Transradial versus transfemoral access routes for diagnostic cerebral angiography: a large single-center comparative cost-analysis study

OBJECTIVE

Recently, the transradial (TR) approach has become a common alternative because of its safety profile and increased patient satisfaction compared with the transfemoral (TF) route. Both routes are associated with their respective associated costs, and differences typically emerge on the basis of patient anatomy, operator expertise, and occurrence of complications. The authors' objective was to compare the overall costs of diagnostic cerebral angiography via both routes and to shed light on the individual equipment costs of each route.

METHODS

This retrospective single-center study of 926 elective diagnostic angiograms was performed between December 2019 and March 2022.

RESULTS

The study comprised of 314 and 612 angiograms performed through the TF and TR routes, respectively. A significantly greater proportion of female patients were included in the TF cohort (79.3% vs 67.8%, p < 0.001), and most other demographic characteristics and baseline modified Rankin Scale scores were comparable between cohorts. The overall cost of patients utilizing the TR route was comparable to that of the TF route (mean ± SD $12,591.80 ± $19,128.00 vs $12,789.50 ± 18,424.00, p = 0.88). However, the median cost of catheters was significantly higher in TR group ($55.20 vs $12.40, p = 0.03), while the median costs of closure devices ($87.00 vs $20.20 p < 0.001) and sheaths ($44.60 ± 11.3 vs $41.10 ± 3.10, p < 0.001) were significantly higher in the TF group.

CONCLUSIONS

Overall, the authors' study showed that the TR approach can be a less expensive option for patients undergoing diagnostic cerebral angiography, especially if complications occur. Future studies may corroborate these findings and potentially lead to the adoption of TR as a low-cost, efficient, gold-standard technique for cerebral angiography.

Comparison of PED/PED Flex and PED Shield in the treatment of unruptured intracerebral aneurysms

OBJECTIVE

The object of this study was to compare the efficacy and safety profile of the Pipeline embolization device (PED)/Pipeline Flex embolization device (PED Flex) with that of the Pipeline Flex embolization device with Shield Technology (PED Shield). After introducing the first-generation PED and the second-generation PED Flex with its updated delivery system, the PED Shield was launched with a synthetic layer of phosphorylcholine surface modification to reduce thrombogenicity.

METHODS

This is a retrospective review of unruptured aneurysms treated with PED/PED Flex versus PED Shield between 2017 and 2022 at the authors' institution. Patients with ruptured aneurysms, adjunctive treatment, failed flow diverter deployment, and prior treatment of the target aneurysm were excluded. Baseline characteristics were collected for all patients, including age, sex, past medical history (hypertension, hyperlipidemia, diabetes mellitus), smoking status, aneurysm location, and aneurysm dimensions (neck, width, height) and morphology (saccular, nonsaccular). The primary outcome was procedural and periprocedural complication rates.

RESULTS

The study cohort comprised 200 patients with 200 aneurysms, including 150 aneurysms treated with the PED/PED Flex and 50 treated with the PED Shield. With respect to intraprocedural and periprocedural complications, length of stay, length of follow-up, and functional outcome at discharge, there was no significant difference between the two cohorts. At the midterm follow-up, the rate of in-stent stenosis (PED/PED Flex: 14.2% vs PED Shield: 14.6%, p = 0.927), aneurysm occlusion (complete occlusion: 79.5% vs 80.5%, respectively; neck remnant: 4.7% vs 12.2%; dome remnant: 15.7% vs 7.3%; p = 0.119), and the need for retreatment (5.3% vs 0%, p = 0.097) were comparable between the two cohorts.

CONCLUSIONS

This study suggests that, as compared to first- and second-generation PED and PED Flex, the third-generation PED Shield offers similar rates of complications, aneurysm occlusion, and in-stent stenosis at the midterm follow-up.

Causes and Predictors of 30-Day Readmission in Patients With Stroke Undergoing Mechanical Thrombectomy: A Large Single-Center Experience

BACKGROUND AND OBJECTIVES

The 30-day readmission rate has emerged as a metric of quality care and is associated with increased health care expenditure. We aim to identify the rate and causes of 30-day readmission after mechanical thrombectomy and provide the risk factors of readmission to highlight high-risk patients who may require closer care.

METHODS

This is a retrospective study from a prospectively maintained database of 703 patients presenting for mechanical thrombectomy between 2017 and 2023. All patients who presented with a stroke and underwent a mechanical thrombectomy were included in this study. Patients who were deceased on discharge were excluded from this study.

RESULTS

Our study comprised 703 patients, mostly female (n = 402, 57.2%) with a mean age of 70.2 years ±15.4. The most common causes of readmission were cerebrovascular events (stroke [n = 21, 36.2%], intracranial hemorrhage [n = 9, 15.5%], and transient ischemic attack [n = 1, 1.7%]).Other causes of readmission included cardiovascular events (cardiac arrest [n = 4, 6.9%] and bradycardia [n = 1, 1.7%]), infection (wound infection postcraniectomy [n = 3, 5.2%], and pneumonia [n = 1, 1.7%]). On multivariate analysis, independent predictors of 30-day readmission were history of smoking (odds ratio [OR]: 2.2, 95% CI: 1.1-4.2) P = .01), distal embolization (OR: 3.2, 95% CI: 1.1-8.7, P = .03), decompressive hemicraniectomy (OR: 9.3, 95% CI: 3.2-27.6, P < .01), and intracranial stent placement (OR: 4.6, 95% CI: 2.4-8.7) P < .01).

CONCLUSION

In our study, the rate of 30-day readmission was 8.3%, and the most common cause of readmission was recurrent strokes. We identified a history of smoking, distal embolization, decompressive hemicraniectomy, and intracranial stenting as independent predictors of 30-day readmission in patients with stroke undergoing mechanical thrombectomy.

Predictors of occlusion, long-term outcomes, and safety in a cohort of 674 aneurysms treated with the Pipeline embolization device

OBJECTIVE

By providing a more physiological approach to the treatment of intracranial aneurysms, the Pipeline embolization device (PED) has revolutionized the endovascular treatment of aneurysms. Although there are many flow diverters on the market, the authors report their experience with the PED, the first flow diverter to be approved by the Food and Drug Administration. They aimed to assess the efficacy and safety of PED flow diversion for the treatment of a wide range of aneurysms, as well as to look at factors affecting occlusion.

