Retreatment strategies for recurrent and residual aneurysms after treatment with flow-diverter devices

The evaluation of the flow re-direction endoluminal device (FRED) for the treatment of selected intracranial aneurysms: a Polish multicenter study

This Polish multicenter study aims to evaluate the effectiveness and safety of the Flow Direction Endoluminal Device (FRED) in treating selected unruptured intracranial aneurysms. The FRED Poland Study was an observational, multicenter, prospective study conducted in 8 Polish investigational sites. Imaging results were independently assessed by a Corelab and adverse events were adjudicated by a Clinical Events Committee (CEC). Clinical results up to 24 months and anatomical results at 6-, 12- and 24-months post-treatment were reported. A total of 86 patients with 89 target aneurysms were enrolled between January 2016 and September 2017. Most aneurysms were located on the anterior circulation (93.2%, 83/89 aneurysms) with the majority (64.0%, 57/89) being small (< 10 mm) in size. Treatment was successfully performed in 86 out of 89 cases (96.6%). The permanent neurological morbidity rate was 3.6%, and the neurological mortality rate was 2.4%. Imaging follow-up at 6 months showed complete occlusion of the aneurysm in 64.9% of cases, increasing to 79.5% at 12 months and 85.5% at 24 months. This study offers a comprehensive overview of the flow diversion treatment approach, demonstrating that the FRED device is effective and safe for use in intracranial aneurysm treatment. These results align with existing literature, reaffirming the device reliability and suitability for clinical use.

Efficacy and safety of flow diverters in retreatment of recurrent intracranial aneurysms-A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Treatment of recurrent intracranial aneurysms after their initial therapy has been a significant challenge in the field of neurointervention. Recently flow diverters stents are widely used for treating intracranial aneurysms. In this systematic review and meta-analysis, we assessed the safety and efficacy of flow diverter in treating recurrent or recanalized intracranial aneurysms.

METHODS

This meta-analysis is reported following the PRISMA 2020 guidelines. We conducted a systematic review of literature in the PubMed, Embase, Web of Sciences, and Scopus databases. Pooled prevalence and the corresponding 95% are calculated from extracted data using a random-effect model.

RESULTS

The systematic literature search included 21 studies involving 411 patients, with 135 (32.8%) being male and 276 (67.2%) being females with a total number of 447 aneurysms. The overall rate of adequate occlusion was 90.67% (95% CI: 84.23%-94.65%), and the rates were comparable between the surgery (93.48%), coiling (91.78%), and stenting (85.77%) groups. The overall pooled rate of complete occlusion was 81.80 (95% CI: 71.14%-89.13%). On doing a subgroup analysis, the complete occlusion rates were 89.68%, 84.39%, and 73.47% for the surgery, coiling, and stenting groups, respectively. The overall mortality rate and achieving modified Rankin scale score of 0-2 was 1.28% (95% CI: 0.45%-3.64%) and (95% CI: 89.92%-97.84%), respectively. No significant heterogeneity is noted in the included studies.

CONCLUSION

Flow diverter stents are an effective and safe method for retreating recurrent or residual intracranial aneurysms with a high rate of complete and adequate occlusion. The rate of mortality, intracerebral hemorrhage, and overall and procedural complications following using flow diverters for intracranial aneurysms is low.

Clipping of a persistent middle cerebral artery aneurysm after previous flow diverter placement: An illustrative case and review of the literature

Flow diverter (FD) is increasingly used in the management of wide necked cerebral aneurysms. Despite a reported lower efficacy in middle cerebral artery (MCA) aneurysms, they are still being utilised. Microsurgery is best considered as an index treatment, but can also be a safe and effective treatment when encountering a persistent MCA aneurysm after prior FD. As there is a paucity in literature and more cases of failed FD are expected to appear, we want to add our experience to the existing literature. The microsurgical management of a persistent MCA bifurcation aneurysm, 3 years after a p48 MW HPC Flow Diverter (phenox GmbH, Bochum Germany) insertion is reported and the relevant literature discussed.

Treatment Outcome of Flow Diverter Device for Medium-Sized Cerebral Aneurysms: A Single-Center Report

Objective

Flow diverters (FDs), first introduced in Japan in 2015, were initially limited to wide-necked large cerebral aneurysms, which pose a high treatment risk. However, based on the results of the PREMIER study, the indications have expanded since 2020, and the number of treatment cases is increasing in Japan. At our hospital, FD placement with adjunctive coil embolization has been actively performed for medium-sized cerebral aneurysms, as indicated in the PREMIER study; herein, we report the outcomes of this treatment.

