Post-embolization perianeurysmal edema revealed by temporal lobe epilepsy in a case of unruptured internal carotid artery aneurysm treated with bare platinum coils

Perianeurysmal vasogenic oedema (PAVO): A single centre 10-year retrospective review

INTRODUCTION

Perianeurysmal Vasogenic Oedema (PAVO) is a rare but important complication of endovascular treatment of intracranial aneurysms. Many potential risk factors have been identified including age, aneurysm size, aneurysm location, immunological profile, type of coil used, diabetes, hypertension, and smoking. PAVO can cause persistent post-procedural symptoms, subsequently increasing post-embolization morbidity.

METHODS

A 10-year retrospective review was conducted between 2011 and 2021 at Royal Preston Hospital, Preston, UK.

RESULTS

We identified 8 patients that fit our inclusion criteria. This included 6 (75%) females and 2 (25%) males. The mean age was 64. All patients had anterior circulation aneurysms with the middle cerebral artery (MCA) being the most common site. The mean aneurysm size was 12 mm. Our patients were managed with a range of endovascular techniques. One patient had pre-treatment PAVO while 7 patients had post-embolization PAVO. Five patients were symptomatic, and 3 cases were asymptomatic with only radiological evidence of PAVO. Five patients were managed with varying courses of dexamethasone. PAVO resolution was achieved in 4 cases. The oedema significantly improved in 3 cases, but transiently progressed in 1 case.

CONCLUSIONS

PAVO is a rare but important complication of endovascular management of intracranial aneurysms. We have shown that patients can be effectively managed with steroids with resultant oedema regression and symptomatic improvement. Many risk factors have been associated with PAVO, but further research is needed to better understand their role in PAVO development and help develop other therapeutic options.

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.

Case report: Unruptured small middle cerebral artery aneurysm with perianeurysmal edema

Background

Perianeurysmal edema (PAE) has a tendency to occur in embolized aneurysms but also in partially thrombosed, large, or giant aneurysms. However, there are only a few cases recorded in which PAE was detected in untreated or small aneurysms. We suspected that PAE might be an impending sign of aneurysm rupture in these cases. Herein, we presented a unique case of PAE that was related to an unruptured small middle cerebral artery aneurysm.

Case description

A 61-year-old woman was referred to our institute due to a newly formed abnormal fluid-attenuated inversion recovery (FLAIR) hyperintense lesion in the right medial temporal cortex. Upon admission, the patient did not present with any symptoms or complaints; however, FLAIR and CT angiography (CTA) suggested an increased risk of aneurysm rupture. Aneurysm clipping was conducted, and no evidence of subarachnoid hemorrhage and hemosiderin deposits around the aneurysm and brain parenchyma was noted. The patient was discharged home without any neurological symptoms. MRI taken at eight months post-clipping revealed complete regression of the FLAIR hyperintense lesion around the aneurysm.

Conclusion

PAE in unruptured, small aneurysm is thought to be an impending sign of aneurysm rupture. Early surgical intervention is critical even for small aneurysms with PAE.

Bailout Strategies and Complications Associated with the Use of Flow-Diverting Stents for Treating Intracranial Aneurysms

Background

Flow-diverting stents (FDS) have revolutionized the endovascular management of unruptured, complex, wide-necked, and giant aneurysms. There is no consensus on management of complications associated with the placement of these devices. This review focuses on the management of complications of FDS for the treatment of intracranial aneurysms.

Summary

We performed a systematic, qualitative review using electronic databases MEDLINE and Google Scholar. Complications of FDS placement generally occur during the perioperative period.

Key Message

Complications associated with FDS may be divided into periprocedural complications, immediate postprocedural complications, and delayed complications. We sought to review these complications and novel management strategies that have been reported in the literature.

Perianeurysmal vasogenic oedema (PAVO) following aneurysm embolisation: a unique case of asymptomatic long-term progression and review of the literature

Perianeurysmal vasogenic oedema is a recognised although rare phenomenon following endovascular treatment of certain intracranial aneurysms. We present a unique case of asymptomatic perianeurysmal vasogenic oedema following bare platinum coil embolisation of an incidentally discovered right middle cerebral artery aneurysm that slowly increased over a period of 6 years before stabilising and regressing. During this time, the coiled aneurysm per se remained completely stable on serial magnetic resonance angiography.

Analysis of risk factors for perifocal oedema after endovascular embolization of unruptured intracranial arterial aneurysms

Background

Endovascular embolization is a treatment of choice for the management of unruptured intracranial aneurysms, but sometimes is complicated with perianeurysmal oedema. The aim of our study was to establish incidence and outcomes of perianeurysmal oedema after endovascular coiling of unruptured intracranial aneurysms, and to reveal possible risk factors for development of this potentially serious complication.

Methods

In total 119 adult patients with endovascular embolization of unruptured intracranial aneurysm (performed at Department for Interventional Neuroradiology, Clinical Center, Kragujevac, Serbia) were included in our study. The embolizations were made by electrolite-detachable platinum coils: pure platinum, hydrophilic and combination of platinum and hydrophilic coils. Primary outcome variable was perianeurysmal oedema visualized by magnetic resonance imaging (MRI) 7, 30 and 90 days after the embolization.

