Hortensia Alvarez

Cerebral arteriovenous malformations in children - Management of 179 consecutive cases and review of the literature

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.

Classification of spinal cord arteriovenous shunts: Proposal for a reappraisal - The Bicêtre experience with 155 consecutive patients treated between 1981 and 1999

OBJECTIVE Spinal cord arteriovenous shunts (SCAVSs) are currently classified according to their morphological features. Certain shunts cannot be fully integrated into the predetermined categories that are usually described, however. Can these classifications be reevaluated on the basis of recent anatomic, biological, and genetic advances? METHODS We reviewed the clinical and radiological files for 155 SCAVSs that were treated at Hôpital Bicêtre between 1981 and 1999. The lesions were examined with respect to their number (single or multiple), their primary architectural type (nidus or fistula), and their possible links with associated metameric lesions. RESULTS All SCAVSs were either arteriovenous malformations or fistulae, with the latter being either micro- or macrofistulae. All SCAVSs corresponded to three categories, i.e., genetic hereditary lesions (macrofistulae and hereditary hemorrhagic telangiectasia), genetic nonhereditary lesions (all of which were multiple lesions with metameric or myelomeric associations), and single lesions (which could represent incomplete presentations of one of the previous groups). Of the SCAVSs in our series, 81% were single lesions and 19% were multiple; among these, 59% were true intradural shunts with metameric features. Ten cases of Cobb syndrome, three cases of Klippel-Trenaunay syndrome, and two cases of Parkes-Weber syndrome, all with associated cord lesions, were observed. Nineteen percent of SCAVSs were fistulae; 23% of those were macrofistulae, of which 83% were related to Rendu-Osler-Weber disease. CONCLUSION It seems legitimate to propose a categorization that takes into consideration a primary malformation (nidus or fistula) that evolves with time and in which angioarchitectural changes occur. Recognition of the factors originally responsible for the shunt (e.g., genetic hereditary or genetic nonhereditary) allows a different classification of SCAVSs.

Effect of partial targeted N-butyl-cyano-acrylate embolization in brain AVM.

Summary. Background: The management of cerebral arteriovenous malformations needs effective treatments. So far, no study has shown that partial targeted embolization treatment (PTET) reduces the risk of intracranial hemorrhage with respect to the natural history of the malformation. Methods: The pre-treatment and post-treatment-initialization hemorrhage incidences of neuro-interventional patients were compared. Two hundred fifteen patient years from 519 patients were used to observe the short term course of the untreated disease. Five hundred patient years from 326 patients were used to observe hemorrhage after the start of treatment. The Kaplan-Meier estimator of hemorrhage free time under treatment was compared with results in the literature. Confounding influences resulting from selection processes or the disease parameters were studied. Results: The yearly hemorrhage incidence rate of all untreated patients was observed as 0.089 (95% CI [0.053, 0.138]). This rate was 0.052 (95% CI [0.019, 0.114]) in the subgroup of patients who underwent PTET later. In the same group the observed annual rate after the start of PTET was 0.036 (95% CI [0.021, 0.057]). Crawfords results about intracranial hemorrhage during the natural course show the lowest risk values compared to other published studies [3]. There was a significant difference between the Crawfords reference data and the ICH incidence after the start of PTET in the neuro-interventional population (p=0.037). The morbidity risk in treated patients was 5.3% for a transitory and 2% for a persisting neurological deficit. Mortality results were compared with those of Crawford. Conclusion: The neuro-interventional patients under study show a lower hemorrhage risk than the population studied by Crawford. A significant superiority with respect to hemorrhage risk is established two years after the start of the PTET treatment.

Spinal cord intradural arteriovenous fistulae: Anatomic, clinical, and therapeutic considerations in a series of 32 consecutive patients seen between 1981 and 2000 with emphasis on endovascular therapy