METHODS

This is a retrospective study of a prospectively maintained database of patients treated with the PED between January 2011 and December 2019. Charts were reviewed for patient, aneurysm, and procedure characteristics. The primary outcomes of interest were complication rates, occlusion outcomes (O'Kelly-Marotta grading scale), and functional outcomes (modified Rankin Scale [mRS]). Secondary outcomes included predictors of incomplete occlusion at 6 and 24 months of follow-up.

RESULTS

The study cohort included 581 patients with 674 aneurysms. Most aneurysms (90.5%) were in the anterior circulation and had a saccular morphology (85.6%). Additionally, 638 aneurysms (94.7%) were unruptured, whereas 36 (5.3%) were acutely ruptured. The largest mean aneurysm diameter was 8.3 ± 6.1 mm. Complications occurred at a rate of 5.5% (n = 32). The complete occlusion rate was 89.3% at 24 months' follow-up, and 94.8% of patients had a favorable neurological outcome (mRS score 0-2) at the last follow-up. On multivariate analysis, predictors of incomplete aneurysm occlusion at 6 months were hypertension (OR 1.7, p = 0.03), previous aneurysm treatment (OR 2.4, p = 0.001), and increasing aneurysm neck diameter (OR 1.2, p = 0.02), whereas a saccular morphology was protective (OR 0.5, p = 0.05). Predictors of incomplete occlusion at 24 months were increasing aneurysm neck diameter (OR 1.2, p = 0.01) and previous aneurysm treatment (OR 2.3, p = 0.01).

CONCLUSIONS

The study findings are corroborated by those of previous studies and trials. The complete occlusion rate was 89.3% at 24 months' follow-up, with 94.8% of patients having favorable functional outcomes (mRS score 0-2). Aneurysm treatment before PED deployment and an increasing aneurysm neck diameter increase the risk of incomplete occlusion at 6 and 24 months.

The Rate and Predictors of 30-Day Readmission in Patients Treated for Unruptured Cerebral Aneurysms: A Large Single-Center Study

BACKGROUND AND OBJECTIVES

Numerous studies of various populations and diseases have shown that unplanned 30-day readmission rates are positively correlated with increased morbidity and all-cause mortality. In this study, we aim to provide the rate and predictors of 30-day readmission in patients undergoing treatment for unruptured intracranial aneurysms.

METHODS

This is a retrospective study of 525 patients presenting for aneurysm treatment between 2017 and 2022. All patients who were admitted and underwent a successful treatment of their unruptured intracerebral aneurysms were included in the study. The primary outcome was the rate and predictors of 30-day readmission.

RESULTS

The rate of 30-day readmission was 6.3%, and the mean duration to readmission was 7.8 days ± 6.9. On univariate analysis, factors associated with 30-day readmission were antiplatelet use on admission (odds ratio [OR]: 0.4, P = .009), peri-procedural rupture (OR: 15.8, P = .007), surgical treatment of aneurysms (OR: 2.2, P = .035), disposition to rehabilitation (OR: 9.5, P < .001), and increasing length of stay (OR: 1.1, P = .0008). On multivariate analysis, antiplatelet use on admission was inversely correlated with readmission (OR: 0.4, P = .045), whereas peri-procedural rupture (OR: 9.5, P = .04) and discharge to rehabilitation (OR: 4.5, P = .029) were independent predictors of 30-day readmission.

CONCLUSION

In our study, risk factors for 30-day readmission were aneurysm rupture during the hospital stay and disposition to rehabilitation, whereas the use of antiplatelet on admission was inversely correlated with 30-day readmission. Although aneurysm rupture is a nonmodifiable risk factor, more studies are encouraged to focus on the correlation of antiplatelet use and rehabilitation disposition with 30-day readmission rates.

Venous sinus stenting for idiopathic intracranial hypertension patients with functioning ventriculoperitoneal shunts: A case series

Idiopathic intracranial hypertension (IIH) is a disease defined by increased intracranial pressure and associated with a variety of symptoms ranging from headaches to tinnitus. Ventricular peritoneal shunting has been the mainstay treatment for patients with IIH. Although VPS's have shown efficacy in treating IIH, some patients complain of refractory symptoms even with functioning VPS's. Venus stenting has emerged as a new technique for treating these refractory symptoms. Despite the scarce literature pertaining its efficacy and safety profile, several small studies have shown promising results. In this case series, four patients with IIH complained of refractory symptoms despite functioning VPS's and were treated with venous stenting.

Safety of Mechanical Thrombectomy in Patients on Antiplatelet/Anticoagulation

BACKGROUND

Mechanical thrombectomy (MT) is performed in patients who are already on anticoagulation (AC)/antiplatelet therapy (AP). However, data are insufficient regarding MT's safety and efficacy profiles in these patients.

OBJECTIVE

Investigate the outcome of stroke patients already on anticoagulation/antiplatelet receiving MT.

METHODS

We included consecutive acute ischemic stroke patients treated with MT for 10 years (2012-2022) in a comprehensive stroke center. Baseline variables, efficacy (recanalization [Thrombolysis in Cerebral Infraction] ≥ 2b), good functional outcome (modified Ranking Scale ≤ 2 at 3 months), and safety (symptomatic intracranial hemorrhage [sICH], mortality rates) were evaluated. Additionally, we conducted a subgroup analysis of patients with prior single-AP versus DAPT.

RESULTS

Six hundred forty-six patients were included (54.5% women, median age 71 years), 84 (13%) were on AC, 196 (30.3%) on AP, and 366 (56.7%) in the control group. The AC and AP groups were older and had more comorbidities. sICH occurred in 7.3% of cases. There was no significant difference in sICH incidence across the groups. The AC group had a lower rate of intravenous thrombolysis (15.9%; P < 0.001), a higher rate of sICH (11.9% vs. AP 7.7% and control 6%; P = 0.172), and higher mortality at discharge (17.9% vs. AP 8.7% and control 10.4%; P = 0.07). However, the groups had similar functional outcomes and mortality rates at 3 months. Successful recanalization was achieved in 92.7% and was similar across groups. Multivariable logistic regression and the subgroup analysis (single-AP vs. dual AP) did not reveal statistically significant associations.

CONCLUSIONS

MT in patients with prior anticoagulation and AP presenting with acute ischemic strokeis feasible, effective, and safe.

A Comparison of Outcomes Between Transfemoral Versus Transradial Access for Carotid Stenting

BACKGROUND

The transradial (TR) approach has emerged as an alternative to the transfemoral (TF) approach in carotid artery stenting (CAS) because of its perceived benefits in access site complications and overall patient experience.

