Transarterial embolization of vein of Galen aneurysmal malformation after unsuccessful stereotactic radiosurgery

The authors present three cases of vein of Galen aneurysmal malformations (VGAMs) diagnosed in infancy and submitted by the referring teams for stereotactic radiosurgery as the initial therapy (therapeutic doses ranging between 20–25 Gy and 40–50 Gy to the peak dose). After the conventional follow-up of 18–24 months, no change could be detected in the angioarchitecture of the lesions. All three cases were then referred for endovascular treatment and underwent embolization by the transarterial route using liquid adhesives (N-butyl cyanoacrylate). This resulted in complete anatomical exclusion of the lesion. Regardless of the theoretical efficiency of radiosurgery in the management of brain arteriovenous malformations, the present authors believe that transarterial embolization remains the treatment of choice in VGAMs. It offers a high rate of morphological cure and the best chances for normal neurocognitive development. The time required by radiosurgery to achieve a significant result is too long for developing and maturing brain and may not prevent the negative effects of the lesion, mainly in regard to hemo- and hydrodynamic disorders (atrophy, subcortical calcifications, etc.) created by the VGAM, thus leading to irreversible mental retardation.     

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.     

Hydrodynamics in vein of Galen malformations

Forty-three patients with vein of Galen aneurysmal malformations (VGAM) referred to us for endovascular treatment between 1985 and 1990 and 335 additional cases published in the literature were reviewed with particular attention to the presence of ventricular enlargement and outcome after shunting. Hydrocephalus was the second most frequent symptom (46.8%); it is more frequent in infants (73%) than in children, adults (30%) or neonates (15%). Of the patients reported in the literature, 17.9% had undergone shunting. Within the shunted population there was an overall morbidity of 41% and a mortality of 10% (especially in the infant group). In our series 17 patients (39.5%) were shunted and a significant difference in the clinical outcome was noted between the shunted and the nonshunted group. Of the nonshunted patients, 66.6% were free of any neurological deficit or mental retardation and fewer than 5% presented with significant mental retardation. On the other hand, only 33.3% of the shunted patients had a favorable outcome and more than 15% developed significant mental retardation. Among the various causes of hydrocephalus in patients with VGAMs, such as obstruction of the aqueduct, subarachnoid hemorrhage, or ex vacuo hydrocephalus, high venous pressure may be of particular importance. In this article a physiopathological interpretation of the hydrodynamics in VGAMs is developed and a speculative explanation for CSF disorders related to ventricular shunting proposed. Treatment of hydrocephalus in VGAMs can be achieved through obliteration of the malformation or at least diminishing the venous pressure; surgical ventricular shunting does not have to be the first treatment of hydrodynamic disorders associated with VGAMs, especially in infants.     

Reversible tonsillar prolapse in vein of Galen aneurysmal malformations: report of eight cases and pathophysiological hypothesis

We report eight cases of vein of Galen aneurysmal malformation (VGAM) assoicated with a Chiari type I malformation. In four cases magnetic resonance imaging (MRI) or computed tomography performed in the neonatal period did not demonstrate the posterior fossa anomaly, which appeared on later scans. In the other cases the MRI was performed in infancy and the anomaly was already present. We compared the venous phases of the posterior fossa angiograms and the MRI in these patients. In all eight cases, the angiograms showed a reflux in the cerebellar veins, via the petrous vein, associated with a uni-or bilateral stenosis or thrombosis of the distal posterior dural sinuses. Furthermore, in two cases the posterior fossa returned to normal on MRI following endovascular treatment, while in three cases the herniation of the cerebellar tonsils decreased after the embolization. Tonsillar prolapse becomes irreversible when the venous outlet is incapable of taking the flow even when the VGAM has been treated adequately. In eight additional cases of VGAM for which MRI and angiogram studies were available and in which stenosis or thrombosis of posterior dural sinuses was present without tonsillar prolapse, no reflux into the cerebellar veins was shown. We suggest that the posterior fossa hydrovenous congestion is a result of inadequate venous drainage and that the tonsillar descent is reversible if adequate venous drainage is reconstituted following therapeutic embolization of the fistula. Tonsillar prolapse is not a consequence of mass or raised intraventricular pressure. Our observation suggests that in some other conditions, the Chiari I malformations may be secondary to early hydrovenous dysfunction of the posterior fossa.     

