Low-Profile Visualized Intraluminal Support Device for Y-Stent-Assisted Coiling of Wide-Neck Intracranial Aneurysms: A Single Center Experience

BACKGROUND

The Low-Profile Visualized Intraluminal Support (LVIS) device has been frequently used as intracranial stent for treating intracranial aneurysms. However, the feasibility and efficacy of LVIS devices in Y-stent-assisted coiling (Y-SAC) have remained contentious. This study aimed to evaluate long-term angiographic and clinical outcomes of Y-SAC using LVIS devices.

METHODS

We retrospectively reviewed the clinical presentation and angiography data of patients treated with Y-SAC using LVIS stents. The vascular angle geometry between the parent and the two branch vessels, before and after stent deployment and after coiling were analyzed. Based on Raymond-Roy Occlusion Classification (RROC), aneurysm occlusion status was classified. Clinical outcomes were assessed using the modified Rankin Scale (MRS).

RESULTS

Forty patients with 40 aneurysms were included in this study. Immediate postprocedural angiograms revealed complete/near-complete occlusion (RROC 1 and 2) in 31 aneurysms (77.5%). The long-term follow-up angiographic studies were available in 32 patients revealing RROC class 1 and 2 in 93.8% of patients. Y-SAC with LVIS devices significantly decreased the angle between the bifurcation branches from 171.90 ° ± 48.0° (SD) to 130.21° ± 46.3° (SD) (p<0.0001). Periprocedural complications occurred in five patients (12.5%) including four in-stent thrombosis (10.5%). Thirty-six patients (90.0%) had favorable clinical outcomes at the final follow-up. Univariate analysis depicted that WFNS of 3-5, thick of subarachnoid hemorrhage on head CT scan, intraprocedural complications, and in-stent thrombosis were predictors of poor outcome.

CONCLUSION

Y-SAC using LVIS device for intracranial bifurcation aneurysms is a feasible and relatively safe procedure with favorable long-term angiographic and clinical outcomes.

Stent plus balloon-assisted coiling with low-profile braided stents in the treatment of complex wide-necked intracranial bifurcation aneurysms

INTRODUCTION

Wide-necked bifurcation aneurysms pose significant challenges for endovascular treatment. A recent innovation, the stent plus balloon-assisted coiling technique, combines a stent and a balloon to address these aneurysms effectively.

PURPOSE

To evaluate the safety and efficacy of the stent plus balloon-assisted coiling for the treatment of wide-necked bifurcation aneurysms.

METHODS

We conducted a retrospective review of our endovascular database to identify patients who were treated with this technique and had a satisfactory angiographic follow-up of at least 24 months. Technical success, initial clinical and angiographic outcomes, procedural complications, and follow-up results were analyzed. Angiographic and clinical outcomes were assessed using Modified Raymond-Roy Classification and Modified Rankin Scale, respectively.

RESULTS

Our study included 37 aneurysms in 36 patients (26 females) with a mean age of 56.6 years. Mean aneurysm and neck sizes were 7.3 ± 3.5 mm and 3.7 ± 1.0 mm, respectively. Technical success reached 97.2%, with an immediate occlusion rate of 65.7%. At a mean follow-up of 36.5 ± 9.7 months, final angiographic follow-up showed a 91.9% complete occlusion rate. Three aneurysms did not achieve complete occlusion; however, none required retreatment. Complications developed in 32.4% of the procedures. Mortality and morbidity rates were 5.4% and 2.7%, respectively. A good clinical outcome was observed in 91.9% of patients.

CONCLUSION

Our results showed that stent plus balloon-assisted coiling technique allows good angiographic outcomes for wide-necked bifurcation aneurysms. However, overall complication rate is high. Subgroup analysis indicated promising safety and efficacy for MCA bifurcation aneurysms, suggesting this technique could be a valuable option for select aneurysms.

Statistical Analysis of the Factors that Affect Postoperative Length of Hospital Stay after Unruptured Intracranial Aneurysm Treatment in Japan: A 20-year Nationwide Multicenter Study

Treatment strategies for unruptured intracranial aneurysms (UIAs) should be carefully considered with reference to rupture and complication rates. It is also important to minimize the length of hospital stay (LOS) and to ensure a high quality of medical care. In this study, we aim to clarify the factors that affect the LOS of patients treated for UIAs using the Inpatient Clinico-Occupational Database of the Rosai Hospital Group (ICOD-R). This was a nationwide-multicenter study based on ICOD-R data from 2000 to 2019. Patients diagnosed with UIAs who were treated with clipping or coiling were included in the study. Multivariate analysis was performed to identify the factors affecting LOS. LOS was also compared between groups classified by surgical procedure or treatment period. We identified 3294 patients on the database who underwent clipping or coiling of UIAs during the study period. Multivariate analysis revealed hospital admission during the early 2000s and the late 2010s, age, and treating institution to be significantly correlated with LOS (p < 0.05). There was a significant difference between the mean LOS of the clipping group (20.3 days) and the coiling group (9.65 days) (p < 0.001). Compared by treatment period, LOS significantly shortened over time. Our results suggest that the type of treatment, time of treatment, patient age, and the treating institution affect postoperative LOS for UIAs. Although coiling was found to lead to a lower average LOS than clipping, treatment selection should take the characteristics of each patient's aneurysm into consideration.

The impact of regular aspirin use on aneurysm recanalization rates after endovascular coiling

OBJECTIVE

Intracranial aneurysms (IAs) pose a significant health risk, often leading to subarachnoid hemorrhage and severe neurological outcomes. Endovascular coiling has been a principal treatment method, but it comes with the challenge of high recanalization rates. Aspirin has recently emerged as a potential agent to reduce these rates. In this study, the authors aimed to investigate the impact of regular aspirin use on aneurysm recanalization rates following endovascular coiling in a 10-year single-institution study.

METHODS

A retrospective analysis was conducted on a dataset of 2236 aneurysms treated by a single neurosurgeon over a period of 10 years. The primary outcome measure was aneurysm recanalization, defined by a change in the Raymond-Roy Occlusion Classification of at least one grade.

RESULTS

A total of 525 aneurysms were coiled, 109 of which involved patients who reported regular use of aspirin. The recanalization rate was significantly lower in the aspirin group (9.2%) compared with the control group (23.6%) (OR 0.33, 95% CI 0.15-0.66; p = 0.001). On analysis of the specific mechanisms of recanalization, aneurysm sac growth was less frequent in the aspirin group (5.5%) compared with the control group (18%) (OR 0.265, 95% CI 0.09-0.63; p = 0.002). Additionally, patients in the control group had a higher retreatment rate (18%) than patients in the aspirin group (5.5%) (OR 0.265, 95% CI 0.09-0.63; p = 0.002).

CONCLUSIONS

Regular use of aspirin appears to be associated with reduced rates of aneurysm recanalization after endovascular coiling. However, caution is advised in interpretation of these results given the retrospective nature of this study. Further randomized controlled trials are needed to confirm these findings.

Flow diverters versus stent-assisted coiling in unruptured intracranial vertebral artery dissecting aneurysms

OBJECTIVE

Flow diverters (FDs) have been used in unruptured intracranial vertebral artery dissecting aneurysms (IVADAs) with seemingly more favorable outcomes compared with stent-assisted coiling (SAC). However, the benefits of FDs over SAC in unruptured IVADAs need further evaluation.

METHODS

This was a propensity score-matched, retrospective cohort study. Consecutive patients with unruptured IVADAs treated with FDs or SAC at the authors' hospital between January 2016 and December 2020 were reviewed. Propensity score matching at 1:1 was based on age, significant stenosis adjacent to aneurysmal dilatation, maximum diameter, and posterior inferior cerebellar artery involvement. Periprocedural cerebrovascular complications and angiographic and clinical outcomes were compared between the two matched groups.

RESULTS

A total of 124 unruptured IVADAs in 123 patients (median age 53 [interquartile range 47-59] years; 101 men) were included. The FD and SAC groups included 65 and 59 IVADAs, respectively. Propensity score matching resulted in 47 matched pairs. The rates of immediate complete occlusion were significantly lower in the matched FD group than in the matched SAC group (6.4% vs 68.1%, p < 0.001). The rates of periprocedural cerebrovascular complications were comparable between the two matched groups (6.4% vs 6.4%, p > 0.99). At last follow-up, the rates of complete occlusion (89.4% vs 80.9%, p = 0.39) and favorable clinical outcomes (100.0% vs 97.9%, p > 0.99) were comparable, whereas the rate of recanalization was significantly lower in the matched FD group than in the matched SAC group (0.0% vs 12.8%, p = 0.03). Although the difference between the rates of in-stent stenosis was not statistically significant (17.0% vs 6.4%, p = 0.18), the difference in the effect measures was considerable.