Methods

Of the 25 patients with 28 aneurysms who underwent FD placement at our institution between April 2022 and June 2023, 15 with 17 wide-necked unruptured cerebral aneurysms with a maximum diameter of <12 mm in the internal carotid artery (ICA) or vertebral artery (VA) were included. Postoperative complications were investigated in each case, and the aneurysm occlusion status was assessed using ultrashort echo time (UTE)-MRA at 3 months postoperatively and angiography at 6 months postoperatively. Fifteen patients who underwent coiling or stent-assisted coiling (SAC) for the same criteria during the same period were compared. Baseline characteristics and treatment results were compared between FD and coiling/SAC cases.

Results

Four males and 11 females with a mean age of 61.7 ± 12.8 years were included, and the median follow-up period was 9 months (6-18 months). There were 14 aneurysms of the ICA and 3 of the VA, and the mean maximum aneurysm diameter was 7.9 ± 1.7 mm. All patients were treated using the Pipeline Flex with Shield Technology (Medtronic, Minneapolis, MN, USA), and 14 aneurysms (82.4%) were treated with adjunctive coil embolization. There were no symptomatic strokes in the perioperative period; only one patient receiving corticosteroid therapy for thyroid eye disease had asymptomatic ICA occlusion at 3 months. Fifteen aneurysms (88.2%) were not visible on UTE-MRA at 3 months postoperatively, and angiography at 6 months showed complete occlusion in 16 (94.1%) aneurysms. The coiling/SAC group had a smaller neck size and higher volume embolization ratio than the FD group; however, complete occlusion was higher in the FD group.

Conclusion

FD placement with adjunctive coil embolization for medium-sized cerebral aneurysms is expected to result in good occlusion rates in the early postoperative period.

Repeat Flow Diversion for Retreatment of Incompletely Occluded Large Complex Symptomatic Cerebral Aneurysms: A Retrospective Case Series

BACKGROUND AND OBJECTIVES

Data regarding radiographic occlusion rates after repeat flow diversion after initial placement of a flow diverter (FD) in large intracranial aneurysms are limited. We report clinical and angiographic outcomes on 7 patients who required retreatment with overlapping FDs after initial flow diversion for large intracranial aneurysms.

METHODS

We performed a retrospective review of a prospectively maintained database of cerebrovascular procedures performed at our institution from 2017 to 2021. We identified patients who underwent retreatment with overlapping FDs for large (>10 mm) cerebral aneurysms after initial flow diversion. At last angiographic follow-up, occlusion grade was evaluated using the O'Kelly-Marotta (OKM) grading scale.

RESULTS

Seven patients (median age 57 years) with cerebral aneurysms requiring retreatment were identified. The most common aneurysm location was the ophthalmic internal carotid artery (n = 3) and basilar trunk (n = 3). There were 4 fusiform and 3 saccular aneurysms. The median aneurysm width was 18 mm; the median neck size for saccular aneurysms was 7 mm; and the median dome-to-neck ratio was 2.8. The median time to retreatment was 9 months, usually due to symptomatic mass effect. After retreatment, the median clinical follow-up was 36 months, MRI/magnetic resonance angiography follow-up was 15 months, and digital subtraction angiography follow-up was 14 months. Aneurysm occlusion at last angiographic follow-up was graded as OKM A (total filling, n = 1), B (subtotal filling, n = 2), C (early neck remnant, n = 3), and D (no filling, n = 0). All patients with symptomatic improvement were OKM C, whereas patients with worsened symptom burden were OKM A or B. Two patients required further open surgical management for definitive management of the aneurysm remnant.

CONCLUSION

Although most patients demonstrated a decrease in aneurysm remnant size, many had high-grade persistent filling (OKM grades A or B) in this subset of mostly large fusiform aneurysms. Larger studies with longer follow-up are warranted to optimize treatment strategies for atypical aneurysm remnants after repeat flow diversion.

Surgical Treatment Strategies for Residual or Recurrent Intracranial Aneurysms Following Endovascular Embolization

OBJECTIVE

To explore how to effectively manage the residual or recurrent intracranial aneurysms after embolization.