OBJECTIVE:To review our series of intradural spinal cord arteriovenous fistulas (SCAVFs), analyzing symptoms and related angioarchitecture, and to study the morphological and clinical results of embolization. METHODS:Thirty-two SCAVFs (in 22 adults and 10 children) were treated between 1981 and 2000. These lesions were classified as microarteriovenous fistulas (mAVFs) or macroarteriovenous fistulas (MAVFs) according to shunt morphology. Location, architecture, presenting symptoms, and age group were detailed. The selection of patients for endovascular versus surgical treatments was analyzed, as were the anatomic and clinical results obtained by embolization with n-butylcyanoacrylate. Clinical status was evaluated according to the Karnofsky Performance Scale score. RESULTS:Ten SCAVFs were found in the pediatric population (four mAVFs and six MAVFs). All four mAVFs presented with acute symptoms. Three mAVFs (two cervical and one thoracic) presented hematomyelia; in one patient with a thoracic AVF, subarachnoid hemorrhage was suspected. All six MAVFs were located in the thoracolumbar cord (five associated with hereditary hemorrhagic telangiectasias). Four of the six MAVFs presented with hemorrhage. In the adult population, there were 21 mAVFS (95%) and one MAVF (5%). Only two mAVFs were found in the cervical cord, all other shunts affecting the thoracolumbar region. Hemorrhage was present in 6 of the 22 cases seen in adults (27%). The symptoms of SCAVFs did not differ from those found in spinal cord arteriovenous shunts of nidus type. Pial venous reflux and congestion were the most frequently encountered features in both the adult and pediatric groups. Arterial aneurysms (different from false aneurysms) were not found in association with hemorrhagic presentation of SCAVFs. Mean follow-up in our series was 3.3 years. Of the MAVFs, 86% were embolized, with 67% cured. The others had more than 75% occlusion. All patients followed up improved significantly. Of the mAVFs, 48% were treated endovascularly. Successful embolization was performed in 75% of patients. One patient was not embolized because of vasospasm, whereas 67% percent of mAVFs were completely occluded, 22% were more than 90% occluded, and 11% were 75% occluded. Complementary surgery was deemed unnecessary. All patients with mAVFs improved significantly at follow-up. Transient complications occurred in 22% of all patients, with no permanent morbidity or mortality. No patient bled or rebled after embolization. Thirty-six percent of mAVFs were operated on because of anticipated technical difficulties for endovascular approach or distal localization of the shunt. CONCLUSION:Endovascular treatment of SCAVFs stabilizes, normalizes, or improves neurological symptoms in all patients at long-term follow-up, with no bleeds or rebleeds. Embolization of SCAVFs with glue is a safe treatment that compares favorably with other approaches and significantly improves the poor natural history of the disease.

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.

Intracranial aneurysms: from vessel wall pathology to therapeutic approach.

An aneurysm is a focal dilatation of an arterial blood vessel. Luminal forces, such as high blood flow, shear stress and turbulence, are implicated in the pathogenesis of intracranial aneurysms, and luminal characteristics, such as sac size and morphology, are usually essential to the clinical decision-making process. Despite frequent clinical emphasis on the vessel lumen, however, the pathology underlying the formation, growth and rupture of an aneurysm mainly resides in the vessel wall. Research on the morphology and histopathology of the vessel wall reveals that intracranial aneurysms do not constitute a single disease, but are a shared manifestation of a wide range of diseases, each of which has a unique natural history and optimum therapy. This Review classifies intracranial aneurysms by vessel wall pathology, and demonstrates that understanding the morphology and pathology of this structure is important in determining the therapeutic approach. The article concludes that aneurysms represent a symptom of an underlying vascular disease rather than constituting a disease on their own.

Cerebral Proliferative Angiopathy Clinical and Angiographic Description of an Entity Different From Cerebral AVMs

Background and Purpose— The purpose of this article is to describe “cerebral proliferative angiopathy” (CPA) as a clinical entity, which may be regarded as separate from “classical” brain AVMs in angioarchitecture, natural history, clinical presentation, and, therefore, treatment and which can be discerned from other cerebral AVMs by characteristic imaging features. Methods— In a prospectively entered databank encompassing 1434 patients with brain AVMs, a subgroup of 49 patients harboring specific angiographic characteristics were identified. Their charts and imaging films were retrospectively reviewed. Results— We found a preponderance of CPA in young (mean age: 22) females (67%). Clinical symptoms were seizures, disabling headaches, and stroke-like symptoms; hemorrhagic presentations were exceptional. On cross-sectional imaging, CPA demonstrated as a diffuse network of densely enhancing vascular spaces with intermingled normal brain parenchyma. The discrepancy between the large size of the nidus and the small shunting volume, the absence of flow-related aneurysms, the presence of diffuse angiogenesis (eg, transdural supply, progressive arterial occlusion), and the small calibre of a multitude of feeding arteries and draining veins were the angiographic hallmarks of this disease. Conclusion— The diffuse angiogenetic activity is presumably related to reduced perinidal perfusion and subsequent chronic cortical ischemia. Natural history demonstrates a low risk of hemorrhage. CPA may be regarded as a separate clinical entity different to “classical” cerebral AVMs, because normal brain is interspersed with the abnormal vascular channels increasing the risk of neurological deficit in aggressive treatments, which in the light of the natural history does not seem to be indicated.

