Natural history, current concepts, classification, factors impacting endovascular therapy, and pathophysiology of cerebral and spinal dural arteriovenous fistulas

Congenital Intracranial Vascular Malformations in Children : Radiological Overview

Prompt medical attention is crucial for congenital intracranial vascular malformations in children and newborns due to potential severe outcomes. Imaging is pivotal for accurate identification, given the diverse risks and treatment strategies. This article aims to enhance the identification and understanding of congenital intracranial vascular abnormalities including arteriovenous malformation, arteriovenous fistula, cavernous malformation, capillary telangiectasia, developmental venous anomaly, and sinus pericranii in pediatric patients.

The Use of Intraoperative Microvascular Doppler in Vascular Neurosurgery: Rationale and Results-A Systematic Review

Surgical treatment of neurovascular lesions like intracranial aneurysms, arteriovenous malformations and arteriovenous dural fistulas is still associated with high morbidity. Several recent studies are providing increasing insights into reliable tools to improve surgery and reduce complications. Inadvertent vessel compromise and incomplete occlusion of the lesion represent the most possible complications in neurovascular surgery. It is clear that direct visual examination alone does not allow to identify all instances of vessel compromise. Various modalities, including angiography, microvascular Doppler and neurophysiological studies, have been utilized for hemodynamics of flow vessels in proper clipping of the aneurysm or complete obliteration of the lesion. We intended to review the current knowledge about the intraoperative microvascular Doppler (iMDS) employment in the most updated literature, and explore the most recent implications not only in intracranial aneurysms but also in neurovascular lesions like arteriovenous malformations (AVMs) and arteriovenous dural fistulas (AVDFs). According to the PRISMA guidelines, systematic research in the most updated platform was performed in order to provide a complete overview about iMDS employment in neurovascular surgery. Twelve articles were included in the present paper and analyzed according to specific research areas. iMDS employment could represent a crucial tool to improve surgery in neurovascular lesions. The safety and effectiveness of the surgical treatment of neurovascular lesions like intracranial aneurysm and other neurovascular lesions like AVMs and AVDFs requires careful and accurate consideration regarding the assessment of anatomy and blood flow. Prognosis may depend on suboptimal or incomplete exclusion of the lesion.

Endovascular Treatment of Dural Arteriovenous Fistulas in a Medium-Sized Scandinavian Neurovascular Center

BACKGROUND

Endovascular treatment is the primary treatment modality for dural arteriovenous fistulas (DAVFs). We performed a retrospective analysis of DAVFs treated in our hospital to determine if high-quality endovascular treatment can be provided in a medium-volume vascular center.

METHODS

From 2007 to 2021, 69 DAVF treatments were undertaken in our hospital. Of these DAVFs, 55 were endovascular, 11 were open surgical procedures, and 3 were Gamma Knife treatments. Of the endovascular treatments, 10 (18.2%) were in ruptured DAVFs. The most common location of endovascularly treated DAVFs was at the transverse/sigmoid sinus (32.7%) and at the cavernous sinus (25.5%). Of the endovascularly treated DAVFs, 38.2% were low-grade fistulas (Cognard I/IIa), whereas 61.8% were high-grade fistulas (Cognard ≥IIb). 58.2% of fistulas were treated transarterially. DAVFs located in the cavernous sinus were treated using coils alone, whereas most other DAVFs were treated with liquid embolics alone or in combination with coils.

RESULTS

Complete or near-complete cure was achieved in 74.5% of treatments, whereas 18.2% of treatments resulted in downgrading of the fistula. Twelve patients were retreated once (9 endovascularly) and 1 patient was retreated twice. After retreatment, complete or near-complete cure was achieved in 86.4% of patients. 72.7% of treatments were performed without any remnant or retreatment. There were no procedure-related deaths. One patient experienced a complication resulting in permanent neurologic deficits. Seven other complications (12.7%) were recorded, all asymptomatic or causing only temporary symptoms.

CONCLUSIONS

Based on our findings, we conclude that high-quality treatment of DAVFs can be provided in a medium-volume vascular center.

Comparison of Intraoperative Indocyanine Green Videoangiography vs Postoperative Catheter Angiography to Confirm Microsurgical Occlusion of Spinal Dorsal Intradural Arteriovenous Fistulas

BACKGROUND

Dorsal intradural arteriovenous fistulas (DI-AVFs) represent 80% of spinal AVFs. Microsurgical clip occlusion is a durable treatment that uses preoperative and postoperative digital subtraction angiography (DSA) as standard practice. Intraoperative indocyanine green videoangiography (ICG-VA) is a valuable intraoperative adjunct in these cases. Intraoperative ICG-VA findings have not been compared with postoperative DSA findings.

OBJECTIVE

To assess the diagnostic value of intraoperative ICG-VA vs postoperative DSA for spinal DI-AVFs.

METHODS

A multi-institutional database of vascular malformations was queried for all surgically managed cases of DI-AVF. Patients with both intraoperative ICG-VA and postoperative DSA were included. Demographic and radiologic data, intraoperative findings, and surgical outcomes data were retrospectively analyzed.

