Incidence of delayed ipsilateral intraparenchymal hemorrhage after stent-assisted coiling of intracranial aneurysms in a high-volume single center

Nomogram for predicting delayed intraparenchymal hemorrhage after pipeline embolization device treatment in patients with intracranial aneurysms: a multicenter, retrospective model development and validation study

BACKGROUND

Delayed intraparenchymal hemorrhage (DIPH) is a severe complication after pipeline embolization device (PED) deployment for intracranial aneurysms (IAs). However, predictive models are lacking. This study aims to develop and validate a new nomogram to predict DIPH risk in IA patients.

METHODS

This retrospective study included 959 IA patients treated with PEDs at three institutions between October 2018 and June 2024. Patients were categorized into a training cohort (n=685) and a validation cohort (n=274). Predictors were identified using the least absolute shrinkage and selection operator and multivariable regression analyses. A nomogram was developed based on these predictors. The area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis (DCA) were utilized to assess the predictive accuracy and clinical value of the nomograms.

RESULTS

The incidence of DIPH was 2.3% in the training cohort. Multivariate logistic regression analysis demonstrated that age (odds ratio [OR] per 10 years, 2.063, P=0.005), maximum diameter (OR, 1.099, P=0.004), adenosine diphosphate-induced maximal platelet aggregation (OR, 0.896, P<0.001), and overlapping devices (OR, 7.226, P=0.007) were independent risk factors for DIPH. A nomogram was developed based on these four predictors. The AUCs of the nomogram in the training and validation cohorts were 0.875 (95% CI, 0.762 to 0.988) and 0.886 (95% CI, 0.757 to 1.000), respectively. The calibration curve and DCA analyses confirmed the utility and clinical applicability of the nomogram.

CONCLUSION

A simple to use nomogram for the individualized prediction of DIPH after PED treatment in patients with IAs was constructed, which may facilitate early identification of high-risk patients and the development of advanced treatment strategies.

Predictors of poor functional outcome after endovascular treatment in patients with poor-grade aneurysmal subarachnoid hemorrhage

OBJECTIVE

Endovascular treatment (EVT) is considered an effective treatment for patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH). Although the prognosis of these patients seems to have improved in recent years, it is generally still considered poor. We analyzed our data to determine potential predictors of poor prognosis in these patients.

METHODS

We retrospectively analyzed data from patients with poor-grade aSAH who underwent EVT at our institution between November 2018 and June 2023. The data included patient baseline clinical characteristics, treatment modalities, imaging features, postoperative complications, and functional neurological outcomes. At six months, outcomes were assessed using the modified Rankin scale (mRS) and dichotomized into good (mRS 0-2) and poor (mRS 3-6) groups. Multivariate analysis was performed to identify predictors of outcome, and the discriminative ability of the model was assessed using the area under the receiver operating characteristic curve (ROC).

RESULTS

The study included 117 poor-grade aSAH patients who underwent EVT. Fifty-eight (49.6 %) patients had poor outcomes. Univariate analysis suggested that older age (p = 0.003), higher Hunt-Hess (H-H) grade (15.3 % vs. 46.6 %, p < 0.001), posterior circulation aneurysms (15.3 % vs.31.0 %, p = 0.050)hydrocephalus (39.0 % vs. 63.8 %, p = 0.010), intraventricular hematoma (IVH) (69.5 % vs. 87.9 %, p = 0.023), ventricular casting (8.5 % vs. 43.1 %, p < 0.001), and external ventricular drainage (EVD) (44.1 % vs. 77.6 %, p < 0.001) were associated with poor outcomes. Multivariate analysis revealed that older age, higher H-H grade, and ventricular casting were predictors of poor outcomes with good discriminative ability (ROC=0.81, 95 % CI 0.73-0.89; p < 0.001).

CONCLUSIONS

Older age, higher H-H grade, and ventricular casting are associated with poor outcomes in patients with poor-grade aSAH. In this study, 50.4 % of patients achieved good outcomes, suggesting that early individualized treatment should be aggressively pursued for poor-grade aSAH patients to avoid rebleeding from ruptured aneurysms and potentially poor outcomes.

Clinically Silent Microinfarct Incidence and Risk Factors After Treatment of Unruptured Intracranial Aneurysms with Hydrophilic Polymer-Coated Flow Diverters

PURPOSE

Although flow diverters (FDs) revolutionized the treatment of unruptured intracranial aneurysms (UIAs), clinically silent microinfarcts (SMs) are consistently detected in postprocedural diffusion-weighted imaging (DWI), and their clinical consequences remain unknown. This study examined the incidence of, and factors associated with, SM development after the use of two surface-modified FDs: the p48MW-HPC and p64MW-HPC.