OBJECTIVE

To assess outcomes of TF vs TR approach for CAS.

METHODS

This is a retrospective single-center review of patients receiving CAS through the TR or TF route between 2017 and 2022. All patients with symptomatic and asymptomatic carotid disease who underwent attempted CAS were included in our study.

RESULTS

A total of 342 patients were included in this study: 232 underwent CAS through TF approach vs 110 through the TR route. On univariate analysis, the rate of overall complications was more than double for the TF vs TR cohort; however, this did not achieve statistical significance (6.5% vs 2.7%, odds ratio [OR] = 0.59 P = .36). The rate of cross-over from TR to TF was significantly higher on univariate analysis (14.6 % vs 2.6%, OR = 4.77, P = .005) and on inverse probability treatment weighting analysis (OR = 6.11, P < .001). The rate of in-stent stenosis (TR: 3.6% vs TF: 2.2%, OR = 1.71, P = .43) and strokes at follow-up (TF: 2.2% vs TR: 1.8%, OR = 0.84, P = .84) was not significantly different. Finally, median length of stay was comparable between both cohorts.

CONCLUSION

The TR approach is safe, feasible, and provides similar rates of complications and high rates of successful stent deployment compared with the TF route. Neurointerventionalists adopting the radial first approach should carefully assess the preprocedural computed tomography angiography to identify patients amenable to TR approach for carotid stenting.

The Impact of Weather and Mode of Transport on Outcomes of Patients With Acute Ischemic Stroke Undergoing Mechanical Thrombectomy

BACKGROUND

Efficient transfer to mechanical thrombectomy (MT)-capable centers is essential for patients with stroke. Weather may influence stroke risk, transportation, and outcomes.

OBJECTIVE

To investigate how weather affects stroke patient transfer and outcomes after MT.

METHODS

We retrospectively collected data for patients with stroke transferred from spoke to our hub hospital to undergo MT between 2017 and 2021. We examined associations between weather, transportation, and patient outcomes.

RESULTS

We included 543 patients with a mean age of 71.7 years. The median National Institutes of Health Stroke Score increased from 14 to 15 after transportation. The median modified Rankin Scale was 4 at discharge and 90 days, and 3 at the final follow-up (mean 91.7 days). Higher daily temperatures were associated with good outcome, whereas daily drizzle was associated with poor outcome. More patients were transferred by air when visibility was better, and by ground during heavier precipitation, higher humidity, rain, mist, and daily drizzle, fog, and thunder . Patient outcomes were not associated with transportation mode. Among the independent predictors of good outcome, none was a weather variable. Lower hourly relative humidity ( P = .003) and longer road distance ( P < .001) were independent predictors of using air transportation, among others.

CONCLUSION

During transportation, higher temperature was associated with good outcome, whereas daily drizzle was associated with poor outcome after MT. Although weather was associated with transportation mode, no differences in outcomes were found between transportation modes. Further studies are needed to modify transfer protocols, especially during cold and rainy days, and potentially improve outcomes.

Long-Term Follow-Up of Cerebral Aneurysms Completely Occluded at 6 Months After Intervention with the Woven EndoBridge (WEB) Device: a Retrospective Multicenter Observational Study

The Woven EndoBridge (WEB) device has been widely used to treat intracranial wide neck bifurcation aneurysms. Initial studies have demonstrated that approximately 90% of patients have same or improved long-term aneurysm occlusion after the initial 6-month follow up. The aim of this study is to assess the long-term follow-up in aneurysms that have achieved complete occlusion at 6 months. We also compared the predictive value of different imaging modalities used. This is an analysis of a prospectively maintained database across 13 academic institutions. We included patients with previously untreated cerebral aneurysms embolized using the WEB device who achieved complete occlusion at first follow-up and had available long-term follow-up. A total of 95 patients with a mean age of 61.6 ± 11.9 years were studied. The mean neck diameter and height were 3.9 ± 1.3 mm and 6.0 ± 1.8 mm, respectively. The mean time to first and last follow-up was 5.4 ± 1.8 and 14.1 ± 12.9 months, respectively. Out of all the aneurysms that were completely occluded at 6 months, 84 (90.3%) showed complete occlusion at the final follow-up, and 11(11.5%) patients did not achieve complete occlusion. The positive predictive value (PPV) of complete occlusion at first follow was 88.4%. Importantly, this did not differ between digital subtraction angiography (DSA), magnetic resonance angiography (MRA), or computed tomography angiography (CTA). This study underlines the importance of repeat imaging in patients treated with the WEB device even if complete occlusion is achieved short term. Follow-up can be performed using DSA, MRA or CTA with no difference in positive predictive value.

The Effect of COVID-19 Vaccines on Stroke Outcomes: A Single-Center Study

BACKGROUND

One of the defining narratives of the COVID-19 pandemic has been the acceptance and distribution of vaccine. To compare the outcomes of COVID-19 positive vaccinated and unvaccinated stroke patients.

METHODS

This is a single-center retrospective study of COVID-19-vaccinated and unvaccinated stroke patients between April 2020 and March 2022. All patients presenting with stroke regardless of treatment modalities were included. National Institutes of Health Stroke Scale was used to assess stroke severity. The primary outcome was functional capacity of the patients at discharge.

RESULTS

The study cohort comprised 203 COVID-19 positive stroke patients divided into 139 unvaccinated and 64 fully vaccinated patients. At discharge, the modified Rankin scale score was significantly lower in the vaccinated cohort (3[1-4] vs. 4[2-5], odds ratio = 0.508, P = 0.011). At 3 months of follow-up, the median modified Rankin scale score was comparable between both cohorts.

CONCLUSIONS

Although vaccination did not show any significant difference in stroke patient outcomes on follow-up, vaccines were associated with lower rates of morbidity and mortality at discharge among stroke patients during the pandemic.

Comparison of Flow-Redirection Endoluminal Device and Pipeline Embolization Device in the Treatment of Intracerebral Aneurysms

BACKGROUND

The use of flow diverters for treating intracranial aneurysms has been widely used in the past decade; however, data comparing pipeline embolization device (PED; Medtronic Inc) and flow-redirection endoluminal device (FRED; MicroVention) in the treatment of intracranial aneurysms remain scarce.

OBJECTIVE

To compare the outcomes of PED and FRED in the treatment of intracranial aneurysms.