RESULTS

Forty-five patients with DI-AVF were identified (male sex, 32; mean age, 61.9 [range, 26-85] years). All DI-AVFs were treated with interruption of the fistula with clip occlusion of the draining vein. Intraoperative ICG-VA showed complete obliteration in all patients. Postoperative DSA was performed for 40 patients and confirmed complete obliteration in all patients. The negative predictive value of ICG-VA confirming complete occlusion of the DI-AVFs was 100%. Eighteen patients (47%) experienced clinical improvement, and 16 (42%) experienced no change in condition.

CONCLUSION

ICG-VA is useful for intraoperative identification of DI-AVFs and confirmation of complete microsurgical occlusion. Correlation between intraoperative ICG-VA and postoperative DSA findings demonstrates the diagnostic power of ICG-VA. This finding suggests that postoperative DSA is unnecessary when intraoperative ICG-VA confirms complete occlusion of the DI-AVF, which will spare patients the procedural risk and cost of this invasive procedure.

Pathophysiology and classification of intracranial and spinal dural AVF

Dural arteriovenous fistulas (DAVFs) are pathologic shunts between pachymeningeal arteries and dural venous channel. DAVFs are relatively rare, however, DAVFs can lead to significant morbidity and mortality due to intracranial hemorrhage and non-hemorrhagic neurologic deterioration related to leptomeningeal venous drainage. The etiology and pathophysiology of DAVFs is not fully understood. Several hypotheses for development of DAVF and classifications for predicting risk of hemorrhage and neurological deficit have been proposed to help clinical decision making according to its natural history. Herein, incidence, etiology, pathophysiology of development of intracranial and spinal DAVF including their classifications are briefly described with short historical review.

Transradial Approach for Thoracolumbar Spinal Angiography and Tumor Embolization: Feasibility and Technical Considerations

The transradial approach (TRA) is an effective and safe alternative to transfemoral access for diagnostic neuroangiography and craniocervical interventions. While the technical aspects of supraclavicular intervention are well-described, there are little data on the TRA for thoracolumbar angiography and intervention. The authors describe the feasibility of the TRA for preoperative thoracic tumor embolization, emphasizing technique, device selection, navigation, and catheterization of thoracolumbar segmental arteries. This approach extends the benefits of TRA to spinal interventional neuroradiology.

Spinal vascular lesions: anatomy, imaging techniques and treatment

•

Vascular myelopathies include different aetiology and mechanism of damage.

•

The level of the lesion and the localization within the SC correlates with the clinical symptoms.

•

CT, MRI and angiography are essential for diagnosis and treatment playing a complementary role.

•

MRI is the gold standard for the evaluation of spinal cord lesions.

•

Spinal angiography is the gold standard for evaluation of spinal cord vasculature and vascular malformations.

Background

Vascular lesions of the spinal cord are rare but potentially devastating conditions whose accurate recognition critically determines the clinical outcome. Several conditions lead to myelopathy due to either arterial ischemia, venous congestion or bleeding within the cord. The clinical presentation varies, according with the different aetiology and mechanism of damage.

Purpose

The aim is to provide a comprehensive review on the radiological features of the most common vascular myelopathies, passing through the knowledge of the vascular spinal anatomy and the clinical aspects of the different aetiologies, which is crucial to promptly address the diagnosis and the radiological assessment.

Superficial middle temporal vein as a pivotal route to embolize dural carotid-cavernous fistulas

Dural carotid-cavernous fistulas (DCCF) are located in the cavernous sinus wall involving the arterial feeders from the external and internal carotid arteries. The venous route usually passes through the internal jugular vein and inferior petrosal sinus (IPS) up to the pathologic shunts of the cavernous sinus. In cases of a thrombosed IPS, catheterization is not always possible because of the obstruction. Here, we report eight cases of DCCF treated with endovascular transvenous embolization via the superficial middle temporal vein (SMTV). A retrospective study involving eight patients with DCCF treated with transvenous embolization via SMTV was performed. In six patients, IPS was thrombosed. In one patient, IPS was patent, but we could not catheterize the internal jugular vein. In the other patient, because of the compartmentalization of the cavernous sinus, we could not access the anterior part of the cavernous sinus via IPS. Therefore, we performed the embolization via SMTV to occlude the shunts of the anterior part of the cavernous sinus. In all eight cases, navigating through the tortuous junction of the angular vein and superior ophthalmic vein (SOV) was possible. After transvenous catheterization of the cavernous sinus via SMTV, placement of coils resulted in complete occlusion of DCCF with clinical improvement in all eight patients. In the endovascular treatment of DCCF, the transfemoral approach via SMTV provides a pivotal route alternative to other transvenous routes. In patients with dilated SOV, catheterization of the cavernous sinus via SMTV is usually successful.

