Original article
Follow-up of intracranial aneurysms treated with stent-assisted coiling: Comparison of contrast-enhanced MRA, time-of-flight MRA, and digital subtraction angiography

https://doi.org/10.1016/j.neurad.2016.10.004Get rights and content

Summary

Background and purpose

Data about non-invasive follow-up of aneurysm after stent-assisted coiling is scarce. We aimed to compare time-of-flight (TOF) magnetic resonance angiography (MRA) (3D-TOF-MRA) and contrast-enhanced MRA (CE-MRA) at 3-Tesla, with digital subtraction angiography (DSA) for evaluating aneurysm occlusion and parent artery patency after stent-assisted coiling.

Materials and methods

In this retrospective single-center study, patients were included if they had an intracranial aneurysm treated by stent-assisted coiling between March 2008 and June 2015, followed with both MRA sequences (3D-TOF-MRA and CE-MRA) at 3-Tesla and DSA, performed in an interval < 48 hours.

Results

Thirty-five aneurysms were included. Regarding aneurysm occlusion evaluation, agreement with DSA was better for CE-MRA (K = 0.53) than 3D-TOF-MRA (K = 0.28). Diagnostic accuracies for aneurysm remnant depiction were similar for 3D-TOF-MRA and CE-MRA (P = 1). Both 3D-TOF-MRA (K = 0.05) and CE-MRA (K = −0.04) were unable to detect pathological vessel compared to DSA, without difference in accuracy (P = 0.68). For parent artery occlusion detection, agreement with DSA was substantial for 3D-TOF-MRA (K = 0.64) and moderate for CE-MRA (K = 0.45), with similar good diagnostic accuracies (P = 1).

Conclusion

After stent-assisted coiling treatment, 3D-TOF-MRA and CE-MRA demonstrated good accuracy to detect aneurysm remnant (but tended to overestimation). Although CE-MRA agreement with DSA was better, there was no statistical difference between 3D-TOF-MRA and CE-MRA accuracies. Both MRAs were unable to provide a precise evaluation of in-stent status but could detect parent vessel occlusion.

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:

  • 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)

  • A.J. Molyneux 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)
  • L. Pierot

    Flow diverter stents in the treatment of intracranial aneurysms: where are we?

    J Neuroradiol

    (2011)
  • C. Cognard 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)
  • L. Pierot et al.

    Immediate clinical outcome of patients harboring unruptured intracranial aneurysms treated by endovascular approach: results of the ATENA study

    Stroke

    (2008)
  • L. Pierot 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)
  • N. Chalouhi et al.

    Stent-assisted coiling of intracranial aneurysms: predictors of complications, recanalization, and outcome in 508 cases

    Stroke

    (2013)
  • O.I. Tahtinen 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)
  • L. Pierot et al.

    Endovascular treatment of intracranial aneurysms: current status

    Stroke

    (2013)
  • A. Boulin 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)
  • L. Pierot et al.

    Follow-up of intracranial aneurysms selectively treated with coils: Prospective evaluation of contrast-enhanced MR angiography

    AJNR Am J Neuroradiol

    (2006)
  • T.C. Kwee et al.

    MR angiography in the follow-up of intracranial aneurysms treated with Guglielmi detachable coils: systematic review and meta-analysis

    Neuroradiology

    (2007)
  • H.H. Weng et al.

    Meta-analysis on diagnostic accuracy of MR angiography in the follow-up of residual intracranial aneurysms treated with guglielmi detachable coils

    Interv Neuroradiol

    (2008)
  • M.J. Van Amerongen et al.

    MRA versus DSA for follow-up of coiled intracranial aneurysms: a meta-analysis

    AJNR Am J Neuroradiol

    (2014)
  • T.J. Kaufmann et al.

    Complications of diagnostic cerebral angiography: evaluation of 19,826 consecutive patients

    Radiology

    (2007)
  • L. Pierot et al.

    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

    (2012)
  • L. Pierot et al.

    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

    (2012)
  • S. Soize et al.

    Imaging follow-up of intracranial aneurysms treated by endovascular means: why, when, and how?

    Stroke

    (2016)
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