Spontaneous occlusion of a spinal arteriovenous malformation: is treatment always necessary?

Spontaneous thrombosis of high flow pediatric arteriovenous fistulae: Case series of two patients and a comprehensive literature review

Pediatric pial arteriovenous shunts in the brain and spine are challenging to understand because of low incidence, variable presentation, and associations with genetic syndromes. What is known about their natural history comes from reviews of small series. To better understand the natural history and role for intervention, two cases are presented followed by a review of the literature. In the first case, an infant with a prior history of intracranial hemorrhage from a ruptured pial fistula returns for elective embolization for a second pial fistula which was found to be spontaneously thrombosed 2 weeks later. In the second case, a 5-year-old with a vertebro-vertebral fistula, identified on work up for a heart murmur and documented with diagnostic angiography, is brought for elective embolization 6 weeks later where spontaneous thrombosis is identified. In reviewing the literature on pediatric single-hole fistulae of the brain and spine, the authors offer some morphologic considerations for identifying which high-flow fistulae may undergo spontaneous thrombosis to decrease the potentially unnecessary risk associated with interventions in small children.

Two pediatric observations of spinal extradural arteriovenous fistulas presenting with epidural hemorrhages and cord compression

We report two cases of acute spinal cord compression in children with low-flow spinal epidural arteriovenous fistulas (SEAVFs) and discuss the clinical presentation and management of these vascular anomalies. While most low-flow SEAVFs without radiculomedullary drainage are benign lesions typically diagnosed incidentally, we suggest that asymptomatic lesions may warrant aggressive management in specific circumstances, including lesions diagnosed at an early age or in patients under anticoagulation therapy. Our observations also emphasize that patients with a "spontaneous" epidural hemorrhage should undergo dedicated preoperative or postoperative vascular imaging to identify a possible underlying vascular anomaly.

Spontaneous regression of extradural high-flow vascular malformation in spinal arteriovenous metameric syndrome (SAMS): A unique case report

Background

Spinal arteriovenous metameric syndrome (SAMS) is a rare nonhereditary genetic vascular disorder, involving multiple layers of tissues in the same metameric level. Spontaneous regression of SAMS has never been reported in the medical literature.

Case Description

A 42-year-old woman presented with intermittent low back pain for 6 months. Magnetic resonance imaging of the thoracolumbar spine incidentally found clusters of spinal vascular malformations involving spinal cord, vertebral bodies, epidural space, and paraspinal muscles. There was no sign of venous congestion. Magnetic resonance angiography and spinal angiography revealed intradural spinal cord arteriovenous malformation (SCAVM) at the level of T10-11 and extradural high-flow osseous arteriovenous fistula. Due to asymptomatic SAMS and a high risk of anterior spinal arterial compromise during treatment, conservative treatment was considered in our patient. Spinal angiography obtained 8 years after initial angiography demonstrated significant regression of extradural component of SAMS and stable intradural SCAVM.

Conclusion

We describe a unique case of SAMS with spontaneous regression of extradural component during a long-term observation period.

Spinal cord motor disorders

Spinal cord diseases are frequently devastating due to the precipitous and often permanently debilitating nature of the deficits. Spastic or flaccid paraparesis accompanied by dermatomal and myotomal signatures complementary to the incurred deficits facilitates localization of the insult within the cord. However, laboratory studies often employing disease-specific serology, neuroradiology, neurophysiology, and cerebrospinal fluid analysis aid in the etiologic diagnosis. While many spinal cord diseases are reversible and treatable, especially when recognized early, more than ever, neuroscientists are being called to investigate endogenous mechanisms of neural plasticity. This chapter is a review of the embryology, neuroanatomy, clinical localization, evaluation, and management of adult and childhood spinal cord motor disorders.

Spontaneous closure of an incidental high-flow paravertebral arteriovenous fistula caused by vertebral giant cell tumor curettage: illustrative case

BACKGROUND

Paravertebral arteriovenous fistula (AVF) after spinal surgery is rarely reported in the literature. Its natural course is largely unknown.

OBSERVATIONS

The authors report a 31-year-old woman with a high-flow AVF after T12 vertebral giant cell tumor curettage. Eight months after the initial surgery, revision en bloc surgery was planned. Preoperative computed tomography angiography was performed for vascularity assessment, which incidentally revealed a large paravertebral early-enhanced venous sac. High-flow AVF was confirmed through subsequent spinal angiography. Endovascular embolization was scheduled before the surgery to avoid massive blood loss. However, the AVF closed spontaneously 1 month after the spinal angiography. The plan was changed to preoperative embolization; subsequently, three-level en bloc spondylectomy was performed smoothly.

LESSONS

Iatrogenic AVF is possible, prompting investigation by vascular imaging when suspected. Embolization is a preferred treatment method when feasible. However, for iatrogenic etiology, the prothrombotic property of the contrast medium may induce the resolution. Multidisciplinary discussion can be very helpful before aggressive spinal surgery.