Far Lateral Approach for Disconnection of Craniocervical Junction Dural Arteriovenous Fistula Presented with Myelopathy and Hydrocephalus

We report a case of craniocervical junction dural arteriovenous fistula (dAVF) presented with myelopathy and normal pressure hydrocephalus, and was treated with hybrid approach of embolization and surgical disconnection. A 68-year-old gentleman presented with 1 year history of unsteady gait and sphincter disturbance. Magnetic resonance imaging (MRI) showed abnormally enlarged and tortuous vessels over right cerebellomedullary cistern. Digital subtraction angiogram (DSA) showed Cognard's type-V dAVF at craniocervical junction. Catheter embolization was performed via external carotid artery and finally surgical disconnection was done with far lateral approach ( Fig. 1 ). Postoperative DSA showed no more arteriovenous shunting ( Fig. 2 ). Clinically the patient improved after a course of rehabilitation. Dural AVF at craniocervical junction is rare and its clinical presentation can be highly variable from subarachnoid hemorrhage to brainstem dysfunction. Identification of the exact fistula site is essential in surgical planning. Surgery is effective and safe to achieve complete obliteration and good clinical outcome. 123456

The link to the video can be found at: https://youtu.be/xI48stSlWpY .

Efficiency of Endovascular Therapy for Bilateral Cavernous Sinus Dural Arteriovenous Fistula

BACKGROUND

The principles of endovascular treatment of bilateral cavernous sinus dural arteriovenous fistula (CS-dAVF) are not well established because of the complexity in the number of fistula tracts and their behavior, which seems to be more aggressive. We aimed to determine an efficient technique for endovascular treatment of bilateral CS-dAVF and the associated factors to achieve good clinical and angiographic outcomes.

METHODS

The data were analyzed from 165 consecutive patients diagnosed with CS-dAVF from January 2005 to September 2018. The demographic data included approaching route, embolization times, embolization material, sequence of embolization, number of embolization sessions, and angiographic and clinical outcomes. Interrater agreement of bilateral CS-dAVF diagnosis was performed using the κ coefficient. The factors associated with treatment outcome were analyzed using a Pearson χ² test.

RESULTS

Bilateral CS-dAVF was detected in 43 patients (26%). Angiographic presentations that showed evidence of sinus thrombosis, dangerous venous drainage, and higher Satomi classification were more commonly found in bilateral CS-dAVF than in unilateral CS-dAVF. Good clinical outcome and cure from angiography were obtained in 90% and 74%, respectively. Ipsilateral inferior petrosal sinus-intercavernous sinus-contralateral cavernous sinus catheterization was the major approach route of treatment. The factors associated with improved clinical outcome were transvenous approach, shunt closure, coil embolization, and sequencing the embolization (P < 0.001).

CONCLUSIONS

Dangerous venous drainage tends to increase in bilateral CS-dAVF. Retrograde ipsilateral inferior petrosal sinus catheterization using coil embolization and sequencing the embolization are the major concerns for treatment.

Peculiar Characteristics of Arteriovenous Malformations Arising in the Galenic Region

Arteriovenous malformations (AVM) are congenital vascular lesions fed by arterial feeders originating from branches of the internal carotid artery (ICA) or vertebrobasilar artery. We experienced unique AVMs arising in the midline Galenic region, receiving blood supply from the ICA/vertebral artery systems and the external carotid artery system. We retrospectively reviewed data on eight patients who had an AVM arising in the Galenic region and were treated in the University of Tokyo Hospital between 1990 and 2019. The median age at diagnosis was 62 years. Three cases (38%) presented with obstructive hydrocephalus due to aqueduct obstruction caused by an engorged vein of Galen. In all cases, feeders from dural arteries were present and the vein of Galen was the primary drainer. All patients underwent stereotactic radiosurgery. Five patients were followed for > two years; nidus obliteration was confirmed in one, and > 75% shrinkage was confirmed in three, while one patient died due to hemorrhage. Altogether, AVMs arising in the Galenic region are rare and exhibit several peculiar characteristics including the presence of dural feeders, an older age at presentation and presentation with obstructive hydrocephalus.

Concomitant Sacral Dural Arteriovenous Fistula and Conus Medullaris Arteriovenous Malformation with Respective Drainage Veins: Case Report and Literature Review

BACKGROUND

Spinal dural arteriovenous fistulas (DAVFs) and spinal arteriovenous malformations (AVMs) are relatively rare. Moreover, multiple spinal cord vascular lesions in an individual, such as double DAVFs and DAVF with AVM, are extremely rare. To date, there are only several reported cases of concomitant spinal DAVFs and AVMs.

CASE DESCRIPTION

A 25-year-old woman presented with pain of the right lower limb persisting for 1 month. Spinal magnetic resonance imaging showed prominent signal flow voids in the lumbosacral canal. Spinal digital subtraction angiography (DSA) showed a sacral DAVF fed by the right lateral sacral artery and a spinal intradural AVM at the conus medullaris fed by the anterior spinal artery from the left T11 intercostal artery. The drainage veins in these 2 lesions were respective and without common anastomosis. The diagnosis of concomitant sacral DAVF and conus AVM was made. Microsurgery was performed to excise these lesions successfully in the same operation. The patient's symptoms gradually improved after surgery. Postoperative spinal DSA confirmed the complete disappearance of the 2 lesions.