METHODS

The authors retrospectively reviewed our experience of endovascular interventional therapy, surgical clipping, and cerebrovascular bypass surgery in the treatment of residual or recurrent aneurysms after embolization at the authors' institution from 2018 to 2022.

RESULTS

The Glasgow Outcome Scale of 28 patients after the procedure and at discharge showed that 24 recovered well, 3 had severe disability, and 1 died. During the 24-month follow-up, 26 had a good recovery, 1 suffered from disability, and 1 died. Two cases of aneurysm recurrence were detected, and both were treated through endovascular therapy. Among them, 1 case underwent a repeat endovascular embolization, and 1 case was switched to surgical clipping. No residual aneurysms were observed in the remaining patients who underwent bypass surgery, and their bypass grafts were all patent.

CONCLUSION

Based on the clinical status of patients, aneurysmal characteristics, surgical risk, and possibility of rerupture of aneurysms, an individualized strategy was proposed for residual or recurrent aneurysms after embolization. The use of endovascular interventional therapy or surgical clipping can be safely and effectively managed, and cerebrovascular bypass surgery can effectively manage complex aneurysms.

Flow diverter retreatment for intracranial aneurysms: A meta-analysis of efficacy and feasibility

BACKGROUND

Recurrent intracranial aneurysm carries a risk of rupture and retreatment is often necessary. However, there is no consensus on the best retreatment modality of choice. Flow diverter has emerged as a promising option for this population in recent years. Given its high cost, patient selection to optimize outcomes is very important.

PURPOSE

To identify patient factors predisposing to failure of flow diverter retreatment.

METHOD

We conducted a systematic search on PubMed, Cochrane Library, Embase, Ovid/Medline, and ClinicalTrial.gov from 2000 to 2021. Studies regarding flow diverter retreatment of recurrent aneurysms were analyzed if they meet the inclusion criteria.

RESULTS

A total of twenty-six studies were identified. Among 374 patients retreated with flow diverters, about 0.86 [0.81; 0.92] were successfully occluded and only 0.06 [0.02; 0.10] had unfavorable neurological outcomes. Major complications included intracranial hemorrhage (n = 7), ischemic stroke or thromboembolic event (n = 12), and death (n = 2). In-stent stenosis was reported in 10 of the cases. Saccular aneurysms are associated with a higher occlusion rate while aneurysm location, size, status, and prior treatment modality have no significant impact on retreatment efficacy.

CONCLUSIONS

We demonstrated that flow diverter is an effective retreatment strategy except in patients with non-saccular aneurysms. It should be considered as a first-line option for patients with recurrent intracranial aneurysm.

Retreatment of previously flow diverted intracranial aneurysms with the pipeline embolization device

BACKGROUND AND PURPOSE

Flow diversion of intracranial aneurysms with the Pipeline Embolization Device (PED) is frequently performed, but the outcomes of retreatment for aneurysms that failed to occlude after prior treatment with PED have not been well studied. Here, we report the safety and efficacy of PED retreatment after initial failure to occlude.

MATERIALS AND METHODS

Clinical and angiographic data from eligible patients were retrospectively assessed for demographics, aneurysm occlusion status, and clinical outcomes. Patients were included in this study if they underwent PED retreatment to treat an aneurysm that had previously been treated with PED.

RESULTS

Retreatment of previously flow-diverted aneurysms with PED was performed in 42 cases. At final angiographic follow-up, angiographic improvement was observed after 45% (19/42) of retreatments and complete aneurysm occlusion was observed following 26% (11/42). Significant clinical complications occurred in 10% (4/42) of PED retreatments.

CONCLUSIONS

Retreatment of intracranial aneurysms with PED following initial failure to achieve aneurysm occlusion has a low rate of subsequent complete aneurysm occlusion.

Transradial Stent-Assisted Coiling Using "Dual-Jailing" Technique for Kissing Aneurysms of the Internal Carotid Artery: Technical Note and Literature Review

BACKGROUND

Kissing aneurysms are an unusual type of multiple intracranial aneurysms having different origins with partially adherent walls. Although endovascular treatment is a useful alternative to surgical clipping, endovascular management for small wide-necked kissing aneurysms has not been adequately investigated to date. Herein, we present a case of small wide-necked kissing aneurysms successfully treated with transradial stent-assisted coiling (SAC) using the "dual-jailing" technique. We also performed a review of the relevant literature.