Results

The perianurysmal oedema appeared in 47.6% of patients treated with hydrophilic coils, in 21.6% of patients treated with platinum coils, and in 53.8% of those treated with mixed type of the coils. The multivariate logistic regression showed that variables associated with occurrence of perianeurysmal oedema are volume of the aneurysm, hypertension, diabetes and smoking habit. Hypertension is the most important independent predictor of the perianeurysmal oedema, followed by smoking and diabetes.

Conclusions

The results of our study suggest that older patients with larger unruptured intracranial aneurysms, who suffer from diabetes mellitus and hypertension, and have the smoking habit, are under much higher risk of having perianeurysmal oedema after endovascular coiling.

PC400 volumetric coils minimize radiation, reduce procedure time and optimize packing density during endovascular treatment in medium sized cerebral aneurysms

BACKGROUND AND OBJECTIVES

The Penumbra Coil 400 (PC400) is designed to improve endovascular filling for intracranial aneurysms. The aim of this retrospective, single-operator study was to compare the use of the PC400 with conventional 0.010inch coils in procedure time, X-ray exposure and packing density.

METHODS

We collected data from 31patients with 6 to 10mm diameter aneurysms embolized using the PC400, from May 2012 to November 2013. This group was compared with a control group of 27patients treated with conventional 0.010inch coils by the same operator. In both groups, clinical events, number of coils used, duration and cost of procedure, time of fluoroscopy and packing density were studied.

RESULTS

No serious adverse events were found in either group. Asymptomatic prolapse of coil loop into the parent artery were noted in two patients. Number of coils used was 4.45/6.35 in PC400 and control groups, respectively. Duration of procedure was 29.8/49.2minutes respectively (P-value=0.0002), and time of fluoroscopy was 28/41minutes (P-value=0.0109). Total radiation was 6098/6876cGy.cm(2) respectively. Comparison of packing densities after the first coil showed respectively 22.7%/10.6%, and after the final imaging, 53%/28.5% (P-values<0.0001). Complete or near complete occlusion on follow-up at 3months was 100% for PC400 versus 92% in the control group. Using 0.010inch coils may result in a 56% increase in treatment cost.

CONCLUSION

PC400 coils save procedural time and time of fluoroscopy, are cost saving and allow dramatic improvement of packing density on final imaging.

A Ruptured Basilar Tip Aneurysm Showing Repeated Perianeurysmal Edema after Endovascular Coil Embolization: Case Report

The authors present an extremely rare case of a 48-year-old female who developed repeated perianeurysmal edema at 2, 9, and 16 weeks after endovascular coil embolization for the ruptured intracranial aneurysm. Interestingly, the mechanism for this edema could be different at each time point in this case; acute thrombosis formation, chemical inflammation, and aneurysm recanalization. We have to be aware of this potential complication in the long term after endovascular coil embolization for the intracranial aneurysm, especially with large size or buried into the brain parenchyma. The clinical implications of this case are discussed with a review of the literature.

Incidence of Seizures or Epilepsy After Clipping or Coiling of Ruptured and Unruptured Cerebral Aneurysms in the Nationwide Inpatient Sample Database: 2002-2007

BACKGROUND:

It is not clear whether treatment modality (clipping or coiling) affects the risk of seizures after treatment for cerebral aneurysms.

OBJECTIVE:

To determine whether there is an increased risk of seizures after clipping vs coiling.

METHODS:

Hospitalizations for clipping or coiling of ruptured and unruptured aneurysms were identified in the Nationwide Inpatient Sample Database for 2002 to 2007 by International Classification of Diseases 9th Revision codes for subarachnoid hemorrhage or unruptured cerebral aneurysm and codes for clipping or coiling. Clipping and coiling were compared for the combined primary endpoint of seizures or epilepsy. The analysis was adjusted for patient-specific and hospital-specific factors using generalized linear models with generalized estimated equations.

RESULTS:

There were 10 899 hospitalizations for ruptured aneurysms (6593 clipping, 4306 coiling), and 9686 hospitalizations for unruptured aneurysms (4483 clipping, 5203 coiling). For ruptured aneurysm patients, clipping had a similar incidence of seizures or epilepsy compared with coiling (10.7% vs 11.1%, respectively, adjusted odds ratio: 0.596; 95% confidence interval: 0.158-2.248; P = .445 after adjustment for patient-specific and hospital-specific factors). For unruptured aneurysm patients, clipping was associated with a significantly higher risk of seizures or epilepsy (9.2%) compared with coiling (6.2%) (adjusted odds ratio: 1.362; 95% confidence interval: 0.155-1.606; P &lt; .001 after adjustment for patient-specific and hospital-specific factors). Seizures or epilepsy were significantly associated with longer hospitalizations (P &lt; .01) and higher hospital charges (P &lt; .0001), except in coiled unruptured aneurysm patients, in which seizures or epilepsy were not significantly associated with hospital charges (P = .31).

CONCLUSION:

In unruptured cerebral aneurysm patients, clipping is associated with a higher risk of seizures or epilepsy.