Wyburn-Mason or Bonnet-Dechaume-Blanc as Cerebrofacial Arteriovenous Metameric Syndromes (CAMS): A New Concept and a New Classification

The diagnosis of Bonnet-Dechaume-Blanc or Wyburn-Mason syndrome encompasses a spectrum of phenotypic expression. Features of the syndrome as originally described, and common to all, include arteriovenous malformations of the brain and orbit (with retinal and/or retrobulbar lesions). A portion of these patients manifest the complete expression of the disease with additional high-flow arteriovenous malformations of the maxillofacial or mandibular regions. These present the distinct and additional risks of life-threatening epistaxis or gingival haemorrhage. We suggest new diagnostic criteria for the syndrome. Applying insights from modern developmental biology to our series of 15 patients (the largest to date), together with a review of the literature, we have recognised metameric patterns of involvement in what we believe to be a disease of the neural crest or adjacent cephalic mesoderm. This allows us to propose a new rational classification reflecting the putative, underlying disorder and to suggest a new name: Cerebrofacial Arteriovenous Metameric Syndrome (CAMS).

Embolization of spinal cord arteriovenous shunts: morphological and clinical follow-up and results--review of 69 consecutive cases.

OBJECTIVEWe sought to analyze the results of embolization in patients with intradural spinal cord arteriovenous shunts. METHODSThe clinical and radiological files of 69 of a population of 155 patients treated with embolization between 1981 and 1999 were reviewed retrospectively. The patients’ clinical status was evaluated according to Karnofsky Performance Scale score. Twenty-one (14%) of 155 patients were treated surgically because they were thought to be poor candidates for embolization. Twenty-four (15%) of 155 patients were considered untreatable with surgery or embolization; in these patients, follow-up was proposed, but only 8 of them were followed appropriately and remained stable after the first consultation. Forty-one (26%) of 155 patients consulted our group, but no follow-up could be obtained. In 69 (45%) of 155 patients, comprising 20 children and 49 adults, endovascular treatment was performed with the patients under general anesthesia and without provocative tests, mainly with acrylic glue, in 99% of these patients. RESULTSThe mean number of diagnostic and therapeutic sessions was 3.5 per patient, and the mean number of pure therapeutic sessions was 1.5 per patient. Follow-up ranged between 6 months and 18 years (mean, 5.6 yr). In 16% of patients, anatomic obliteration of spinal cord arteriovenous shunts was obtained. Embolization reduced more than 50% of the spinal cord arteriovenous shunts in 86% of cases. No recanalization was noted on follow-up angiograms. Good clinical outcomes were obtained in 83% of the patients: 15% of them were asymptomatic, 43% were improved, and 25% were stable. In 4% of patients, embolization failed to stabilize the disease. Transient deficits were seen after embolization in 14% of the patients, and permanent severe complications occurred in 4% of the patients (Karnofsky Performance Scale score ≤70). Mild worsening was seen in 9% of the patients (Karnofsky Performance Scale score, 80). No bleeding or rebleeding was seen after endovascular treatment was considered to have been completed. CONCLUSIONThis study proves that embolization with acrylic glue is a therapeutic option that compares favorably with surgery or embolization with other agents (particles, coils, or balloons). It offers stable long-term clinical results, despite not necessarily achieving total cure. Studies of larger series with longer follow-up are necessary to confirm these encouraging therapeutic data.

Sinus pericranii: diagnostic and therapeutic considerations in 15 patients

IntroductionSinus pericranii (SP) is a rare, usually asymptomatic condition characterized by a large communication between the intra- and the extracranial venous drainage pathways in which blood may circulate bidirectionally through dilated veins of the skull. We describe our diagnostic and therapeutic experience with SP, with a special focus on the vascular analysis of digital subtraction angiography (DSA).MethodsDSA images of 15 patients were evaluated with regard to the delay in opacification of the scalp vessels, the absence or distortion of the superficial cortical veins in the vicinity of the SP, the drainage patterns of the superior sagittal sinus, and the degree of maturation of the venous outlets of the brain. SP were classified either as “dominant”, if the main stream of contrast flow used the SP to drain the brain bypassing usual venous outlets, or as “accessory”, if only a small part of the venous outflow occurred through the extradiploic vessels.ResultsAll patients presented with a nonpulsatile, soft-tissue mass. The lesion was on the midline in 14 of 15 patients, frontal in 12 patients, and parietal in 2 patients. In 13 patients, associated intracranial venous anomalies were present, eight of which were developmental venous anomalies. Seven patients had a dominant SP, and eight an accessory SP.ConclusionSP can be considered the cutaneous sign of an underlying venous anomaly. If treatment is contemplated, analysis of the drainage pattern of the SP has to be performed. Treatment should be avoided in dominant SP or if its accessory role constitutes the only collateral pathway of an underlying venous anomaly.