CASE PRESENTATION

A 64-year-old woman who was diagnosed with small wide-necked kissing aneurysms relating to the ophthalmic artery underwent SAC using the dual-jailing technique. After a 6F Simmons guiding sheath was delivered into the target common carotid artery via transradial access, a 6F intermediate catheter was navigated into the petrous internal carotid artery to achieve both triple microcatheter manipulation and contrast injection. Two coil-delivery microcatheters were cannulated into each aneurysm, followed by a Neuroform Atlas stent deployment over the aneurysm necks via a third stent-delivery microcatheter. By using the jailed microcatheters, SAC of the kissing aneurysms was successfully achieved, preserving the ophthalmic artery. The postprocedural course was uneventful. A follow-up magnetic resonance angiography showed no evidence of recanalization 2 years 3 months post procedure.

CONCLUSIONS

The dual-jailing technique may provide simple and time-saving SAC compared with previous reported method. This technique can be a useful treatment option for small wide-necked kissing aneurysms.

Flow alteration therapy for impending rupture of intracranial giant aneurysm after flow diverter placement

Background:

Flow diverter (FD) placement is generally effective for intractable internal carotid artery (ICA) aneurysms. However, salvage treatment for the aneurysm enlarging even after FD placement remains to be elucidated. Additional overlapping FD placement is considered the first-line treatment for residual or recurrent aneurysms. However, it is unclear whether overlapping FD is also effective for enlarging giant aneurysms that are considered impending rupture status. Although parent artery occlusion is a promising option, treatment strategy must be optimized, especially when a critical perforating artery is involved.

Case Description:

A 74-year-old woman experienced rapid symptomatic growth of her giant supraclinoid ICA aneurysm 10 months after FD placement. We assumed that reinforcement of flow diverting effect alone would be less effective for this extremely intractable aneurysm with more aggressive clinical feature so that surgical bailout by parent artery occlusion was planned. Complete ICA obliteration underneath the aneurysm was unavailable due to the presence of anterior choroidal artery. Thus, we took a flow alteration strategy, where we created minimal retrograde flow through the parent artery by a combination of an extracranial-intracranial bypass and targeted endovascular proximal parent artery obliteration, resulting in prevention of aneurysmal rupture and further growth.

Conclusion:

Impending rupture of the intracranial giant aneurysm after FD placement may be controllable with a tailor-made parent artery occlusion strategy even when a critical perforating artery is involved.

Retrospective analysis of intracranial aneurysms after flow diverter treatment including color-coded imaging (syngo iFlow) as a predictor of aneurysm occlusion

PURPOSE

Flow Diverters (FD) have immensely extended the treatment of cerebral aneurysms in the past years. Complete aneurysm occlusion is a process that often takes a certain amount of time and is usually difficult to predict. Our aim was to investigate different syngo iFlow parameters in order to predict aneurysm occlusion.

METHODS

Between 2014 and 2018 patients with unruptured cerebral aneurysms treated with a FD were reviewed. Aneurysm occlusion and complication rates have been assessed.In addition, various quantitative criteria were assessed using syngo iFlow before, after the intervention, and after short and long-term digital subtraction angiography (DSA).

RESULTS

A total of 66 patients hosting 66 cerebral aneurysms were included in this study. 87.9% (n = 58) aneurysms in the anterior and 12.1% (n = 8) in the posterior circulation were treated. Adequate aneurysm occlusion at long-term follow-up (19.05 ± 15.1 months) was achieved in 90.9% (n = 60). Adequately occluded aneurysm revealed a significantly greater peak intensity delay (PI-D, p = 0.008) and intensity decrease ratio (ID-R, p < 0.001) compared to insufficiently occluded aneurysms. Increased intra-aneurysmal contrast agent intensity (>100%) after FD implantation resulted in an ID-R < 1, which was associated with aneurysm growth during follow-up DSA. Retreatment with another FD due to foreshortening and/or aneurysm growth was performed in 10.6% (n = 7). Overall morbidity and mortality rates were 1.5% (n = 1) and 0%.

CONCLUSION

The applied syngo iFlow parameters were found to be useful in predicting adequate aneurysm occlusion and foresee aneurysm growth, which might indicate the implantation of another FD.