CONCLUSIONS

In unruptured IVADAs and compared with SAC, FDs provide comparable rates of periprocedural cerebrovascular complications, favorable clinical outcomes, and follow-up complete occlusion, lower rates of immediate complete occlusion and follow-up recanalization, and likely higher rates of in-stent stenosis.

Endovascular outcomes for anterior choroidal artery aneurysms: systematic review and meta-analysis

BACKGROUND

Anterior choroidal artery (AchoA) aneurysms are relatively rare compared to other types of aneurysms. However, the occurrence of transient or permanent occlusion of the choroidal artery during endovascular or surgical treatment is an uncommon but potentially serious complication. In this study, we aim to investigate the safety and efficacy profile of endovascular treatment (EVT) for AchoA aneurysms.

METHODS

The primary outcome of interest was angiographic and clinical outcomes. Secondary outcome variables transient and permanent ischemic complications, symptomatic choroidal artery occlusion and retreatment rates. A random-effects model was used to calculate prevalence rates and their corresponding 95 % confidence intervals (CI), and subgroup analyses were performed to assess the complication rates for Type 1(arterial type, directly arising from ICA) and Type 2(neck type, arising from AchoA branch)) AchoA aneurysms, ruptured vs non-ruptured and for flow diverter (FD) treatment versus coiling.

RESULTS

Our study included 10 studies with 416 patients with 430 AchoA aneurysms. The overall good clinical outcome rate (mRS score 0-2) is 94.5 % with a retreatment rate of 2.0 %. A subgroup analysis showed no statistical difference between coiling(75.3 %) and flow diverter(80.9 %) treatment in terms of complete occlusion(p-value:0.62). Overall permanent complication rate is 1.4 % (p-value:0.54) and transient ischemic complications rate is 4.2 %(p-value:0.61). Symptomatic choroidal artery occlusion rate is 0.8 %(p-value:0.51)Type 2 AchoA aneurysms had a significantly higher complication rate of 9.8 % (p-value<0.05) compared to Type 1 aneurysms. Unruptured aneurysms have significantly better clinical outcomes than ruptured aneurysms(OR: 0.11; [0.02;0.5], p-value:<0.05) CONCLUSION: Endovascular treatment of AchoA aneurysms demonstrated positive clinical results, with low rates of retreatment and complications. Coiling and flow diverters proved similar outcomes in achieving aneurysm occlusion. Ruptured aneurysms have lower good clinical outcomes comparing to unruptured aneurysms. Type 2 AchoA aneurysms had a higher risk of complications compared to Type 1.

Treatment and outcome analysis of patients with ruptured distal anterior cerebral artery aneurysms: a multicenter real-world study

Objective

To reveal the safety and efficacy of clipping and coiling in patients with ruptured distal anterior cerebral artery aneurysms (DACAA) and to calculate the risk factors affecting the two-year survival rate in follow-up patients.

Methods

A retrospective study was conducted on the data of 140 patients (21 were lost to follow-up) with DACAA rupture who were treated by neurosurgery at 12 medical centers over a 2-year period, from January 2017 to December 2020. Univariate analysis was used to examine factors contributing to poor patient prognosis and to compare the prognosis of coiling and clipping treatments. Survival analysis was employed to compare survival rates between coiling and clipping, and risk factors affecting patient survival were analyzed using multivariate Cox regression analysis.

Results

Out of 140 patients with ruptured DACAA, 80 (57.1%) were male, and 60 (42.9%) were female. A total of 111 (79.3%) patients were classified under Hunt-Hess scale grades I-III, while 95 (67.9%) were graded I-III according to the WFNs classification. Among them, 63 (45%) were treated with clipping, and 77 (55%) underwent coiling. Within 2 years of discharge from the hospital, 31 (59.6%) patients who underwent clipping and 54 (80.6%) who underwent coiling had a good prognosis. Multivariate Cox regression analysis revealed that only WFNs classification (I-III) was a protective factor influencing the 2-year survival of patients with ruptured DACAA.

Conclusion

In the reality of medical practice, neurosurgeons are more likely to choose clipping as the treatment for cases with WFNs classification than or equal to III. There was no difference between clipping and coiling in the two-year prognosis at discharge. High priority should be given to DACAA cases with WFNs grading (I-III), as better outcomes can be achieved. The sample size will continue to be enlarged in the future to obtain more accurate findings. Abstracts for reviews, technical notes, and historical vignettes do not need to be separated into sections. They should begin with a clear statement of the paper's purpose followed by appropriate details that support the authors' conclusion(s).

Snare, stent retriever, and aspiration for a prematurely detached coil during treatment of a reruptured anterior communicating artery aneurysm

Advanced salvage techniques are an essential tool in the armamentarium of any experienced endovascular surgeon. In this video, we show a patient presenting with rerupture of an anterior communicating artery (ACoA) aneurysm that had been treated with balloon-assisted coiling several months earlier in a ruptured setting. Premature coil detachment occurred during an attempt to coil a new bleb that the aneurysm had developed, and a sequence of salvage maneuvers was performed. An initial attempt to implant that coil failed, and retrieval with a snare unfortunately caused coil fragmentation and occlusion of the anterior cerebral artery (ACA). Further salvage maneuvers required inducing flow-arrest with a balloon-guide catheter, use of a stent-retriever to recanalize the ACA A2 segment, and aspiration to capture a small fragment of coil that was seen at the tip of the balloon guide catheter.

Clipping versus coiling: A critical re-examination of a decades old controversy

BACKGROUND

Two major studies, The International Subarachnoid Aneurysm Trial and the Barrow Ruptured Aneurysm Trial, compare the long-term outcomes of clipping and coiling. Although these demonstrated coiling's initial benefits, rebleeding and retreatment rates as well as converging patient outcomes sparked controversy regarding its durability. This article will critically examine the available evidence for and against clipping and coiling of intracranial aneurysms. Critics of endovascular treatment state that the initial benefit seen with endovascular coiling decreases over the duration of follow-up and eventually functional outcomes of both treatment modalities are similar. Combined with the increased rate of retreatment and rebleeding, these trials reveal that coiling is not as durable and not as effective as a long-term treatment compared to clipping. Also, due to the cost of devices following endovascular treatment and prolonged hospitalization following clipping, the financial burden has been considered controversial.

SUMMARY/KEY MESSAGES

Short-term outcomes reveal better morbidity and mortality outcomes following coiling. Despite the higher rates of retreatment and rebleeding with coiling, there was no significant change in functional outcomes following retreatment. Furthermore, examining more recent trials reveals a decreased rate of recurrence and rebleeding with improved technology and expertise. Functional outcomes deteriorate for both cohorts over time while recent results revealed improved long-term cognitive outcomes and levels of health-related quality of life after coiling in comparison to clipping. The expense of longer hospital stays following clipping must be balanced against the expense of endovascular devices in coiling.

Technical nuances of flow-diverting stent-assisted coiling of a ruptured carotid wall aneurysm

The management of ruptured, large and giant wide-necked aneurysms of the anterior circulation is challenging. Treatment options include balloon-assisted coiling versus flow-diverter-assisted coiling. In this technical video, https://drive.google.com/file/d/1EtyrJv3e5Z0XM2pYBNNBHVUdYwavlTFh/view?usp = sharing we demonstrate a case of a right-sided paraclinoid aneurysm in a young man who presented with post-coital sudden-onset headache. The computed tomography scan showed a Fisher grade IV subarachnoid hemorrhage. An external ventricular drain was placed, and the patient was intubated for prompt treatment. Balloon-assisted coiling of the aneurysm was attempted but abandoned because the balloon failed to provide adequate coverage of the aneurysm neck. A loading dose of aspirin and ticagrelor (Brilinta, Astra Zeneca, Cambridge, United Kingdom) was administered, and Pipeline embolization device (Medtronic, Dublin, Ireland)-assisted coiling was then performed for adequate occlusion of the aneurysm sac. The 6-month follow-up angiogram showed complete obliteration of the aneurysm. The technical video succinctly demonstrates the technical nuances of the procedure.

Evaluation of a novel polymer coil for endovascular occlusion of intracranial aneurysms in a rabbit model

BACKGROUND AND PURPOSE

The results of the preclinical study of a novel polymer coil in treatment of elastase induced aneurysms will be presented in this paper.

MATERIAL AND METHODS

We induced 16 aneurysms in 16 New Zealand white rabbits at the origin of the right common carotid artery at the brachiocephalic trunk. Newly developed polymer coils in both groups for six aneurysms each and platinum coils for two aneurysms each were used. Control angiographies followed in both groups immediately after coiling as well as in the first eight animals 30 days after intervention (30 days group) and in the other eight animals 90 days after (90 days group). An explanation and histological evaluation of the treated aneurysms followed.

