Interdisciplinary Management of Vascular Anomalies in the Head and Neck

Vascular anomalies in the head and neck area are usually rare diseases and pose a particular diagnostic and therapeutic challenge. They are divided into vascular tumours and vascular malformations. A distinction is made between benign tumours, such as infantile haemangioma, and rare malignant tumours, such as angiosarcoma. Vascular malformations are categorised as simple malformations, mixed malformations, large vessel anomalies and those associated with other anomalies. Treatment is interdisciplinary and various modalities are available. These include clinical observation, sclerotherapy, embolisation, ablative and coagulating procedures, surgical resection and systemic drug therapy. Treatment is challenging, as vascular anomalies in the head and neck region practically always affect function and aesthetics. A better understanding of the genetic and molecular biological basis of vascular anomalies has recently led to clinical research into targeted drug therapies. This article provides an up-to-date overview of the diagnosis, clinic and treatment of vascular anomalies in the head and neck region.

MR Imaging Characteristics of Solitary Fibrous Tumors of the Orbit : Case Series of 18 Patients

PURPOSE

Solitary fibrous tumor (SFT) of the orbit is a rare tumor that was first described in 1994. We aimed to investigate its imaging characteristics that may facilitate the differential diagnosis between SFT and other types of orbital tumors.

MATERIAL AND METHODS

Magnetic resonance imaging (MRI) data of patients with immunohistochemically confirmed orbital SFT from 2002 to 2022 at a tertiary care center were retrospectively analyzed. Tumor location, size, morphological characteristics, and contrast enhancement features were evaluated.

RESULTS

Of the 18 eligible patients 10 were female (56%) with a mean age of 52 years. Most of the SFTs were oval-shaped (67%) with a sharp margin (83%). The most frequent locations were the laterocranial quadrant (44%), the extraconal space (67%) and the dorsal half of the orbit (67%). A flow void phenomenon was observed in nearly all cases (94%). On the T1-weighted imaging, tumor signal intensity (SI) was significantly lower than that of the retrobulbar fat and appeared predominantly equivalent (82%) to the temporomesial brain cortex, while on T2-weighted imaging its SI remained equivalent (50%) or slightly hyperintense to that of brain cortex. More than half of the lesions showed a homogeneous contrast enhancement pattern with a median SI increase of 2.2-fold compared to baseline precontrast imaging.

CONCLUSION

The SFT represents a rare orbital tumor with several characteristic imaging features. It was mostly oval-shaped with a sharp margin and frequently localized in the extraconal space and dorsal half of the orbit. Flow voids indicating hypervascularization were the most common findings.

MRI characterization of in vitro clots at 3T and 7T: A technical note

In acute ischemic stroke, the composition of the occlusive clot can be associated with the underlying pathophysiology and the response to treatment. For these reasons, it is important to characterize the clot composition from clinical scans. We examine the ability of 3T and 7T MRI to distinguish the composition of in vitro clots, using quantitative T1 and T2*, alternatively R2*, mapping. When comparing the two field strengths, we found a tradeoff between sensitivity for clot composition and confidence in the clot depiction associated with spatial resolution. The loss of sensitivity at 7T can be mitigated by combining the T1 and T2* signals.

Management of carotid cavernous fistulas: A single center experience

Purpose

Multimodal endovascular therapy (EVT) of carotid cavernous fistula (CCF) with different approaches and a variety of available embolization material enable high occlusion rates with good clinical and functional outcome but until now there is still little evidence available. This retrospective single-center study aims to evaluate EVT of CCF with different neuroendovascular techniques regarding occlusion rates, complications and outcomes.

Materials and methods

From 2001 to 2021 59 patients with CCF were treated at our tertiary university hospital. Patient records and all imaging data including angiograms were reviewed for demographic and epidemiological data, symptoms, fistula type, number of EVTs, complications of EVT, type of embolic materials, occlusion rates and recurrences.