METHODS

A non-concurrent cohort study was conducted in 404 consecutive patients with UIAs treated with these two FDs between January 2020 and July 2023. The primary endpoint was the number of asymptomatic DWI lesions within 72 h after the procedure.

RESULTS

SMs were detected in 58.2% of the cases, and ≥ 20 lesions were identified in 7.2% of cases. Multivariate analysis revealed that the use of two specific types of microcatheters-Prowler Select Plus (P < 0.001; IRR, 3.2) and RapidTransit (P = 0.001; IRR, 2.2)-and difficulty in microcatheter navigation to the target vessel (P = 0.039; IRR, 1.8) were significantly associated with greater numbers of lesions. After exclusion of outlier cases, these devices remained associated with a significant 2‑ to 3‑fold increase in SMs. Diabetes was associated with fewer SMs (P = 0.024; IRR, 0.5), although this association disappeared after exclusion of outlier cases.

CONCLUSION

The postprocedural incidence of SMs associated with hydrophilic polymer-coated FDs was similar to that previously reported. Interestingly, the main factor contributing to this phenomenon was the use of certain microcatheters. Careful device selection is crucial, and further research is needed to improve the safety of neurovascular interventions.

Different antiplatelet regimens for stenting versus coiling for acutely-ruptured cerebral aneurysms

To investigate the safety, efficacy and risk factors for complications of stenting with optional coiling versus coiling alone for acutely ruptured cerebral aneurysms (ARCAs) using different antiplatelet schemes, 2021 patients were prospectively enrolled into the stenting group (n = 967) and the coiling group (n = 1054). Four different antiplatelet regimens were used. The clinical and treatment data were analyzed and compared. In the stenting group, the common antiplatelet regimen was applied in 259 patients (26.8%), loading regimen in 210 (21.7%), intravenous tirofiban regimen in 240 (24.8%), and premedication free regimen in 258 (26.7%). The aneurysm occlusion degrees in the coiling vs. stenting group were not significantly (P > 0.05) different after treatment. Complications occurred in 168 (15.94%) and 171 (17.68%) patients in the coiling and the stenting group, respectively. Fifteen (1.55%) patients experienced stent-related ischemic complications. The only significant (P < 0.05) independent protective factor for complete occlusion was stent-assisted coiling in the stenting group but aneurysm daughter sac in the coiling group. Significant (P < 0.05) independent risk factors for poor mRS (3-6) were posterior circulation aneurysms and neurological bleeding complications in the stenting group and neurological complications in the coiling group. In the stenting group, the only independent risk factor was parent artery stenosis for neurological complications, Raymond grade III for neurological ischemic complications, and the ice cream technique for total complications in the stenting group. In conclusion, different antiplatelet schemes can be safely and efficiently used for intracranial stenting with optional coiling as compared with coiling alone for ARCAs.

Three-dimensional reconstruction imaging by C-arm computed tomography accurately visualizes in-stent neointimal formation in patients with stent-assisted coil embolization

Background

Stent apposition to the vessel wall and in-stent neointimal formation after stent-assisted coil embolization for intracranial aneurysm are important factors associated with postoperative thromboembolic complications. No assessment methods have been established to depict 3-dimensional (3D) all-round in-stent neointimal formation.

Objective

To demonstrate the superiority of Dyna-3D imaging assessment as a modality for all-round ISNF in comparison with conventional two-dimensional digital subtraction angiography (2D-DSA).

Methods

Consecutive patients who underwent braided stent-assisted coil embolization for unruptured aneurysm between November 2016 and September 2021 were enrolled. Radiological assessments for stent apposition to the parent vessel after stent deployment and in-stent neointimal formation after 3 months were obtained. Dyna-3D was reconstructed by overlapping a plain image showing stent struts with a rotational DSA image showing the vessel lumen. Reconstructed Dyna-3D images can be rotated to any angle on the screen to evaluate to stent apposition around the vessel and in-stent neointimal formation in 3D, for comparison with 2D-DSA evaluations.

Results

Among the 73 patients enrolled, 70 patients (96%) showed complete stent wall apposition on Dyna-3D. Higher intra-rater agreement was confirmed on assessment of in-stent neointimal formation with Dyna-3D (Cohen's κ = 0.811) than with conventional 2D-DSA (Cohen's κ = 0.517). in-stent neointimal formation could not be confirmed on conventional imaging in 9 cases (16%) and on Dyna-3D in 2 cases (3%). The number of in-stent neointimal formations rated as stent wire completely outside the endothelial line was significantly higher with Dyna-3D than with 2D-DSA (p = 0.0001).

