Partially Thrombosed Vertebral Artery Aneurysm With Wall Enhancement Treated by Stent-Assisted Coil Embolization -Case Report-

[Giant partially thrombosed aneurysm of the vertebral artery: a case report and literature review]

INTRODUCTION

Giant partially thrombosed aneurysms of the vertebral artery are recalcitrant to treatment by microsurgical trapping and thrombectomy. Application of endovascular interventions is limited due to substantial brainstem compression and cranial nerve neuropathy. Combined endovascular exclusion and microsurgical excision provides an approach to treatment of these lesions.

CLINICAL CASE

A 48-year-old female patient presented with progressive complaints of ataxia, diplopia in left lateral gaze, and dysphagia. Imaging studies (CT, MRI, angiography) revealed a giant partially thrombosed aneurysm of the right vertebral artery and pronounced brainstem compression.

TREATMENT

The initial phase of treatment involved endovascular occlusion of the vertebral artery and aneurysm trapping that did not lead to changes in the postoperative patient's neurological status. MRI demonstrated complete aneurysm thrombosis and a weak TOF signal in the vertebral artery near the proximal aneurysm neck region. Because of persistent brainstem compression, the patient underwent right suboccipital craniectomy and hemilaminectomy of the CI arch for aneurysm excision one week after endovascular occlusion. After isolating the aneurysmal sac, the vertebral artery was transected, and two small branches extending from the aneurysm neck to the brainstem were also coagulated and transected, followed by aneurysm excision. Numerous vasa vasorum in the wall of the proximal vertebral artery and aneurysm neck were coagulated to stop bleeding. After surgery, the patient developed neurological symptoms (right leg ataxia and dysphagia worsening) due to lateral medullary infarction (confirmed by MRI) that presumably resulted from coagulation of two small perforating branches coming from the aneurysm neck to the brainstem. Recovery of the patient's neurological functions was observed during conservative treatment. The patient was discharged with mild right leg ataxia and preoperative left-sided abducens paresis.

CONCLUSION

Medulla oblongata compression associated with a giant thrombosed aneurysm of the vertebral artery can be eliminated by endovascular trapping followed by surgical excision of the aneurysm. Preserving the vasa vasorum feeding the brainstem is crucial for prevention of ischemic complications.

Stent-assisted coil embolization for cavernous carotid artery aneurysms

Internal carotid artery (ICA) occlusion with or without a bypass surgery is the traditional treatment for cavernous sinus (CS) aneurysms with cranial nerve (CN) dysfunction. Coil embolization without stents frequently requires retreatment because of the large size of CS aneurysms. We report the mid-term results of six unruptured CS aneurysms treated with stent-assisted coil embolization (SACE). The mean age of the patients was 72 years. The mean size of the aneurysms was 19.8 mm (range: 13–26 mm). Before treatment, four patients presented with CN dysfunction and two patients had no symptoms. SACE was performed under local or general anesthesia in three patients each. Mean packing density was 29.1% and tight packing was achieved. There were no neurological complications. CN dysfunction was cured in three patients (75%) and partly resolved in one patient (25%). Transient new CN dysfunction was observed in two patients (33%). Clinical and imaging follow-up ranged from 6 to 26 months (median: 16 months). Recanalization was observed in three patients (50%; neck remnant in two patients and dome filling in one patient), but no retreatment has yet been required. No recurrence of CN dysfunction has occurred yet. In summary, SACE increases packing density and may reduce requirement of retreatment with an acceptable cure rate of CN dysfunction. SACE may be a superior treatment for coiling without stents and be an alternative treatment of ICA occlusion for selected patients, such as older patients and those who require a high-flow bypass surgeryor cannot receive general anesthesia.