their successful management consisting of surgery, endovascular embolization, stereotactic radiosurgery, or a combination of these treatments.     

140例脑动静脉畸形血管内治疗随访

本文报告140例脑动静脉畸形（AVM)血管内栓塞治疗病人,随访4～42个月。良好:124例（88.6％）差:10例（7.1％),极差:6例（4.2％)。病变完全消失30例（21.4％)。术中血管痉挛16例,但无永久性神经功能障碍。栓塞后立即出血、水肿2例。血管内治疗能使微小型和小型AVM治愈,使中型和大型AVM体积缩小,血流速度减慢,为显微手术和放射外科提供条件。真丝线段和IBCA、NBCA是目前较理想的栓塞材料。     

Chronic encapsulated intracerebral hematoma formation after radiosurgery for cerebral arteriovenous malformation

We report a rare case of chronic encapsulated intracerebral hematoma (CEIH) after radiosurgery for a cerebral arteriovenous malformation (AVM). A 49-year-old male underwent transarterial embolization and surgical excision of a cerebral AVM presenting with cerebral hemorrhage in the left temporal lobe. Stereotactic radiosurgery (SRS) was done after 12 months. Magnetic resonance imaging (MRI) 14 months after SRS showed a small-enhancing lesion close to the left lateral ventricle and marked white matter edema. At that time a diagnosis of radiation-induced necrosis was made and steroids administered. At 43 months after SRS, MRI showed a small-enhancing mass close to the lateral ventricle with a hematoma cavity. Surgical excision was performed and histological examination revealed that the capsule consisted of an outer collagenous layer and an inner granulated layer with deposits of hemosiderin, which was compatible with CEIH. CEIH should be considered after SRS for AVM.     

Gamma knife radiosurgery for the treatment of recurrent seizures after incomplete anterior temporal lobectomy

To evaluate the efficacy and safety of gamma knife radiosurgery (GKS) in treating temporal lobe epilepsy, GKS was performed in four adult patients with recurrent complex partial seizures who underwent incomplete anterior temporal lobectomy (ATL) but were reluctant to undergo a second resective surgery. A marginal dose of 24.5–25 Gy, corresponding to 65–70% isodose curve, was delivered to the treatment target that included the residual amygdala and the head and anterior body of the hippocampus.None of the patients had severe acute side effects but three patients had radiation-induced MRI signal changes around the target volume 13, 20, and 24 months after GKS, respectively. All four patients had significant seizure reduction during the first 6-month period and clinical efficacy persisted throughout the 2-year follow-up period. All of the patients also had improved neuropsychological profiles, including memory function and quality-of-life, compared to their pre-GKS conditions.In conclusion, the safety and clinical efficacy of GKS make it a reasonable and suitable therapeutic alternative for patients with recurrent seizures after incomplete ATL. A higher marginal dose of >25 Gy and wider coverage may be more clinically beneficial but warrant further investigation.     

Inflammatory molecule expression in cerebral arteriovenous malformations.

Inflammatory proteins may play a role in the pathophysiology of cerebral arteriovenous malformations and their response to radiosurgery. The aim of this study was to compare the expression of inflammatory molecules in arteriovenous malformations (AVMs) with that in normal cerebral vessels. Fresh-frozen surgical specimens from 15 AVMs and three control specimens were studied. The expression of P- and E-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), platelet-endothelial cell adhesion molecule (PECAM-1) and von Willebrand factor were examined using immunohistochemistry. AVMs had significant upregulation of E-selectin. VCAM-1 and ICAM-1 upregulation was also observed in AVMs. Pre-operative embolization was associated with increased expression of E-selectin and VCAM-1. This study has provided further evidence that the endothelium of AVMs has different molecular properties than the endothelium of normal cerebral vasculature. Inflammatory molecules may be biologically relevant in the response of vascular malformations to radiosurgery and embolization.     

