Endovascular treatment of a ruptured posterior fossa pure arterial malformation: illustrative case

BACKGROUND

Pure arterial malformations (PAMs) are rare vascular anomalies that are commonly mistaken for other vascular malformations. Because of their purported benign natural history, PAMs are often conservatively managed. The authors report the case of a ruptured PAM leading to subarachnoid hemorrhage (SAH) with intraventricular extension that was treated endovascularly.

OBSERVATIONS

A 38-year-old man presented with a 1-day history of headaches and nausea. A computed tomography scan demonstrated diffuse SAH with intraventricular extension, and angiography revealed a right posterior inferior cerebellar artery-associated PAM. The PAM was treated with endovascular Onyx embolization.

LESSONS

To the authors' knowledge, only 2 other cases of SAH associated with PAM have been reported. In those 2 cases, surgical clipping was pursued for definitive treatment. Here, the authors report the first case of a ruptured PAM treated using an endovascular approach, showing its feasibility as a treatment option particularly in patients in whom open surgery is too high a risk.

Traumatic cerebrovascular injury: clinical characteristics and illustrative cases

OBJECTIVE

Traumatic cerebrovascular injury (TCVI) is a rare and serious complication of traumatic brain injury (TBI). Various forms of TCVIs have been reported, including occlusions, arteriovenous fistulas, pseudoaneurysms, and transections. They can present at a variety of intervals after TBI and may manifest as sudden episodes, progressive symptoms, and even delayed fatal events. The purpose of this study was to analyze cases of TCVI identified at a single institution and further explore types and characteristics of these complications of TBI in order to improve recognition and treatment of these injuries.

METHODS

The authors performed a retrospective review of cases of TCVI identified at their institution between 2013 and 2016. A total of 5178 patients presented with TBI during this time period, and 42 of these patients qualified for a diagnosis of TCVI and had adequate medical and imaging records for analysis. Data from their cases were analyzed, and 3 illustrative cases are presented in detail.

RESULTS

The most common type of TCVI was arteriovenous fistula (86.4%), followed by pseudoaneurysm (11.9%), occlusion (2.4%), and transection (2.4%). The mortality rate of patients with TCVI was 7.1%.

CONCLUSIONS

The authors describe the clinical characteristics of patients with TCVI and provide data from a series of 42 cases. It is important to recognize TCVI in order to facilitate early diagnosis and treatment.

Neuroendovascular surgery

Neuroendovascular surgery and interventional neuroradiology both describe the catheter-based (most often) endovascular diagnosis and treatment of vascular lesions affecting the brain and spinal cord. This article traces the evolution of these techniques and their current role as the dominant and frequently standard approach for many of these conditions. The article also discusses the important changes that have been brought to bear on open cerebrovascular neurosurgery by neuroendovascular surgery and their effects on resident and fellow training and describes new concepts for clinical care.

Challenging dogma: report of a spinal cord arteriovenous malformation as an acquired lesion in a pediatric patient

Spinal cord intramedullary arteriovenous malformations (AVMs) have classically been considered congenital lesions that are present from birth. The reason for this dogmatic principal is the fact that a vast majority of these lesions present in pediatric and young adult patients. Interestingly, while many authors have demonstrated the development of de novo nidus-type brain AVMs, there have been no reported cases of a de novo intramedullary or perimedullary AVM of the spine. In this paper the authors describe what they believe to be the first reported case of a de novo AVM of the spinal cord in a young patient who underwent serial imaging from birth for evaluation of a syrinx. Potential pathophysiological mechanisms for the development of de novo vascular malformations of the spinal cord are discussed.

Use of ICG videoangiography and FLOW 800 analysis to identify the patient-specific venous circulation and predict the effect of venous sacrifice: a retrospective study of 172 patients