METHODS

This is a single-center retrospective review of aneurysms treated with PED and FRED devices. Patients treated with PED or FRED were included. Cases requiring multiple or adjunctive devices were excluded. Primary outcome was complete aneurysm occlusion at 6 months. Secondary outcomes included good functional outcome, need for retreatment, and any complication.

RESULTS

The study cohort comprised 150 patients, including 35 aneurysms treated with FRED and 115 treated with PED. Aneurysm characteristics including location and size were comparable between the 2 cohorts. 6-month complete occlusion rate was significantly higher in the PED cohort (74.7% vs 51.5%; P = .017) but lost significance after inverse probability weights. Patients in the PED cohort were associated with higher rates of periprocedural complications (3.5% vs 0%; P = .573), and the rate of in-stent stenosis was approximately double in the FRED cohort (15.2% vs 6.9%; P = .172).

CONCLUSION

Compared with PED, FRED offers modest 6-month occlusion rates, which may be due to aneurysmal and baseline patient characteristics differences between both cohorts. Although not significant, FRED was associated with a higher complication rate mostly because of in-stent stenosis. Additional studies with longer follow-up durations should be conducted to further evaluate FRED thrombogenicity.

Woven EndoBridge versus stent-assisted coil embolization of cerebral bifurcation aneurysms

OBJECTIVE

Stent-assisted coil (SAC) embolization has been the mainstay endovascular treatment for bifurcation aneurysms. The recent introduction of the Woven EndoBridge (WEB) device has presented an alternative endovascular treatment modality for these aneurysms. Direct comparisons of outcomes between these two modalities are limited in the literature. Here, the authors compared the outcomes of bifurcation aneurysms treated with SAC and WEB devices.

METHODS

This retrospective single-center study comprised 148 bifurcation aneurysms that were treated endovascularly with SAC or WEB devices between 2011 and 2019. The primary outcome was complete occlusion of the aneurysm at 6 months on catheter angiography.

RESULTS

The SAC and WEB cohorts comprised 85 and 63 aneurysms, respectively. The baseline characteristics were well balanced after inverse probability weight (IPW) adjustment, except for smoking status. The 6-month complete occlusion rate was higher in the WEB cohort than the SAC cohort (67.4% vs 40.6%; unadjusted OR [95% CI] 3.014 [1.385-6.563], p = 0.005). However, this difference in complete occlusion rates did not remain significant after IPW adjustment and multiple imputations. The neck remnant rate was lower in the WEB cohort than the SAC cohort (20% vs 50%; OR [95% CI] 0.250 [0.107-0.584], p = 0.001), and this difference remained significant after IPW adjustment (OR [95% CI] 0.304 [0.116-0.795], p = 0.015) and multiple imputations.

CONCLUSIONS

Use of SAC and WEB demonstrated comparable 6-month complete occlusion rates for bifurcation aneurysms. WEB appeared to be associated with a lower rate of neck remnant at 6 and 12 months compared with SAC. WEB was also associated with fewer complications and decreased retreatment rates compared with SAC.

Experience With Ventriculoperitoneal and Lumboperitoneal Shunting for the Treatment of Idiopathic Intracranial Hypertension: A Single Institution Series

BACKGROUND

CSF shunting is among the most widely utilized interventions in patients with idiopathic intracranial hypertension (IIH). Ventriculoperitoneal shunting (VPS) and lumboperitoneal shunting (LPS) are 2 possible treatment modalities.

OBJECTIVE

To evaluate and compare complications, malfunction, infection, and revision rates associated with VPS compared to LPS.

METHODS

Electronic medical records were reviewed to identify baseline and treatment characteristics for patients diagnosed with IIH treated with VPS or LPS.

RESULTS

A total of 163 patients treated with either VPS (74.2%) or LPS (25.8%) were identified. The mean follow-up was 35 mo. Shunt revision was required in 40.9% of patients. There was a nonsignificant higher rate of revision with LPS (52.4%) than VPS (36.4%, P = .07). In multivariate analysis, increasing patient age was associated with higher odds of shunt revision (P = .04). LPS had higher odds of shunt revision, yet this association was not significant (P = .06). Shunt malfunction was the main indication for revision occurring in 32.7%, with a significantly higher rate with LPS than VPS (P = .03). In total, 15 patients had shunt infection (9.4% VPS vs 12.2% LPS P = .50). The only significant predictor of procedural infection was the increasing number of revisions (P = .02).

CONCLUSION

The incidence of shunt revision was 40.9%, with increasing patient age as the sole predictor of shunt revision. The incidence of shunt malfunction was significantly higher in patients undergoing LPS, while there was no significant difference in the incidence of shunt infection between the 2 modalities.

Predictors of ventriculostomy infection in a large single-center cohort

OBJECTIVE

External ventricular drain (EVD) placement is a common neurosurgical procedure. While this procedure is simple and effective, infection is a major limiting factor. Factors predictive of infection reported in the literature are not conclusive. The aim of this retrospective, single-center large series was to assess the rate and independent predictors of ventriculostomy-associated infection (VAI).

METHODS

The authors performed a retrospective chart review of consecutive patients who underwent EVD placement between January 2012 and January 2018.

RESULTS

A total of 389 patients were included in the study. The infection rate was 3.1% (n = 12). Variables that were significantly associated with VAI were EVD replacement (OR 10, p = 0.001), bilateral EVDs (OR 9.2, p = 0.009), duration of EVD placement (OR 1.1, p = 0.011), increased CSF output/day (OR 1.0, p = 0.001), CSF leak (OR 12.9, p = 0.001), and increased length of hospital stay (OR 1.1, p = 0.002). Using multivariate logistic regression, independent predictors of VAI were female sex (OR 7.1, 95% CI 1.1–47.4; p = 0.043), EVD replacement (OR 8.5, 95% CI 1.44–50.72; p = 0.027), increased CSF output/day (OR 1.01, 95% CI 1.0–1.02; p = 0.023), and CSF leak (OR 15.1, 95% CI 2.6–87.1; p = 0.003).

CONCLUSIONS

The rate of VAI was 3.1%. Routine CSF collection (every other day or every 3 days) and CSF collection when needed were not associated with VAI. The authors recommend CSF collection when clinically needed rather than routinely.

A comparative study of transradial versus transfemoral approach for flow diversion

PURPOSE

Data in neurointerventional literature is extremely limited regarding the safety and efficacy of flow diversion using transradial access (TRA). We aim to demonstrate the safety and efficacy of intracranial aneurysm treatment with the Pipeline Embolization Device (PED) using TRA compared to transfemoral access (TFA).