Conclusion

All-round 3D evaluation by Dyna-3D imaging appears useful for confirming in-stent neointimal formation after braided stent deployment in patients after stent-assisted coil embolization.

Endovascular Treatment of Posterior Circulation Saccular Aneurysms With the p64 Flow Modulation Device: Mid-and Long-Term Results in 54 Aneurysms From a Single Center

Objective: Flow diverter (FD) stents have become one of the most common tools for treating intracranial aneurysms; however, their role in treating posterior circulation aneurysms is still discussed with controversy. In this study, we evaluated the safety and effectiveness of p64 FD for the treatment of saccular, unruptured aneurysms in the posterior circulation over a long-term follow-up period in a single center. Methods: From our prospectively maintained database, we retrospectively identified patients who underwent treatment of an intracranial saccular aneurysm arising from the posterior circulation with ≥1 p64 FD implanted or attempted between October 2012 and December 2019. Aneurysms could have been treated with prior or concomitant saccular treatment (e.g., coiling, intra-aneurysmal flow diversion). Aneurysms with parent vessel implants other than p64, fusiform aneurysms, and dissections were excluded. Peri- and postprocedural complications, clinical outcome, and clinical and angiographic follow-up results were evaluated. Results: In total, 54 patients (45 female, 9 male; mean age 55.1 years) with 54 intracranial aneurysms met the inclusion criteria. In 51 cases (94.4%), one p64 was implanted; in 2 cases (3.7 %), two p64s were implanted; in one case, deployment of the p64 was not feasible. Procedural complications occurred in 3.7% and postprocedural complications in 9.3 %, respectively. Hemorrhagic complications occurred in 2/54 patients (3.7%), thereof one fatal parenchymal hemorrhage. Ischemic complications were observed in 5/54 patients (9.3%). Early, mid-term, and long-term angiographic follow-up examinations showed complete or near-complete aneurysm occlusion, defined according to the O'Kelly -Marotta (OKM) scale as OKM C + D in 56, 75.6, and 82.9 %, respectively. Asymptomatic side vessel occlusions occurred in 3.8%, each during the first follow-up. Conclusions: The implantation of a p64 FD is a safe and effective device for endovascular treatment of posterior circulation saccular aneurysms with a high success rate and low morbi-mortality.

Active management of the target P2Y12 reaction unit range in patients undergoing stent-assisted coil embolization for unruptured cerebral aneurysms

BACKGROUND

Platelet function tests have been increasingly adopted to measure patient responses to antiplatelet drugs, and to predict complications. However, no established optimal antiplatelet management for stent-assisted coil embolization (SAC) have been established. The purpose of the present study was to investigate the efficacy and feasibility of clopidogrel dose adjustment for active target P2Y12 reaction unit (PRU).

METHODS

A total of 202 consecutive patients undergoing SAC to treat unruptured intracranial aneurysms were prospectively recruited. All patients were given two antiplatelet agents starting 7 days prior to the procedure, and platelet function was measured with the VerifyNow test. Clopidogrel hyper-responsive patients received reduced dosing according to the values of follow-up PRUs before and 7, 14, 30, and 90 days after the procedure. Patients were divided into three groups according to clopidogrel responsiveness before treatment, and clinical outcomes and time in target PRU ranges (TTR) were analyzed.

RESULTS

No delayed ischemic or hemorrhagic events occurred that were associated with out-of-range PRU. PRU values in the hypo-responsive and hyper-responsive groups significantly improved 7 days after treatment with active target PRU management (p=0.05,<0.001, respectively). PRU values were controlled within the target PRU range with drug adjustment (p=0.034), and the time in TTR for all patients was 97% (4.8%-100%), which showed the feasibility of optimal control of PRU values with the protocol.

CONCLUSION

Active target PRU management can achieve control of optimal PRU values and may decrease perioperative ischemic and hemorrhagic events among patients undergoing SAC.

Factors associated with the new appearance of cerebral microbleeds after endovascular treatment for unruptured intracranial aneurysms

PURPOSE

Endovascular treatment of unruptured intracranial aneurysms may increase cerebral microbleeds (CMBs) in postprocedural T2*-weighted MRIs, which may be a risk for future intracerebral hemorrhage. This study examined the characteristics of postprocedural CMBs and the factors that cause their increase.