OBJECTIVE The best management of veins encountered during the neurosurgical approach is still a matter of debate. Even if venous sacrifice were to lead to devastating consequences, under certain circumstances, it might prove to be desirable, enlarging the surgical field or increasing the extent of resection in tumor surgery. In this study, the authors present a large series of patients with vascular or oncological entities, in which they used indocyanine green videoangiography (ICG-VA) with FLOW 800 analysis to study the patient-specific venous flow characteristics and the management workflow in cases in which a venous sacrifice was necessary. METHODS Between May 2011 and December 2017, 1972 patients were admitted to the authors' division for tumor and/or neurovascular surgery. They retrospectively reviewed all cases in which ICG-VA and FLOW 800 were used intraoperatively with a specific target in the venous angiographic phase or for the management of venous sacrifice, and whose surgical videos and FLOW 800 analysis were available. RESULTS A total of 296 ICG-VA and FLOW 800 studies were performed intraoperatively. In all cases, the venous structures were clearly identifiable and were described according to the flow direction and speed. The authors therefore defined different patterns of presentation: arterialized veins, thrombosed veins, fast-draining veins with anterograde flow, slow-draining veins with anterograde flow, and slow-draining veins with retrograde flow. In 16 cases we also performed a temporary clipping test to predict the effect of the venous sacrifice by the identification of potential collateral circulation. CONCLUSIONS ICG-VA and FLOW 800 analysis can provide complete and real-time intraoperative information regarding patient-specific venous drainage pattern and can guide the decision-making process regarding venous sacrifice, with a possible impact on reduction of surgical complications.

A review of extraaxial developmental venous anomalies of the brain involving dural venous flow or sinuses: persistent embryonic sinuses, sinus pericranii, venous varices or aneurysmal malformations, and enlarged emissary veins

This paper is a narrative review of extraaxial developmental venous anomalies (eDVAs) of the brain involving dural venous flow or sinuses: persistent embryonic sinuses, sinus pericranii, enlarged emissary veins, and venous varices or aneurysmal malformations. The article highlights the natural history, anatomy, embryology, imaging, clinical implications, and neurosurgical significance of these lesions, which the authors believe represent a continuum, with different entities characterized by distinct embryopathologic features. The indications and surgical management options are discussed for these individual intracranial pathologies with relevant illustrations, and a novel classification is proposed for persistent falcine sinus (PFS). The role of neurointervention and/or microsurgery in specific cases such as sinus pericranii and enlarged emissary veins of the skull is highlighted. A better understanding of the pathophysiology and developmental anatomy of these lesions can reduce treatment morbidity and mortality. Some patients, including those with vein of Galen malformations (VOGMs), can present with the added systemic morbidity of a high-output cardiac failure. Although VOGM is the most studied and classified of the above-mentioned eDVAs, the authors believe that grouping the former with the other venous anomalies/abnormalities listed above would enable the clinician to convey the exact morphophysiological configuration of these lesions, predict their natural history with respect to evolving venous hypertension or stroke, and extrapolate invaluable insights from VOGM treatment to the treatment of other eDVAs. In recent years, many of these symptomatic venous malformations have been treated with endovascular interventions, although these techniques are still being refined. The authors highlight the broad concept of eDVAs and hope that this work will serve as a basis for future studies investigating the role of evolving focal venous hypertension/global intracranial hypertension and possibilities of fetal surgical intervention in these cases.

Precipitating hydrophobic injectable liquid embolization of intracranial vascular shunts: initial experience and technical note

Precipitating hydrophobic injectable liquid is a new liquid embolic agent used mainly for intracranial neurointervention. The agent is ready to use (no shaking is required), since iodine, the radiopaque material, is covalently bonded into the compound. Additionally, due to the absence of tantalum, minimal artifacts are seen on postprocedure follow-up CT scans, and the agent penetrates into vessels smaller than 10 µm. The authors report their initial experience with the use of this agent in neurovascular intervention.

Reversible intracranial hypertension following treatment of an extracranial vascular malformation: case report

Pediatric hydrocephalus is a well-studied and still incompletely understood entity. One of the physiological means by which hydrocephalus and intracranial hypertension evolve is through perturbations to normal vascular dynamics. Here the authors report a unique case of an extracranial vascular anomaly resulting in persistently elevated intracranial pressures (ICPs) independent of CSF diversion in a patient with a Joubert syndrome-related disorder. The patient developed worsening intracranial hypertension after successful CSF diversion of Dandy-Walker malformation-associated hydrocephalus via endoscopic third ventriculostomy-choroid plexus cauterization (ETV/CPC). Vascular workup and imaging revealed an extracranial arteriovenous fistula of the superficial temporal artery at the site of a prior scalp intravenous catheter. Following microsurgical obliteration of the lesion, ICP normalized from > 30 cm H2O preoperatively to 11 cm H2O postoperatively. A repeat lumbar puncture at 4 months postoperatively again demonstrated normal pressure, and the patient remained asymptomatic for 9 months. Recurrent symptoms at 9 months were attributed to inadequate CSF diversion, and the patient underwent ventriculoperitoneal shunt placement. This is the first report of an extracranial-to-extracranial vascular anastomosis resulting in intracranial hypertension. This case report demonstrates the need to consider extracranial vascular anomalies as potential sources of persistently elevated ICP in the syndromic pediatric population.