RESULTS

The 12 animals in which the aneurysms were treated with polymer coils showed a complete occlusion (grade IV) in only 6 out of 12 aneurysms (50%), an almost complete occlusion (grade III) in 5 out of 12 (42%) and an incomplete occlusion in the treatment of one aneurysm (8%). Histologically, we observed a significantly more pronounced inflammatory response and neoangiogenesis in aneurysms treated with polymer coils only in the 30 days group.

CONCLUSION

Most difficulties and concerns with the polymer coils were related to the flexibility and detachment behaviour. Therefore, and due to the technical challenges of delivery, the novel polymer coil cannot be considered an alternative to the current platinum coils.

Closure of Post-thrombotic Iliac Arteriovenous Fistulas by Iliac Vein Recanalization

PURPOSE

The purpose of this study was to report the closure of iliac arteriovenous fistulas associated with a post-thrombotic iliac vein occlusion by iliac venous stent recanalization.

CASE REPORT

An 80-year-old woman presented with a worsening painful swelling of her left leg after an iliofemoral deep vein thrombosis 6 months ago. Duplex ultrasound and magnetic resonance venography revealed a post-thrombotic obstruction of her iliac veins as well as several arteriovenous fistulas between branches of her left external and internal iliac arteries and adjacent diseased venous segments. In a first attempt, coil embolization did not sustainably close these iliac arteriovenous fistulas. Direct stent recanalization of the chronically diseased iliofemoral venous segment, however, resulted in an immediate closure of arteriovenous shunt flow and subsequent improvement of clinical symptoms. Six months after iliac vein stent recanalization, still no fistulas could be detected any more, venous stents were fully patent, and the patient was free of symptoms.

CONCLUSION

Post-thrombotic iliofemoral obstructions might be associated with the development of arteriovenous fistulas. Direct stent recanalization of the chronically occluded veins results in closure of related arteriovenous fistulas.

CLINICAL IMPACT

This case suggests that the combined occurrence of post-thrombotic venous obstructions with arteriovenous fistulas, which are related to aforementioned venous lesions, should be evaluated for primary venous stent recanalization rather than fistula embolization.

High signal intensity of the intraaneurysmal sac on T1 CUBE imaging as a predictor of aneurysm stability after coil embolization

OBJECTIVE

Histopathological studies of aneurysms after coil embolization showed that thrombus formation during the first month after endovascular treatment (EVT) played an important role in the healing process. The authors hypothesized that dedicated T1-weighted imaging may be used to predict stable aneurysms by visualizing the thrombus status within coil-treated aneurysms. Therefore, this study investigated the relationship between the signal intensity (SI) of the intraaneurysmal sac after coil embolization and aneurysm stability.

METHODS

The study population included 82 patients with 86 aneurysms who underwent T1-weighted 3D black-blood fast spin-echo (T1 CUBE) imaging within 1 month after coil embolization between 2019 and 2022. The relative SI of a coil-treated aneurysm (RSIcoiled) was calculated as follows: the mean SI of the intraaneurysmal sac/the mean SI of the genu of the corpus callosum. Aneurysms with enlarged remnants on MR angiography (MRA) within 6 months after EVT were defined as recurrence, while a decrease of intraaneurysmal flow on MRA was defined as improved embolization status. Stable aneurysms were defined as improvement or no change in embolization status 6 months after coil embolization. The volume embolization ratio (VER) was calculated as the ratio of the packed coil volume to the aneurysm volume. Differences between stable and recurrent aneurysms were examined. All aneurysms were divided into high and low RSIcoiled groups based on the cutoff value of RSIcoiled, and differences between the two groups were also evaluated.

RESULTS

Recurrence was confirmed for 26 of 86 aneurysms. A univariable analysis showed that small aneurysms, high VER, and high RSIcoiled were associated with aneurysm stability. In the receiver operating characteristic curve analysis, the optimal cutoff value for RSIcoiled to differentiate stable from recurrent aneurysms was 0.54. The cutoff value for RSIcoiled was selected as 0.50 (sensitivity 0.77, specificity 0.70) because it was half the value of the SI of the corpus callosum and close to the optimal cutoff value. In a multivariable analysis, RSIcoiled > 0.50 (OR 8.1, 95% CI 2.5-27) remained a significant factor for aneurysm stability. The high RSIcoiled group showed a higher rate of an improved embolization status (26% vs 6.1%, p = 0.022) and stable aneurysms (85% vs 15%, p = 0.0002).

CONCLUSIONS

RSIcoiled was associated with postcoiling aneurysm stability. High RSIcoiled might imply intraaneurysmal thrombus formation associated with the healing process of coil-treated aneurysms.

Force Generation in the Coiling Tendrils of Passiflora caerulea

Tendrils of climbing plants coil along their length, thus forming a striking helical spring and generating tensional forces. It is found that, for tendrils of the passion flower Passiflora caerulea, the generated force lies in the range of 6-140 mN, which is sufficient to lash the plant tightly to its substrate. Further, it is revealed that the generated force strongly correlates with the water status of the plant. Based on a combination of in situ force measurements with anatomical investigations and dehydration-rehydration experiments on both entire tendril segments and isolated lignified tissues, a two-phasic mechanism for spring formation is proposed. First, during the free coiling phase, the center of the tendril begins to lignify unilaterally. At this stage, both the generated tension and the stability of the form of the spring still depend on turgor pressure. The unilateral contraction of a bilayer as being the possible driving force for the tendril coiling motion is discussed. Second, in a stabilization phase, the entire center of the coiled tendril lignifies, stiffening the spring and securing its function irrespective of its hydration status.

Aneurysm treatment within 6 h versus 6-24 h after rupture in patients with subarachnoid hemorrhage

BACKGROUND

The risk of rebleeding after aneurysmal subarachnoid hemorrhage (aSAH) is the highest during the initial hours after rupture. Emergency aneurysm treatment may decrease this risk, but is a logistic challenge and economic burden. We aimed to investigate whether aneurysm treatment <6 h after rupture is associated with a decreased risk of poor functional outcome compared to aneurysm treatment 6-24 h after rupture.

METHODS

We used data of patients included in the ULTRA trial (NCT02684812). All patients in ULTRA were admitted within 24 h after aneurysm rupture. For the current study, we excluded patients in whom the aneurysm was not treated <24 h after rupture. We calculated crude and adjusted risk ratios (aRR) with 95% confidence intervals using Poisson regression analyses for poor functional outcome (death or dependency, assessed by the modified Rankin Scale) after aneurysm treatment <6 h versus 6-24 h after rupture. Adjustments were made for age, sex, clinical condition on admission (WFNS scale), amount of extravasated blood (Fisher score), aneurysm location, tranexamic acid treatment, and aneurysm treatment modality.

RESULTS

We included 497 patients. Poor outcome occurred in 63/110 (57%) patients treated within 6 h compared to 145/387 (37%) patients treated 6-24 h after rupture (crude RR: 1.53, 95% CI: 1.24-1.88; adjusted RR: 1.36, 95% CI: 1.11-1.66).

CONCLUSION

Aneurysm treatment <6 h is not associated with better functional outcome than aneurysm treatment 6-24 h after rupture. Our results do not support a strategy aiming to treat every patient with a ruptured aneurysm <6 h after rupture.

PCI for Flush Occluded Right Coronary Artery: Challenges and Techniques for Success

A 74-year-old man with prior coronary artery bypass surgery had a failing vein graft to the right coronary artery (RCA). He underwent retrograde chronic total occlusion recanalization of an ostial flush-occluded RCA facilitated by retrograde angioplasty at the aorto-ostial junction after failed retrograde electrocautery. The graft was then sacrificed. (Level of Difficulty: Advanced.).

Management of Enterocutaneous Fistula in Crohn's Disease by Embolization With Glue Injection and Coiling: A Case Report

There is one reported case of a pancreatoduodenal fistula that was managed using combined coil embolization and fibrin glue after the failure of other methods. Herein, we document this case to highlight the value of coil embolization and fibrin glue as surgical alternatives for fistula treatment. We present a case of a 39-year-old female patient who has a known case of Crohn's disease (CD) and presented with an enterocutaneous fistula (ECF) after her most recent surgery. With the failure of conservative approaches and as she refused any surgical interventions, fibrin glue injection and coiling were used. As a conclusion, embolization may work well as a surgical management alternative due to its simplicity.

