Aneurysmal and Perianeurysmal Changes After Endovascular Treatment: from Inflammation to Microbleed. A Case Report

Risk factors for perianeurysmal vasogenic oedema (pavo) following embolization therapy: literature review

Perianeurysmal vasogenic oedema (PAVO) is a rare complication associated post-embolisation of intracranial aneurysms. The prevalence, risk factors predisposing to susceptibility, and pathologic mechanisms underlying this process are not clearly understood. Since this complication may be associated with poor clinical outcomes, the authors designed this study to describe possible risk factors, underlying mechanisms, and management of PAVO through published case reports. Developing a priori protocol according to PRISMA guidelines, we searched MEDLINE/PubMed, Embase and Web of Science to identify case studies and reports of adult patients with intracranial aneurysms who developed perianeurysmal oedema following coil embolization therapy. Data extracted from these studies included patient demographics, aneurysm characteristics, coil type, PAVO characteristics, treatment, and outcomes. Quality was assessed using a standardized tool. 21 eligible studies of acceptable quality were identified, comprising 40 unique cases from 9 countries. The mean patient age was 56.4 years and 25 (62.5%) were female. Aneurysm size ranged from 6 to 30 mm, with a mean size of 15.2 mm; only 6 (15%) of cases were giant intracranial aneurysm (≥ 25 mm). The more frequent locations of intracranial aneurysms associated with PAVO were the ICA (50%) and posterior circulation (32.5%), with 7.5% and 10% of cases occurring in MCA and anterior circulation, respectively. 16 cases (40%) were treated with bare platinum coils, and 14 (35%) with a combination of BPCs and bioactive coils; in 10 cases (25%), the coil type was not mentioned. PAVO presented between 0 days and 8 years of coil embolization, with 23 (57.5% cases) presenting symptomatically in relation to brain region affected. Management strategies for PAVO included conservative, steroids, re-embolization, clipping, stenting, parent artery occlusion either as monotherapy or as combination therapy. Of reported studies, 26 treated cases (65%) resolved, with 8 (20%) remaining stable, and 4 (10%) deteriorating. PAVO can be associated with small or large intracranial aneurysms, bare and bioactive platinum coils, and all regions of the intracranial circulation. The understanding of the risk factors of this complication lies in the underlying mechanisms, which will ultimately guide appropriate patient follow-up and subsequent optimal management.

Vessel-wall MRI in thunderclap headache: A useful tool to answer the riddle?

BACKGROUND

Finding an intracranial aneurysm (IA) during a thunderclap headache (TCH) attack, represents a problem because it is necessary to distinguish whether the aneurysm is responsible for the headache as a warning leak or as an incidental finding. High-Resolution Vessel-Wall (HRVW) MRI sequences have been proposed to assess the stability of the wall, as it permits to detect the presence of aneurysmal wall enhancement (AWE). In fact, AWE has been confirmed due to inflammation, recognizable preceding rupture.Case 1: A 37-year-old woman with a migraine more intense than her usual. A CTA revealed a 10 mm AComA aneurysm without subarachnoid hemorrhage (SAH) and HRVW-MRI excluded AWE. The patient's headache improved, and therefore, the aneurysm was considered an incidental finding, and the headache diagnosed as TCH attack. Subsequently, the aneurysm was surgically clipped, and typical migraine relapsed was reported at follow-up (FU).Case 2: A 67-year-old woman with no history of headaches underwent CTA for an abrupt onset of headache. A 7 mm right carotid-ophthalmic aneurysm with no sign of SAH was discovered. HRVW-MRI demonstrated AWE and thus, a TCH attack for a warning leak of an unstable wall was suspected. Endovascular coiling was immediately performed and at FU any further headache attack was reported.

CONCLUSIONS

HRVW-MRI is useful in case of finding aneurysm as the cause of headaches, particularly the TCH attack. In fact, HRVW-MRI could assess the stability of the aneurysms wall, allowing different patient management and eventually the aneurysmal treatment.