Use of the Apollo detachable-tip microcatheter for endovascular embolization of arteriovenous malformations and arteriovenous fistulas

OBJECTIVE

Liquid embolic agents have revolutionized endovascular management of arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs). Nonetheless, since 2005, the US FDA has received more than 100 reports of microcatheter breakage or entrapment related to Onyx embolization, including 9 deaths. In 2014, the Apollo detachable-tip microcatheter became the first of its kind available in the US. Since then, few reports on its safety have been published.

METHODS

The authors conducted a retrospective review of endovascular cases by searching the patient databases at 2 tertiary cerebrovascular centers (Barrow Neurological Institute and University of Pittsburgh Medical Center). Patients who underwent endovascular embolization of an AVM or AVF using the Apollo microcatheter were identified. Patient demographics and lesion characteristics were collected. The authors analyzed Apollo-specific endovascular variables, such as number of microcatheterizations, sessions, and pedicles embolized; microcatheter tip detachment status; obliteration rate; and endovascular- and microcatheter-related morbidity and mortality.

RESULTS

From July 2014 to October 2016, a total of 177 embolizations using the Apollo microcatheter were performed in 61 patients (mean age 40.3 years). The most frequent presentation was hemorrhage (22/61, 36.1%). Most lesions were AVMs (51/61, 83.6%; mean diameter 30.6 mm). The mean Spetzler-Martin grade was 2.4. Thirty-nine (76.5%) of 51 patients with AVMs underwent resection. Microcatheterization was successful in 172 pedicles. Most patients (50/61, 82%) underwent a single embolization session. The mean number of pedicles per session was 2.5 (range 1-7). Onyx-18 was used in 103 (59.9%), N-butyl cyanoacrylate (NBCA) in 44 (25.6%), and Onyx-34 in 25 (14.5%) of the 172 embolizations. In 45.9% (28/61) of the patients, lesion obliteration of 75% or greater was achieved. Tip detachment occurred in 19.2% (33/172) of microcatheters. Fifty-three (86.9%) of the 61 patients who underwent embolization with the Apollo microcatheter had good functional outcomes (modified Rankin Scale score 0-2). No unintended microcatheter fractures or related morbidity was observed. One patient died of intraprocedural complications unrelated to microcatheter selection. In the univariate analysis, microcatheter tip detachment (p = 0.12), single embolized pedicles (p = 0.12), and smaller AVM nidus diameter (p = 0.17) correlated positively with high obliteration rates (> 90%). In the multivariate analysis, microcatheter tip detachment was the only independent variable associated with high obliteration rates (OR 9.5; p = 0.03).

CONCLUSIONS

The use of the Apollo detachable-tip microcatheter for embolization of AVMs and AVFs is associated with high rates of successful catheterization and obliteration and low rates of morbidity and mortality. The microcatheter was retrieved in all cases, even after prolonged injections in distal branch pedicles, often with significant reflux. This study represents the largest case series on the application of the Apollo microcatheter for neurointerventional procedures.

Orbital lymphatic-venous malformation with concomitant spontaneous orbital arteriovenous fistula: case report

The authors describe the case of an 11-year-old boy with no history of prior trauma, who experienced acute proptosis and visual loss while showering. Diagnostic carotid artery angiography revealed an orbital lymphatic-venous malformation (LVM) concomitant with an intraorbital arteriovenous fistula. The patient was treated with transvenous coil and N-butyl cyanoacrylate glue embolization, combined with direct percutaneous glue injection into the LVM followed by excision. There was good clinical and radiological response without recurrence at the 2-year follow-up. Diagnostic carotid angiography should be considered in cases of orbital LVM, as a concomitant arteriovenous fistula might be present in rare cases.