Pathologic findings in a patient with a vein of Galen aneurysm treated by staged endovascular embolization

Vein of Galen aneurysms are uncommon malformations that can be treated with a combination of endovascular embolization and surgery. Since the relevant techniques are new and innovative, their pathologic sequelae are not yet well described. A patient treated with staged embolization over a 15-month period developed evidence of cerebral venous hypertension on angiography. At necropsy, we observed marked myointimal proliferation of the aneurysm wall, dura, and cerebral vessels in addition to severe widespread encephalomalacia, calcinosis, and rare mural thrombi. These vascular changes have not been previously described in cases of vein of Galen aneurysm, and may, in part, be a consequence of embolization therapy.     

Susceptibility weighted imaging in the diagnostic evaluation of patients with intractable epilepsy

Aim:   Dedicated magnetic resonance imaging (MRI) protocol can diagnose epileptogenic abnormalities in patients with intractable epilepsy. However, it is not sufficiently sensitive to detect small calcified lesions that may result from infections, tumors, or vascular malformations. This study aims to study the impact of the addition of T2*gradient echo/susceptibility weighted imaging (T2*GRE/SWI) sequence to a dedicated MRI protocol.
Method:   One hundred thirty-seven patients with intractable epilepsy underwent MRI using conventional epilepsy protocol with addition of T2*GRE/SWI sequence. Comparison of the images with and without these sequences was done for detection of calcified abnormalities/vascular abnormalities. In patients with calcified lesions, MRI findings were correlated either with histopathology or computerized tomography (CT) to confirm the presence of calcification.
Results:   In 16 patients the sequence gave additional information compared to conventional imaging protocol. The sequence helped in better characterization of lesions in all patients . In three patients it helped in detecting the lesion and in another three it appeared useful as it best characterized the lesions. Additional lesions were detected in two patients with old calcified granulomas. Important additional information was supplied in four patients, whereas in the remaining patients lesion conspicuity was increased.
Conclusion:   T2*GRE/SWI sequence should form part of routine epilepsy protocol as it increases sensitivity by detecting occult calcified lesions or vascular malformations that may be responsible for the patient's seizures. This is especially important in patients from developing countries who have post-infective calcified lesions responsible for seizures and who undergo only MRI as the imaging modality for intractable seizures.     

Normal galenic drainage of the deep cerebral venous system in two cases of vein of Galen aneurysmal malformation

Introduction Vein of Galen aneurysmal malformations (VGAM) are assumed to be related to the persistence of the embryonic median prosencephalic vein of Markowski, which does not involute in cases of VGAM and becomes the venous collector of the shunt, characteristic of the malformation. The arterial feeders of VGAMs are all primitive meningeal arteries present during the embryonic period of the constitution of the malformation. It has also been assumed that the internal cerebral veins were absent in patients presenting with VGAM. There is no clear evidence indicating, however, that the deep venous structures cannot develop normally.Case reports We report on two cases of VGAM in which superselective retrograde transvenous catheterization and MRI demonstrated that normal internal cerebral veins were draining into the aneurysmal vein of Galen.Conclusions It is conceivable that, as in our patients, this drainage pattern is only angiographically detectable via selective retrograde transvenous drainage. The possibility of such normal deep galenic venous drainage must be considered in VGAM management, as it may imply occurrence of adverse effects when the malformation is occluded on the venous side.A commentary on this paper is available at     

