Delayed caroticocavernous fistula after stent-assisted coil embolization of intracavernous carotid aneurysm: should we manage conservatively?

Likelihood of spontaneous closure of cavernous sinus dural arteriovenous fistulas based on clinical and radiological findings

BACKGROUND

Cavernous sinus dural arteriovenous fistula (CSDAVF) is a rare condition that radiologists would encounter in their careers. We aim to describe the clinical and radiological characteristics of this condition, and to provide a management workflow.

METHODS

In our retrospective study, we studied 27 patients with CSDAVF from January 2007 to August 2020. Patients with direct cavernous sinus AVFs and patients with incomplete date were excluded. Clinical and radiological data were collected and analyzed.

RESULTS

Fourteen patients were conservatively treated with spontaneous resolution while 13 patients had endovascular intervention performed. In the intervention group, seven patients had intra-cranial reflux seen on radiological imaging and six patients had clinical deterioration, hence requiring intervention. Clinically, among our patients, 21 had proptosis, 20 had conjunctiva hyperaemia, 18 had extraocular movement limitation, 13 had raised intraocular pressure, 11 had chemosis, ten had ocular pain, nine had ocular bruit, eight had headache and six had worsening visual acuity. Radiologically, a concurrence was seen between superior ophthalmic vein thrombosis and spontaneous resolution of the CSDAVF, as compared to those who underwent intervention. A paradoxical increase of ocular symptoms was seen despite a decrease of flow or stagnation of contrast in radiological imaging of CSDAVF.

CONCLUSIONS

In our study, 52% of CSDAVF closed spontaneously. As deterioration of ocular symptoms in patients with CSDAVF might also reflect spontaneous progressive occlusion, it warrants dynamic vascular imaging to check the status of venous outflow. Patients with CSDAVF with corticovenous reflux or deterioration of visual acuity need more urgent (endovascular) treatment.

The new generation double layered flow diverters for endovascular treatment of intracranial aneurysms: current status of ongoing clinical uses

INTRODUCTION

The treatment of intracranial aneurysms has significantly evolved over the last decade with the advancement in endovascular techniques and devices. Flow diverters are the latest in the armamentarium for vascular reconstruction, aneurysm exclusion, and preservation of branch vessels. The possibility of treating various types of intracranial aneurysms, including those previously considered untreatable, has represented a new paradigm in the neurovascular era.

AREAS COVERED

This paper describes in detail the current status in the use of new generation double-layered Flow Redirection Endoluminal Device (FRED; MicroVention Terumo, Tustin, California). For this report, we reviewed the published literature for properties of the currently available FRED devices regarding safety, efficacy, and potential risks and complications associated with their use.

EXPERT OPINION

FRED and FRED Jr are the new flow diverter devices for which the existing data suggest that they are safe and efficient in addressing the treatment issues with giant, wide-necked saccular and fusiform aneurysms and those with perforators and branch vessels at high risk of occlusion with surgical clipping. Evidence is mounting on their long-term durability which increases the confidence of both the endovascular surgeon in prescribing and the patient side in accepting these FDs as treatment option for intracranial aneurysms.

Carotid cavernous fistula after Pipeline placement: a single-center experience and review of the literature

Objective

Carotid cavernous fistula (CCF) development after Pipeline Embolization Device (PED) treatment of cavernous carotid aneurysms (CCA) can be a challenging pathology to treat for the neurointerventionalist.

Methods

A database of all patients whose aneurysms were treated with the PED since its approval by the Food and Drug Administration in 2011 was retrospectively reviewed. Demographic information, aneurysm characteristics, treatment technique, antiplatelet regimen, and follow-up data were collected. A literature review of all papers that describe PED treatment of CCA was then completed.

Results

A total of 44 patients with 45 CCAs were identified (38 women, 6 men). The mean age was 59.9±9.0 years. The mean maximal aneurysm diameter was 15.9±6.9 mm (mean neck 7.1±3.6 mm). A single PED was deployed in 32 patients, with two PEDs deployed in 10 patients and three PEDs in 3 patients. Adjunctive coiling was performed in 3 patients. Mean follow-up duration based on final imaging (MR angiography or digital subtraction angiography) was 14.1±12.2 months. Five patients (11.4%) developed CCFs in the post-procedural period after PED treatment, all within 2 weeks of device placement. These CCFs were treated with a balloon test occlusion followed by parent artery sacrifice. Our literature review yielded only three reports of CCFs after PED placement, with the largest series having a CCF rate of 2.3%.

Conclusions

CCF formation is a known risk of PED treatment of CCA. Although transvenous embolization can be used for treating CCFs, parent artery sacrifice remains a viable option on the basis of these data. Studies support the view that adjunctive coiling may have a protective effect against post-PED CCF formation. None of the coiled aneurysms in our database or in the literature have ruptured. Follow-up data will lead to a better understanding of the safety profile of the PED for CCA.

Flow Diversion for Intracranial Aneurysm Management: A New Standard of Care

Endovascular treatment of intracranial aneurysms with complex morphologies such as giant, wide-necked, or fusiform aneurysms is challenging. Stent-assisted coiling and balloon-assisted coiling are alternative techniques to treat such complex aneurysms, but studies have shown less-than-expected efficacy, as suggested by their high rate of recanalization. The management of complex aneurysms via microsurgery or conventional neuroendovascular strategies has traditionally been poor. However, over the last few years, flow-diverting stents (FDS) have revolutionized the treatment of such aneurysms. FDS are implanted within the parent artery rather than the aneurysm sac. By modifying intra-aneurysmal and parent-vessel flow dynamics at the aneurysm/parent vessel interface, FDS trigger a cascade of gradual intra-aneurysmal thrombosis. As endothelialization of the FDS is complete, the parent vessel reconstructs while preserving the patency of normal perforators and side branch vessels. As with any intervention, the practice and application of flow-diversion technology is inherent, with risks that include vessel rupture or perforation, in-stent thrombosis, perforator occlusion, procedural and delayed hemorrhages, and perianeurysmal edema. Herein, we review the devices, their mechanisms of actions, clinical applications, complications, and ongoing studies.