METHODS

We conducted a retrospective analysis of a prospectively maintained database and identified 79 consecutive patients who underwent neuroendovascular embolization for cerebral aneurysms using the PED from April 2018 through October 2019. Patients were divided into 2 groups: TRA (32 patients) and TFA (47 patients). A comparative analysis was performed between the two groups.

RESULTS

There was no significant difference in postoperative intracranial hemorrhage (p>.99), symptomatic ischemic stroke (p=.512), access site complications (p=.268), or other complications (p=.512). However, there was a significant increase in overall complications (14.9% vs. 0.0%, p=.038) and procedure duration (71.4 min ± 31.2 vs. 58.5 ± 20.3, p=.018) in the TFA group. There was no significant difference in complete occlusion at latest follow-up (19/25, 76.0% vs. 35/40, 87.5%; p=.311), 6-month follow-up (17/23, 73.9% vs. 33/38, 86.8%; p=.303), or 12-month follow-up (8/8, 100.0% vs. 5/6, 83.3%; p=.429). There was also no significant difference in rate of retreatment (p>.99), morbidity (p=.512), mortality (p>.99), latest follow-up (p=.985), or loss of follow-up (p=.298).

CONCLUSIONS

The feasibility and efficacy of flow diversion with the PED via TRA for the treatment of intracranial aneurysms is comparable to TFA. Widespread adoption of this approach may be facilitated by improvements in device navigation and manipulation via radial-specific engineering.

Battle-Tested Guidelines and Operational Protocols for Neurosurgical Practice in Times of a Pandemic: Lessons Learned from COVID-19

The COVID-19 outbreak has led to fundamental disruptions of health care and its delivery with sweeping implications for patients and physicians of all specialties, including neurosurgery. In an effort to conserve hospital resources, neurosurgical procedures were classified into tiers to determine which procedures have to be performed in a timely fashion and which ones can be temporarily suspended to aid in the hospital's reallocation of resources when equipment is scarce. These guidelines were created quickly based on little existing evidence, and thus were initially variable and required refinement. As the early wave can now be assessed in retrospect, the authors describe the lessons learned and the protocols established based on published global evidence to continue to practice neurosurgery sensibly and minimize disruptions. These operational protocols can be applied in a surge of COVID-19 or another airborne pandemic.

A comparison of dual-lumen balloon and simple microcatheters in the embolization of DAVFs and AVMs using onyx

Endovascular embolization of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs) has become the mainstay in treatment for these pathologies. Traditional techniques required the formation of a proximal plug of Onyx around the microcatheter prior to embolization to avoid reflux. Recently, dual-lumen balloon catheters have been introduced as a potential solution to this issue. We sought to compare our institutional experience with dual-lumen balloons to traditional microcatheters in the endovascular embolization of AVMs and DAVFs. A retrospective analysis of consecutive patients treated with Scepter between 2016 and 2020 was obtained. A control cohort treated with Marathon between 2012 and 2020 was also obtained. Variables collected included patient demographics, procedure times, pedicles treated, operative complications, obliteration rate, and retreatment rate. A total of 44 trial (30 DAVFs and 14 AVMs) and 25 control (15 DAVFs and 10 AVMs) subjects were identified. Average Scepter procedure times were 66.0 and 68.0 min for DAVFs and AVMs, respectively. Average Scepter volume of Onyx injected was 2.2 and 1.4 mL for DAVFs and AVMs, respectively. Complete angiographic occlusion Scepter rate was 86.7% and 50.0% for DAVFs and AVMs, respectively. The Scepter retreatment rate was 13.3% and 50.0% for DAVFs and AVMs, respectively. Predictors of angiographic occlusion included the number of pedicles (OR 0.54, 95%CI 0.30-0.97, p = 0.04). Predictors of retreatment included DAVF (OR 0.16, 95%CI 0.04-0.66, p = 0.01) and Marathon (OR 3.34, 95%CI 1.00-11.56, p = 0.05). Our study shows that dual-lumen balloon catheters are a viable option in the embolization of DAVFs and AVMs.

Cerebral ischemic and hemorrhagic complications of coronavirus disease 2019

BACKGROUND

The coronavirus disease 2019 is associated with neurological manifestations including stroke.

OBJECTIVES

We present a case series of coronavirus disease 2019 patients from two institutions with acute cerebrovascular pathologies. In addition, we present a pooled analysis of published data on large vessel occlusion in the setting of coronavirus disease 2019 and a concise summary of the pathophysiology of acute cerebrovascular disease in the setting of coronavirus disease 2019.

METHODS

A retrospective study across two institutions was conducted between 20 March 2020 and 20 May 2020, for patients developing acute cerebrovascular disease and diagnosed with coronavirus disease 2019. We performed a literature review using the PubMed search engine.

RESULTS

The total sample size was 22 patients. The mean age was 59.5 years, and 12 patients were female. The cerebrovascular pathologies were 17 cases of acute ischemic stroke, 3 cases of aneurysm rupture, and 2 cases of sinus thrombosis. Of the stroke and sinus thrombosis patients, the mean National Institute of Health Stroke Scale was 13.8 ± 8.0, and 16 (84.2%) patients underwent a mechanical thrombectomy procedure. A favorable thrombolysis in cerebral infarction score was achieved in all patients. Of the 16 patients that underwent a mechanical thrombectomy, the mortality incidence was five (31.3%). Of all patients (22), three (13.6%) patients developed hemorrhagic conversion requiring decompressive surgery. Eleven (50%) patients had a poor functional status (modified Rankin Score 3-6) at discharge, and the total mortality incidence was eight (36.4%).

CONCLUSIONS

Despite timely intervention and favorable reperfusion, the mortality rate in coronavirus disease 2019 patients with large vessel occlusion was high in our series and in the pooled analysis. Notable features were younger age group, involvement of both the arterial and venous vasculature, multivessel involvement, and complicated procedures due to the clot consistency and burden.

Early Multicenter Experience With the Neuroform Atlas Stent: Feasibility, Safety, and Efficacy

BACKGROUND

The Neuroform Atlas stent™ (by Stryker, Fremont, California) represents the most recent widely available upgrade to intracranial stenting, providing a laser cut open cell stent with a diameter of 3.0 to 4.5 mm that is delivered through an 0.017-inch microcatheter.