Vein of Galen malformation

Since 1984, 43 patients with true vein of Galen ancurysmal malformations have been referred to us and managed according to our patient selection, technique, and follow-up guidelines. Thirty-four were embolized transarterially with bucrilate (isobutyl cyanoacrylate) or enbucrilate (N-butyl cyanoacrylate) embolization. No cutdown or hypotension during or after the embolization was used and no balloon catheter was employed. Forty-seven percent of the children had a completely occluded lesion which was confirmed when the child was at least 6 months of age at the follow-up angiographic examination; 52.9% were found to be completely normal or only to have mild cardiac failure that could be treated medically or moderate macrocephaly without neurological symptoms or mental retardation. In the embolized group 5.8% died as a result of the wrong treatment (1 case) or poor timing of embolization 3 days after ventricular shunting (1 case). The overall mortality (embolized and non-embolized groups) in the neonatal children was 27.7% with a total of 18.6% for all ages. Complete morphological exclusion of the arteriovenous malformation was accomplished in 41.9%; 74.4% of all children referred are now clinically normal or present moderate mental retardation which is diminishing. There was 3% neurological morbidity in the embolized group (only following the venous approach) in 78 sessions and more than 100 arteries embolized. These results compare favorably with surgical or other techniques of arterial embolization (balloon or particles), as well as transvenous (transtorcular or transfemora) embolization, where the morbidity and mortality are significantly higher and the late clinical evaluation is seldom satisfactory. We believe that presently there is no indication for surgery as a primary form of treatment if a properly trained interventional neuroradiological team is available.     

磁敏感加权成像在脑静脉性血管畸形诊断中的应用

目的探讨磁敏感加权成像(SWI)在脑静脉性血管畸形中的诊断价值。方法回顾性分析21例脑静脉性血管畸形患者的影像学资料,所有患者均行常规MRI平扫与SWI序列扫描,评价SWI序列对脑静脉性血管畸形检出的优越性。结果 SWI发现脑静脉性血管畸形21例,T1WI发现病灶17例,T2WI发现病灶18例,常规MRI扫描序列呈点状或条形流空信号,且只可显示大部分扩张的引流静脉及部分扩张的髓静脉,SWI可以清晰的显示所有扩张的髓静脉及粗大的引流静脉,呈典型"水母头"状。结论 SWI较常规MRI扫描序列对脑静脉性血管畸形的显示更为敏感。     

The use of adenosine in the treatment of a high-flow vein of Galen malformation in an adult

The treatment of high-flow vein of Galen aneurysmal malformations (VGAM) remains a therapeutic challenge for the neurosurgeon and the neurointerventionalist, as it is associated with high morbidity and mortality rates despite recent advances in open cranial surgery and interventional neuroradiology. A 37-year-old patient presented with a history of non-specific headaches. He had a history of heart failure since birth that was caused by an untreated VGAM. Intravenous boluses of adenosine were injected as an attempt to slow down the arteriovenous shunting of a VGAM prior to endovascular treatment. Adenosine can be a very useful adjunct in patients with extremely high arteriovenous shunting. n-butyl cyanoacrylate (n-BCA) should be the embolic material of choice due to its quick polymerization and adhesive properties.     

Galen静脉动脉瘤样畸形一例并文献复习

目的 探讨Galen静脉动脉瘤样畸形的临床特征和血管内治疗。方法 报告1例Galen静脉动脉瘤样畸形病例，结合相关文献分析该病的分类、临床表现和影像特征，探讨其栓塞治疗。结果 Galen静脉动脉瘤样畸形是一种少见的血管性疾病，约占颅内血管畸形的1％。不同的类型影像特征和临床表现不同，确诊和治疗有赖于脑DSA，血管内栓塞治疗效果较好。结论 Galen静脉动脉瘤样畸形有较高的致残率和死亡率，血管内治疗是目前最好的治疗方法。     