Results

Etiology of the CCF were spontaneous (41/59, 69.5%) post-traumatic (13/59, 22%) and ruptured cavernous aneurysms (5/59, 8.5%). Endovascular therapy was completed in one session in 74.6% (44/59). Transvenous access was most frequent (55.9% 33/59) followed by transarterial catheterization in 33.9% (20/59) and a combination of both (6/59, 10.2%). Exclusively coils were used in 45.8% (27/59), a combination of ethylene vinyl alcohol (EVOH) copolymer (Onyx) and coils in 42.4% (25/59). Complete obliteration was achieved in 96.6% of patients (57/59) with an intraprocedural-related complication rate of 5.1% (3/59) and no mortality.

Conclusion

Endovascular therapy of CCF has been shown to be safe and effective with high cure rates and low rates of intraprocedural complications and morbidity even in complex scenarios.

Spatial heterogeneity of occlusive thrombus in acute ischemic stroke: A systematic review

Following the advent of mechanical thrombectomy, occlusive clots in ischemic stroke have been amply characterized using conventional histopathology. Many studies have investigated the compositional variability of thrombi and the consequences of thrombus composition on treatment response. More recent evidence has emerged about the spatial heterogeneity of the clot or the preferential distribution of its components and compact nature. Here we review this emerging body of evidence, discuss its potential clinical implications, and propose the development of adequate characterization techniques.

Predictors of Symptomatic Intracranial Hemorrhage after Endovascular Thrombectomy in Acute Ischemic Stroke Patients with Anterior Large Vessel Occlusion-Procedure Time and Reperfusion Quality Determine

PURPOSE

We aimed to evaluate predictors of symptomatic intracranial hemorrhage (sICH) in acute ischemic stroke (AIS) patients following thrombectomy due to anterior large vessel occlusion (LVO).

METHODS

Data on stroke patients from January 2018 to December 2020 in a tertiary care centre were retrospectively analysed. sICH was defined as intracranial hemorrhage associated with a deterioration of at least four points in the National Institutes of Health Stroke Scale (NIHSS) score or hemorrhage leading to death. A smoothed ridge regression model was run to analyse the impact of 15 variables on their association with sICH.

RESULTS

Of the 174 patients (median age 77, 41.4% male), sICH was present in 18 patients. Short procedure time from groin puncture to reperfusion (per 10 min OR 1.24; 95% CI 1.071-1.435; p = 0.004) and complete reperfusion (TICI 3) (OR 0.035; 95% CI 0.003-0.378; p = 0.005) were significantly associated with a lower risk of sICH. On the contrary, successful reperfusion (TICI 3 and TICI 2b) was not associated with a lower risk of sICH (OR 0.508; 95% CI 0.131-1.975, p = 0.325). Neither the total time from symptom onset to reperfusion nor the intravenous thrombolysis was a predictor of sICH (per 10 min OR 1.0; 95% CI 0.998-1.001, p = 0.745) (OR 1.305; 95% CI 0.338-5.041, p = 0.697).

CONCLUSION

Our findings addressed the paramount importance of short procedure time and complete reperfusion to minimize sICH risk. The total ischemic time from onset to reperfusion was not a predictor of sICH.

MicroCT Can Characterize Clots Retrieved With Mechanical Thrombectomy From Acute Ischemic Stroke Patients–A Preliminary Report

Background

Characterization of the clot occluding the arteries in acute ischemic stroke received ample attention, in terms of elucidating the relationship between the clot composition, its etiology and its amenability for pharmacological treatment and mechanical thrombectomy approaches. Traditional analytical techniques such as conventional 2D histopathology or electron microscopy sample only small parts of the clot. Visualization and analysis in 3D are necessary to depict and comprehend the overall organization of the clot. The aim of this study is to investigate the potential of microCT for characterizing the clot composition, structure, and organization.

Methods

In a pilot study, we analyzed with microCT clots retrieved from 14 patients with acute ischemic stroke. The following parameters were analyzed: overall clot density, clot segmentation with various density thresholds, clot volume.