Cerebral hemorrhage in monozygotic twins with hereditary hemorrhagic telangiectasia: case report and hemorrhagic risk evaluation

The authors present a case of monozygotic twins with hereditary hemorrhagic telangiectasia (HHT) who experienced cerebral arteriovenous malformation (AVM) hemorrhage at a very young age. The clinical variables influencing HHT-related AVM rupture are discussed, and questions surrounding the timing of screening and intervention are explored. This is only the second known case of monozygotic HHT twins published in the medical literature, and the youngest pair of first-degree relatives to experience AVM-related cerebral hemorrhage. Evidence guiding the screening and management of familial HHT is lacking, and cases such as this underscore the need for objective and validated protocols.

Hydrocephalus in a patient with an unruptured pial arteriovenous fistula: hydrodynamic considerations, endovascular treatment, and clinical course

Intracranial pial arteriovenous fistulas, also known as nongalenic fistulas, are rare vascular malformations affecting predominantly the pediatric population. Hydrocephalus is an unusual presentation in which the exact pathophysiology is not fully understood. The aim of treatment in these cases is occlusion of the fistula prior to considering ventricular shunting. Here, the authors describe the hydrodynamic considerations of the paravascular pathway and the resolution of hydrocephalus with endovascular treatment of the fistula.

Clinical presentation and treatment outcomes of spinal epidural arteriovenous fistulas

OBJECTIVE Spinal epidural arteriovenous fistulas (SEDAVFs) constitute a rare but treatable cause of vascular myelopathy and are a different subtype from the more common Type I spinal dural AVFs. The purpose of this study was to review a consecutive series of SEDAVFs from a single institution and report on the clinical presentations, functional status, and treatment outcomes. METHODS The authors identified all SEDAVFs treated at their institution from 2005 to 2015. SEDAVFs were defined as spinal AVFs in which the fistulous connection occurred in the epidural venous plexus. The clinical presentation, functional status, immediate treatment outcomes, and long-term neurological outcomes were analyzed. RESULTS Twenty-four patients with SEDAVFs were included in this study. The patients' mean age at presentation was 66.9 years. The most common presenting symptoms were pain and numbness (22 patients, 91.7%), followed by lower-extremity weakness (21 patients, 87.5%). The mean duration of symptoms prior to diagnosis was 11.8 months. Eighteen patients (75.0%) were treated with endovascular therapy alone, 4 (16.7) with surgery, and 2 (8.3%) with a combination of techniques. There was 1 major treatment-related complication (4.2%). Fifteen patients (62.5%) had improvement in disability, and 12 patients (54.5%) had improvement in sensory symptoms. CONCLUSIONS SEDAVFs often present with lower-extremity motor dysfunction and sensory symptoms. With the availability of newer liquid embolic agents, these lesions can be effectively treated with endovascular techniques. Surgery is also effective at treating these lesions, especially in situations where endovascular embolization fails or is not safe and in patients presenting with mass effect from compressive varices.

C-2 arteriovenous fistula presenting as a pathologic hangman's fracture: case report

The authors report on an 81-year-old woman with a pathologic hangman's fracture secondary to a complex arteriovenous fistula (AVF). The patient presented with severe, unremitting neck pain and was found to have fractures bilaterally through the pars interarticularis of C-2 with significant anterior subluxation of C-2 over C-3 along with widening of the left transverse foramen. Due to an abnormally appearing left vertebral artery (VA) on CT angiography, the patient underwent conventional angiography, which revealed a complex AVF stemming from the left VA at the level of C-2 with dilated posterior cervical veins and a large venous varix. Given the radiographic evidence of bone remodeling and the chronicity of the AVF, it is believed that the C-2 vertebra was weakened over time by the pulsatile and compressive force of the vascular malformation eventually leading to fracture with minimal stress. Coil embolization of the AVF was performed followed by surgical fixation of C-1 to C-4. This case highlights the importance of investigating an underlying disease process in patients who present with significant spinal fractures in the absence of trauma.