Germinating seedlings and mature shoots of Cuscuta campestris respond differently to light stimuli during parasitism but not during circumnutation

Seedlings of the parasitic plant genus Cuscuta (dodder) locate hosts by circumnutation, coil around the host near soil level and form a haustorium, establishing a primary parasitism beneath the canopy. Mature shoots elongating from the parasitic region parasitize other hosts on the upper surfaces of their canopy. Although parasitism by dodder is stimulated by blue and far-red light, and inhibited by red light, the responses to light signals during the developmental stages are not comprehensively understood. Therefore, we compared the effects of different types of light on both circumnutation and parasitism by germinating seedlings and mature shoots of Cuscuta campestris. Seedlings established parasitism under blue and far-red light, but not under red light, as has been reported repeatedly. By contrast, mature shoots exhibited coiling around the host and haustoria formation even under a red light as well as under blue and far-red light. These findings indicate that C. campestris modified its response to red light during the transition from young seedlings to mature shoots, facilitating parasitism. Light quality did not affect the circumnutation of either seedlings or mature shoots, indicating that circumnutation and the coiling movement that leads to parasitism were regulated by different environmental signals.

Development of technical skills in simulated cerebral aneurysm coiling

Endovascular surgical procedures require visual-spatial coordination in workspaces with restricted motions and temporally limited imaging. The development of the skills needed for these procedures can be facilitated by 3D simulator-based training. Cerebral angiography (CA) has lagged behind in this training approach due to the lack of validated, realistic training models, relying strictly on clinical case exposure frequency ("number of hours logged") as a means of assessing proficiency. The ANGIO Mentor visual-haptic simulator is regarded as an effective training tool, however, this simulator has not been tested thoroughly in its ability to train interventional skills. In particular, the details of the aneurysm coiling process during simulation-based training have not been assessed. In this study, 12 novice medical students were given simulation-based diagnostic CA training until a procedural plateau in performance, established in our previous work. Subsequently, they were trained using video tutorials and written instructions to identify, measure and intervene with cerebral aneurysms using endovascular coils. Over the span of 6 sessions, participants were assessed on their procedural task time, coiling quantity and quality, and perforation rates. Prior to commencing the study, participant spatial ability was assessed using a mental rotation test (MRT) and used as a comparative baseline for the performance analysis. We found that all individuals were able to perform the procedure faster after 6 sessions, reducing their average time from 42 to 24 minutes. Coil success rate improved over from 82% to 88% and coil packing rate remained consistent at 30% throughout testing. High perforation rate seen at the start of the study showed a trend of decreasing over the latter sessions, however, over half of aneurysms were still being perforated by the novice participants. No change in aneurysm coiling quality was found, with a slight decrease in number of parent artery coil protrusions. High MRT individuals were better able to establish necessary tools prior to coiling, however, no other MRT-specific changes were seen. This work identifies the utility of simulation-based CA training in identifying the particular difficulties trainees experience in learning procedural skills, including prevention of perforations, proper positioning and success of coils within the aneurysm.

The Nanostructure of Alkyl-Sulfonate Ionic Liquids: Two 1-Alkyl-3-methylimidazolium Alkyl-Sulfonate Homologous Series

The functionalization of polymers with sulfonate groups has many important uses, ranging from biomedical applications to detergency properties used in oil-recovery processes. In this work, several ionic liquids (ILs) combining 1-alkyl-3-methylimidazolium cations [C_nC₁im]⁺ (4 ≤ n ≤ 8) with alkyl-sulfonate anions [C_mSO₃]^- (4 ≤ m ≤ 8) have been studied using molecular dynamics simulations, totalizing nine ionic liquids belonging to two homologous series. The radial distribution functions, structure factors, aggregation analyses, and spatial distribution functions reveal that the increase in aliphatic chain length induces no significant change in the structure of the polar network of the ILs. However, for imidazolium cations and sulfonate anions with shorter alkyl chains, the nonpolar organization is conditioned by the forces acting on the polar domains, namely, electrostatic interactions and hydrogen bonding.

Rist Guide Catheter for Endovascular Procedures: Initial Case Series from a Single Center

BACKGROUND

The transradial approach (TRA) for endovascular procedures has become a frequent practice in neurointervention. Advantages of the TRA include less access-site complications, early ambulation, and less postprocedural pain. The Rist 079 radial access guide catheter (Medtronic) is the first device designed specifically for neurointerventions performed through the TRA. In this study, we report our initial experience with the Rist catheter in a variety of neurointerventional procedures, aiming to evaluate the performance of this device and discuss its limitations.

METHODS

A prospectively maintained database was retrospectively searched to identify patients who underwent procedures using the Rist catheter. Information on demographics, procedural details, and complications was recorded.

RESULTS

Seventy-eight patients were included in the study, with a mean age of 60.3 years (range, 25-92 years); 45 (57.7%) were men. The interventional or diagnostic procedure was successfully completed in 77 patients (98.7%). The radial artery was the primary access-site choice in 71 patients (91%). The most frequent type of procedures performed were coiling or stent-assisted coiling (16.7%) and angioplasty and stenting (16.7%), followed by middle meningeal artery embolization (14.1%). Crossover to femoral artery access while maintaining use of the Rist was done in 5 cases (6.4%). Reasons for access or procedural failure included anatomical anomaly of the target vessel, unfavorable geometry of the great vessels, and proximal tortuosity of the supra-aortic vessels.

CONCLUSION

We demonstrated a high success rate with use of the Rist catheter system for a variety of procedures.

Contour-Assisted coiling with jailed microcatheter May result in better occlusion (CoCoJaMBO) in wide-necked intracranial aneurysms: Proof of principle and immediate angiographic results

PURPOSE

Wide-necked bifurcation aneurysms, partially thrombosed, and recurrences of large and giant aneurysms are challenging to treat. We report our preliminary experience with a Contour-assisted coiling technique and discuss the periprocedural safety, feasibility, and effectiveness of the approach.

METHODS

We retrospectively reviewed consecutive patients who received endovascular treatment for intracranial aneurysms with an intra-aneurysmal flow disruptor (Contour) at two neurovascular centres between October 2018 and December 2020 and identified patients treated with a combination of Contour and platinum coils. Clinical and procedural data were recorded.

RESULTS

For this analysis, 8 patients (5 female) aged 60.1  ±  9.2 years on average were identified. Three of 8 aneurysms were associated with previous acute subarachnoid hemorrhage (SAH). The mean average dome height was 12.8  ±  7.6 mm, mean maximum dome width 10.3  ±  5.4 mm, and neck width 5.5  ±  2.5 mm. The mean dome-to-neck ratio was 1.9  ±  1.0. Immediate complete occlusion of the aneurysm was seen in 5 of 8 cases. In one SAH patient, a parent vessel was temporarily occluded but could be reopened rapidly. One device detached prematurely without any sequelae. No other procedural adverse events were recorded.

CONCLUSION

From this initial experience, Contour with adjunctive coiling is a safe and technically feasible method for endovascular treatment of large, wide-necked, partially thrombosed, recurrent, or ruptured bifurcation aneurysms. Further studies with larger numbers of patients and longer follow-up are needed to confirm our results.

pCONUS 2 and pCONUS 2-HPC in the treatment of wide-necked intracranial aneurysms: Multicentre UK experience

BACKGROUND/PURPOSE

pCONUS 2 and pCONUS 2-HPC are neck-bridging devices that provide coiling support in the endovascular treatment of wide-necked intracranial aneurysms. To date, limited multicentre data has been published. This study provides the first pooled data from multiple UK centres regarding outcomes for these devices covering the periprocedural period to 6-month follow-up.

MATERIALS/METHODS

This retrospective, single-arm study assessed 65 patients treated over 3 years from the time of procedure to 6 months post-procedure across four UK centres. Data collected included patient demographics, aneurysm characteristics and antiplatelet regimens. Outcome measures were angiographic results and procedure-related complications from the immediate periprocedural period to 6-month follow-up.

RESULTS

Fifty-four unruptured (83.1%) and 11 ruptured (16.9%) aneurysms were treated. Fifty-five aneurysms were located in the anterior circulation (87.7%). There were four device-related intraprocedural complications: three cases of asymptomatic, temporary thrombus formation and one mortality associated with branch vessel occlusion and aneurysm re-bleeding in a ruptured case. There were no post-procedural device-related complications. Satisfactory occlusion was achieved in 58/65 procedures (89.2%) at time of treatment and in 44/60 (73.3%) at 6 months. Satisfactory occlusion correlated with aneurysm size and coiling packing density. Retreatment was required for five unruptured cases (7.7%) and was straightforward with the device in situ.

CONCLUSION

pCONUS 2 and pCONUS 2-HPC have good short-term safety profiles. The use of pCONUS 2-HPC in the acute treatment of ruptured aneurysms with postprocedural SAPT is feasible. The devices have an intraprocedural complication rate of 4/65 (6.2%) across multiple UK centres, including a single death (1.5%).