METHODS

The patients who underwent endovascular treatment for unruptured intracranial aneurysms from April 2016 to February 2018 were retrospectively analyzed. Treatment techniques for endovascular treatment included simple coiling, balloon-assisted coiling, stent-assisted coiling, or flow diverter placement. To evaluate the increase in CMBs, a head MRI including diffusion-weighted imaging and T2*-weighted MRIs was performed on the preprocedural day; the first postprocedural day; and at 1, 3, and 6 months after the procedure.

RESULTS

Among the 101 aneurysms that were analyzed, 38 (37.6%) showed the appearance of new CMBs. In the multivariate analysis examining the causes of the CMB increases, chronic kidney disease, a higher number of preprocedural CMBs, and a higher number of diffusion-weighted imaging-positive lesions on the first postprocedural day were independent risk factors. Furthermore, a greater portion of the increased CMBs was found in cortical and subcortical lesions of the treated vascular perfusion area within 1 month after the procedure.

CONCLUSION

In endovascular treatment for unruptured intracranial aneurysms, CMBs tended to increase in patients with small vessel disease before the procedure, and it was also implicated in hemorrhagic changes after periprocedural microinfarction.

Does Systemic Lupus Erythematosus Increase the Risk of Procedure-Related Complication in Endovascular Treatment of Intracranial Aneurysm?

Cerebral aneurysms associated with systemic lupus erythematosus (SLE) are more likely to grow rapidly and rupture, compared to those found in the general population. The main underlying pathology of intracranial aneurysm and its rupture is presumed to be SLE-related intracranial vasculitis and fragility of blood vessels due to prolonged use of steroid. For these reasons, both surgical and endovascular options are challenging. On the other hand, given the possibility that SLE may predispose to growth and rupture of intracranial aneurysm, early intervention for cerebral aneurysms associated with SLE may be more necessary and beneficial than other cerebral aneurysms in the general population. Here we would like to report on the unexpected complications that occurred during or after endovascular treatment of an SLE patient with multiple aneurysms. The complications include intraprocedural rupture of unruptured aneurysm, coil stretching, contrast-induced encephalopathy, and delayed ipsilateral intraparenchymal hemorrhage after stent-assisted coiling. Our unique case highlights that the SLE patient with multiple intracranial aneurysms had a higher risk of endovascular procedure-related complications, which might be due to the increased bleeding tendency and fragility of blood vessels.

The profile of blunt traumatic infratentorial cranial bleed types

Infratentorial traumatic intracranial bleeds (ICBs) are rare and the distribution of subtypes is unknown. To characterize this distribution the National Trauma Data Bank (NTDB) 2014 was queried for adults with single type infratentorial ICB, n = 1,821: subdural hemorrhage (SDH), subarachnoid hemorrhage (SAH), epidural hemorrhage (EDH), and intraparenchymal hemorrhage (IPH). Comparisons were made between the groups with statistical significance determined using chi squared and t-tests. SDH occurred in 29% of patients, mostly in elderly on anti-coagulants (13%) after a fall (77%), 42% of them underwent craniotomy, their mortality was the lowest (4%). SAH was the most common (56%) occurring mostly from traffic related injuries (27%). Furthermore, 9% of them had a severe head injury Glasgow Coma Scale ≤8 (GCS), but had the lowest Injury Severity Score (ISS, median 8) as well as a short hospital length of stay, 5.1 ± 6.2 days. These patients were most likely to be discharged to home (64%). They had the lowest mortality (4%). EDH was the least common ICB (5%), occurred in younger patients (median age 49 years), and it had the highest percentage of associated injuries (13%). EDH patients presented with the poorest neurological status (26% GCS ≤8, ISS median 25) and were operated on more than any other ICB type (55%). EDH was the highest mortality (9%) ICB type and had a low discharge to home rate (58%). IPH was uncommon (10%). Infratentorial bleeds types have different clinical courses, and outcomes. Understanding these differences can be useful in managing these patients.

Clinical and angiographic outcomes in patients with intracranial aneurysms treated with the pipeline embolization device: intra-procedural technical difficulties, major morbidity, and neurological mortality decrease significantly with increased operator experience in device deployment and patient management

PURPOSE

Flow diversion constitutes a pivotal advancement in endovascular intracranial aneurysm treatment, but requires development of a new skill set. The aim of this study is to determine whether outcomes after treatment with the Pipeline Embolization Device improve with experience.