OBJECTIVE

To report our initial multicenter experience of the safety, efficacy, and feasibility of the Atlas stent used for treating aneurysms, as well as one case of intracranial stenosis and one carotid artery dissection as well as other pathologies.

METHODS

A retrospective multicenter study of subjects treated with Atlas stent during the period 2018 to 2019.

RESULTS

The total number of patients included in our analysis was 71 patients. The stent was utilized to treat 69 aneurysm cases. Of the aneurysms, 36% presented with acute rupture and 56% of the ruptured aneurysms were high grade. Mean aneurysm dimension was 7 mm with an average neck width of 4.1 mm. Around 30% had received prior treatment. Telescoping or Y-stent was used in 16% of cases. We did not observe any symptomatic major complications in our series. Asymptomatic major complications were seen in 7 patients (10.1%); technical complications occurred in 4.3%. Immediate modified Raymond-Roy-occlusion-outcome class I/II was observed in 87%, and this increased to 97.7% at latest follow-up, which was at 4 mo; 91.8% of patients achieved favorable clinical outcome, and mortality rate was 1.4%.

CONCLUSION

Our series demonstrates the safety, feasibility, and efficacy of the Atlas stent. The low complication rate and the high obliteration rate managing complex aneurysms, even in an acute ruptured setting, are notable.

Posterior circulation tandem occlusions: Classification and techniques

BACKGROUND

Posterior circulation tandem occlusions are poorly characterized in current literature. Data regarding endovascular approaches and outcomes in this patient subgroup is extremely limited.

METHODS

We conducted a retrospective analysis of a prospectively maintained database and identified 17 patients with posterior circulation tandem occlusions who underwent mechanical thrombectomy between 2014 and 2019.

RESULTS

Of 17 patients with posterior circulation tandem occlusion, the mean age was 55.76 ± 11.8 with 35.3% female. The mean NIHSS score on presentation was 17.2 ± 9.2. Tissue plasminogen activator was administered in 7 (41.2%) patients, stent-retrievers alone were used in 2 (11.8%), aspiration catheters alone were used in 2 (11.8%), a combination was used 12 (70.6%), and a self-expandable stent in 5 (29.4%). The mean number of device passes was 2.24 ± 2.02, recanalization failure occurred in 4 (23.5%) patients, the mean time from stroke onset to puncture was 6.9 ± 2.4 h, and the mean time from puncture to recanalization was 59.3 ± 26.6 min. Postprocedural symptomatic ICH occurred in 1 (5.9 %) patient, periprocedural ICH/SAH occurred in 2 (11.8%), periprocedural distal emboli occurred in 0 (0%), periprocedural vessel dissection occurred in 1 (5.9%), and periprocedural vessel perforation occurred in 1 (5.9%) patient. TICI score>2b was achieved in 13 (76.5%) patients. An improvement in NIHSS>3 at discharge occurred in 10 (58.8%) patients, and good outcomes (mRS score < 2) occurred in 7 (41.2%). The mean length of stay was 11.6 ± 12.2 days, and the mortality rate was 41.2%.

CONCLUSION

Endovascular intervention with mechanical thrombectomy is safe and feasible in patients with posterior circulation tandem occlusions.

The impact of the implementation of a mobile stroke unit on a stroke cohort

BACKGROUND

Mobile stroke units (MSUs), specialized ambulances with a built-in computed tomography (CT) scanner and telemedicine connected stroke team, have been on the rise in recent years largely due to the 'time is brain' concept. We aim to report our initial experience since establishing our MSU, the first unit in the Tri-state area, and assess its impact on the stroke standards of care timeline.

METHODS

We conducted a retrospective analysis of a prospectively maintained database of all MSU dispatched cases from August 2019 to March 2020.

RESULTS

Of 195 MSU responses, 101 were treated and transported by the MSU. The mean time (hr:mm) of dispatch to scene arrival was 0:07+0:03, scene arrival to CT start was 0:10+0:03, CT start to teleneuro start was 0:05+0:03, teleneuro start to scene departure was 0:06+0:05, scene departure to hospital arrival was 0:12+0:06, and hospital arrival to arterial puncture was 2:59+1:01. The mean time of dispatch to arterial puncture was 3:34+1:02. The mean teleneuro consult duration was 0:04+0:02. The mean time of last know well (LKW) to tPA administration was 1:28+0:48 with 4 (57.1 %) patients receiving tPA within 60 min of LKW and 5 (71.4 %) patients receiving tPA within 90 min. The mean time of dispatch to tPA was 0:37+0:09 and scene arrival to tPA administration was 0:28+0:07.

CONCLUSION

MSUs may expedite each step along the stroke standards of care. In theory, this should drastically improve functional outcomes. However, the impact on functional outcomes or reductions in stroke-related morbidity is still unknown.

Access Through the Anatomical Snuffbox for Neuroendovascular Procedures: A Single Institution Series

BACKGROUND

Distal transradial catheterization in the anatomic snuffbox is an alternate route of access that has started to gain consideration for neuroendovascular procedures.

OBJECTIVE

To assess the feasibility and outcomes and present our institution's experience in performing neuroendovascular procedures via distal transradial access (dTRA).

METHODS

We conducted a retrospective analysis and identified 120 patients who underwent consecutive neuroendovascular procedures via dTRA in the anatomic snuffbox. Data collection was performed on indication for procedure, sheath size, number of vessels selectively catheterized, fluoroscopy time, procedure duration, radiation exposure, conversion to femoral approach, access site complication, and procedure success.

RESULTS

Of 120 patients with an average age of 54.7 yr ± 14.7, 73 (60.8%) underwent diagnostic angiograms, 38 (31.7%) underwent follow-up angiograms, and 9 (7.5%) underwent therapeutic procedures. The overall mean number of vessels catheterized was 2.5 ± 0.1 per procedure, the mean procedure time was 68.3 min ± 43.4, the mean fluoroscopy time was 10.8 min ± 7.6, the mean contrast dose was 70.6 mL ± 39.1, and the mean radiation exposure was 27 672.2 mGycm2 ± 42 728.4. Successfully completed therapeutic procedures included aneurysm 1 (0.8%), arteriovenous malformation (AVM)/arteriovenous fistula/carotid cavernous fistula 7 (5.8%), and 1 (0.8%) other treatment. Three patients (2.5%) required adjunct transfemoral endovenous access for AVM embolization. Two minor complications (1.67%) were a local wrist hematoma and a radial artery vasospasm without any sequelae.