Dolichoarteriopathy of Common Carotid Artery: An Unusual Entity

Dolichoarterial disease of the carotid arteries refers to elongated arteries with tortuous, coiling, and kinking anatomy. This morphology is usually met in the elderly and not associated with atherosclerotic risk factors. Current practice reserves surgical correction only in symptomatic patients. Significant tortuosity index may be associated with stroke and poses extra difficulties to the endovascular passage of guidewires and catheters for the treatment of extra- and intracranial vascular lesions. This article presents a typical case of bilateral dolichoarteriopathy of the common carotid artery and stresses the need for further categorization of the particular morphology based on modern angiography techniques and three-dimensional reconstruction software.

Tubridge flow diverter alone vs. Tubridge flow diverter and coils for the treatment of intracranial aneurysms: A propensity score matching analysis

Background

The study was designed to assess the clinical performance of a tubridge flow diverter (TFD) in the treatment of intracranial aneurysms and to compare the efficacy and safety between intracranial aneurysms treated with TFD alone and TFD combined with coiling.

Methods

In this retrospective study, patients treated with the TFD alone or TFD combined with coiling between June 2018 to November 2022 were included. The patient demographics, the characteristics of the aneurysm, and the treatment outcomes between the two groups were compared. Propensity score matching was performed to match the variables with a significant difference between groups.

Results

In the current study, data from 93 consecutive patients including 104 aneurysms treated with TFD were analyzed. In total, 43 patients with 49 aneurysms were treated with TFD alone, and 50 patients with 55 aneurysms were treated with TFD combined with coiling. Aneurysms in the TFD combined with the coiling group were larger (12.9 ± 8.6 vs. 8.7 ± 8.8 mm, P = 0.016) and more likely to be saccular (92.7% vs. 75.5%, P = 0.027) than in the TFD alone group. No significant difference was observed between the two groups in terms of perioperative complication rate. During the follow-up period, the complete occlusion rate in the TFD combined with the coiling group was higher (80.0% vs. 43.8%, P = 0.001) than in the TFD alone group. These results were further confirmed using a propensity score matching analysis.

Conclusion

TFD combined with coiling can be a safe and effective alternative option for the treatment of complex aneurysms. Given the potential risks of these therapeutic modalities, thus very careful consideration is required on an individual patient basis.

The Exceedingly Rapid Development of an Intracranial Aneurysm

Despite significant diagnostic and technical progress in managing intracranial aneurysms, there are still open questions in understanding their pathophysiology: how fast can they form and grow? We had the chance to observe the "de novo" genesis and rupture of an aneurysm of a left MCA posterior trunk M3 branch within 14 days in one of our patients. We were in the position to compare an initially inconspicuous vessel, assessed during a diagnostic cerebral angiogram with 3D acquisitions, performed as an elective follow-up to monitor the decade stability of a transitional aneurysm in the same vascular territory, and the same vessel only two weeks after, harboring a new small ruptured aneurysm. Several studies along the intracranial aneurysms' pathophysiology have been reported but primarily oriented toward identifying uncommon conditions such as inherent defects in collagen synthesis, genetic or familial factors, or basic anatomic variations or abnormalities in the cerebral vasculature. Suppose this case report does not pretend to provide a clear answer to these questions. However, it is up to date, the shortest time (14 days) reported in the literature for a well-documented "de novo" genesis and rupture of an intracranial aneurysm "in vivo" in humans. The purpose of this case report is not only to underscore the unpredictability of this vascular disease but, even more, to support the idea that further investigation, with more modern methodologies, is of paramount importance in determining the etiopathogenesis and behavior of this stealthy disease.

Endovascular coiling of recurrent trapped pseudoaneurysm of petrous ICA across the distal barrier: When the other way round is the only way around!

BACKGROUND

The pseudoaneurysms of the internal carotid artery (ICA) at the skull base form a unique subset of craniofacial pseudoaneurysms with varied diagnostic and therapeutic challenges. Recurrence in a surgically treated pseudoaneurysm may become a nightmare due to very limited number of open and endovascular options.

REPORT

We report a rare case of recurrent pseudoaneurysm of petrous ICA, which presented with massive epistaxis following an initial successful occlusion by surgical trapping of the parent arterial segment with surgical clip. Cerebral angiography revealed filling of the pseudoaneurysm by small arterial channels from the external carotid, contralateral internal carotid and basilar arterial branches and emptying through the "slipped" distal clip. After a meticulous analysis of the cerebral angiogram, the recurrent pseudoaneurysm was eventually embolized retrogradely through the "slipped" clip after crossing the anterior communicating artery taking a contralateral internal carotid access.

CONCLUSION

Scrupulous planning and execution of ICA pseudoaneurysms is necessary to prevent recurrence. Naturally occuring collateral routes through the Circle of Willis aid in treatment of "unreachable" vascular lesions.

Outcome of ruptured anterior communicating artery aneurysm treatment compared between surgical clipping and endovascular coiling: A single-center analysis

The optimal treatment modality for ruptured anterior communicating artery (ACoA) aneurysms is unclear. Therefore, in this study, we aimed to compare the outcomes of endovascular coiling and surgical clipping to treat ruptured ACoA aneurysms. A retrospective analysis of 213 consecutive patients with ruptured AcoA aneurysms, who were treated with coiling or clipping between January 2010 and December 2020, was conducted. Of the 213 patients, 94 and 119 underwent clipping and coiling, respectively. The mean age was higher in the coiling group than in the clipping group (60.3 ± 13.2 vs. 53.5 ± 13.4, P < .001). The mean diameter of the aneurysmal neck was larger in the clipping group (3.4 mm vs. 3.0 mm, P = .022), whereas the dome-to-neck ratio (1.53 ± 0.52 vs. 1.70 ± 0.60, P = .031) and aspect ratio (1.67 ± 0.51 vs. 1.92 ± 0.77, P = .005) were larger in the coiling group. The prevalence of vasospasm was higher in the clipping than in the coiling group (42.6% vs. 26.9%, P = .016). The coiling group had a shorter mean intensive care unit hospitalization (18.3 vs. 12.1, P = .002) and more frequently showed favorable outcomes (Glasgow Outcome Scale 4, 5; 57.4% vs 73.1%, P = .016) compared to the clipping group. Multivariable logistic analysis showed that good initial WFNS grade (odds ratio [OR] = 6.69, 95% confidence interval [CI]: 2.69-16.65, P < .001), treatment with coiling (OR = 3.67, 95% CI: 1.70-7.90, P = .001), and absence of the need for cerebrospinal fluid diversion (OR = 5.21, 95% CI: 2.38-11.39, P < .001) were independent predictors of favorable outcomes in patients with ruptured ACoA aneurysms. Ruptured ACoA aneurysms can be safely and effectively treated using both clipping and coiling modalities. However, it may be beneficial to consider coiling as the first option for treating these aneurysms.

Initial experience of using a large-bore (0.096″ inner diameter) access catheter in neurovascular interventions

INTRODUCTION

The purpose of this study was to report our initial experience of using a large-bore (0.096″ inner diameter) access catheter in neurovascular interventions.

METHODS

Data were retrospectively collected from 5 sites in the US for neurovascular procedures performed using a large-bore access catheter. The effectiveness outcome was technical success, defined as the access catheter's successfully reaching its target vessel without conversion to direct carotid puncture or to a smaller-bore access catheter and successfully completing the intended neurointervention.

RESULTS

One hundred and thirteen procedures performed in 112 patients were included in this study. The mean age of the patients was 67.5 years (SD 16.2), and about half (49.1%) were female. The most common primary access sites were the femoral (64.6%) or radial (32.7%) artery. Challenging anatomic variations included severe vessel tortuosity (26/81, 32.1%), type II aortic arch (17/88, 19.3%), type III aortic arch (14/88, 15.9%), bovine arch (16/104, 15.4%), severe angle (<30°) between the subclavian and target vessel (11/74, 14.9%), and subclavian loop (7/79, 8.9%). The median access time to branch view was 18 min (IQR 11-28, N = 75). The technical success rate was 94.7%. Two dissections (1.8%) were related to the large-bore access catheter. Access site complications occurred in 2 patients (1.8%). Four additional symptomatic periprocedural complications not related to the large-bore access catheter occurred (7.1%).

CONCLUSION

For neurovascular interventions, a 0.096″ inner diameter access catheter could be used with both femoral and radial arterial approaches, had a high technical success rate, and had a low rate of periprocedural complications.