Towards precision nanomedicine for cerebrovascular diseases with emphasis on Cerebral Cavernous Malformation (CCM)

Introduction: Cerebrovascular diseases encompass various disorders of the brain vasculature, such as ischemic/hemorrhagic strokes, aneurysms, and vascular malformations, also affecting the central nervous system leading to a large variety of transient or permanent neurological disorders. They represent major causes of mortality and long-term disability worldwide, and some of them can be inherited, including Cerebral Cavernous Malformation (CCM), an autosomal dominant cerebrovascular disease linked to mutations in CCM1/KRIT1, CCM2, or CCM3/PDCD10 genes.Areas covered: Besides marked clinical and etiological heterogeneity, some commonalities are emerging among distinct cerebrovascular diseases, including key pathogenetic roles of oxidative stress and inflammation, which are increasingly recognized as major disease hallmarks and therapeutic targets. This review provides a comprehensive overview of the different clinical features and common pathogenetic determinants of cerebrovascular diseases, highlighting major challenges, including the pressing need for new diagnostic and therapeutic strategies, and focusing on emerging innovative features and promising benefits of nanomedicine strategies for early detection and targeted treatment of such diseases.Expert opinion: Specifically, we describe and discuss the multiple physico-chemical features and unique biological advantages of nanosystems, including nanodiagnostics, nanotherapeutics, and nanotheranostics, that may help improving diagnosis and treatment of cerebrovascular diseases and neurological comorbidities, with an emphasis on CCM disease.

Surgical management of combined intramedullary arteriovenous malformation and perimedullary arteriovenous fistula within the hybrid operating room after five years of performing focus fractionated radiotherapy: case report

Perimedullary arteriovenous fistula (AVF) shunts occur on the spinal cord surface and can be treated surgically or by endovascular embolization. In contrast, the nidus of an intramedullary arteriovenous malformation (AVM) is located in the spinal cord and is difficult to treat surgically or by endovascular techniques. The benefits of radiotherapy for treating intramedullary AVM have been published, but are anecdotal and consist largely of case reports. We present a case of combined cervical intramedullary AVM and perimedullary AVF which received surgical treatment within a hybrid operating room (OR) after 5 years of focus fractionated radiotherapy. A 37-year-old male presented with stepwise worsening myelopathy. Magnetic resonance imaging and spinal angiography revealed intramedullary AVM and perimedullary AVF at the C3 to C5 levels. In order to reduce nidus size and blood flow, we first performed focal fractionated radiotherapy. Five years later, the lesion volume was reduced. Following this, direct surgery was performed by an anterior approach using corpectomy in the hybrid OR. The spinal cord was monitored by motor-evoked potential throughout the surgery. Complete obliteration of the fistulous connection was confirmed by intraoperative indocyanine green video-angiography and intraoperative angiography, preserving the anterior spinal artery. We conclude that surgical treatment following focal fractionated radiotherapy may become one strategy for patients who are initially deemed ineligible for endovascular embolization and surgical treatment. Furthermore, the hybrid OR enables safe and precise treatment for spinal vascular disorders in the fields of endovascular treatment and neurosurgery.

Microsurgical management of glomus spinal arteriovenous malformations: pial resection technique: Clinical article

OBJECT

Intramedullary, or glomus, spinal arteriovenous malformations (AVMs) are rare vascular lesions amenable to resection with or without adjuvant embolization. The authors retrospectively reviewed the senior author's (R.F.S.'s) surgical series of intramedullary spinal AVMs to evaluate clinical and radiographic outcomes.

METHODS

Detailed chart and radiographic reviews were performed for all patients with intramedullary spinal AVMs who underwent surgical treatment between 1994 and 2011. Presenting and follow-up neurological examination results were obtained and graded using the modified Rankin Scale (mRS) and McCormick Scale. Surgical technique, outcomes, complications, and long-term angiographic studies were reviewed.

RESULTS

During the study period, 20 patients (10 males and 10 females) underwent resection of glomus spinal AVMs. The mean age at presentation was 30 ± 17 years (range 7-62 years). The location of the AVMs was as follows: cervical spine (n = 10), thoracic spine (n = 9), and cervicothoracic junction (n = 1). The most common presenting signs and symptoms included paresis or paralysis (65%), paresthesias (40%), and myelopathy (40%). Perioperative embolization was performed in the majority (60%) of patients. Pial AVM resection was performed in 17 cases (85%). Angiographically verified AVM obliteration was achieved in 15 patients (75%). At a mean follow-up duration of 45.4 ± 52.4 months (range 2-176 months), 14 patients (70%) remained functionally independent (mRS and McCormick Scale scores ≤ 2). One perioperative complication occurred, yielding a surgical morbidity rate of 5%. Three symptomatic spinal cord tetherings occurred at a mean of 5.7 years after AVM resection. No neurological decline was observed after endovascular and surgical interventions. No deaths occurred. Long-term angiographic follow-up data were available for 9 patients (40%) at a mean of 67.6 ± 60.3 months (range 5-176 months) following AVM resection. Durable AVM obliteration was documented in 5 (83%) of 6 patients.

CONCLUSIONS

Intramedullary AVMs may be safely resected with satisfactory clinical and angiographic results. The pial resection technique, which provides subtotal AVM nidus resection, effectively devascularized these lesions, as confirmed on postoperative angiography, without violating the spinal cord parenchyma, thereby potentially reducing iatrogenic injury.

Contrast agent induced obliteration of a spinal arteriovenous malformation

We present a patient undergoing spinal angiography and suspected of having an AVM. During the first injection of nonionic contrast, a nidal AVM supplied by the great anterior radiculomedullary artery at T9 left was found. The second injection at T9 left no longer showed the contrast filling of the AVM. Follow-up angiography showed persistent AVM obliteration with an intact arterial spinal axis. The patient's symptoms resolved. Interaction between nonionic contrast, blood, and vessel wall most likely induced the obliteration.