Results

Our findings show that human clots are heterogeneous in terms of CT intra-clot density distribution. After fixation in formalin, the clots display a shift toward negative values. On average, we found the mean HU values of red clots retrieved from patients to be −153 HU, with SD = 23.8 HU, for the intermediate clots retrieved from patients −193 HU, SD = 23.7 HU, and for the white clots retrieved from patients −229 HU, SD = 64.8 HU.

Conclusion

Our study shows that volumetric and density analysis of the clot opens new perspectives for clot characterization and for a better understanding of thrombus structure and composition.

Radiation exposure in the endovascular therapy of cranial and spinal dural arteriovenous fistula in the last decade: a retrospective, single-center observational study

PURPOSE

This study aims to determine local diagnostic reference levels (DRLs) in the endovascular therapy (EVT) of patients with cranial and spinal dural arteriovenous fistula (dAVF).

METHODS

In a retrospective study design, DRLs and achievable dose (AD) were assessed for all patients with cranial and spinal dAVF undergoing EVT (I) or diagnostic angiography (II). All procedures were performed at the flat-panel angiography-system Allura Xper (Philips Healthcare). Interventional procedures were differentiated according to the region of fistula and the type of procedure.

RESULTS

In total, 264 neurointerventional procedures of 131 patients with dAVF (94 cranial, 37 spinal) were executed between 02/2010 and 12/2020. The following DRLs, AD, and mean values could be determined: for cranial dAVF (I) DRL 507.33 Gy cm2, AD 369.79 Gy cm2, mean 396.51 Gy cm2; (II) DRL 256.65 Gy cm2, AD 214.19 Gy cm2, mean 211.80 Gy cm2; for spinal dAVF (I) DRL 482.72 Gy cm2, AD 275.98 Gy cm2, mean 347.12 Gy cm2; (II) DRL 396.39 Gy cm2, AD 210.57 Gy cm2, mean 299.55 Gy cm2. Dose levels of EVT were significantly higher compared to diagnostic angiographies (p < 0.001). No statistical difference in dose levels regarding the localization of dAVF was found.

CONCLUSION

Our results could be used for establishing DRLs in the EVT of cranial and spinal dAVF. Because radiation exposure to comparably complex interventions such as AVM embolization is similar, it may be useful to determine general DRLs for both entities together.

Bilateral subdural hematoma caused by spontaneous intracranial hypotension originating from a discogenic microspur successfully treated with duraplasty: A case report

Introduction

Discogenic microspurs are calcified outgrowths from the intervertebral disc which can perforate the dura, causing a leak of cerebrospinal fluid (CSF). Spontaneous leaks of the CSF present a recognized cause of spontaneous intracranial hypotension (SIH). Moreover, subdural hematomas (SDH) are a potentially severe complication of SIH.

Research question

We present a case of a bilateral subdural hematoma without orthostatic headaches caused by a discogenic microspur protruding from the T1-2 intervertebral disc. The microspur is conjectured to be the culprit of the leak by ventrally perforating the dura and catalyzing the causal chain leading to the formation of the subdural hemorrhage.

Material and methods

A 79-year woman noticed a progressive gait disturbance accompanied by a decline of short-term memory over several months without experiencing orthostatic headaches. Magnetic resonance imaging (MRI) showed extensive bilateral subdural fronto-parietal hematoma, signs of CSF hypotension (dilated venous compartments), and computed tomography (CT) myelography revealed a CSF leak originating at the T1-2 level.

Results

The leakage site was treated with microsurgical duraplasty leading to a regression of the symptoms and complete resolution of the subdural hematomas within five postoperative months.

Discussion and conclusion

Discogenic microspurs can perforate the dura causing a CSF leak, leading to spontaneous intracranial hypotension, finally resulting in a bilateral subdural hematoma. This constellation of symptoms does not necessarily induce orthostatic headaches and can be treated with microsurgical duraplasty.

•

Discogenic microspur perforating the dura and inducing a liquor leak.

•

Discogenic microspur leading to spontaneous intracranial hypotension.