Prevalence and characteristics of brain arteriovenous malformations in hereditary hemorrhagic telangiectasia: a systematic review and meta-analysis

OBJECTIVE Patients with hereditary hemorrhagic telangiectasia (HHT) are known to suffer from high rates of cerebral arteriovenous malformations (AVMs). The authors performed a systematic review and meta-analysis of the literature examining prevalence rates, characteristics, and clinical presentation of cerebral AVMs in the HHT population. METHODS To identify studies on AVM prevalence and characteristics in the HHT population, 4 databases (MEDLINE, EMBASE, Scopus and Web of Science) were searched by a reference librarian with over 30 years experience in systematic reviews and meta-analysis. The search period was January 1, 1990-March 2016. The following search terms were used: hereditary hemorrhagic telangiectasia, Osler-Weber-Rendu syndrome, AVM, brain AVM, arteriovenous malformation, arteriovenous fistula, prevalence, and epidemiology. The authors identified studies that examined the prevalence rates, characteristics, and clinical presentation of cerebral AVMs in patients with HHT. They assessed overall AVM prevalence rates as well as prevalence rates by age, sex, HHT type, and country/region. They also systematically reviewed the characteristics of AVMs, including rupture status, location, clinical presentation, angioarchitecture, and Spetzler-Martin grade. Data were analyzed using a random-effects meta-analysis model. RESULTS Thirty-nine studies were included in this meta-analysis. Thirty studies examined brain AVM prevalence rates in various HHT patient populations, and 18 studies examined AVM clinical and angiographic characteristics (9 studies examined both prevalence rates and AVM characteristics). The prevalence of brain AVMs in HHT patients was 10.4% (95% CI 7.9%-13.0%) with no significant difference between males (8.5%, 95% CI 4.9%-12.0%) and females (11.0%, 95% CI 5.9%-16.1%). Patients with HHT Type 1 (HHT1) had a significantly higher brain AVM prevalence (13.4%, 95% CI 9.5%-17.4%) compared with those with HHT Type 2 (HHT2) (2.4%, 95% CI 1.0%-3.8%) (p < 0.0001). In 55.2% (95% CI 38.3%-72.1%) of cases, the AVMs were symptomatic. Spetzler-Martin grade was 2 or less in 86.9% (95% CI 67.5%-95.2%) of patients. CONCLUSIONS The prevalence of brain AVMs in the HHT population is about 10%. HHT1 patients are significantly more likely to have brain AVMs than HHT2 patients. Most AVMs in the HHT population are symptomatic. The Spetzler-Martin grade for these lesions is 2 or less in nearly 90% of patients.

Transdural arterial recruitment to brain arteriovenous malformation: clinical and management implications in a prospective cohort series

OBJECTIVE The occurrence of transdural arterial recruitment (TDAR) in association with brain arteriovenous malformation (bAVM) is uncommon, and the reason for TDAR is not understood. The aim of this cohort study was to examine patient and bAVM characteristics associated with TDAR and the implications of TDAR on management. METHODS A prospective surgical database of bAVMs was examined. Cases previously treated elsewhere or incompletely examined by digital subtraction angiography (DSA) assessment were excluded. Three studies of this cohort were performed, as follows: characteristics associated with TDAR, the relationship between TDAR and neurological deficits unassociated with hemorrhage (NDUH), and the impact of TDAR on outcome from surgery. Regression models were performed. RESULTS Of 769 patients with complete DSA who had no previous treatment, 51 (6.6%) were found to have TDAR. The presence of TDAR was associated with increasing age (p < 0.01; OR 1.05; 95% CI 1.02-1.07); presentation with NDUH (p < 0.01; OR 2.71; 95% CI 1.29-5.71); increasing size of the bAVM (p < 0.01; OR 1.57; 95% CI 1.29-1.91); and combined supply from both anterior and posterior circulations (p = 0.02; OR 2.37; 95% CI 1.17-4.78). Further analysis of TDAR cases comparing those with and without NDUH found an association of larger size (6.6 cm [2.9 SD] compared with 4.7 cm [1.8 SD]; p < 0.01) and combined supply from both anterior and posterior circulations (relative risk 2.5; 95% CI 1.0-6.2; p = 0.04) to be associated with an NDUH presentation. For the 632 patients undergoing surgery there was an increased risk of complications (where this produced a new permanent neurological deficit at 12 months represented by a modified Rankin Scale score of > 1) with the following variables: size; location in eloquent brain; deep venous drainage; increasing age; and no presentation with hemorrhage. The presence of TDAR was not associated with an increased risk of complications from surgery. CONCLUSIONS The authors found that TDAR occurs in older patients with larger bAVMs, and that TDAR is also more likely to be associated with bAVMs presenting with NDUH. The likely explanation for the presence of TDAR is a secondary recruitment arising as a consequence of shear stress, rather than a primary vascular supply present from the earliest development of the bAVM.