CONCLUSIONS

The concomitant presence of sacral DAVF and conus AVM is extremely rare. Nonetheless, clinicians should be aware of the possibility of the coexistence of multiple types of spinal vascular lesions in a single patient.

[Dural arteriovenous fistula causing complex visual hallucinations without an anopsia]

We report the case of a 76-year-old woman who presented with recurrent episodes of complex visual hallucinations in her right visual field without an anopsia. The electroencephalogram showed sharp transients in the left parietotemporal region with phase reversals at T5 and P3. FLAIR MRI revealed hyperintense lesions in the left temporo-occipital lobe, located mainly in the left inferior temporal lobe. Cerebral angiography revealed an arteriovenous shunt from the left occipital artery to the left transverse sinus with cortical venous reflux. The complex visual hallucinations were resolved after transarterial embolization. We therefore hypothesize that this patient's complex visual hallucinations were caused by epileptic seizures or changes in cortical blood flow caused by the cortical venous reflux from the arteriovenous fistula. In general, epileptic hallucinations expand into the bilateral visual field. We reveal that in rare cases, complex visual hallucinations can also be limited to the unilateral visual field without an anopsia. Additionally, we reveal that a dural arteriovenous fistula can cause visual hallucinations without hemianopia.

Primary conus medullaris arteriovenous shunt and secondary lumbo-sacral epidural arteriovenous fistula: One malformation can hide another

We report an anatomical-based association between conus medullaris pial arteriovenous shunt that drain caudally towards the lumbosacral area with very delayed onset of an acquired lumbar epidural shunt, draining secondarily towards intradural veins and responsible for a venous congestive myelopathy with identical clinical symptoms. These patients require close clinical and imaging follow-ups in order to propose adequate treatments before onset of irreversible neurological deficits. MRA should include the lumbo-sacral area in its field of view.

Tips and tricks in the diagnosis of intracranial dural arteriovenous fistulas: A pictorial review

Dural arteriovenous fistulas (DAVFs) are complex vascular abnormalities that account for 10-15% of intracranial vascular malformations. DAVFs are typically encountered in middle-aged adults, with a slightly female predominance. The causative factors are still uncertain; however, abnormal local hemodynamics and neoangiogenesis related to dural sinus or venous thrombosis can contribute to DAVF occurrence. The diagnosis is dependent on a high level of clinical suspicion and high-resolution imaging techniques. Computed tomography and/or magnetic resonance imaging aid in the diagnosis, but conventional angiography remains the most accurate method for the complete characterization and classification of DAVFs. The therapeutic approach can be conservative or more aggressive, based on symptom severity, sequelae risk and patient characteristics. This article is a pictorial review of adult intracranial DAVFs that highlights some tips and tricks for recognizing useful red flags in the suspicion of DAVFs.

Dural Arteriovenous Fistulas with Perimedullary Venous Drainage Successfully Managed Via Endovascular Electrocoagulation

BACKGROUND

Dural arteriovenous fistulas (DAVFs) with perimedullary venous drainage are very rare intracranial DAVFs. Treating DAVF via an endovascular electrocoagulation technique, to the best of our knowledge, has not been reported in the literature. We therefore report the first successful case.

CASE DESCRIPTION

We report a rare case of Cognard type V DAVF. The feeding arteries were the middle meningeal artery, the recurrent meningeal branch of ophthalmic artery, and the meningohypophyseal trunk. The patient presented with paresthesia and weakness in the lower limbs. T2-weighted magnetic resonance imaging revealed a high signal in the medulla oblongata and upper cervical spinal cord. Our first procedure via the middle meningeal artery with Onyx 18 (ev3 Neurovascular) as the embolization agent failed to occlude the fistula. We finally occluded the fistula with the endovascular electro-coagulation technique. Two-year follow-up revealed total disappearance of the fistula and relieve of patient's symptoms.

CONCLUSIONS

The endovascular electrocoagulation technique is very effective in the management of complex DAVFs with perimedullary venous drainage.

An Isolated Unilateral Pontomedullary Lesion Due to An Intracranial Dural Arteriovenous Fistula Mimicking A Brain Tumor - Case and Review

Intracranial dural arteriovenous fistula (DAVF) with perimedullary venous drainage may cause brainstem swelling and represent a diagnostic challenge. A 66-year-old man presented to the emergency room with recurrent vertigo, minimal truncal ataxia with a wide-based gait, and a slightly impaired tandem gait. Brain magnetic resonance imaging (MRI) revealed a hyperintense lesion in the left pontomedullary area on T2-weighted images (T2WIs) with partial gadolinium enhancement, but without increased signals on diffusion-weighted images. Abnormal serpentine flow void vessels surrounding the medulla and upper cervical spinal cord were initially overlooked but discovered later. An angiogram revealed DAVF with feeders from the right occipital artery and the meningeal branch of the right distal vertebral artery with drainage into the anterior medullary venous system and the perimedullary veins. The patient underwent a successful transarterial endovascular embolization and improved gradually. A brain MRI at 3-month follow-up revealed a residual hyperintense signal on the T2WIs in the left lower medulla. Six cases of patients exhibiting DAVF with isolated unilateral brainstem swelling from the literature were reviewed. Isolated unilateral brainstem swelling due to intracranial DAVF with perimedullary venous drainage is extremely rare and might mimic a tumor on MRI. Abnormal serpentine flow void vessels on the surface of the brainstem or spinal cord are crucial diagnostic clues.