•

Discogenic microspur leading to bilateral subdural hematoma.

•

Liquor leak treated by microsurgical duraplasty.

•

Bilateral subdural hematoma retraction after microsurgical duraplasty.

Predictors of Early Neurological Improvement in Patients with Anterior Large Vessel Occlusion and Successful Reperfusion Following Endovascular Thrombectomy-Does CT Perfusion Imaging Matter?

PURPOSE

We aimed to investigate treatment effect of endovascular thrombectomy (EVT) on the change of National Institutes of Health Stroke Scale (NIHSS) scores in acute ischemic stroke (AIS) patients with anterior large vessel occlusion (LVO). Predictors of early neurological improvement (ENI) were assessed in those with successful reperfusion.

METHODS

Data on stroke patients from January 2018 to December 2020 were retrospectively analyzed. Anterior LVO was defined as occlusion of internal carotid artery and/or M1/M2 branch of middle cerebral artery. A reduction of at least 8 NIHSS points at 24 h after EVT or NIHSS score ≤ 1 at discharge was defined as ENI. In patients with successful reperfusion (TICI score of 2b/3) and available CT perfusion (CTP) imaging, 20 variables were tested in a smoothed ridge regression for their association with ENI.

RESULTS

One hundred seventy two out of 211 patients had successful perfusion with 54 patients achieving ENI. Impact of successful EVT on reducing NIHSS score grew continuously on a daily basis up to the date of discharge. 105 out of 172 patients were included in final regression model. Short time from onset to admission and from groin-puncture to reperfusion, young age, low prestroke disability, high baseline CTP ASPECTS and high follow-up non-contrast CT (NCCT) ASPECTS were significantly associated with ENI. Neither baseline NCCT ASPECTS nor the volume of penumbra or ischemic core measured on CTP were associated with ENI.

CONCLUSION

CTP ASPECTS might better predict ENI than non-contrast CT at baseline in patients with successful reperfusion following EVT.

Multimodality Characterization of the Clot in Acute Stroke

Aim: Current treatment of occluded cerebral vessels can be done by a variety of endovascular techniques. Sometimes, the clot responds in varying degrees to the treatment chosen. The Ex vivo characterization of the clot occluding the arteries in acute ischemic stroke can help in understanding the underlying imaging features obtained from pre-treatment brain scans. For this reason, we explored the potential of microCT when combined with electron microscopy for clot characterization. Results were compared to the clinical CT findings.

Methods: 16 patients (9 males, 8 females, age range 54–93 years) who were referred to our institution for acute stroke underwent dual-source CT.

Results: Clinical CT clots were seen as either iso or hyperdense. This was corroborated with micro-CT, and electron microscopy can show the detailed composition.

Conclusion: MicroCT values can be used as an indicator for red blood cells-rich composition of clots. Meaningful information regarding the clot composition and modalities of embedding along the stent retrievers can be obtained through a combination of microCT and electron microscopy.

Radiation Exposure During Diagnostic and Therapeutic Angiography of Carotid-cavernous Fistula : A Retrospective Single Center Observational Study

Purpose

The aim of this study was to determine local diagnostic reference levels (DRLs) during endovascular diagnostics and therapy of carotid-cavernous fistulas (CCF).

Methods

In a retrospective study design, DRLs, achievable dose (AD) and mean values were assessed for all patients with CCF undergoing diagnostic angiography (I) or embolization (II). All procedures were performed with the flat-panel angiography system Allura Xper (Philips Healthcare). Interventional procedures were differentiated according to the type of CCF and the type of procedure.

Results

In total, 86 neurointerventional procedures of 48 patients with CCF were executed between February 2010 and July 2021. The following DRLs, AD and mean values could be determined: (I) DRL 215 Gy ∙ cm², AD 169 Gy ∙ cm², mean 165 Gy ∙ cm²; (II) DRL 350 Gy ∙ cm², AD 226 Gy ∙ cm², mean 266 Gy ∙ cm². Dose levels of embolization were significantly higher compared to diagnostic angiography (p < 0.001). No significant dose difference was observed with respect to the type of fistula or the embolization method.

