Safety of spinal angiography: complication rate analysis in 302 diagnostic angiograms

OBJECTIVE

Spinal digital subtraction angiography (SpDSA) continues to be the imaging gold standard for the evaluation of spinal cord vascular disorders. The safety of this procedure has a poor historical reputation and there are few current reports on complication rates. We hypothesized that modern SpDSA can be performed with an acceptably low risk of iatrogenic complications.

METHODS

In this retrospective series, we reviewed 302 consecutive spinal angiograms performed during a 10-year period at our institution for the frequency of intraprocedural and postprocedural neurologic, non-neurologic, and local complications. Indications for SpDSA, prior noninvasive imaging findings, and angiographic diagnoses for each case were assessed to evaluate the diagnostic contribution of the procedure.

RESULTS

There were no intraprocedural or postprocedural neurologic complications in the studied cohort. Systemic complications occurred in 2 cases (0.7%), in the form of back spasms in one patient and pulmonary edema in the other. Both recovered promptly and were discharged at baseline status. Access-site complications included 3 groin hematomas (1.0%), all managed conservatively. MRI findings showed 51% sensitivity and 83% specificity for spinal vascular malformations. A total of 31% of patients with the preangiographic diagnosis of transverse myelitis were found to have a vascular malformation.

CONCLUSION

SpDSA carries very low risks of neurologic and systemic complications, while offering a gold-standard level of diagnostic confidence for the evaluation of the normal and pathologic vasculature of the spinal cord.

Endovascular management of neurovascular arterial injuries in the face and neck

The diagnosis and treatment of traumatic vascular injuries continues to improve as new tools and techniques are developed. In addition to locoregional hemorrhagic complications, injuries to blood vessels in the neck and face can result in ischemic injuries to the brain and cervical spinal cord. Surgical access to these lesions may be difficult, and endovascular techniques, including stenting and embolization, now serve as definitive treatments in many instances. This article reviews the endovascular management of patients with arterial injuries in the neck and face.

A single center comparison of coiling versus stent assisted coiling in 90 consecutive paraophthalmic region aneurysms

INTRODUCTION

Aneurysm recurrence is a principle limitation of endovascular coiling procedures, with recurrence rates reported of >30%. The adjunct use of self-expandable stents has revolutionized the treatment of intracranial aneurysms, especially for complex morphologies, wide necks or unfavorable dome to neck ratios. However, further investigation into the durability and outcomes of stent assisted coiling procedures is required.

METHODS

The records of a prospective single center aneurysm database were retrospectively reviewed, and 90 consecutive patients with paraophthalmic aneurysms who underwent coil embolization were identified, 30 of which included stent placement. Patient demographics, aneurysm characteristics, coil packing density, angiographic results (initial and follow-up) and complications were analyzed.

RESULTS

Complete aneurysm occlusion was obtained on initial angiography in 13/30 (43.3%) stented and 19/60 (31.7%) non-stented patients. At ≤24 months (mean follow-up 12.8±6.2 months for stented and 12.8±6.6 months for non-stented group), aneurysm recurrence occurred in 3/26 (11.5%) stented and 14/39 (35.9%) non-stented patients (p<0.05). At the longest follow-up (mean 14.5±12.5 months for stented and 37.6±35.3 months for non-stented), aneurysm recurrence occurred in 4/26 (15.4%) stented and 17/41 (41.5%) non-stented patients (p<0.03). There was no statistically significant correlation between recurrence and aneurysm size or coiling packing.

CONCLUSIONS

Following endovascular coil embolization of paraophthalmic region aneurysms, recurrence rates at 2 years were significantly lower in patients who had stent assisted coiling (11.5%) compared with patients who had coiling procedures without the use of a stent (35.9%). Aneurysm size and coiling packing density did not significantly affect recurrence in our study population.

Intravascular ultrasound of the transverse sinus in two patients with pseudotumor cerebri: technical note

BACKGROUND

The etiology of transverse sinus stenosis in patients with pseudotumor cerebri syndrome (PTCS) is unknown. The imaging findings of transverse sinus stenosis in two patients with PTCS using intravascular ultrasound (IVUS) before and after endovascular therapy with stent placement are reported.

MATERIAL AND METHODS

Retrospective, two patient, technical note.

RESULTS

In both cases IVUS demonstrated focal intraluminal filling defects within the transverse sinuses, resulting in a narrowing of the sinus. In the first case, IVUS demonstrated cannulation of a narrow channel within the transverse sinus that initially precluded advancement of the stent. In the second case, IVUS demonstrated a significant narrowing when the pressure gradient was borderline and the area of stenosis was not obvious at angiography.

