Comprehensive Endovascular and Open Surgical Management of Cerebral Arteriovenous Malformations

Summary

Surgery is the gold standard for accessible arteriovenious malformations (AVMs), and pre-operative embolization can simplify this procedure. We describe our approach for staged endovascular embolization and open resection of AVMs, and provide a representative clinical example highlighting the advantages of a comprehensively trained neurovascular surgeon leading a multi-disciplinary clinical team.

Abstract

Arteriovenious malformations (AVMs) are associated with significant morbidity and mortality, and have a rupture risk of ~3% per year. Treatment of AVMs must be tailored specifically to the lesion, with surgical resection being the gold standard for small, accessible lesions. Pre-operative embolization of AVMs can reduce nidal blood flow and remove high-risk AVM features such as intranidal or venous aneurysms, thereby simplifying a challenging neurosurgical procedure. Herein, we describe our approach for the staged endovascular embolization and open resection of AVMs, and highlight the advantages of having a comprehensively trained neurovascular surgeon leading a multi-disciplinary clinical team. This includes planning the craniotomy and resection to immediately follow the final embolization stage, thereby using a single session of anesthesia for aggressive embolization, and rapid resection. Finally, we provide a representative case of a 22-year-old female with an unruptured right frontal AVM diagnosed during a seizure workup, who was successfully treated via staged embolizations followed by open surgical resection.

Introduction

Cerebral arteriovenous malformations (AVMs), abnormal connections between arteries and veins without intervening normal capillary beds, present unique neurosurgical challenges. Classified based on size, presence of deep draining veins, and involvement of eloquent cortex,¹ the risk of hemorrhage for previously unruptured AVMs ranges from 0.9 to 8% per year,² with an annual average rupture risk of ~3%.³ Hemorrhages from AVMs are associated with a nearly 10% mortality rate and significant morbidity, with up to 34% of patients having moderate to severe disabilities.⁴ Previously....

Protocol

All procedures described below are performed as standard of care for patients with cerebral AVMs, after obtaining informed consent as per institutional guidelines.

1. Initial patient evaluation and imaging

NOTE: Patients with unruptured AVMs often present after the malformation is discovered on imaging for headache or seizure workup. Patients with ruptured AVMs often present with acute onset of headache, nausea, vomiting, weakness, numbness, and/or vision changes.

1. Obtain a thorough history by interviewing the patient and/or family (to determine previous rupture status, family history) and perform a de....

Results

A 22-year-old previously healthy female presented with new onset seizures. Non-contrast head CT was negative for acute hemorrhage, but revealed an incompletely characterized right frontal lesion. MRI demonstrated an approximately 2.9 x 2.4 cm Spetzler-Martin Grade 3 AVM within the right superior frontal gyrus (Figure 1), with large draining cortical veins going to the superior sagittal sinus, and an arterial supply via large branches off the right middle cerebral artery. .......

Discussion

Here we demonstrate a comprehensive approach to cerebral AVMs via combined endovascular and open surgical management. Catheter angiography is the gold standard for imaging AVMs, and is critical to surgical evaluation and planning. Pre-operative embolizations can simplify surgical resection, but requires communication between the surgical and interventional teams to develop an optimal strategic approach. For example, the AVM arterial feeders most easily embolized may also be the most surgically accessible. If, however, th.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
ChloraPrep Sterilization Solution	BD, Franklin Lakes, NJ	260815	For skin sterilization
Lidocaine Hcl 1%	ACE Surgical Supply, Inc, Brockton, MA	001-1421	For local anesthetic
Micropuncture Groin Access Kit	Cook Medical, Bloomington, IN	G56202	Used for femoral artery access
0.035 Guidewire	Terumo Medical, Somerset, NJ	GR3506	Used in conjunction with diagnostic catheters for cerebral angiography
Cerebral Angiography Diagnostic Catheters	Terumo Medical, Somerset, NJ	CG416	Used in conjunction with guidewire for cerebral angiography
Omnipaque Contrast Agent	GE Healthcare, Chicago, IL	Q9965	Contrast agent for cerebral vessel imaging
Microcatheter and Microwire	Covidian, Plymouth, MN	105-5091-150, 103-0608	Used for distal arterial catheterization
Onyx Liquid Embolic	Covidian, Plymouth, MN	105-7100-060	Used for AVM embolization
Angio-Seal Vascular Closure Device	St. Jude Medical, St Paul, MN	610130	Used for femoral artery closure following angiography/intra-arterial embolization
Midas Rex High Power Drill System	Medtronic, Minneapolis, MN	PM700	Used for craniotomy
Matchstick Drill Bit	Medtronic, Minneapolis, MN	10MH30-MN	Used to create burr hole for craniotomy
Tapered Drill Bit	Medtronic, Minneapolis, MN	F1/8TA15	Used to complete craniotomy
#11 and 15 Blade Surgical Scalpels	BD Bard-Parker, Franklin Lakes, NJ	372615	Used for groin incision for angiography and dural opening for external ventricular drain placement or AVM resection
Metzenbaum Dissecting Scissors	Stoelting Co, Wood Dale, IL	52134-01P	Used for dural opening
Bone Elevator	Stoelting Co, Wood Dale, IL	52169	Used for separating dura from the inner skull
Gerald Forceps	Stoelting Co, Wood Dale, IL	52106-52	Used for dural opening and manipulation
Microsurgical Instruments	Accurate Surgical & Scientific Instruments Corporation, Westbury, NY	ASSI.BML1	Used for AVM microsurgical resection
Bipolar Forceps	Accurate Surgical & Scientific Instruments Corporation, Westbury, NY	ASSI.BPNS20423FP	Used for AVM microsurgical resection
Electrosurgery Generator	Bovie Medical Products, Clearwater, FL	IDS-200	Used for electrosurgical cutting/coagulation
Small Aneurysm Clips	Codman Neuro, Raynham, MA	20-1801	Used for occlusion of arterial AVM feeders not amenable to coagulation
Brain Retractors	Medicon, Tuttlingen, Germany	22.00.06	For brain retraction for deep AVM dissection/resection
Variable Action Suction tip	Millennium Surgical, Narberth, PA	6-8607	For suction with AVM dissection/resection
Fibrillar Absorbable Hemostatic Agent	Ethicon, Somerville, NJ	63713-0019-61	For hemostatis within surgical cavity
4-0 Suture	Ethicon, Somerville, NJ	C554D	For dural closure
2-0 Absorbable Suture	Ethicon, Somerville, NJ	J286G	For deep tissue closure
3-0 Nylon Suture	Ethicon, Somerville, NJ	ET-663G	For skin closure
Surgical Staples	Medline, Mundelein, IL	STAPLER35RB	For skin closure
Bone Plating System	Biomet, Warsaw, IN	15-7378-12	For bone flap securement
Operating Microscope	Leica Microsystems, Buffalo Grove, IL	M720 OH5	Used for AVM microsurgical resection
BrainLab Neuronavigation Imaging System	Brainlab, Inc, Chicago, IL	Brainlab Curve	Used for AVM microsurgical resection
Lumbar External Drainage System	Codman Neuro, Raynham, MA	K964923	Used for placement of lumbar drain for CSF drainage
External Ventricular Drainage Catheter	Medtronic, Minneapolis, MN		Used for placement of ventricular catheter for CSF drainage
Disposable Raney Scalp Clips	A&E Medical Corporation, Farmingdale, NJ	070-001	Used for scalp hemostasis