Endovascular treatment of traumatic carotid pseudoaneurysm with Tubridge flow diverter: A case report

Abstract

Traumatic pseudoaneurysm is a rare lesion with a high risk of rupture, and represents one of the most difficult lesions to treat, either surgically or endovascularly. Herein, we describe the case of a 32-year-old man with a traumatic pseudoaneurysm of the internal carotid artery, which was treated by overlapped flow diverters (Tubridge). The patient recovered well, and the follow-up angiography at four months showed complete occlusion of the pseudoaneurysm and patency of the internal carotid artery and the ophthalmic artery.

Introduction

Traumatic cerebral pseudoaneurysms with a high risk of rupture and mortality¹ are mainly located in the cervical, cavernous sinus and petrous carotid segments of the internal carotid artery (ICA), with a reported incidence of nearly 1%.² Surgical or endovascular sacrifice of the parent vessels is the most common treatment, but has a high risk of periprocedural complications, while parent vessel reconstruction remains a technical challenge. Flow diverters (FD) with low porosity were well established as an alternative treatment of aneurysmal complex lesions and were used in the treatment of pseudoaneurysm in a few case reports. In this case report, we describe endovascular parent vessel reconstruction and traumatic pseudoaneurysm thrombosis with overlapped FD stents (Tubridge; MicroPort, Shanghai, P.R. China).

Case report

A 32-year-old man was injured in a traffic accident. The patient had a severe head injury and suffered blurred vision in the left eye. A computed tomography (CT) scan revealed a left frontal epidural haematoma, pneumocephalus and multiple fractures of the left maxillary sinus and the left optic canal (Figure 1(a) and (b)). The patient also experienced massive epistaxis and was treated with postnasal packing. Digital subtraction angiography (DSA) was performed and showed an anterior wall focal irregular dilatation of the intracavernous segment of the left ICA, leading to the diagnosis of a traumatic pseudoaneurysm (Figure 1(c)).

Figure 1.

(a) and (b) Initial post-traumatic computed tomography (CT) scan showed left frontal epidural haematoma, pneumocephalus and multiple fractures of the left maxillary sinus and the left optic canal. (c), (d), and (e) Digital subtraction angiography (DSA) showed an irregular pseudoaneurysm from the intracavernous segment of the internal carotid artery (ICA), and endovascular procedure was performed. (f) and (g) At the end of the procedure, the stagnation of the contrast agent within the aneurysm could be detected, and both stents opened well. (h) Ten days later, DSA showed a reduction in the size of the pseudoaneurysm. (i) and (j) Four months later, a follow-up angiography showed complete occlusion of the pseudoaneurysm and patency of the left ICA and the ophthalmic artery without in-stent stenosis.

Under general anaesthesia and through the transfemoral approach, an endovascular procedure was performed. The Allcock test was also performed and showed unsatisfactory compensation from the right ICA. A 6 F guiding catheter was introduced into the proximal ICA. The diameter of the supraclinoid segment of the ICA was 3.92 mm, and the cavernous sinus was 4.97 mm (Figure 1(d) and (e)). A 5.5 mm × 20 mm Tubridge stent was deployed across the pseudoaneurysm, and the angiography demonstrated contrast stasis within the aneurysm. Then, another 5.0 mm × 15 mm Tubridge stent was placed within the first stent, and the final control angiogram revealed further stasis. At the end of the procedure, both stents opened well (Figure 1(f) and (g)). No periprocedural complications occurred. Ten days later, the follow-up DSA showed a reduction in the size of the pseudoaneurysm (Figure 1(h)). Follow-up angiography at four months showed a complete resolution of the lesion and patency of the left ICA and ophthalmic artery without in-stent stenosis (Figure 1(i) and (j)). This patient experienced no new neurological complications during the follow-up period.