Use of a New Indocyanine Green Pooling Technique for Improved Visualization of Spinal Dural AV Fistula: A Single-Center Case Series

BACKGROUND

Intraoperative indocyanine green video angiography (ICG-VAG) is a useful tool in cerebral vascular surgery. In spinal procedures such as dural arteriovenous (AV) fistula, use of ICG-VAG is limited due to lower perfusion pressure. Therefore, we developed a new pooling technique with adapted workflow to improve intraoperative visualization.

METHODS

Patients operated on spinal dural AV fistulas using ICG-VAG were prospectively included. A new workflow for ICG-VAG was applied: 1) temporary clip placement at the suspected fistula point, 2) ICG administration during 100% oxygenation, 3) ICG pooling proximal of temporary clip, 4) clip removal/observation of vascular filling. Case records, clinical data, magnetic resonance imaging, digital subtraction angiography (DSA), and clinical outcome were analyzed retrospectively.

RESULTS

A total of 11 patients (median age 68 years, average course of disease 15 months) were included. Optimized, inverted workflow resulted in considerable pooling of ICG in the supplying feeder of the AV fistula in all cases. Complete obliteration was confirmed in 10 of 11 patients by postoperative DSA. However, 1 patient had an additional, preoperative radiologically undetected small feeder that enlarged until postoperative DSA and made successful reoperation necessary. After the median follow-up of 33.2 months, the Aminoff-Logue scale was decreased in all patients, and the McCormick score (modified Rankin score) was improved in 9 (8) patients and remained stable in 2 (3) patients.

CONCLUSIONS

Procedure modification in terms of ICG pooling enabled us to detect more easily the pathologic vascular architecture. ICG-VAG is a useful adjunct in the surgical treatment of spinal dural AV fistula because it is a real-time, noninvasive, and radiation-free technique with adequate image resolution.

Endovascular Treatment of a Dural Arteriovenous Fistula after Cerebral Sinovenous Thrombosis in a Child

BACKGROUND

Dural arteriovenous fistula (DAVF) is rare in children. Development theories postulate a response to cerebral sinovenous thrombosis (CSVT) or to venous hypertension. The symptoms are highly nonspecific and depend on lesion location. Standard treatment of thrombosis is based on antithrombotic therapy, while the main therapy for DAVF is embolization.

CASE REPORT

An 8-year-old boy presented with headache was diagnosed with CSVT and treated with anticoagulant. He developed tinnitus, mental confusion, and lowering of consciousness. Magnetic resonance imaging showed a DAVF draining through a single stenotic venous sinus. Successful endovascular treatment was performed with arterial embolization of multiple feeders and stent and balloon sinus angioplasty.

CONCLUSION

Risk factors associated with sinus thrombosis must be always investigated; endovascular treatment is safe and reasonable in a clinical deterioration scenario.

Indocyanine Green Videoangiography in the Surgical Treatment of Spinal Dural Arterovenous Fistula: A Useful Application

BACKGROUND

Indocyanine green videoangiography (ICG-V) is used with increasing frequency in neurovascular surgery. ICG-V use in spinal dural arteriovenous fistulas (DAVFs) allows visualization of the hemodynamics of the fistula and to confirm its exclusion after ligation of the feeder. Here, we illustrate how ICG-V is useful for centering the surgical exposure during mini-invasive approaches to spinal DAVFs.

METHODS

An overweight 66-year-old woman with progressive paraparesis and sphincter disturbances underwent treatment for a spinal DAVF fed by the left T6 radicular artery. After intraoperative fluoroscopy, T6 hemilaminectomy was performed. Because of slight misplacement of the bone opening, the feeder was not visible at the dural opening. We placed a temporary clip on a perimedullary arterialized vein and performed ICG-V while removing the clip.

RESULTS

Reviewing the video clip and analyzing the direction of ICG flow inside the perimedullary venous plexus allowed us to locate the fistula with respect to the bone window and to extend the laminectomy in the correct direction.

CONCLUSIONS

IGC-V can be helpful in mini-invasive approaches to spinal DAVFs to recalibrate the bone opening after misplacement of the initial hemilaminectomy.

De novo aneurysm formation of a feeder artery after embolization of a dural arteriovenous fistula and rupture during second embolization

Objective Hemorrhage during embolization of dural arteriovenous fistula (DAVF) is a rare but devastating complication. This study was undertaken to analyze the causes of hemorrhage and avoid complication. Methods The clinical data of a case of DAVF with hemorrhagic complication were retrospectively collected and analyzed. Results The patient in this case presented with DAVF and two de novo aneurysms of a feeder artery after the first embolization. One de novo aneurysm ruptured during the second embolization of the DAVF because of hemodynamic change. Computed tomography showed a subdural hematoma, and surgical exploration was emergently performed. However, the patient died at postoperative day 10. Conclusions De novo aneurysm of a feeder artery may form after embolization of DAVF because of hemodynamic change. It has a high risk of rupture and should be a primary consideration in embolization of DAVF.

