Original articleFollow-up of intracranial aneurysms treated with stent-assisted coiling: Comparison of contrast-enhanced MRA, time-of-flight MRA, and digital subtraction angiography
Introduction
Endovascular treatment has become a standard procedure for treating intracranial aneurysms [1], [2], [3]. Improved endovascular techniques such as balloon-assisted coiling, stent-assisted coiling, flow-diversion, and flow-disruption have made it possible to treat an increased number of aneurysms including those with complex and unfavorable anatomy [4], [5], [6], [7], [8]. However, the problem of aneurysm recanalization with the potential risk of future hemorrhage still remains a major concern after endovascular treatment [8]. Digital subtraction angiography (DSA) has been considered as the method of choice for the follow-up of an aneurysm after coiling; it is capable of clearly detecting any residual intra-aneurysmal flow and the patency of the parent vessel [9], [10], [11], [12], [13].
This invasive method has a low but inevitable risk of neurological and non-neurological (e.g., groin hematoma, allergy, nephropathy) complications [14]. To reduce these risks, several non-invasive cross-sectional imaging techniques like 3D-time-of-flight (TOF) magnetic resonance (MR) angiography (3D-TOF-MRA) and contrast-enhanced MR angiography (CE-MRA) were developed. These techniques are currently used in clinical routine to follow intracranial aneurysms after coil embolization [15], [16]. Because MR imaging of stents suffer from several physical limitations of which the most important remains the susceptibility artefacts [17], only few studies assessed the clinical value of MRA for non-invasive follow-up of aneurysms treated with stent-assisted coiling [18], [19], [20], [21]. Despite a direct comparison of different MRA methods, previous studies on MR stent imaging [18], [19], [20], [21] and equivalent studies on flow diverters [22] give a hint that CE-MRA might be superior to 3D-TOF-MRA, as the latter seems to be more prone to artefacts from the stent, thus resulting in difficulties to evaluate the parent artery and the aneurysm neck. Capitalizing on a direct comparison of 3D-TOF-MRA, CE-MRA and DSA, the present study aimed to make an in-depth analysis of current 3-Tesla MRA sequence accuracies for the evaluation of aneurysm occlusion and parent artery patency (as both of these are essential clinical questions) after stent-assisted coiling.
Section snippets
Study setting
Institutional review board approval was obtained and informed consent was waived according to the design of the study. The present study complies with the Standards for reporting of diagnostic accuracy (STARD) [23]. Consecutive patients treated for an intracranial aneurysm in our academic department were prospectively included in a database. For the purpose of the present study, patients imaged between March 2008 and June 2015 were included if they met the following criteria:
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they had an
Results
Thirty-three patients with 35 aneurysms treated by stent-assisted coiling fulfilled the inclusion criteria. This included 19 women and 14 men who had a median age of 56 [48–66] years, with 15 (42%) ruptured aneurysms and 20 (58%) unruptured aneurysms. Among the aneurysms included, 2 (5%) were located in the supraclinoid ICA, 11 (30%) in the intracavernous ICA, 5 (15%) in the MCA, 5 (15%) in the anterior communicating artery/anterior cerebral artery, 5 (15%) in the basilar artery, 5 (15%) in the
Discussion
In our series of patients with aneurysms treated with stent-assisted coiling, CE-MRA and 3D-TOF-MRA were less accurate than DSA for aneurysm remnant detection (κ = 0.36 for both) and were unable to evaluate vessel patency (κ nearly null).
Despite recent progress in neurovascular device manufacturing, MR imaging of a stents remains difficult because current MRA sequences suffer from physical limitations such as magnetic susceptibility artefact, Faraday cage effect, insufficient through-slice
Conclusion
After stent-assisted coiling treatment, 3D-TOF-MRA and CE-MRA demonstrated good accuracy to detect aneurysm remnant (but tended to overestimate them). Even if CE-MRA agreement with DSA was better, there was no statistical difference between 3D-TOF-MRA and CE-MRA accuracies. Both MRA sequences were unable to provide a precise assessment of vessel anomalies but could only detect parent vessel occlusion. Further studies with improved 3D or 4D-MRA and CTA are necessary to ameliorate these
Disclosure of interest
The authors declare that they have no competing interest.
References (34)
- et al.
International subarachnoid aneurysm trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised comparison of effects on survival, dependency, seizures, rebleeding, subgroups, and aneurysm occlusion
Lancet
(2005) Flow diverter stents in the treatment of intracranial aneurysms: where are we?
J Neuroradiol
(2011)- et al.
Results of embolization used as the first treatment choice in a consecutive nonselected population of ruptured aneurysms: clinical results of the Clarity GDC study
Neurosurgery
(2011) - et al.
Immediate clinical outcome of patients harboring unruptured intracranial aneurysms treated by endovascular approach: results of the ATENA study
Stroke
(2008) - et al.
Safety and efficacy of balloon remodelling technique during endovascular treatment of intracranial aneurysms: critical review of the literature
AJNR Am J Neuroradiol
(2012) - et al.
Stent-assisted coiling of intracranial aneurysms: predictors of complications, recanalization, and outcome in 508 cases
Stroke
(2013) - et al.
Wide-necked intracranial aneurysms: treatment with stent-assisted coil embolization during acute (< 72 hours) subarachnoid hemorrhage – experience in 61 consecutive patients
Radiology
(2009) - et al.
Endovascular treatment of intracranial aneurysms: current status
Stroke
(2013) - et al.
Follow-up of intracranial aneurysms treated with detachable coils: comparison of gadolinium-enhanced 3D time-of-flight MR angiography and digital subtractionangiography
Radiology
(2001) - et al.
Follow-up of intracranial aneurysms selectively treated with coils: Prospective evaluation of contrast-enhanced MR angiography
AJNR Am J Neuroradiol
(2006)
MR angiography in the follow-up of intracranial aneurysms treated with Guglielmi detachable coils: systematic review and meta-analysis
Neuroradiology
Meta-analysis on diagnostic accuracy of MR angiography in the follow-up of residual intracranial aneurysms treated with guglielmi detachable coils
Interv Neuroradiol
MRA versus DSA for follow-up of coiled intracranial aneurysms: a meta-analysis
AJNR Am J Neuroradiol
Complications of diagnostic cerebral angiography: evaluation of 19,826 consecutive patients
Radiology
Follow-up of coiled intracranial aneurysms: comparison of 3D time-of-flight MR angiography at 3 T and 1.5 T in a large prospective series
AJNR Am J Neuroradiol
Follow-up of coiled intracranial aneurysms: comparison of 3D time-of-flight and contrast-enhanced magnetic resonance angiography at 3 T in a large, prospective series
Eur Radiol
Imaging follow-up of intracranial aneurysms treated by endovascular means: why, when, and how?
Stroke
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