磁敏感加权成像及其PV值测定对不同时期脑静脉窦血栓的诊断价值

目的比较不同序列磁共振成像对不同时期脑静脉窦血栓形成(CVST)的敏感性,探讨磁敏感加权成像(SWI)序列及其相位值(PV)测定对CVST的诊断意义。方法采用3.0 T磁共振系统,对30例患者进行轴位T1WI、T2WI、T2*WI、SWI及MRV序列检查,其中20例患者进行DSA检查。观察不同序列静脉窦血栓的信号特点,定量测量静脉窦血栓的PV值变化,并比较不同序列对不同时期CVST检出的敏感性。结果正常静脉窦PV值为+0.136±0.022,SWI呈高信号。急性期(≤5d)静脉窦血栓PV值为-0.642±0.024,SWI呈低信号;亚急性期(6～15d)静脉窦血栓PV值为+0.146±0.021,SWI呈高信号或以高信号为主的混杂信号;慢性期(≥16d)静脉窦血栓PV值为-0.842±0.015,SWI呈低信号。静脉窦血栓PV值与正常静脉窦PV值差异有统计学意义(P<0.05)。急性期、亚急性期及慢性期静脉窦血栓PV值差异有统计学意义(P<0.05)。SWI序列对急性期和慢性期(97.20%,92.30%)静脉窦血栓的检出率高于T1WI(63.80%,38.40%)和T2WI(0.00%,30.70%)序列,对亚急性静脉窦血栓(48.00%)的检出率低于T1WI(100%)和T2WI(72.00%)序列。SWI和T2*WI对静脉窦血栓的检出率差异有统计学意义(P﹥0.05)。结论 SWI序列对急、慢性期CVST的检出有较高的敏感性,PV值测定能够为CVST的诊断提供客观的量化标准。     

Galen静脉血栓临床和影像学表现

目的探讨Galen静脉血栓的病因、发病机制、临床、影像学表现及治疗。方法收集10例Galen静脉血栓患者的临床资料和影像学图像,结合Galen静脉解剖学及其血栓形成后病理学改变进行分析。结果 10例患者中,女性7例,男性3例,年龄16~49岁,平均年龄29.1±9.06岁,均急性起病,多以头痛、呕吐为首发症状,病情逐渐进展,可出现意识不清并伴有抽搐等症状。经治疗,6例治愈,2例好转,2例死亡。结论 Galen静脉血栓的病因多种;以急性颅内压增高表现为主,临床表现多样,多出现头痛、呕吐、抽搐及意识障碍等;Galen静脉血栓在急性期CT上呈高密度影,在亚急性期MRI上T_1WI、T_2WI均呈高信号有助于诊断;及时应用低分子肝素抗凝有望取得良好效果。     

Magnetic resonance imaging,susceptibility weighted imaging and quantitative susceptibility mapping findings of pantothenate kinase-associated neurodegeneration

Pantothenate kinase-associated neurodegeneration (PKAN) is extremely rare. In this study, we aimed to evaluate the magnetic resonance imaging (MRI) findings of PKAN patients. Conventional MRI and susceptibility weighted imaging (SWI) sequences and quantitative susceptibility mapping (QSM) maps of six patients from three PKAN families and eight healthy male volunteers were retrospectively analyzed. Iron content was represented by QSM values. The typical eye-of-the-tiger sign (n = 4) and hyperintensity (n = 2) of the bilateral globus pallidus (GP) were observed on T2WI sequences. The SWI signal was low (n = 5), and the QSM values were obviously higher (n = 2), which manifested as a reversed eye-of-the-tiger sign (n = 4) and hyperintensity (n = 2) on the QSM map. The QSM values were higher in the bilateral central GP, bilateral peripheral GP, and bilateral substantia nigra (SN) and lower in the left red nucleus (RN) compared with the healthy controls. No significant differences were observed in the right RN, bilateral thalamus and bilateral occipital regions. Low signals on SWI sequences and high QSM values with a reversed eye-of-the-tiger sign on QSM maps are important for the diagnosis of PKAN, especially in patients who do not show the eye-of-the-tiger sign in early stages. The eye-of-the-tiger sign observed on T2WI is helpful in diagnosing PKAN when the disease has already progressed to an advanced stage.     