Polymorphism in dural arteriovenous fistula: matrix metalloproteinase-2-1306 C/T as a potential risk factor for sinus thrombosis

Essentials Sinus thrombosis may play a crucial role in development of dural arteriovenous fistula (DAVF). Little is known about the association between gene polymorphism and the development of DAVF. MMP-2-1306 C/T showed a higher prevalence rate in DAVF cases with sinus thrombosis. MMP-2-1306C/T polymorphism is likely a potential risk factor for sinus thrombosis in DAVF.

SUMMARY

Background Dural arteriovenous fistula (DAVF) is a rare but important cerebrovascular disorder in adults. Little is known about the molecular genetic pathogenesis underlying DAVF development. Objectives To investigate the associations of gene polymorphisms and DAVF. Materials and Methods By the use of real-time PCR genotyping, seven single-nucleotide polymorphisms (SNPs) of angiogenesis-related genes were analyzed in 72 DAVF patients. Pertinent clinical and imaging data were subgrouped on the basis of location (cavernous sinus versus lateral sinus), lesions (single versus multiple), cerebral venous reflux (CVR) grading (Borden I versus Borden II/III), and sinus thrombosis (with versus without). Results We found that individuals carrying the polymorphic allele of matrix metalloproteinase (MMP)-2-1306 C/T (rs243865) had a significantly increased risk of sinus thrombosis in DAVF (odds ratio 6.2; 95% confidence interval 1.7-22.9). There was a weak difference in associations of tissue inhibitor of metalloproteinase (TIMP)-2 (rs2277698) gene polymorphism and DAVF patients subgrouped by CVR grading. Conclusions These preliminary results indicate that MMP-2-1306 C/T, but not MMP-9, TIMP-1, TIMP-2, and vascular endothelial growth factor A SNP variants, is a risk factor for the development of sinus thrombosis in DAVF patients.

Lessons to Be Remembered from a Dural Arteriovenous Fistula Mimicking Medulla and High Cervical Cord Glioma

The radiological signs of intracranial dural arteriovenous fistulas (ICDAVFs) are heterogenous. While it is commonly accepted that hyper intense T2 wedge magnetic resonance imaging of the brainstem and cervical cord mainly concern gliomas, it is so far uncommon and probably unknown that ICDAVFs can imitate similar radiological pattern, especially with gadolinium contrast enhancement and cord enlargement. Thus the angiography is poorly documented in the diagnostic workup. We report the unusual history of ICDAVFs, revealed by clinical and radiological features that mimicked a medulla or cervical spinal cord glioma. This observation provides information on the management of atypical lesions mimicking medulla or cervical cord glioma and arguments for a careful radiological study. Looking for dilated veins around the brainstem and the cord is mandatory in the workup of a supposed infiltrating brainstem or spinal cord lesion, in order to rule out an ICDAVF. Even if the hyperintense T2 images associated with contrast enhancement is in favor of a brainstem or spinal cord glioma, additional cerebral angiography should be mandatory. Moreover, this clinical case highlights the need for a multidisciplinary approach including neuroradiologist, oncologist and neurosurgeon.

Endovascular Treatment of Bilateral Cavernous Sinus Dural Arteriovenous Fistula: Therapeutic Strategy and Follow-Up Outcomes

Objective

Bilateral cavernous sinus dural arteriovenous fistula (CSdAVF) is very rare, even in Asian countries. The research intended to present clinical and radiologic outcomes of treating such fistulas through endovascular embolization.

Materials and Methods

Data was obtained from 220 consecutive patients, with CSdAVF, who were treated from January 2004 to December 2015. Bilateral CSdAVF was identified in 17 patients (7.7%). The clinical and radiologic outcomes of the fistulas were assessed with an emphasis on the technical aspects of treatment.

Results

At the time of treatment, 7 and 10 patients presented with bilateral and unilateral symptoms, respectively. In the former cases, 4 patients had progressed from unilateral to bilateral symptoms. Bilateral fistulas were treated with a single-stage transvenous embolization (TVE) in 15 patients, via bilateral inferior petrosal sinuses (IPS) (n = 9) and unilateral IPS (n = 6). In the other 2 patients with one-sided dominance of shunting, only dominant fistula was treated. Two untreated lesions were found on follow-up to have spontaneously resolved after treatment of the dominant contralateral fistula. Of the 34 CSdAVF lesions, complete occlusion was achieved in 32 lesions after TVE. Seven patients (41.2%) developed worsening of cranial nerve palsy after TVE. During the follow-up period, 4 patients obtained complete recovery, whereas the other 3 remained with deficits.