CONCLUSION

Besides distinguishing a potential extrinsic compression phenomenon from an intrinsic abnormality as the cause of the transverse sinus stenosis, IVUS also shows great promise as a tool helping to plan the interventional procedure and achieve optimal stent positioning in patients with PTCS.

Assessment of EmboGel--a selectively dissolvable radiopaque hydrogel for embolic applications

PURPOSE

To evaluate the embolic properties of an alginate-based embolic biomaterial (EmboGel) and its solvent (EmboClear) in treatment of aneurysms.

MATERIALS AND METHODS

EmboGel is a mixture of iohexol and alginate that polymerizes into a hydrocoil when delivered through a coaxial catheter with a distal mixing tip, exposing alginate to a calcium chloride solution. In contrast to previously reported embolic agents, EmboGel can be selectively dissolved by EmboClear, a mixture of the enzyme alginate lyase and ethylenediaminetetraacetic acid (EDTA). The embolic and contrast properties of EmboGel were assessed in in vitro models of saccular aneurysm and an aortic aneurysm endoleak. The dissolvability of EmboGel with EmboClear was assessed further after endovascular delivery in the New Zealand white rabbit in the native aortoiliofemoral territory, a created saccular aneurysm, and the native carotid arteries.

RESULTS

EmboGel effectively filled aneurysm cavities in the case of stent excluded saccular and fusiform aneurysms. EmboGel was readily dissolved by EmboClear in vitro and after in vivo embolization. When the distal abdominal aorta and pelvic arteries were occluded with EmboGel, within 1 minute of EmboClear infusion, patency of the aorta and most of the pelvic circulation was regained as noted by angiography. Embolization in the subclavian artery and numerous distal branches was rapidly dissolved by EmboClear. Finally, the carotid artery occluded with EmboGel regained patency after administration of EmboClear.

CONCLUSIONS

EmboGel is a dissolvable alginate-based biomaterial that can be used for numerous embolic applications. EmboGel can be selectively dissolved with EmboClear, a solution of alginate lyase and EDTA.

Endovascular management of vein of Galen aneurysmal malformations. Influence of the normal venous drainage on the choice of a treatment strategy

INTRODUCTION

Vein of Galen arteriovenous malformations (VGAM) are rare intracranial vascular lesions mostly involving young children. Endovascular therapy is the current standard of care. Albeit interventional techniques have greatly reduced the once dismal vital and functional prognoses previously associated with these lesions, the treatment of VGAMs remains a complex therapeutic challenge.

DISCUSSIONS

This article reviews the available endovascular options for VGAM therapy, emphasizing three points that we have identified as critical in our practice for the establishment of a treatment strategy: (1) the importance of the deep cerebral venous anatomy, in particular the existence of normal drainage through the Galenic system in spite of the VGAM; (2) the concept of treatment staging, for arterial as well as for venous interventions; and (3) the definition of a therapeutic goal that can be attained at a reasonable cost in terms of complication risks and functional outcome.

Thrombosis and subsequent recanalization of a ruptured intracranial aneurysm in 2 children, demonstrating the value of repeating catheter angiography after an initial negative study

The cases of 2 children with true aneurysmal subarachnoid hemorrhages (SAHs) and initial false-negative angiograms are reported. In both cases, the initial angiogram was of adequate technical quality and included the projections on which aneurysms were later documented. There was no significant vasospasm at the time of initial angiography; therefore, transient aneurysm sac thrombosis was the most likely explanation for the initial false-negative studies. It is particularly interesting to note that 1 of the 2 patients had a pattern of hemorrhage compatible with the most limited definition of a perimesencephalic SAH, that is, a small prepontine cistern hemorrhage. If a second angiogram had been deemed unnecessary based on that criterion alone, a ruptured basilar tip aneurysm would have escaped detection and treatment.

Recovery from spatial neglect and hemiplegia in a child despite a large anterior circulation stroke and Wallerian degeneration

Prognosis after stroke in children is difficult given the paucity of literature regarding motor and cognitive recovery. Spatial neglect has been described in children after stroke, yet little evidence exists to guide clinicians and parents regarding its resolution. Wallerian degeneration on magnetic resonance imaging (MRI) suggests poor recovery in neonates and adults. We report near complete resolution of spatial neglect in 4 weeks and significant improvement in hemiplegia in a 9-year-old boy with a right anterior cerebral artery and middle cerebral artery infarction, despite Wallerian degeneration apparent on diffusion-weighted imaging. Serial assessment of neglect documenting the rapid course of recovery is the unique feature of this case and may help serve as a guide to pediatricians and neurologists in assessment of young patients and counseling of parents. The lack of published outcome data suggests a need for larger studies about the recovery of spatial neglect and other cognitive symptoms following pediatric stroke.

