Keywords

Patient

48-year-old, female, spontaneous SAH, Hunt and Hess I, Fisher I

Diagnostic Imaging

A NCCT was done on day five after the onset of clinical symptoms and was within normal limits (Fig. 1).

Fig. 1
figure 1

Axial NCCT with no abnormal findings

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Treatment Strategy

The goal of the treatment was the prevention of a recurrent SAH .

Treatment

Procedure, 11.01.2016: endovascular treatment of a ruptured paraophthalmic blister aneurysm using flow diversion

Anesthesia: general anesthesia; 3000 IU unfractionated heparin (Heparin-Natrium, B. Braun) IV, 3 × 1 mg glycerol trinitrate (Nitrolingual infus., Pohl Boskamp) IA, 1 × 5 ml eptifibatide (Integrilin, GlaxoSmithKline) IV, 1 × 500 mg ASA (Aspirin i.v., Bayer Vital) IV, 1 × 180 mg ticagrelor (Brilique, AstraZeneca) via a gastric tube during the angiography

Premedication: none

Access: right common femoral artery, 1 × 6F sheath (Terumo); guide catheter: 1 × 6F Heartrail II (Terumo); microcatheter: 1 × Excelsior XT27 (Stryker); microguidewire: 1 × Synchro2 0.014″ 200 cm (Stryker)

Implant: flow diverter: 1 × p64 3/15 mm (phenox)

Course of treatment: A Multiplate Analyzer test (Roche Diagnostics) confirmed significant dual platelet function inhibition. The right ICA and MCA were catheterized with an Excelsior XT27 over a Synchro2 0.014″ microguidewire. One 3/15 p64 was deployed in the paraophthalmic segment of the right ICA, covering the origin of the ophthalmic artery and the adjacent blister aneurysm. The final DSA run confirmed the patency of the ophthalmic artery with contrast medium stagnation inside the covered blister aneurysm (Fig. 2).

Fig. 2
figure 2

DSA (lateral view) after injection of the right ICA revealing a broad-based, blister-like aneurysm of the paraophthalmic segment of the right ICA (arrow) (a). Un-subtracted radiograph after deployment and prior detachment of a 3/15 mm p64 flow diverter (phenox), (b). Final DSA run after the detachment of the p64, (c). The blister aneurysm is completely covered by the implant

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Duration: 1st–9th DSA run: 24 min; fluoroscopy time: 9.5 min

Complications: none

Post medication: oral dual antiplatelet medication with 1 × 100 mg ASA PO daily and 2 × 90 mg ticagrelor PO daily for one year, followed by 1 × 100 mg ASA PO daily lifelong

Clinical Outcome

The postprocedural phase was uneventful, and the patient was discharged on the third day after the endovascular procedure.

Follow-up Examinations

The postprocedural cranial MRI showed no ischemic lesions or other procedurally related complications.

DSA follow-up examinations three months, nine months, two years, and three years after the treatment confirmed the complete obliteration of the blister aneurysm and patency of the parent vessel. The ophthalmic artery, covered by the p64 flow diverter, remained patent. The patient was and remained neurologically asymptomatic (mRS 0) (Fig. 3).

Fig. 3
figure 3

Follow-up DSA two years after the treatment. Injection of the right ICA confirmed the complete occlusion of the blister aneurysm as well as the patency of the parent vessel and the ophthalmic artery (blue ring)

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Discussion

Blister aneurysms, although small, can cause a severe SAH. They are typically located at the supraclinoid segment of the ICA (Ji et al. 2017; Linfante et al. 2017; Nishikawa et al. 2017). Treatment is difficult due to the extreme fragility, small size, and broad-based, ill-defined neck of these blood-blister like aneurysms (Ji et al. 2017; Ryan et al. 2017). Various treatment approaches – both endovascular and microsurgical – have been described in medical literature (Ji et al. 2017; Meling 2017). However, an optimal treatment method has not yet been identified. Endovascular treatment is possible with stent-assisted coil placement or, more recently, with just flow diversion (Aydin et al. 2015; Chalouhi et al. 2014; Chinchure et al. 2014; Nerva et al. 2015; Rouchaud et al. 2015; Yoon et al. 2014).

Rouchaud et al. (2015) performed a systematic literature review on the endovascular treatment options of patients with an acute SAH due to blister aneurysms. They could show that flow diversion is a safe and effective method with low complication rates, low rate of retreatment, and good clinical and anatomical outcomes. Similar results have been reported in the review of Peschillo et al. (2016) as well as from other papers (Chinchure et al. 2014; Nerva et al. 2015; Yoon et al. 2014) – highlighting that flow diversion of ruptured blister aneurysms might become the therapy of choice for these patients.

The major drawback of flow diverter implantation is the necessity of dual platelet inhibition. In the acute phase of an SAH, maintaining adequate platelet inhibition can be challenging due to potential factors such as thrombocytosis, blood transfusion, coagulation modulators, etc. It is therefore imperative to closely monitor the effectiveness of the antiplatelet regimen. Accurate dual platelet function inhibition is crucial in order to avoid ischemic complications. We therefore recommend continuing this for a year. In particularly critical situations, we would add either low molecular weight heparin or a direct oral anticoagulant (e.g., 2 × 110 mg dabigatran daily) to be administered for six weeks.

Another issue of dual antiplatelet inhibition in these patients is the risk of re-bleeding. Reports of re- rupture after FD treatment in the acute phase have been published (Mazur et al. 2016). This issue, however, seems to be an exception. In our experience, no patient has ever suffered re-bleeding or a re-rupture after flow diversion in the acute phase of an SAH. However, introducing an FD with antithrombogenic coating, meaning that only one antiplatelet medication would be needed, would significantly improve the management of these patients. To the best of our knowledge, there has so far only been one report in which a coated FD was used in a patient with an acute SAH (Hanel et al. 2017). In this case, an in-stent thrombosis of the coated FD occurred 10 days after the treatment, most likely due to inadequate platelet inhibition. Antithrombogenic FD coating is a promising approach. However, these new devices should be used carefully as clinical experience is sparse and more data is required.

Cross-References