Conclusion

With adjustments of endovascular procedures to accommodate distinct anatomical configurations, endovascular treatment for bilateral CSdAVF can achieve excellent angiographic occlusion results. However, aggravation of symptoms after TVE may occur frequently in bilateral CSdAVF. In the patients with one-sided dominance of shunt, treatment of only dominant fistula might be an alternative option.

Concomitant conus medullaris arteriovenous shunts and sacral dural arteriovenous fistulas: pathophysiological links related to the venous drainage of the lesions in a series of five cases

Background

Spinal cord arteriovenous shunts (scAVSs) are a group of lesions located in the spinal cord itself or in the surrounding structures. The most common scAVSs are spinal dural arteriovenous fistulas (sDAVFs), which are acquired lesions. The pathogenesis of sDAVFs involves thrombosis and venous hypertension as trigger factors. Intradural scAVSs such as spinal cord arteriovenous nidus type malformations (AVMs) and pial arteriovenous fistulas are less common than sDAVFs and are considered to have a so-called ‘congenital’ origin. The association between different concomitant scAVSs is very rare and the association of sDAVFs with intradural scAVSs has been described in only a few case reports.

Methods

We describe a case series of five patients presenting with a conus medullaris AVS associated with a lower lumbar or sacral DAVF.

Results

Three of our patients were <30 years old at presentation. In four of these five cases the intradural scAVS drained caudally, engorging the epidural plexus in the same location as the sDAVF. In only one case, who presented with thrombosis of the drainage of the main compartment of a conus medullaris pial AVF, was the location of the DAVF opposite to the location of the residual drainage.

Conclusion

We discuss the pathophysiological link between scAVS and sDAVF on the basis of the rarity of the DAVF, the uncommon association between scAVS and sDAVF, the presence of sDAVF in young patients, and the venous hypertension created by the venous drainage towards the sacral area responsible for angiogenesis creating the dural shunt.

Evolutionary History of Multiple Dural Fistula

Intracranial dural arteriovenous fistulas (DAVFs) are abnormal communications between arteries and veins or dural venous sinuses, which sit between the sheets of the dura. They represent 10% to 15% of intracranial vascular malformations. Clinical manifestations and prognosis depend on the pattern of venous drainage and location. The clinical presentation of DAVF may be mistaken for vascular or nonvascular brain pathologies. For that reason, within the differential diagnosis come a wide range of conditions, such as secondary headaches, encephalopathies, dementias including those with rapid progression, neurodegenerative diseases, inflammatory processes, or tumors typically at the orbital level or in the cavernous sinus. Diagnosis requires a high degree of suspicion because of the multiplicity of symptoms and presentations, making this pathology an entity that provides a major challenge for clinicians, yet early and multidisciplinary treatment of high-grade fistulas improve the possibility of avoiding poor or unfavorable outcomes for the patient.

Angio-Architectural Features of High-Grade Intracranial Dural Arteriovenous Fistulas: Correlation With Aggressive Clinical Presentation and Hemorrhagic Risk

BACKGROUND: High-grade dural arteriovenous fistulas (dAVFs) can present shunts with very different angio-architectural characteristics. Specific hemodynamic factors may affect clinical history and determine very different clinical courses.

OBJECTIVES: To evaluate the relationship between some venous angio-architectural features in high-grade dAVFs and clinical presentation. Specific indicators of moderate or severe venous hypertension were analyzed, such as altered configurations of the dural sinuses (by a single or a dual thrombosis), or overload of cortical vessels (restrictions of outflow, pseudophlebitic cortical vessels, and venous aneurysms).

METHODS: The institutional series was retrospectively reviewed (49 cases), and the pattern of venous drainage was analyzed in relationship with clinical presentation (benign/aggressive/hemorrhage).

RESULTS: Thirty-five of 49 cases displayed cortical reflux (high-grade dAVFs). This subgroup displayed a benign presentation in 31.42% of cases, an aggressive in 31.42%, and hemorrhage in 37.14%.

CONCLUSIONS: Our data confirm that within high-grade dAVFs, 2 distinct subpopulations exist according to severity of clinical presentation. Some indicators we examined showed correlation with aggressive nonhemorrhagic manifestations (outflow restriction and pseudophlebitic cortical vessels), while other showed a correlation with hemorrhage (dual thrombosis and venous aneurysms). Current classifications appear insufficient to identify a wide range of conditions that ultimately determine the organization of the cortical venous drainage. Intermediate degrees of venous congestion correlate better with the clinical risk than the simple definition of cortical reflux. The angiographic aspects of venous drainage presented in this study may prove useful to assess dAVF hemodynamic characteristics and identify conditions at higher clinical risk.

Imaging of Intracranial Hemorrhage

Intracranial hemorrhage is common and is caused by diverse pathology, including trauma, hypertension, cerebral amyloid angiopathy, hemorrhagic conversion of ischemic infarction, cerebral aneurysms, cerebral arteriovenous malformations, dural arteriovenous fistula, vasculitis, and venous sinus thrombosis, among other causes. Neuroimaging is essential for the treating physician to identify the cause of hemorrhage and to understand the location and severity of hemorrhage, the risk of impending cerebral injury, and to guide often emergent patient treatment. We review CT and MRI evaluation of intracranial hemorrhage with the goal of providing a broad overview of the diverse causes and varied appearances of intracranial hemorrhage.