European Stroke Organisation (ESO) guidelines on management of unruptured intracranial aneurysms

Unruptured intracranial aneurysms (UIA) occur in around 3% of the population. Important management questions concern if and how to perform preventive UIA occlusion; if, how and when to perform follow up imaging and non-interventional means to reduce the risk of rupture. Using the Standard Operational Procedure of ESO we prepared guidelines according to GRADE methodology. Since no completed randomised trials exist, we used interim analyses of trials, and meta-analyses of observational and case-control studies to provide recommendations to guide UIA management. All recommendations were based on very low evidence. We suggest preventive occlusion if the estimated 5-year rupture risk exceeds the risk of preventive treatment. In general, we cannot recommend endovascular over microsurgical treatment, but suggest flow diverting stents as option only when there are no other low-risk options for UIA repair. To detect UIA recurrence we suggest radiological follow up after occlusion. In patients who are initially observed, we suggest radiological monitoring to detect future UIA growth, smoking cessation, treatment of hypertension, but not treatment with statins or acetylsalicylic acid with the indication to reduce the risk of aneurysm rupture. Additionally, we formulated 15 expert-consensus statements. All experts suggest to assess UIA patients within a multidisciplinary setting (neurosurgery, neuroradiology and neurology) at centres consulting >100 UIA patients per year, to use a shared decision-making process based on the team recommendation and patient preferences, and to repair UIA only in centres performing the proposed treatment in >30 patients with (ruptured or unruptured) aneurysms per year per neurosurgeon or neurointerventionalist. These UIA guidelines provide contemporary recommendations and consensus statement on important aspects of UIA management until more robust data come available.

Intrasaccular Flow Disruptor-Assisted Coiling of Intracranial Aneurysms Using the Novel Contour Neurovascular Systems and NEQSTENT: A Single-Center Safety and Feasibility Study

Background: Intrasaccular flow disruptors (IFD) have been introduced in the treatment of intracranial aneurysms (IAs) to overcome the low aneurysm occlusion rate and the high recanalization rate of the coiling technique. Among them, the Contour Neurovascular System (CNS) and the Neqstent (NQS) were designed to reconstruct the aneurysmal neck and both can be used as assisting coiling devices. We aimed to report our preliminary experience with the flow disruptor-assisted coiling (IFD-AC) technique. Methods: We performed a retrospective analysis of prospectively collected data of all patients with IAs treated with the IFD-AC. Results: Between February 2021 and April 2022, we treated 15 IAs with the IFD-AC: 10 ruptured and 5 unruptured. The IFD-AC was successfully performed in 13 cases, with a post-operative RROC 1 in 12 cases (92.3%) and RROC 2 in 1 case (7.7%). There was one ischemic event (6.7%) and no hemorrhagic complications. Twelve patients underwent a mid-term radiologic follow-up: Ten IAs (83.4%) presented an adequate occlusion, while 2 (16.7%) had a recurrence. Conclusions: The IFD-AC, both with the CNS and the NQS, seems a safe technique with promising efficacy profile. The IFD-AC has proved to be safe without antiplatelet therapy in ruptured cases. Further studies are needed to confirm our preliminary results.

Feasibility study, immediate and early angiographic results

PURPOSE

Various adjunctive devices have been reported to be helpful during the endovascular coiling of complex, wide-necked cerebral aneurysms. This study aimed to describe the utilization of a recently introduced intrasaccular neck-bridging implant specifically designed to facilitate coil embolization.

METHODS

We retrospectively reviewed eight consecutive patients who underwent treatment for intracranial aneurysms with the Nautilus intrasaccular bridging system between February 2022 to May 2022. We evaluated the angiographic appearances of treated aneurysms at the end of the procedure and early follow-up, the clinical status and complications.

RESULTS

Eight patients with eight cerebral aneurysms (3 men and 5 women, mean age 52.8 years (range 39-66) were analyzed. Five of the treated aneurysms were managed in an acute case scenario. There were no technical difficulties while executing the technique. No other procedural adverse events were documented. Immediate complete occlusion of the aneurysm was seen in 6 patients, neck remnant in 1 and stable aneurysm reperfusion in one case. Early radiological follow-up was available in five patients, and the observed occlusion rates were - RR class I in all radiologically screened aneurysms.

CONCLUSION

Nautilus-assisted coil embolization represents a rapid and safe solution for complex cerebral aneurysms. In our opinion this device symbolizes a significant step forward in treating intracranial aneurysms. We believe that the technique's actual value consists of the fact that the device is fully compatible with the modern low-profile microcatheter technology and does not involve the need for antiplatelet medications.

Crucial Convolution: Genetic and Molecular Mechanisms of Coiling during Epididymis Formation and Development in Embryogenesis

As embryonic development proceeds, numerous organs need to coil, bend or fold in order to establish their final shape. Generally, this occurs so as to maximise the surface area for absorption or secretory functions (e.g., in the small and large intestines, kidney or epididymis); however, mechanisms of bending and shaping also occur in other structures, notably the midbrain–hindbrain boundary in some teleost fish models such as zebrafish. In this review, we will examine known genetic and molecular factors that operate to pattern complex, coiled structures, with a primary focus on the epididymis as an excellent model organ to examine coiling. We will also discuss genetic mechanisms involving coiling in the seminiferous tubules and intestine to establish the final form and function of these coiled structures in the mature organism.

Evolution of the patient-first approach: a dual-trained, single-neurosurgeon experience with 2002 consecutive intracranial aneurysm treatments

OBJECTIVE

The paradigm for intracranial aneurysm (IA) treatment is shifting toward a hybrid approach involving open and endovascular techniques. The authors chronicled the evolution of IA treatment by retrospectively examining a large series of IA cases treated by a single dual-trained neurosurgeon, focusing on evolving technology relative to the choice of treatment options, perioperative morbidity, and mortality.

METHODS

The aneurysm database at the authors' institution was searched to identify consecutive patients treated with endovascular or open microsurgical approaches by one neurosurgeon during an 18-year time span. Patients were included regardless of IA rupture status, location or morphology, or treatment modality. Data collected were baseline clinical characteristics, aneurysm size, treatment modality, operative complications, in-hospital mortality, and retreatment rate.

RESULTS

A total of 1858 patients with 2002 IA treatments were included in the study. Three-hundred fifty IAs (17.5%) were ruptured. Open microsurgery was performed in 504 aneurysms (25.2%) and endovascular surgery in 1498 (74.8%). Endovascular IA treatments trended toward a growing use of flow diversion during the last 11 years. In-hospital mortality was 1.7% overall, including 7.0% in ruptured and 0.5% in unruptured cases. The overall complication rate was 3.3%, including 3.4% for microsurgical cases and 3.3% for endovascular cases. The rate of retreatment was 3.6% after clipping and 10.7% for endovascular treatment.

CONCLUSIONS

This study demonstrates complementary use of open and endovascular approaches for IA treatment. By customizing treatment to the patient, comparable rates of procedural complications, mortality, and retreatment were achieved for both endovascular and microsurgical approaches.

Results of the pToWin Study: Using the pCONUS Device for the Treatment of Wide-Neck Intracranial Aneurysms

Coil embolization has become a well-established option for the treatment of intracranial aneurysms. Yet, wide-neck bifurcation aneurysms (WNBAs) remain a challenge. The pCONUS is the first generation of a stent-like implant for the bridging of WNBAs to enable coiling. The pToWin study was a prospective, single-arm, multicenter study conducted to analyze the safety and efficacy of the pCONUS in the treatment of WNBAs. The primary effectiveness endpoint was the rate of adequate occlusion of the aneurysm at 3–6 and 7–12 months. The primary safety endpoint was the occurrence of major ipsilateral stroke or neurological death during the follow-up. A total of 115 patients were included. Aneurysm locations were the middle cerebral artery in 52 (45.2%), the anterior communicating artery in 35 (30.4%), the basilar artery in 23 (20%), the internal carotid artery terminus in three (2.6%), and the pericallosal artery in two (1.7%) patients. Treatment was successfully performed in all but one patient. The morbi-mortality rate was 1.9% and 2.3% at 3–6 and 7–12 months, respectively. Of the aneurysms, 75.0% and 65.6% showed adequate occlusion at 3–6 and 7–12 months, respectively. pCONUS offers a safe and reasonably effective treatment of WNBAs, demonstrated by acceptable adequate aneurysm occlusion and low rates of adverse neurologic events.