Conclusion

This article reports on diagnostic and therapeutic DRLs in the management of CCF that could serve as a benchmark for the national radiation protection authorities. Differentiation by fistula type or embolization method does not seem to be useful.

Multi-centric European post-market follow-up study of the Neuroform Atlas Stent System: primary results

BACKGROUND

Few prospective series have described the safety and effectiveness of the Neuroform Atlas Stent System. We aimed to investigate the efficacy and safety of the device in patients treated for unruptured aneurysm.

METHODS

ATLAS EU PMCF is a consecutive, prospective, multicentric study that included patients with unruptured saccular aneurysm of all sizes. Follow-up visits were scheduled at 3-6 months and 12-16 months with digital subtraction angiography (DSA) or MRI imaging follow-up as per the site standard of care. The primary efficacy endpoint was adequate aneurysm occlusion (Raymond Roy occlusion grade I and II) on 12 month angiography. The primary safety endpoint was any major stroke or ipsilateral stroke or neurological death within 12 months.

RESULTS

Of the 106 patients consented, 105 were treated with at least one Neuroform Atlas stent. There was a failed implantation attempt in 1 patient, 85 patients received lateral stenting, and 19 patients received Y-stenting. Mean aneurysm neck size was 4.2 mm (range 1.9-33 mm). Adequate occlusion was observed in 95.1% immediately after the procedure and in 98.9% of cases at 1 year DSA follow-up. Overall, 1.0% (1/102; 95% CI 0.0% to 5.3%) of patients experienced a primary safety endpoint of major stroke. Three minor strokes resulted in a modified Rankin Scale score of 2.

CONCLUSIONS

In this multicentric, prospective study, stent-assisted coiling of medium size unruptured aneurysms with the Neuroform Atlas stent resulted in a favorable rate of satisfactory occlusion. In our findings, the use of the Y-stenting technique was associated with increased rates of procedural complications.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02783339.

Therapy results of pericallosal aneurysms: A retrospective unicenter study

This retrospective study aims to compare treatment results of ruptured and unruptured pericallosal artery aneurysms (PAAs) regarding patient outcome and aneurysm recurrence after endovascular treatment (EVT) and neurosurgical treatment (NT). A total of 67 patients with PAA were admitted to our hospital, 44 patients with subarachnoidal hemorrhage (SAH) due to a ruptured PAA and 23 patients with unruptured PAA. The radiographic features of PAA were collected from pre-treatment digital subtraction angiography. In addition, demographic, clinical and radiographic parameters of all patients were recorded. Outcome was measured based on the modified Rankin scale (mRS) at 6 months after admission (favorable mRS score, 0-2 vs unfavorable mRS score, 3-6). Overall 46 patients underwent EVT and 21 patients NT. Six months after discharge 24 patients with SAH had a favorable outcome (mRS 0-2) and 16 patients an unfavorable outcome (mRS 3-6). Mortality rate of patients with SAH was 9.1% (4/44). Overall aneurysm recurrence was treated in 13 % of patients in the EVT cohort (6/46), whereas patients treated with NT had no recurrence. All patients with unruptured PAA had a favorable outcome. EVT and NT of PAA show comparable good results, although aneurysm recurrence occurs more often after EVT.

Is Histologic Thrombus Composition in Acute Stroke Linked to Stroke Etiology or to Interventional Parameters?

BACKGROUND AND PURPOSE

Detailed insight into the composition of thrombi retrieved from patients with ischemic stroke by mechanical thrombectomy might improve pathophysiologic understanding and therapy. Thus, this study searched for links between histologic thrombus composition and stroke subtypes and mechanical thrombectomy results.

MATERIALS AND METHODS

Thrombi from 85 patients who had undergone mechanical thrombectomy for acute ischemic stroke between December 2016 and March 2018 were studied retrospectively. Thrombi were examined histologically. Preinterventional imaging features, stroke subtypes, and interventional parameters were re-analyzed. Statistical analysis was performed with the Kruskal-Wallis test, Mann-Whitney U test, or Spearman correlation as appropriate.