Transvenous approach for the treatment of direct carotid cavernous fistula following Pipeline embolization of cavernous carotid aneurysm: a report of two cases and review of the literature

Flow diverters are increasingly used for the endovascular treatment of cerebral aneurysms. A rare complication from flow diversion is delayed aneurysm rupture, which can lead to carotid-cavernous fistula (CCF) in the setting of cavernous carotid aneurysms (CCAs). Direct CCFs pose unique management challenges, given the lack of transarterial access to the fistula. We present two cases of direct CCFs following treatment of CCAs with the Pipeline embolization device (PED). Case 1 was a middle-aged patient with a symptomatic 10 mm wide-necked left CCA. Six weeks after PED treatment the patient developed diplopia secondary to direct CCF. Case 2 was a middle-aged patient with a symptomatic 17 mm left CCA treated with PED. One-month follow-up angiography demonstrated a direct CCF. Both patients underwent successful coil embolization of the CCF through a transvenous approach. Direct CCF formation following PED deployment for CCA is a rare complication. Parent vessel sacrifice may be avoided with transvenous occlusion of the fistula.

Flow diverters for intracranial aneurysms

Flow diverters (pipeline embolization device, Silk flow diverter, and Surpass flow diverter) have been developed to treat intracranial aneurysms. These endovascular devices are placed within the parent artery rather than the aneurysm sac. They take advantage of altering hemodynamics at the aneurysm/parent vessel interface, resulting in gradual thrombosis of the aneurysm occurring over time. Subsequent inflammatory response, healing, and endothelial growth shrink the aneurysm and reconstruct the parent artery lumen while preserving perforators and side branches in most cases. Flow diverters have already allowed treatment of previously untreatable wide neck and giant aneurysms. There are risks with flow diverters including in-stent thrombosis, perianeurysmal edema, distant and delayed hemorrhages, and perforator occlusions. Comparative efficacy and safety against other therapies are being studied in ongoing trials. Antiplatelet therapy is mandatory with flow diverters, which has highlighted the need for better evidence for monitoring and tailoring antiplatelet therapy. In this paper we review the devices, their uses, associated complications, evidence base, and ongoing studies.

Intracavernous internal carotid artery mycotic aneurysms: comprehensive review and evaluation of the role of endovascular treatment

Mycotic aneurysms may arise in the setting of many local or systemic infections. Those of the intracranial circulation are especially worrisome due to their potential to compress vital neural structures and their propensity for rupture with consequent hemorrhage. Mycotic aneurysms of the intracavernous internal carotid artery (ICA) represent an exceedingly rare clinical entity, described in less than fifty published cases. Typically presenting as a cavernous sinus syndrome with signs and symptoms of the underlying infection, they are often missed initially, with diagnosis and treatment commencing for the triggering infection or confused with cavernous sinus thrombophlebitis, which may be additionally coexistent, confounding timely diagnosis of the aneurysmal disease. Compared to non-mycotic aneurysms of the intracavernous ICA, which typically have a benign course, the infectious etiology of the mycotic variety increases their tendency to rupture, precludes surgical clipping as a viable treatment option, and requires institution of prolonged antibiotic therapy prior to definitive intervention. Their critical location, friability, and propensity to occur bilaterally result in an unpredictable risk of rapid neurological decline and death, making the timing and specific nature of treatment a unique dilemma facing the treating physician. This review seeks to discuss the natural history of and management strategies for mycotic aneurysms of the intracavernous ICA with special emphasis on the role, safety, and efficacy of endovascular therapies.

Pipeline for uncoilable or failed aneurysms: results from a multicenter clinical trial

PURPOSE

To evaluate the safety and effectiveness of the Pipeline Embolization Device (PED; ev3/Covidien, Irvine, Calif) in the treatment of complex intracranial aneurysms.

MATERIALS AND METHODS

The Pipeline for Uncoilable or Failed Aneurysms is a multicenter, prospective, interventional, single-arm trial of PED for the treatment of uncoilable or failed aneurysms of the internal carotid artery. Institutional review board approval of the HIPAA-compliant study protocol was obtained from each center. After providing informed consent, 108 patients with recently unruptured large and giant wide-necked aneurysms were enrolled in the study. The primary effectiveness endpoint was angiographic evaluation that demonstrated complete aneurysm occlusion and absence of major stenosis at 180 days. The primary safety endpoint was occurrence of major ipsilateral stroke or neurologic death at 180 days.

RESULTS

PED placement was technically successful in 107 of 108 patients (99.1%). Mean aneurysm size was 18.2 mm; 22 aneurysms (20.4%) were giant (>25 mm). Of the 106 aneurysms, 78 met the study's primary effectiveness endpoint (73.6%; 95% posterior probability interval: 64.4%-81.0%). Six of the 107 patients in the safety cohort experienced a major ipsilateral stroke or neurologic death (5.6%; 95% posterior probability interval: 2.6%-11.7%).

CONCLUSION

PED offers a reasonably safe and effective treatment of large or giant intracranial internal carotid artery aneurysms, demonstrated by high rates of complete aneurysm occlusion and low rates of adverse neurologic events; even in aneurysms failing previous alternative treatments.