Microsurgical treatment and outcomes of spinal arteriovenous lesions: Learned from consecutive series of 105 lesions

Recurrence Rates Following Treatment of Spinal Vascular Malformations: A Systematic Review and Meta-Analysis

BACKGROUND

Spinal vascular malformations (SVMs), including arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs), are a varied group of vascular lesions that can be subclassified according to localization, vascular structure, and hemodynamics. Early intervention is necessary to halt progression of disease and minimize irreversible dysfunction. We sought to characterize initial treatment success and recurrence rates following interventional treatment of various types of SVMs.

METHODS

A systematic review and meta-analysis were performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. SVMs were categorized into 4 groups: dural AVFs, perimedullary AVFs, intramedullary AVMs, and extradural-intradural AVMs (e.g., epidural, paraspinal). Initial occlusion, recurrence, and complication rates were compared using random-effects analysis.

RESULTS

There were 112 manuscripts included, with a total of 5626 patients with SVM. For treatment, 2735 patients underwent endovascular embolization, 2854 underwent surgical resection, and 37 underwent stereotactic radiosurgery. The initial treatment success and overall recurrence rates following surgical resection of all SVMs were 89.5% (95% CI: 80.5%-98.5%) and 2.3% (95% CI: 0.9%-3.7%), respectively. Those rates following endovascular embolization were 55.9% (95% CI: 30.3%-81.5%) and 27.7% (95% CI: 11.2%-44.2%), respectively. Higher rates of initial treatment success and lower rates of recurrence with surgery were observed in all subtypes compared to embolization. Overall complication rates were higher after embolization for each of the SVM categories.

CONCLUSIONS

Surgical resection of SVMs provided higher rates of initial complete occlusion and lower rates of recurrence than endovascular techniques. Attaining technical success through obliteration must still be weighed against clinical impact and natural history of the specific vascular malformation.

Vascular Malformations of the Spinal Cord in Children

Vascular malformation of the spinal cord in children is a rare and complicated disease spectrum. We will start from the basic spinal cord vascular anatomy and the controversial classification of this kind of disease. Then, we will elaborate the clinical manifestations, diagnostic imaging and treatment of pediatric spinal vascular malformations based on the practical experience of our center and from literature.

Application of Indocyanine Green During Arteriovenous Malformation Surgery: Evidence, Techniques, and Practical Pearls

Indocyanine green (ICG) is a fluorescent molecule that enables visualization of hemodynamic flow through blood vessels. The first description of its application to the resection of arteriovenous malformations (AVMs) did not occur until 2007. Since then, industry leaders have rapidly integrated this optical technology into the intraoperative microscope, and the use of ICG videoangiography (VA) has since become routine in AVM surgery among some academic centers. A number of case series have been published since the introduction of ICG VA to AVM neurosurgery. These early reports with small sample sizes were largely qualitative, assigning to the technology “usefulness” and “benefit” scores as perceived by the operators. This lack of objectivity prompted the development of FLOW 800 software, a proprietary technology of Carl Zeiss Meditec AG (Oberkochen, Germany) that can quantify relative fluorescence intensity under the microscope to generate color maps and intensity curves for ad hoc and post hoc analyses, respectively. However, subsequent case series have done little to quantify the effect of ICG VA on outcomes. The available literature predominately concludes that ICG VA, although intuitive to deploy and interpret, is limited by its dependence on direct illumination and visualization. The subcortical components of AVMs represent a natural challenge to ICG-based flow analysis, and the scope of ICG VA has therefore been limited to AVMs with a high proportion of superficial angioarchitecture. As a result, digital subtraction angiography has remained the gold standard for confirming AVM obliteration. In this review, we provide an overview of the existing literature on ICG VA in AVM resection surgery. In addition, we describe our own experiences with ICG VA and AVMs and offer the senior author's surgical pearls for optimizing the marriage of fluorescence flow technology and AVM resection surgery.

Adult Spinal Arteriovenous Malformations: Natural History and a Multicenter Study of Short-Term Surgical Outcomes

OBJECTIVE

Spinal arteriovenous malformations (SAVMs) are a very rare and complex spinal cord pathology that require high clinical acumen to diagnose and treat. Management includes both nonoperative and operative paradigms. A review of the literature yields a paucity of data regarding the surgical outcomes of SAVMs, with the majority of data limited to single-center outcomes and/or small sample sizes. The purpose of this study was to use a multi-institutional international database to study the natural history of SAVMs.

METHODS

We used the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to select patients that underwent laminectomy for surgical excision of a SAVM between 2008 and 2017.

RESULTS

The data from 196 patients were studied (65.8% male, 34.2% female). A majority of cases were in the thoracic region (53.6%), followed by thoracolumbar (31.6%) and cervical (14.8%) regions. The mean age was 57.4 years and 52.5% patients were graded ASA class 3-5 before the operation. The mean operation time was 215 minutes, with a significantly lower operative time for thoracic arteriovenous malformations (195.6 minutes) when compared with cervical (266.6 minutes) and thoracolumbar (223.7 minutes). The mean length of hospital stay was 6.4 days. Patients had a 6.6% readmission rate and a 4.6% reoperation rate within 30 days.

CONCLUSIONS

This study presents the largest analysis of patients undergoing surgery for SAVMs and 30-day postoperative outcomes. Operative time differed based on SAVM location. The three most frequent complications (deep vein thrombosis, wound infection, and UTI) occurred at rates of 3.6% or less.