RESULTS

Cardioembolic thrombi had a higher percentage of macrophages and a tendency toward more platelets than thrombi of large-artery atherosclerotic stenosis (P = .021 and .003) or the embolic stroke of undetermined source (P = .037 and .099) subtype. Thrombi prone to fragmentation required the combined use of contact aspiration and stent retrieval (P = .021) and were associated with an increased number of retrieving maneuvers (P = .001), longer procedural times (P = .001), and a higher lymphocyte content (P = .035).

CONCLUSIONS

We interpreted the higher macrophage and platelet content in cardioembolic thrombi compared with large-artery atherosclerotic stenosis or embolic stroke of undetermined source thrombi as an indication that the latter type might be derived from an atherosclerotic plaque rather than from an undetermined cardiac source. The extent of thrombus fragmentation was associated with a more challenging mechanical thrombectomy and a higher lymphocyte content of the thrombi. Thus, thrombus fragmentation not only might be caused by the recanalization procedure but also might be a feature of a lymphocyte-rich, difficult-to-retrieve subgroup of thrombi.

Effectiveness of Endovascular Recanalization Treatment for M2 Segment Occlusion: Comparison Between Intracranial ICA, M1, and M2 Segment Thrombectomy

RATIONALE AND OBJECTIVES

Mechanical thrombectomy is common practice in proximal anterior vessel occlusion. However, it remains unclear whether peripheral artery occlusions should be treated as well. This retrospective study aimed to prove the effectiveness of endovascular recanalization treatment for the M2 segment by comparison of intracranial internal carotid artery (ICA), M1 segment, and M2 segment thrombectomy.

MATERIALS AND METHODS

All patients who received endovascular treatment for distal ICA, M1, or M2 segment occlusions between January 2010 and July 2017 at our center were re-analyzed with respect to reperfusion success, interventional and clinical parameters. Statistical analysis was performed by Mann Whitney test, Chi square test, and Spearman correlation analysis.

RESULTS

A total of 261 patients (median age, 72 years), 100 with ICA, 137 with M1, and 24 with M2 segment occlusion, were included. Duration of endovascular treatment was significantly longer in ICA occlusions (median, 83 minutes, p < 0.001) compared to M1 (56 minutes) or M2 segment occlusions (49 minutes). Recanalization and reperfusion success and rate of endovascular complications did not differ between occlusion sites (AOL, p = 0.071; mTICI, p = 0.540; complications, p = 0.064). No significant difference in revascularization success was found between the different thrombectomy devices (direct thrombus aspiration, stent retrieving, or a sequential combined approach; p = 0.112). Successful M2 recanalization (mTICI 2b-3) correlated significantly with stronger posttherapeutic NIHSS reduction (r = 0.691, p < 0.001).

CONCLUSION

We found endovascular treatment of M2 segment occlusions as safe and successful as endovascular therapy of the ICA or M1 segment, with stronger posttherapeutic NIHSS reduction after successful compared to insufficient M2 recanalization.

Relative health-related quality of life after treatment of unruptured intracranial aneurysms: long-term outcomes and influencing factors