The physical basis of mollusk shell chiral coiling

Snails are model organisms for studying the genetic, molecular, and developmental bases of left-right asymmetry in Bilateria. However, the development of their typical helicospiral shell, present for the last 540 million years in environments as different as the abyss or our gardens, remains poorly understood. Conversely, ammonites typically have a bilaterally symmetric, planispiraly coiled shell, with only 1% of 3,000 genera displaying either a helicospiral or a meandering asymmetric shell. A comparative analysis suggests that the development of chiral shells in these mollusks is different and that, unlike snails, ammonites with asymmetric shells probably had a bilaterally symmetric body diagnostic of cephalopods. We propose a mathematical model for the growth of shells, taking into account the physical interaction during development between the soft mollusk body and its hard shell. Our model shows that a growth mismatch between the secreted shell tube and a bilaterally symmetric body in ammonites can generate mechanical forces that are balanced by a twist of the body, breaking shell symmetry. In gastropods, where a twist is intrinsic to the body, the same model predicts that helicospiral shells are the most likely shell forms. Our model explains a large diversity of forms and shows that, although molluscan shells are incrementally secreted at their opening, the path followed by the shell edge and the resulting form are partly governed by the mechanics of the body inside the shell, a perspective that explains many aspects of their development and evolution.

Endovascular Management of Cerebral Aneurysms of the Posterior Cerebral Artery

Purpose: To investigate the safety and efficacy of endovascular embolization of cerebral aneurysms at the P1–P3 segments of the posterior cerebral artery (PCA).

Materials and Methods: Seventy-seven patients with 77 PCA aneurysms who were treated with endovascular embolization were enrolled, including 35 (45.5%) patients with ruptured aneurysms and 42 (54.5%) with unruptured ones. The pretreatment clinical data and aneurysm occlusion status after treatment and at follow-up were analyzed.

Results: All patients were successfully treated endovascularly, including coiling alone in 10 (13.0%) patients, stent-assisted coiling in 18 (23.4%), parent artery occlusion in 25 (32.5%), and pipeline embolization device (PED) in 24 (31.2%). Complete occlusion was achieved in 48 (62.3%) aneurysms, residual neck in 4 (5.2%), and residual aneurysm in the other 25 (32.5%) at the end of embolization. Periprocedural complications occurred in eight patients, including acute thrombosis in seven (9.1%) and intraprocedural subarachnoid hemorrhage in one (1.3%), with the total complication rate of 10.4%. Follow-up was performed in 60 patients (77.9%) for 42 ± 11 months; the mRS score was 0–2 in 55 (91.7%) patients, three in four patients (6.7%), and six in one patient (1.7%). Fifty-three (88.3%) patients (53 aneurysms) had stable or complete occlusion, and seven (11.7%) patients had aneurysm recurrence or residual aneurysm. Among 19 patients treated with PED at follow-up, 15 aneurysms (78.9%) proceeded to complete occlusion while four (21.1%) aneurysms showed residual aneurysm.

Conclusion: Endovascular embolization remains a good choice of treatment with high safety and efficacy for posterior cerebral artery aneurysms.

Post-Tracheostomy Vascular Injury to the Anomalous Thymic Branch Managed by Endovascular Coiling

BACKGROUND

Tracheostomy-related arterial haemorrhage can be devastating especially if arising from an obscure anomalous vessel which can potentially complicate treatment decision.

METHODS

We report a case of non-Hodgkin's lymphoma with upper airway obstruction, who had profuse bleeding, post-tracheostomy, from the stomal site. CT angiography showed presence of a pseudoaneurysm adjacent to the tracheostomy site which was confirmed on catheter angiography to be arising from anomalous thymic branch of right common carotid artery (CCA). Superselective cannulation of the anomalous thymic artery was done using a microcatheter with subsequent coil embolization.

RESULTS

Post-coiling, the bleeding stopped immediately and the patient recovered. He was under oncology care till 3 months following embolization and was doing well.

CONCLUSIONS

The emergency physicians should be aware of this rare variation of thymic artery while performing tracheostomy. Ultrasound as point-of-care device may help mitigate these complications. Endovascular embolization is a minimally invasive and effective management option for an injured arterial branch from a tracheostomy.

Short- and Long-Term Safety and Efficacy of Self-Expandable Leo Stents Used Alone or with Coiling for Ruptured and Unruptured Intracranial Aneurysms: A Retrospective Observational Study

To assess the efficacy and safety of the Leo stent used alone or with coiling to treat complex intracranial aneurysms (IAs) not eligible for simple or balloon-assisted coiling, this single-center retrospective study included consecutive adults with ruptured or unruptured IAs treated in 2011-2018 by stenting with or without coiling. The indication for stenting was IA complexity precluding simple or balloon-assisted coiling. Extensive data on the patients, IAs, antiplatelet treatments, procedures, and outcomes over the first 36 months were collected. Risk factors for early complications (univariate analysis) and delayed ischemia (multivariate analysis) were sought. We include 64 patients with 66 IAs. The procedural success rate was 65/66 (98.5%). Obliteration was Raymond Roy class I or II for 85% of IAs. Six patients died including four of the 12 patients presenting with subarachnoid hemorrhage, which was the only significant risk factor for early major complications. At 1 month, 45/64 (69%) had no disabilities. No rebleeding was reported. Ischemia was detected by routine MRI in 20 (35%) of the 57 patients with long-term data and was asymptomatic in 14. The stent-within-a-stent configuration was the only independent risk factor for ischemia. The Leo stent used alone or with coils to manage challenging IAs was associated with a high procedural success rate and complete or nearly complete IA obliteration of 85% of IAs. The high frequency of ischemia is ascribable to our use of routine serial MRI. In patients with bleeding, the Leo stent was associated with an excess risk of early, major, intracranial complications, as compared to patients without bleeding. Long-term follow-up was marked by the occurrence of ischemic events in the vascular territory of the stent, mostly silent.

Simulation of Subrapid Solidification and Secondary Cooling for the Strip Casting of IF Steel

A combination of droplet solidification tester and confocal laser scanning microscope was used to simulate subrapid solidification and secondary cooling process pertinent to the strip casting. The IF steel droplet had a delamination structure and the bottom part went through sub-rapid solidification. During secondary cooling, γ/α transformation mechanism belonged to interface-controlled massive transformation and the ferrite grains grew quickly. With the increase of cooling rate, the γ/α transformation temperature decreased and the incubation period and phase transformation duration reduced. The hardness showed a slight increase due to fine-grain strengthening. With coiling temperature increasing from 600 °C to 800 °C, the grain size became larger, precipitates became coarse, and defects in grain were recovered. Consequently, the hardness decreased.

Association Between Hospital Volumes and Clinical Outcomes for Patients With Nontraumatic Subarachnoid Hemorrhage

Background

Previous studies of patients with nontraumatic subarachnoid hemorrhage (SAH) suggest better outcomes at hospitals with higher case and procedural volumes, but the shape of the volume‐outcome curve has not been defined. We sought to establish minimum volume criteria for SAH and aneurysm obliteration procedures that could be used for comprehensive stroke center certification.

Methods and Results

Data from 8512 discharges in the National Inpatient Sample (NIS) from 2010 to 2011 were analyzed using logistic regression models to evaluate the association between clinical outcomes (in‐hospital mortality and the NIS‐SAH Outcome Measure [NIS‐SOM]) and measures of hospital annual case volume (nontraumatic SAH discharges, coiling, and clipping procedures). Sensitivity and specificity analyses for the association of desirable outcomes with different volume thresholds were performed. During 8512 SAH hospitalizations, 28.7% of cases underwent clipping and 20.1% underwent coiling with rates of 21.2% for in‐hospital mortality and 38.6% for poor outcome on the NIS‐SOM. The mean (range) of SAH, coiling, and clipping annual case volumes were 30.9 (1–195), 8.7 (0–94), and 6.1 (0–69), respectively. Logistic regression demonstrated improved outcomes with increasing annual case volumes of SAH discharges and procedures for aneurysm obliteration, with attenuation of the benefit beyond 35 SAH cases/year. Analysis of sensitivity and specificity using different volume thresholds confirmed these results. Analysis of previously proposed volume thresholds, including those utilized as minimum standards for comprehensive stroke center certification, showed that hospitals with more than 35 SAH cases annually had consistently superior outcomes compared with hospitals with fewer cases, although some hospitals below this threshold had similar outcomes. The adjusted odds ratio demonstrating lower risk of poor outcomes with SAH annual case volume ≥35 compared with 20 to 34 was 0.82 for the NIS‐SOM (95% CI, 0.71–094; P=0.0054) and 0.80 (95% CI, 0.68–0.93; P=0.0055) for in‐hospital mortality.

Conclusions

Outcomes for patients with SAH improve with increasing hospital case volumes and procedure volumes, with consistently better outcomes for hospitals with more than 35 SAH cases per year.