The unusual presentation of a vascular injury after lumbar microdiscectomy: case report

Vascular injury during lumbar spine surgery is a relatively rare complication but can have devastating outcomes. The injury may not be apparent during surgery and can present acutely or late in various manners, and some injuries can be asymptomatic. This report discusses the unusual case of a 35-year-old woman who underwent a right L4-5 microdiscectomy for disc herniation and 4 days postoperatively presented with a pulmonary embolus. A subsequent CT scan revealed a pseudoaneurysm and arteriovenous fistula of the right common iliac vein and artery, which gave rise to the embolus. The patient received a right iliac artery stent, and at 4 months after surgery she continues to be symptom free. This report describes the atypical presentation of vascular injury after lumbar microdiscectomy and stresses the importance of cautiously using the pituitary rongeur when removing deeper disc fragments.

Safety of neuroangiography and embolization in children: complication analysis of 697 consecutive procedures in 394 patients

OBJECT

The safe treatment of children using catheter-based angiography and embolization poses unique challenges because of the technical factors regarding the size and fragility of access and target vessels, as well as unique pediatric cerebrovascular pathologies. The complication rates for neurointerventional procedures in children have not been established.

METHODS

The records of a consecutive cohort of pediatric patients who underwent neuroangiography and/or embolization between 2007 and 2013 were reviewed retrospectively to identify both intraprocedural and postprocedural complications. Demographic and clinical risk factors were analyzed with a multivariate logistic regression model.

RESULTS

The 697 consecutive procedures consisted of 429 diagnostic angiograms and 268 embolizations (mean age of patients 11.1 years; range 4 days to 18 years; 217 females). There were 130 intracranial, 122 extracranial, and 16 spinal embolizations. Pathologies included 28 intracranial arteriovenous malformations (AVMs), 12 spinal AVMs, 19 aneurysms, 29 vein of Galen malformations, 29 dural arteriovenous fistulas, 96 extracranial AVMs, 39 tumors, 3 strokes, and 13 others. Overall, 2 intraprocedural and 1 postprocedural complication (0.7%) occurred in the diagnostic group, all of which were nonneurological events. In the embolization group, 7 intraprocedural and 11 postprocedural complications (6.7%) were observed. Of these complications, 15 were nonneurological events (5.6%), 1 was a short-term neurological event (0.4%), and 2 were long-term neurological events (0.7%).

CONCLUSIONS

Neither the technical challenges posed by children's access and target vessels nor the unique neuro-vascular pathologies seen in children need result in an elevated morbidity rate related to neuroangiography and embolization. At a dedicated high-volume center, the complication rates may be lower than those for comparable procedures performed in adults.

Treatment of a cerebral pial arteriovenous fistula in a patient with sickle cell disease-related moyamoya syndrome: case report

Sickle cell disease (SCD) is an autosomal recessive hematological disorder, characterized by sickling of the red blood cells in response to a hypoxic stress and vaso-occlusive crises. It is associated with moyamoya-like changes on cerebral angiographic imaging in 43% of patients. Cerebral aneurysms, arteriovenous malformations, and dural arteriovenous fistulas (AVFs) have been described in association with SCD and moyamoya disease. However, the description of a pial AVF (pAVF) in a patient with SCD and/or moyamoya formation has not yet been reported. The authors present the case of a 15-year-old boy with SCD-associated moyamoya disease harboring a pAVF who developed a de novo venous aneurysm 8 months after undergoing indirect superficial temporal artery-middle cerebral artery (MCA) bypass that was complicated by bilateral ischemia of the MCA territory. The pAVF was successfully treated with transarterial embolization using Onyx. The authors describe the possible pathophysiological mechanisms and management strategies for this rare occurrence.