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.     

Dilated vein of Galen in Kabuki syndrome

Kabuki syndrome (KS) comprises multiple congenital abnormalities and is characterized by a peculiar facial appearance, dermatoglyphic anomalies, mental retardation, skeletal abnormalities and postnatal growth retardation. We describe the case of a 23-month-old boy with the typical features of KS who had several malformations in the veins of the brain, which had not previously been described in patients with this syndrome. The MRI phlebogram of this patient showed that the vein of Galen was dilated and that it drained anomalously. The sinus rectus was abnormal and the longitudinal inferior venous sinus was absent. In view of this finding, together with the fact that structural brain abnormalities in KS are more frequent than in other congenital syndromes with multiple malformations, we propose that MRI be used in the diagnostic work-up of all patients with KS.     

Ethylenevinylalcohol copolymer (Onyx-18) used in endovascular treatment of vein of Galen malformation

Background Vein of Galen malformations (VGM) are rare congenital arteriovenous fistulas that usually present with heart failure in the neonate. Endovascular treatment options in the past have utilized coils, balloons, and acrylics. Case report We present, for the first time in the literature, a case of an infant with VGM treated initially with staged coil embolizations followed 1 year later by the transarterial and transvenous catheter based injection of Onyx-18 (ethylenevinylalcohol copolymer) in a single treatment session. The fistula was eliminated, and the infant’s cardiopulmonary symptoms were improved.     

核磁共振脑灌注成像及DWI联合应用在诊断早期脑梗死缺血半暗带中的临床价值

目的 探讨核磁共振脑部灌注加权成像(PWI)及脑部弥散加权成像(DWI)联合应用在诊断早期脑梗死缺血半暗带中的临床价值。方法 本研究中的受试对象均来自2016年1月-2017年4月来本院就诊的脑梗死患者,选出符合纳入标准的100例作为研究对象,并根据脑梗死发生时间分成超急性期、急性期、亚急性期和慢性期,分别观察PWI和DWI表现,以表观弥散系数(ADC)为DWI的检测评价指标,以局部脑血容量(rCBV)、局部脑血流量(rCBF)、平均通过时间(MTT)和达峰时间(TTP)为PWI的检测评价指标,并比较不同时期脑梗死的PWI和DWI表现。结果 随着脑梗死患者发病时间的延长,T₂WI显示信号随之增高,DWI信号随之降低,ADC信号随之增高。随着梗死时间延长,梗死区ADC值随之增加,健侧对应区随着梗死时间的变化,ADC值无明显变化; 在每个不同分期中健侧对应区的ADC值均高于梗死区(P均<0.05); 超急性期rCBV和rCBF值均为降低信号,MTT和TTP均为升高信号; 急性期rCBV、rCBF、MTT和TTP值在三种信号上均有表现,但rCBV和rCBF值均以降低信号为主,MTT和TTP均以升高信号为主; 亚急性期中rCBV和rCBF为正常和降低信号,其中以正常信号为主,MTT和TTP均为降低和升高信号,并以升高信号为主; 慢性期rCBV和rCBF均表现为降低信号,MTT和TTP均为降低和升高信号,并以降低信号为主; 超急性期DWIPWI均有表现,并以DWIPWI均有表现,并以DWIPWI为主; 亚急性期DWI=PWI和DWI>PWI均有表现,并以DWI=PWI为主; 慢性期均为DWI=PWI。结论 PWI联合DWI对脑梗死早期的诊断价值较高,PWI对缺血半暗带有较好的诊断,其与DWI相结合可更准确地判定缺血半暗带。