CONCLUSION

Distal radial artery catheterization in the anatomic snuffbox is a safe and effective access site to perform neuroendovascular procedures. Complications and conversion rate are low making it a safe alternative.

Coil Embolization of Wide-Neck Bifurcation Aneurysms via Shouldering and Framing: A Safe Alternative to Conventional Techniques

OBJECTIVE

Double stent-assisted coiling of wide-neck bifurcation aneurysms (WNBAs) can be technically challenging with high thromboembolic rates. Single stent-assisted coiling (SSAC) decreases procedural complexity and thromboembolic risk but increases risk of coil prolapse and recanalization. In this study, we present our institution's experience with SSAC of WNBA performed via a "shouldering" and "framing" with a single Atlas stent and a spherical 3-dimensional (3D) Stryker coil.

METHODS

A retrospective review of 35 patients who underwent SSAC of WNBA performed via a shouldering and framing with a single Atlas stent and a spherical 3D Stryker coil from 2018 to 2019. Data collection were performed on baseline demographics, clinical presentation, aneurysm characteristics, angiographic and functional outcomes, and perioperative and postoperative complications.

RESULTS

Of 35 patients, the mean age was 59.9 ± 11.6 years and 25/35 (71.4%) were women. The mean aneurysm diameter was 6.3 ± 3.4 mm, the mean neck size was 3.9 ± 1.3 mm, and the mean dome-to-neck ratio was 1.5 ± 0.6. Initial complete/near-complete occlusion was demonstrated in 30/35 (85.7%) patients. On angiographic follow-up at a mean of 6 months, 9/24 (37.5%) patients showed progressive thrombosis, 13/24 (54.2%) showed stable occlusion, and 2/24 (8.5) showed recanalization. Thromboembolic events occurred in 2/35 (5.7%) patients, intraoperative technical complications occurred in 2/35 (5.7%) patients, and access-site complications occurred in 2/35 (5.7%) patients. The were no cases of retreatment, rehemorrhage, or procedural-related permanent morbidity or mortality.

CONCLUSIONS

Coil embolization performed via shouldering with a single Atlas stent and framing with a spherical 3D Stryker coil is a feasible, safe, and effective neuroendovascular treatment for WNBAs.

Endovascular robotic: feasibility and proof of principle for diagnostic cerebral angiography and carotid artery stenting

Background

Robots in surgery aid in performing delicate, precise maneuvers that humans, with inherent physical abilities, may be limited to perform. The CorPath 200 system is FDA approved and is being implemented in the US for interventional cardiology procedures. CorPath GRX robotic-assisted platform is the next-generation successor of CorPath 200.

Objective

To discuss the feasibility and early experience with the use of the CorPath GRX robotic-assisted platform for neuroendovascular procedures, including transradial diagnostic cerebral angiograms and transradial carotid artery stenting.

Methods

The cases of 10 consecutive patients who underwent neuroendovascular robotic-assisted procedures between December 1, 2019 and December 30, 2019, are presented.

Results

Seven patients underwent elective diagnostic cerebral angiography, and three patients underwent carotid artery angioplasty and stenting using the CorPath GRX robotic-assisted platform. All procedures were performed successfully, and no complications were encountered. Conversion to manual control occurred in three diagnostic cases because of a bovine arch that was previously not known. The fluoroscopy time and the procedure time continued to improve with subsequent procedures as we streamlined the workflow.

Conclusion

This series demonstrates the early use of this technology. It could potentially be used in the near future for acute stroke interventions in remote geographic locations and in places where a neurointerventionalist is not available.

Embolectomy in Patient with Basilar Artery Occlusion and Poor Neurological Exam

Background: Acute basilar artery occlusion (BAO) is generally associated with a poor prognosis and mortality rates up to 85% in non-recanalized patients. Emergent recanalization is essential to improve outcomes in this patient subgroup. Objective: To show that good patient outcomes, modified Rankin score (mRS) 0-2, can be achieved in patients presenting with acute BAO and poor or no neurological exam. Methods: We retrospectively analyzed the hospital course of a patient presenting with acute BAO and absent brainstem reflexes who underwent emergent revascularization. Results: The patient was discharge with cranial nerve III palsy but was otherwise neurologically intact. Conclusions: Patients presenting with acute BAO and poor or no neurological exam should be considered for emergent endovascular intervention. Despite the high risk of morbidity and mortality, this subgroup of patients can still have good functional outcomes.

Acute ischaemic stroke interventions: large vessel occlusion and beyond

Care for acute ischaemic stroke is one of the most rapidly evolving fields due to the robust outcomes achieved by mechanical thrombectomy. Large vessel occlusion (LVO) accounts for up to 38% of acute ischaemic stroke and comes with devastating outcomes for patients, families and society in the pre-intervention era. A paradigm shift and a breakthrough brought mechanical thrombectomy back into the spotlight for acute ischaemic stroke; this was because five randomised controlled trials from several countries concluded that mechanical thrombectomy for acute stroke offered overwhelming benefits. This review article will present a comprehensive overview of LVO management, techniques and devices used, and the future of stroke therapy. In addition, we review our institution experience of mechanical thrombectomy for posterior and distal circulation occlusion.

Revascularization and functional outcomes after mechanical thrombectomy: an update to key metrics

OBJECTIVE

The advent of mechanical thrombectomy (MT) has become an effective option for the treatment of acute ischemic stroke in addition to tissue plasminogen activator (tPA). With recent advances in device technology, MT has significantly altered the hospital course and functional outcomes of stroke patients. The authors' goal was to establish the most up-to-date reperfusion and functional outcomes with the evolution of MT technology.

METHODS

The authors conducted a retrospective study of 403 patients who underwent MT for ischemic stroke at their institution from 2010 to 2017. They collected data on patient comorbidities, National Institutes of Health Stroke Scale (NIHSS) score on arrival, tPA administration, revascularization outcomes, and functional outcomes on discharge.

RESULTS

In 403 patients, the mean NIHSS score on presentation was 15.8 ± 6.6, with 195 (48.0%) of patients receiving tPA prior to MT. Successful reperfusion (thrombolysis in cerebral infarction score 2B or 3) was achieved in 84.4%. Hemorrhagic conversion with significant mass effect was noted in 9.9% of patients. The median lengths of ICU and hospital stay were 3.0 and 7.0 days, respectively. Functional independence (modified Rankin Scale score 0-2) was noted in 125 (31.0%) patients, while inpatient mortality occurred in 43 (10.7%) patients.