Due to the high risk of post-traumatic intracranial haemorrhage and the massive epistaxis, antiplatelet therapy was not administered prior to treatment. The patient received 5 µg/kg intravenous tirofiban (Grandpharma Company, Wuhan, P.R. China) within three minutes after deployment of the stent, with a maintenance dose of 0.075 µg/kg/min for six hours. Dual antiplatelet drugs such as clopidogrel and aspirin (300 mg each) overlapped with tirofiban infusion at six hours before the cessation of tirofiban. Then, the patient was administered aspirin (100 mg/day) and clopidogrel (75 mg/day) postoperatively for three months, followed by aspirin alone indefinitely.

Discussion

Traditionally, the most common option for pseudoaneurysm of the ICA is to sacrifice the parent vessels surgically or endovascularly. However, even if the patient can tolerate the balloon occlusion test, some patients still demonstrate delayed ischaemic events and neurological deficits.³ Nowadays, it is possible to exclude the pseudoaneurysm from the circulation and reconstruct the parent artery, including single or overlapped stent-assisted coiling and covered stents. However, stent-assisted coiling has the risk of follow-up recurrence and rerupture.⁴ The covered stent could lead to good clinical results.⁵ The available intracranial covered stents are Willis stents (MicroPort), which are of limited size, show poor compliance and could lead to endoleak without complete apposition and occlude the arterial branches.

A FD can reconstruct the parent artery and occlude the aneurysm by changing the blood flow and allowing for endoluminal reconstruction.⁶ FDs have been increasingly used for off-label treatment of intracranial complex aneurysms such as small aneurysms and blood blister-like aneurysms. The pseudoaneurysms had a high risk of rupture and promoting the formation of thrombus in pseudoaneurysm as soon as possible was very important to treatment. The FD could only slowly induce thrombosis in the aneurysm, and whether it was safe for the treatment of pseudoaneurysm was uncertain. Giorgianni et al.⁷ reported a post-traumatic pseudoaneurysm of the cavernous ICA with epistaxis using a FD stent (P64; Phenox, Bochum, Germany). The follow-up CT angiography showed complete resolution of the lesion and ICA patency. Giorgianni et al.⁸ also reported the treatment of post-traumatic bilateral anterior cerebral artery pseudoaneurysms with a Pipeline stent (ev3/Covidien, Irvine, CA). The angiographic investigations performed six months after the procedure showed a complete resolution of the two traumatic pseudoaneurysms. Amenta et al.¹ reported a traumatic carotid pseudoaneurysm with overlapped Pipeline stents. The four-month follow-up angiogram showed complete obliteration of the pseudoaneurysm and successful reconstruction of the ICA.

The Tubridge stent was a braided, self-expanding, stent-like device with flared ends and a high metal coverage (approximately 30–35%).⁹ The PARAT study¹⁰ showed a higher rate of large and giant aneurysm obliteration with the Tubridge stent than with Enterprise stent-assisted coiling. The Tubridge stent was designed with different structures according to various diameters. The small-sized Tubridge stent with a diameter of <3.5 mm is composed of 46 nitinol and 2 radio-opaque, platinum-iridium microfilaments. Comparatively, the large-sized stent with a diameter ≥3.5 mm is composed of 62 nitinol and 2 radio-opaque microfilaments. Compared to the Pipeline and other FDs, the Tubridge stent differs in many ways, such as the platinum-iridium material used for the radiopaque microfilaments and a decreased incidence of shortening.¹¹ Two Tubridge stents (both 5 mm in diameter) were used in this case, and they reduced the risk of aneurysm bleeding. The four-month follow-up showed complete occlusion of this lesion. It was noteworthy that a FD with high metal coverage could lead to parent vessel occlusion and impact the patency of the branches. Four months later, the follow-up DSA showed that the parent artery had mild intimal hyperplasia without in-stent stenosis and that the ophthalmic artery was patent. A longer follow-up was needed.

This study shows that the use of FDs is a possible treatment choice for traumatic pseudoaneurysms. However, future investigations into the utility of the FD in the treatment of traumatic pseudoaneurysm are necessary to define the feasibility, safety, efficacy and durability associated with this treatment option.

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: supported by National Key R&D Program of China (2016YFC1300700) and Natural Science Foundation of China (no. 81571118 and no. 81771264).