Intraoperative indocyanine green angiography for obliteration of a spinal dural arteriovenous fistula

Spinal dural arteriovenous fistulas (DAVFs) are the most common type of spinal arteriovenous malformation and are an important, underdiagnosed cause of progressive myelopathy and morbidity in patients with spine disorders. Successful microsurgical management of these lesions is dependent on the surgeon's ability to identify vessels of the fistula and to confirm its successful obliteration postintervention. Indocyanine green (ICG) fluorescent angiography is an emerging tool for delineating intraoperative vascular anatomy, and it has significant potential utility in the treatment of vascular disease in the spine. The authors present the case of a 76-year-old man with progressive and debilitating bilateral lower-extremity weakness and numbness on exertion, in whom a left T-8 spinal DAVF was diagnosed based on results of conventional spinal angiography. Unfavorable anatomy based on angiographic findings precluded endovascular embolization of the fistula, and the patient subsequently underwent T7-9 bilateral laminectomies for microsurgical clip occlusion. Intraoperative ICG fluorescent angiography was used before clip placement to identify the arterialized veins of the fistula, and after clip placement to confirm obliteration of the fistulous connection and restoration of normal blood flow. Intraoperative ICG angiography serves an important role in the microsurgical treatment of DAVF. It can be used to map the anatomy of the fistula in real time during surgery and to verify fistula obliteration rapidly after clip placement. This report adds to the growing body of literature demonstrating the importance of ICG angiography in vascular neurosurgery of the spine.

Arteria lusoria: developmental anatomy, clinical, radiological and surgical aspects

The left aortic arch with an aberrant right subclavian artery, or arteria lusoria, is the most common aortic arch anomaly, occuring in 0.5-2.5% of individuals. Four vessels arise sequentially from the aortic arch: the right common carotid artery, the left common carotid artery, the left subclavian artery and the aberrant right subclavian artery, which crosses upwards and to the right in the posterior mediastinum. It results from a disruption in the complex remodelling of the paired branchial arches, typically of the right dorsal aorta distal to the sixth cervical intersegmental artery. The diagnosis and differentiation of arch anomalies is based on findings at chest radiography in association with those at esophagography. It is usually asymptomatic. When symptomatic, it produces dysphagia lusoria or dyspnea and chronic coughing. Treatment is indicated for symptomatic relief of dysphagia lusoria and for prevention of complications due to aneurysmal dilatation.

Developmental anatomy, angiography, and clinical implications of orbital arterial variations involving the stapedial artery

Classical anatomists have provided detailed description of the arterial collateral pathways found in the head and neck. The small branches building this intricate network are difficult to access. The arterial map inherited from the anatomists has been put to the test with detailed high-resolution vascular imaging. Superselective angiography has helped rediscover the complexity of the craniocervical arterial network. The concept of dangerous collaterals or dangerous anastomoses was born with the advent of endovascular therapy. Although dangerous anastomoses of the skull base are described in the literature, variations and collateral pathways have been overlooked or misunderstood. This article reviews normal orbital arterial vascularization and its principal variations.

Regression of cerebral calcifications after endovascular treatment in a case of vein of Galen arteriovenous malformation

The authors present the case of an infant harboring a vein of Galen arteriovenous malformation with conspicuous cerebral calcifications that progressively regressed after staged endovascular obliteration of the lesion. The role of venous hypertension and hydrocephalus secondary to the arteriovenous shunt are discussed to explain the formation and regression of the cerebral calcifications.

Middle cerebral artery branch occlusion mimicking a saccular aneurysm on 3D digital subtraction angiography

The angiographic appearance of an intracranial arterial occlusion is typically distinct from that of a saccular aneurysm, with only a few reported cases of occlusion simulating aneurysm. At the same time, a small percentage of symptomatic intracranial aneurysms present with a stroke. Accurate diagnosis of these conditions is crucial, as their treatment differs. The authors report on a case of middle cerebral artery occlusion that mimicked the appearance of an aneurysm on angiography in the setting of acute stroke. The true diagnosis was not elucidated until repeated angiography 6 months later revealed recanalization of the previously occluded middle cerebral artery branch. This angiographic pitfall is important to consider when acute stroke is suspected as the mode of presentation of a saccular aneurysm.