CONCLUSIONS

As MT has established acute ischemic stroke as a neurosurgical disease, there is a pressing need to understand the hospital course, hospital- and procedure-related complications, and outcomes for this new patient population. The authors provide a detailed account of key metrics for MT with the latest device technology and identify the predictors of unfavorable outcomes and inpatient mortality.

Flow diversion for small caliber vessel aneurysms: efficacy, safety, and functional outcome

BACKGROUND

Flow-diverting stents had gained prominence among neurointerventionalists. Aneurysms originating from distal vessels, particularly dissecting or fusiform, pose more technical challenges. The aim of the following single center large series was to report the safety, efficacy, and functional outcome of flow diversion for aneurysms originating from small caliber vessel and compare to proximal vessels group.

METHODS

A retrospective chart review of a prospectively maintained database for subjects treated with flow diversion from 2010-2019.

RESULTS

A total of 598 aneurysms were treated during a period extending from 2010-2019 (87.8% large caliber group versus 12.20% small caliber group); 84.28% (N.=504) were females and the average age was 55.5 years. Ischemic stroke occurred at a rate of 2.99% with a non-significant difference between both groups. Delayed aneurysmal rupture and distal intraparenchymal bleed occurred at a rate of 3.70% with a non-significant difference between both groups. Complete aneurysms occlusion was seen at a rate of 75.3% with a non-significant difference between both groups. Morbidity rate occurred at a rate of 5.8% with non-significant difference between both groups. Multivariate logistic regression showed that small vessel was an independent predictor of aneurysm obliteration with a 2.6-fold-higher likelihood.

CONCLUSIONS

Flow-diverting stents are being used to treat diverse types of aneurysms and in various locations, in distal small caliber vessels where other treatment options pose a considerable risk. Small caliber group had similar complication and occlusion rates compared to proximal vessel group.

Pipeline for Distal Cerebral Circulation Aneurysms

BACKGROUND

Pipeline embolization device (PED; Medtronic, Dublin, Ireland) utilization is not limited to the treatment of giant wide-necked aneurysms. It has been expanded to handle small blisters, fusiforms, and dissecting intracranial aneurysms.

OBJECTIVE

To report the use of the PED in various off-label distal cerebral circulation (DCC) arteries with a follow-up to assess clinical outcomes.

METHODS

Between 2011 and 2016, of 437 consecutive patients, 23 patients with aneurysms located in DCCs were treated with PED. Data on patient presentation, aneurysm characteristics, procedural outcomes, postoperative course, and aneurysm occlusion were gathered. To control confounding, we used multivariable logistic regression and propensity score conditioning.

RESULTS

A total of 437 patients (mean age 52.12 years; 62 women [14.2%]) underwent treatment with PED in our institution. Twenty-three of 437 (5.2%) received a pipeline in a distal artery: 11/23 middle cerebral artery, 6/23 posterior cerebral artery, 3/23 anterior cerebral artery (A1/A2, pericallosal artery), and 3/23 posterior inferior cerebellar artery. Twenty percent of the aneurysms were treated in the past, 10% had previously ruptured, and 5.9% ruptured at presentation to our hospital. The mean aneurysm size was 9.0 ± 6 mm. The mean follow-up was 12 mo (SD = 12.5). In multivariable logistic regression, no associations were found between PED deployment in DCCs and aneurysm occlusion or thromboembolic complications. PED use in DCC was associated with a good clinical outcome. Twenty-two people of 23 (95%) had a good clinical outcome in the latest follow-up.

CONCLUSION

Treatment of DCC aneurysms with PED is technically challenging mainly because of the small caliber and tortuosity of the parent arteries. The results of this study further support the safety of flow diverters in the treatment of various distal aneurysms.

Low Yield of Cerebral Angiography in Adequately Occluded Aneurysms After Flow Diversion

BACKGROUND

Flow diversion has emerged as a highly effective treatment for intracranial aneurysms.

OBJECTIVE

To assess the yield of further angiographic follow-up in aneurysms that have achieved adequate occlusion after treatment with the Pipeline Embolization Device (PED; Medtronic Inc, Dublin, Ireland).

METHODS

This is a single-institution, retrospective study. Inclusion criteria were as follows: (1) patients with 1 or more aneurysms treated with PED, (2) available short-term (<12 mo) follow-up digital subtraction angiography (DSA), (3) complete (100%) or near-complete (>95%) occlusion on short-term follow-up DSA, and (4) available further angiographic follow-up (DSA, Magnetic Resonance Angiography (MRA), or Computed Tomography Angiography (CTA)).

RESULTS

A total of 146 patients were identified. Aneurysm size was 8.4 ± 5.1 mm on average. Mean angiographic follow-up time was 29.7 ± 12.2 mo. On short-term follow-up DSA images, 132 (90.4%) had complete aneurysm occlusion and 14 (9.6%) had near-complete occlusion. Four patients (3%) had further DSA follow-up alone, 30 patients (21%) had further DSA and MRA/CTA follow-up, and 112 patients (76%) had further MRA/CTA follow-up alone. On further angiographic follow-up (DSA, MRA, and/or CTA), no patient had a decrease in the degree of aneurysm occlusion (recurrence) or required retreatment. Of the 14 patients with near-complete occlusion on initial DSA images, 7 patients (50%) progressed to complete aneurysm occlusion on further angiographic follow-up.

CONCLUSION

This study did not find any diagnostic yield in repeating cerebral angiography in adequately occluded aneurysms with the PED. We do not recommend repeat angiographic follow-up once aneurysms have achieved complete occlusion with the PED unless clinically warranted.

Off-label uses of the Pipeline embolization device: a review of the literature

The Pipeline embolization device (PED) is the most widely used flow diverter in endovascular neurosurgery. In 2011, the device received FDA approval for the treatment of large and giant aneurysms in the internal carotid artery extending from the petrous to the superior hypophyseal segments. However, as popularity of the device grew and neurosurgeons gained more experience, its use has extended to several other indications. Some of these off-label uses include previously treated aneurysms, acutely ruptured aneurysms, small aneurysms, distal circulation aneurysms, posterior circulation aneurysms, fusiform aneurysms, dissecting aneurysms, pseudoaneurysms, and even carotid-cavernous fistulas. The authors present a literature review of the safety and efficacy of the PED in these off-label uses.