Transvenous microguidewire looping technique for breach of ipsilateral inferior petrosal sinus occlusions en route to cavernous sinus dural arteriovenous fistulas

BACKGROUND AND PURPOSE

Transarterial access to dural arteriovenous fistulas (dAVFs) has been popularized by device improvements and novel embolic materials. However, this approach is limited in the cavernous sinus (CS) because of related complications and low cure rates. Although a transvenous approach, via ipsilateral inferior petrosal sinus (IPS), may be more suitable for CS-dAVFs, microcatheter delivery is occasionally impeded by ipsilateral IPS occlusion. Described herein is a microguidewire looping method to breach such occlusions, thus enabling access to CS lesions.

METHODS

A microcatheter is initially advanced into the IPS orifice, and a microguidewire is passed into the occluded IPS. Looping is easily achieved through the resistance met. With greater support of the guiding catheter, the microguidewire (still looped) is then advanced into the CS. When nearing the CS, the microcatheter is further reinforced, and it is navigated along the microguidewire into the CS.

RESULTS

This technique was applied in 10 instances of CS-dAVF with ipsilateral IPS occlusion, enabling ipsilateral access to the CS. In eight cases (80%), microdevice advancement was successful, culminating in effective transvenous coil embolization. Clinical and radiologic outcomes in all patients were excellent, with no delayed post-procedural cranial palsies.

CONCLUSION

This microguidewire looping technique enables safe and effective entry into the CS during transvenous coil embolization of CS-dAVFs with ipsilateral IPS occlusion.

Dural Arteriovenous Fistulae: Imaging and Management

Intracranial dural arteriovenous fistulae (DAVF) are pathologic arteriovenous shunts between meningeal arteries and dural venous sinuses or veins. They account for approximately 10% to 15% of all intracranial vascular malformations and are most common in middle-aged patients. DAVF are the most common vascular cause of pulsatile tinnitus. Digital subtraction angiography remains the gold standard for diagnosing these lesions. The pattern of venous drainage determines the type of DAVF and their risk for hemorrhage. Endovascular treatment has become a first-line option for their management. This article describes the natural history, clinical presentation, classification, imaging features, and management options of intracranial DAVF.

Diagnosis and management of intracranial dural arteriovenous fistulas

Dural arteriovenous fistula (DAVF) is a rare type of acquired intracranial vascular malformation. Recent progress in neuroimaging technology, such as advanced MRI and CT, provides non-invasive methods to accurately diagnose DAVF, including evaluation of the hemodynamics of the drainage veins. The clinical manifestations of DAVFs vary widely and depend on the location and venous drainage pattern of arteriovenous shunting. Patients with high grade DAVFs having cortical venous reflux should receive aggressive treatment to prevent the occurrence of intracranial hemorrhage and other neurological deficits related to venous congestion. Intra-arterial or intravenous endovascular embolization remains the primary therapy for high grade DAVF, while open surgery and stereotactic radiosurgery can serve as alternative treatment options. Early and accurate diagnosis with appropriate treatment is the goal for clinical management of DAVFs to reduce symptoms and prevent the development of venous congestion and stroke.

Endovascular Treatment of Cavernous Sinus Dural Arteriovenous Fistula With Ipsilateral Inferior Petrosal Sinus Occlusion

BACKGROUND:

Although a transvenous route via the ipsilateral inferior petrosal sinus (IPS) is preferred in treating cavernous sinus dural arteriovenous fistula (CSdAVF), this option may be limited if an occluded ipsilateral IPS undermines microcatheter delivery to the cavernous sinus.

OBJECTIVE:

To describe our experience with endovascular treatment of CSdAVF complicated by ipsilateral IPS occlusion.

METHODS:

From January 2003 through September 2014, a total of 49 CSdAVFs with ipsilateral IPS occlusion were identified in 49 patients, who then underwent endovascular treatment. Clinical and radiologic data were retrospectively reviewed.

RESULTS:

Either transvenous (n = 38) or transarterial (n = 11) access was initially elected, the latter reserved for single-hole or dominant arterial feeder fistulas. Access via occluded ipsilateral IPS was usually attempted (n = 34) by transvenous approach, with a 54.3% success rate. Anterior (n = 3) or posterior (n = 1) facial vein was alternatively used. Direct surgical exposure of ophthalmic vein (n = 3) or radiosurgery (n = 4) was performed for access failure or unsuccessful occlusion by other means. In 46 fistulas (93.9%), complete occlusion was achieved, with no procedure-related morbidity or mortality. Postprocedural symptom improvement was noted in all but 2 patients, who separately experienced paradoxical worsening of cranial nerve palsy and access failure.

CONCLUSION:

In patients with CSdAVF and ipsilateral IPS occlusion, various treatment strategies may be applied (given angioanatomic suitability), resulting in excellent procedural and short-term follow-up results. Reopening of an occluded IPS is reasonable as an initial access attempt.