METHODS

We retrospectively reviewed all patients with intracranial aneurysms treated with Pipeline at two centers over a 4.5-year period. Baseline patient and aneurysm characteristics, complications, and angiographic outcomes were analyzed.

RESULTS

One hundred forty patients underwent 150 Pipeline procedures to treat 167 intracranial aneurysms during the study period, 109 women, mean age 55.4 years. One hundred twenty-six aneurysms were ICA, mean size 10.2 mm and mean neck 6.4 mm. Intra-procedural technical difficulties were higher during the first 75 procedures compared with the subsequent 75 (13.3 vs 2.7%; p = 0.03), as combined major morbidity and neurological mortality (14.7 vs 4%; p = 0.046). In multivariate regression analysis, increased operator experience with Pipeline remained an independent predictor of intra-procedural technical difficulties (p = 0.02, odds ratio (OR) 0.015, 95% CI 0.0004-0.55) and combined major morbidity and neurological mortality (p = 0.03, OR 0.16, 95% CI 0.03-0.84). At last follow-up, 123 aneurysms were completely occluded (81.5%, mean 24 months). In our cohort, age ≤ 53 years was an independent predictor of complete aneurysm occlusion at last follow-up (p = 0.001, OR 0.92, 95% CI 0.88-0.97). Five aneurysms were retreated (3.3%).

CONCLUSION

The Pipeline embolization device is an effective treatment for intracranial aneurysms. The risk of intra-procedural technical difficulties and combined major morbidity and neurological mortality decreases significantly with increased operator experience in Pipeline deployment and patient management.

Aneurysm size and the Windkessel effect: An analysis of contrast intensity in digital subtraction angiography

Large cerebral aneurysms are considered more dangerous than their smaller counterparts, with higher risk of subarachnoid hemorrhage. Understanding the hemodynamics of large aneurysms has potential to predict their response to treatment. Digital subtraction angiography images for patients with intracranial aneurysms over a seven-year period were reviewed. Unruptured solitary aneurysms of the internal carotid artery (ICA) proximal to the terminus and posterior communicating artery were included. Contrast intensity over time was analyzed at the center of the M1 segment of the middle cerebral artery distal to the aneurysm and compared to the contralateral side. Analysis included time to peak (TP)10%-100% (time needed for contrast to change from 10% intensity to 100%), washout time (WT)100%-10% (time for 100% intensity to 10%), and quartile time (QT)25%-25% (time for 25% intensity during vessel filling to 25% during emptying). Fifty patients met the inclusion criteria. Analysis over the ipsilateral M1 segment revealed a significant increase in QT25%-25% (8.5 vs 7.6 seconds, p = 0.006) compared to the contralateral side. There was a correlation between TP10%-100% and QT25%-25% with aneurysm size (Pearson's r = 0.37, p = 0.007 and r = 0.43, p = 0.001, respectively). Larger ICA aneurysms were associated with delayed contrast intensity times . A plausible mechanism is that large aneurysms act as a capacitance chamber (Windkessel effect) that slow the arrival of contrast distal to the aneurysm. This may be of significance for large aneurysms after treatment, where the loss of the Windkessel effect places the distal circulation at greater risk for hemorrhage, and warrants further study.

Changes in contrast transit times on digital subtraction angiography post-Pipeline Embolization Device deployment

It is postulated that hemodynamic changes occur in the distal vascular bed post-deployment of Pipeline Embolization Devices (PEDs). In this paper, we evaluate changes in the contrast transit times (TTs) on digital subtraction angiography (DSA) post-PED interventions. DSA films were analyzed using custom-made software for the time-density relationship at baseline and compared to post-PED deployment. All analyses were performed within the middle cerebral artery (MCA) M1 segment. Analyses included TT10%-100% (time needed for the contrast to change from 10% image intensity to 100%), TT100%-10%, and TT25%-25%. Forty-four patients were included. We found a significant decrease in TT10%-100% (2.79 to 2.24 seconds, p < 0.001) post-PED. There was a significant correlation between the percentage change in TT100%-10% and aneurysm size ( p = 0.02). There was also a significant decrease in TT25%-25% (7.07 to 6.41 seconds, p = 0.02) post-PED. Moreover, there was a significant correlation between the absolute or percentage changes in TT25%-25% and aneurysm size (rho = 0.54, p = 0.05 and rho = 0.29, p = 0.05, respectively). Statistically significant distal intracranial hemodynamic changes occur post-PED deployment. These hemodynamic changes appear to be more pronounced with large and giant aneurysms.