Endovascular Treatment of Small Wide-Neck Bifurcation Aneurysms with Single Solitaire AB Stent Technique

BACKGROUND AND PURPOSE

We present our experience in using the single Solitaire AB stent for small wide-neck bifurcation aneurysms (WNBAs).

MATERIALS AND METHODS

During 18 months, 20 small (the largest width <10 mm) WNBAs were treated with the single Solitaire AB stent-assisted coiling. The patients were 12 women and 8 men, with a mean age of 52 years (range: 36-66 years). The mean aneurysm size was 4.2 mm (2-9 mm) and mean neck size was 3.9 mm (2-9 mm). Results at follow-up were graded as complete occlusion, neck remnant, or residual aneurysm.

RESULTS

All 20 small WNBAs were adequately occluded after a single Solitaire AB stent placement. There were no procedural ruptures and no thromboembolic complications occurred. Two patients developed a transient neurological deficit. In 20 patients with angiographic follow-up at 6 months, 16 (80%) aneurysms remained adequately occluded. Clinical follow-up in the 20 patients revealed mRS 0-2 in all.

CONCLUSIONS

Single Solitaire AB stent-assisted coil embolization for small WNBAs was safe and effective.

Visceral Artery Aneurysms Embolization and Other Interventional Options: State of the Art and New Perspectives

Visceral artery aneurysms (VAAs) are rare, usually asymptomatic and incidentally discovered during a routine radiological examination. Shared guidelines suggest their treatment in the following conditions: VAAs with diameter larger than 2 cm, or 3 times exceeding the target artery; VAAs with a progressive growth of at least 0.5 cm per year; symptomatic or ruptured VAAs. Endovascular treatment, less burdened by morbidity and mortality than surgery, is generally the preferred option. Selection of the best strategy depends on the visceral artery involved, aneurysm characteristics, the clinical scenario and the operator's experience. Tortuosity of VAAs almost always makes embolization the only technically feasible option. The present narrative review reports state of the art and new perspectives on the main endovascular and other interventional options in the treatment of VAAs. Embolization techniques and materials, use of covered and flow-diverting stents and percutaneous approaches are accurately analyzed based on the current literature. Visceral artery-related considerations and targeted approaches are also provided and discussed.

Symptomatic internal carotid artery dissection and kinking in a patient with fibromuscular dysplasia

Isolated dissection of the internal carotid artery (ICA) is rare in young patients and is a cause for strong suspicion of fibromuscular dysplasia (FMD), especially when associated with artery elongation and tortuosity. The natural history of cerebrovascular FMD is unknown and management of symptomatic patients can be challenging. We report the case of a 44-year-old female patient with a history of transient ischemic attack in the absence of cardiovascular risk factors, associated with an isolated left ICA dissection and kinking. Carotid duplex ultrasound confirmed the diagnosis of dissection and demonstrated severe stenosis of the left ICA. The patient underwent surgical repair and histopathological evaluation confirmed the diagnosis of FMD with dissection. An autogenous great saphenous vein bypass was performed and the patient had an uneventful recovery. Cervical carotid artery dissection can be related to underlying arterial pathologies such as FMD, and the presence of ICA tortuosity highlights certain peculiarities for optimal management, which might be surgical.

Unassisted and multiple microcatheter coiling of distal basilar aneurysms: Outcomes and literature review

PURPOSE

The best treatment for distal basilar artery aneurysms is controversial. We aimed to review our single-centre experience with coil embolisation of aneurysms at this location and compare it with the surgical and endovascular literature.

METHODS

Forty-two aneurysms in a distal basilar location in 42 consecutive patients (15 ruptured and 27 unruptured) were treated endovascularly from 2010 to 2015. Unassisted single and multiple microcatheter coil embolisation alone was used in all cases. We studied our immediate and long-term anatomical results, operative complications, and outcome.

RESULTS

The immediate angiographic results showed complete occlusion in 34 (81%), a neck remnant in seven (16.6%) and a residual aneurysm in one patient (2.4%). There were two thromboembolic events (4.7%) without clinical sequelae; therefore, the operative morbidity and mortality were zero.Three patients with ruptured aneurysms (7.1%) died due to complicated vasospasm. Thirty-nine patients (93%) had clinical and MR imaging follow-up (mean 32.3 months ± 18.6, range from 12 to 66 months). There was recanalization in 30.8% with a retreatment rate of 15.3% and no new bleedings. The aneurysm size was the most important predictor of early anatomical outcome and recurrence.

CONCLUSION

Unassisted and multiple microcatheter coiling is a safe treatment for distal basilar aneurysms. Early anatomical results and recurrence depend on the aneurysm size. Morbidity and mortality are lower and recurrence rates are higher in comparison with clipping or other adjunctive endovascular techniques.

pCONUS 2 and pCONUS 2-HPC for the treatment of wide-necked intracranial aneurysms: Periprocedural, 6-month, and early 2-year follow-up outcomes

BACKGROUND/PURPOSE

pCONUS 2 and pCONUS 2-HPC are novel neck-bridging devices designed to support endovascular coil occlusion of wide-necked intracranial bifurcation aneurysms. This study summarises periprocedural outcomes, 6-month, and early 2-year follow-up results following its introduction in an interventional neuroradiology centre.

MATERIALS/METHODS

This prospective, single-arm study assessed 20 aneurysms treated over a 40 month time period from time of procedure to 2 years post-procedure. Data collected included patient demographics, aneurysm features, and intraprocedural, 6-month, and 2-year post-procedural complications and angiographic features.

RESULTS

The mean age of the cohort was 59+-SD 7.7 years. 16 unruptured aneurysms were treated (pCONUS 2 13/16, pCONUS 2-HPC 3/16) and 4 ruptured aneurysms were treated with pCONUS 2-HPC. Unruptured cases received dual antiplatelet therapy pre- and post-procedure while ruptured cases received single antiplatelet therapy. 9/20 aneurysms were located at the MCA bifurcation and 7/20 at the basilar tip. The remaining 4 aneurysms were at various bifurcations in the anterior circulation. 11/20 were small (<10mm) and 9/20 were large (10-25mm). There was one periprocedural complication: a retroperitoneal bleed. There were no post-procedural intracranial complications or at 6-months follow-up. At 6 months, satisfactory occlusion was achieved in 94% of cases (15/16). There was one delayed death at 2-year follow-up from an unrelated cause.

CONCLUSION

pCONUS 2 and pCONUS 2-HPC have excellent short and medium-term safety profiles and clinical outcomes with no procedure-related mortality or morbidity and good occlusion rates at 6-month follow-up. The use of pCONUS 2-HPC with single antiplatelet therapy is feasible and did not cause any complications.

Endovascular Treatment of Intracranial Aneurysms

Traditionally, surgical clipping was the only available treatment modality for intracranial aneurysms. However, in the last few decades, the endovascular therapy of intracranial aneurysms (IAs) has seen a tremendous evolution and development. From coiling to flow diversion and flow disruptor devices, endovascular treatment modalities have increased in number and received broader indications throughout the years. In this review article, the treatment modalities for the endovascular management of IAs are presented, emphasizing newer devices and technologies.

Follow-Up DSA at Day 9 ± 2 after Subarachnoid Hemorrhage Predicts Long-Term Recurrence of Ruptured Cerebral Aneurysm after Coiling

Objective

The recurrence rate of coiled ruptured cerebral aneurysms is greater than that of clipped aneurysms. The aim of this study is to determine the factors that relate to the recurrence of embolized, ruptured cerebral aneurysms, and the evidence thereto.

Methods

From April 2007 through July 2017, we treated 134 ruptured cerebral aneurysm cases by coiling. DSA and/or MRI were done in 98 saccular aneurysm cases one year after the coiling. Recurrence was defined as enlargement of the aneurysm neck or contrast opacification along the aneurysm wall. A chi-square test and a logistic regression analysis were done to analyze the relationship between aneurysm recurrence and clinical factors.

Results

The median follow-up period was 58 months (interquartile range [IQR]: 33-107). Ten cases (10.2%) were subjected to aneurysm recurrence. Internal carotid artery (ICA) aneurysms proximal to the posterior communicating artery, incomplete obliteration of an aneurysm at initial embolization and postoperative DSA during day 9 ± 2, and increased contrast medium in the aneurysm at postoperative DSA during day 9 ± 2 were all statistically related to the recurrence of the aneurysm. Logistic regression analysis showed that the increased contrast medium in the aneurysm at day 9 ± 2 was statistically related to aneurysm recurrence (p <0.0001). Recurrence or retreatment of the aneurysm did not influence the outcome.

Conclusion

Complete obliteration of the aneurysm at the first session is important. Recurrence of an embolized ruptured aneurysm can be estimated by postoperative DSA at day 9 ± 2 days.