Multimodal treatment strategies for complex pediatric cerebral arteriovenous fistulas: contemporary case series at Barrow Neurological Institute

OBJECT Pediatric cerebral arteriovenous fistulas (AVFs) are rare but potentially lethal vascular lesions. Management strategies for these lesions have undergone considerable evolution in the last decade with the advent of new endovascular, surgical, and radiosurgical technologies. This study sought to review current treatment strategies and long-term clinical outcomes at a high-volume cerebrovascular institute. METHODS A retrospective chart review was performed on patients with a diagnosis of cerebral AVF from 1999 to 2012. Patients with carotid-cavernous fistulas, vein of Galen malformations, and age > 18 years were excluded from final analysis. Medical history, surgical and nonsurgical treatment, and clinical outcomes were documented. Pre- and postoperative angiograms were analyzed to assess for obliteration of the fistula. RESULTS Seventeen patients with pial AVFs (29.4%), dural AVFs (64.7%), or mixed pial/dural AVFs (5.9%) were identified. The majority of lesions were paramedian (70.6%) and supratentorial (76.5%). The study population had a mean age of 6.4 years, with a slight male predominance (52.9%), and the most common presenting symptoms were seizures (23.5%), headaches (17.6%), congestive heart failure (11.7%), and enlarging head circumference (11.7%). Among patients who underwent intervention (n = 16), 56.3% were treated with endovascular therapy alone, 6.3% were treated with open surgery alone, and 37.5% required a multimodal approach. Overall, 93.8% of the treated patients received endovascular treatment, 43.8% received open surgery, and 12.5% received radiosurgery. Endovascular embolysates included Onyx (n = 5), N-butyl cyanoacrylate (NBCA; n = 4), or coil embolization (n = 7) with or without balloon assistance (n = 2). Complete angiographic obliteration was achieved in 87.5% at the last follow-up evaluation (mean follow-up 3.1 years). One infant with incomplete AVF obliteration died of congestive heart failure, and 1 patient with complete obliteration died of acute sinus thrombosis, with an overall complication rate of 18.8%. CONCLUSIONS Pediatric cerebral AVFs are challenging neurosurgical lesions. Although advancements in endovascular therapy in the last decade have greatly changed the natural course of this disease, a multidisciplinary approach remains necessary for a large subset of patients. Surgeon experience with a thorough analysis of preoperative imaging is paramount to achieving acceptable clinical outcomes.

Large spinal intraosseous arteriovenous fistula: case report

Here the authors report the case of a fresh vertebral body fracture with a large spinal intraosseous arteriovenous fistula (AVF). A 74-year-old woman started to experience low-back pain following a rear-end car collision. Plain radiography showed diffuse idiopathic skeletal hyperostosis (DISH). Sagittal CT sections revealed a transverse fracture of the L-4 vertebral body with a bone defect. Sagittal fat-suppressed T2-weighted MRI revealed a flow void in the fractured vertebra. Spinal angiography revealed an intraosseous AVF with a feeder from the right L-4 segmental artery. A fresh fracture of the L-4 vertebral body with a spinal intraosseous AVF was diagnosed. Observation of a flow void in the vertebral body on fat-suppressed T2-weighted MRI was important for the diagnosis of the spinal intraosseous AVF. Because conservative treatment was ineffective, surgery was undertaken. The day before surgery, embolization through the right L-4 segmental artery was performed using 2 coils to achieve AVF closure. Posterolateral fusion with instrumentation at the T12-S2 vertebral levels was performed without L-4 vertebroplasty. The spinal intraosseous AVF had disappeared after 4 months. At 24 months after surgery, the bone defect was completely replaced by bone and the patient experienced no limitations in daily activities. Given their experience with the present case, the authors believe that performing vertebroplasty or anterior reconstruction may not be necessary in treating spinal intraosseous AVF.

Effectiveness of intraoperative indocyanine green videoangiography in direct surgical treatment of pediatric intracranial pial arteriovenous fistula

Intracranial pial arteriovenous fistulas (AVFs) are rare cerebrovascular lesions. The authors report a rare case of pediatric pial AVF treated by direct disconnection with the aid of indocyanine green (ICG) videoangiography. A 3-year-old girl presented with developmental problems. Magnetic resonance imaging revealed brain atrophy and an anomalous left temporal vascular mass. Angiography showed a high-flow pial AVF in the early arterial phase fed by the M1 portion of the left middle cerebral artery and draining into the superficial sylvian vein and the vein of Trolard with a large varix. Given that her fistula was located in a superficial region that was easily accessible by craniotomy, the authors successfully disconnected her pial AVF by direct surgery aided by ICG videoangiography, which clearly confirmed the shunting point. In this report, the authors discuss the existing literature and compare the relative merits of endovascular versus surgical options for the treatment of pial AVF.