Pros,cons, and current indications of open craniotomy versus gamma knife in the treatment of arteriovenous malformations and the role of endovascular embolization

The successful treatment of an intracranial arteriovenous malformation poses both technical and conceptual problems to the neurosurgeon. Treatment decisions are made in light of current understanding of the natural history of these lesions. It is important to understand the pros, cons and current indication of open craniotomy vs. gamma knife in the treatment of arteriovenous malformations and the role of endovascular embolization. Surgical removal of an arteriovenous malformation is indicated when the operative risk is less than the morbidity and mortality associated with its natural history. The treatment goal of complete angiographic obliteration of arteriovenous malformations is achieved most effectively by microneurosurgery in low-grade lesions. Large lesions frequently require a combination of embolization and microsurgery. Although recent advances in technology and medical management have allowed previously inoperable arteriovenous malformations to be surgically excised, there is still a small group of arteriovenous malformations that cannot be excised safely due to their size and location. Stereotactic radiosurgery is clearly an important adjunct in the multimodality treatment approach for large arteriovenous malformations. Endovascular embolization can potentially increase safety and efficacy in the treatment of arteriovenous malformations when applied to selective cases with well-defined treatment goals.     

大型脑动静脉畸形的伽玛刀体积分割治疗

目的 探讨伽玛刀体积分割治疗大型（体积>10 cm3）脑动静脉畸形（AVM）的临床疗效。方法 回顾性分析 2007~2017年收治的13例大小脑AVM的临床资料,均采用伽玛刀体积分割治疗,时间间隔3~18个月,治疗的AVM总体积平均为18.2 cm3（13.5~52 cm3）,首次治疗的体积平均为14.1 cm3（8~23 cm3）;边缘剂量平均为16.6 Gy（14~20 Gy）。13例随访24~92个月,平均为43.2个月。结果 末次随访影像显示,6例血管巢闭塞,4例病灶体积减小>75%,3例病灶缩小<50%。8例癫痫中,6例缓解或改善。1例治疗后7个月出现脑出血,1例治疗后6个月因脑放射性副反应出现肢体感觉运动障碍。结论 伽玛刀体积分割治疗大型脑AVM是一种安全、有效的方法,大多数临床症状可明显改善。     

Predicting factors for the follow-up outcome and management decisions in vein of Galen aneurysmal malformations

Purpose  

Vein of Galen aneurysmal malformations (VGAMs) are choroidal arteriovenous malformations that develop during an early embryonic stage. Although recent reports have shown improved outcome for these patients, the overall outcome still is poor. In this study, we evaluated the clinical, imaging, and angiographic features that may predict the outcome in VGAM patients.     

Dural Arteriovenous Fistula Involving an Isolated Sinus Treated Using Transarterial Onyx Embolization

The authors present a case of isolated dural arteriovenous fistula (DAVF) in the transverse sinus, which developed six years after microvascular decompression caused by hemifacial spasm via suboccipital craniectomy. The lesion was successfully treated by transarterial embolization using Onyx. We reviewed the related radiologic and therapeutic features of DAVF involving an isolated sinus and described the feasibility of the use of Onyx.     

Two cases of cystic enlargement of vestibular schwannoma as a late complication following gamma knife surgery

Cyst formation is the most common long-term complication after gamma knife surgery (GKS) for cerebral arteriovenous malformations; however, this rarely occurs after GKS for vestibular schwannoma (VS). We describe two patients that developed aggressive, symptomatic large cysts at more than 4 and 12 years after GKS for VS, although the tumor control for these patients had been acceptable at 3 and 11 years, respectively. During the surgery, a reddish lesion, which was distinct from the surrounding tumor, was observed. The microscopic examination of the reddish lesion revealed dilated capillary vessels and hemorrhage, which was compatible with late radiation changes; these were usually seen in arteriovenous malformations following radiosurgery. The present patients indicated that cyst formation and enlargement may occur as a late complication following GKS even in extra-axial benign tumors such as VS.     

Noradrenaline- and time-dependent changes in neocortical α2- and β1-adrenoceptor binding in dorsal noradrenergic bundle-lesioned rats

A 6-hydroxydopamine-induced lesion of the dorsal noradrenergic bundle (DNB) in rats markedly decreased neocortical noradrenaline concentration (NNC) by 72–100% as measured 1, 3 and 13 months after the lesioning procedure. The concomitant assessment of neocortical α₂- and β₁-adrenoceptor binding (NAAB and NBAB, respectively) usually indicated significant increases of 25–74% for these two variables. There were, however, cases of unchanged NAAB and NBAB which presumably reflected an incomplete DNB lesion and a consequent time-related, partial recovery of NNC. The results emphasize the potential for long-term sequelae of the DNB lesion, and the existence of a critical NNC threshold (10–30% of control NNC values) which modulates postsynaptic α₂ and β₁-adrenoceptor density.