Health-related quality of life (HRQOL) is an important clinical outcome parameter. Its analysis is particularly meaningful to patients with minor functional impairment. The main goal of this study was to assess long-term data of HRQOL and their variables for patients undergoing treatment for unruptured intracranial aneurysms (UIAs). Therefore, a cross-sectional study of HRQOL (SF-36 questionnaire) was conducted in patients treated for UIA using a telephone survey assessing numerous medical and sociodemographic variables. A total of 96 patients with a follow up longer than 36 months post-treatment were included. HRQOL results were compared with the German reference population. Uni- and multivariate analyses were performed to detect variables with an impact on outcome. After a mean follow up of 57.75 ± 13.56 months, patients with treated UIAs showed a significant decrease in the mental health domains ‘role emotional’ and ‘social functioning’ and the ‘mental health component score’ (MHCS) compared with the age- and sex-matched reference population. Overall, 47% of the patients showed a clinically and psychosocially relevant decrease compared with the mean MHCS of the reference population. Multivariate analysis suggests that mainly the treatment modality (coiling versus clipping) and additional remaining untreated UIAs negatively impacted mental HRQOL. In conclusion, the partly significant losses in HRQOL identify the necessity for less-wearing treatment strategies and a better prediction of risk of UIA rupture. Our results indicate that certain factors in the guidance and management of patients undergoing endovascular treatment may negatively affect their mental HRQOL. The relevance of additional UIAs remaining untreated on HRQOL is a new finding that should be considered in the counseling of patients with multiple UIAs.

Stent-assisted treatment of ruptured intracranial aneurysms in the acute phase: A single center experience

Introduction

The purpose of this study was to analyze the results of patients with ruptured aneurysms who were treated with a specific microstent in the acute phase of subarachnoid hemorrhage.

Methods

Data from patients with acutely-ruptured intracranial aneurysm treated with the Neuroform stent in the period between 2003 and 2016 were retrospectively assessed, addressing aneurysm occlusion and clinical outcome with a focus on periprocedural complications.

Results

Twenty-nine consecutive patients with ruptured intracranial aneurysms were included in the analysis. Periprocedural hemorrhagic complications were stated in six patients, leading to death in four. Thromboembolic complications were observed in seven patients, among whom only one affected the clinical outcome with death due to basilar thrombosis. Immediate complete occlusion and occlusion with residual neck was achieved in 79.3% of cases.

Conclusion

Stent-assisted coiling of acutely-ruptured aneurysms achieves good immediate aneurysm occlusion. Rates of intra- and periprocedural adverse events observed in this series were significant, but did not translate to corresponding morbidity and mortality in all cases. The retrospective analysis did not allow assessing the overall risks of endovascular therapy with stent use in ruptured and complex aneurysm when compared to the overall risks with other alternative options.

•

SAC of acutely ruptured aneurysms achieves good immediate aneurysm occlusion.

•

Adverse events were frequent, but did not translate to morbidity and mortality in all cases.

•

SAC was only applied when alternative strategies would not be considered safe and sufficient.

Safety and effectiveness of large volume coils in the treatment of small aneurysms

BACKGROUND AND PURPOSE

Large volume soft design coils facilitate quicker aneurysm filling and high packing density. Our purpose was to analyze the feasibility, safety, and effectiveness of the Penumbra Coil 400 (PC400) system in the treatment of small aneurysms.

MATERIALS AND METHODS

A retrospective analysis of prospective data collected at three different centers was performed on consecutive aneurysms <10 mm treated with the PC400 system. A total of 92 aneurysms were included in the study. Feasibility, procedure safety, angiographic and clinical results, and follow-up results were evaluated.

RESULTS

Mean aneurysm size was 5.8±2.0 mm. An average of 2.5±1.3 coils with a mean length of 18±16 cm per aneurysm was used, resulting in a mean packing density of 45.6±14.4%. The thromboembolic event rate was 3.3% and no procedural aneurysm rupture was observed. Immediate adequate occlusion was achieved in 66% of aneurysms. During a mean follow-up period of 7.4 months the number of adequate occlusions increased to 91%.

CONCLUSIONS

Large volume PC 400 coils are safe and effective in the treatment of small aneurysms with a low thromboembolic complication rate and no hemorrhagic events. High packing densities are achieved with a low average number of coils used per aneurysm treated. The aneurysms demonstrated progressive occlusion over time, which probably suggests stability in the long term.

Associated Aneurysms in Infratentorial Arteriovenous Malformations: Role of Aneurysm Size and Comparison with Supratentorial Lesions

Background: The natural history and treatment of brain arteriovenous malformations (AVMs) is the object of ongoing debates and discussions. To capture the entirety of these complex lesions, associated vascular pathologies, such as associated aneurysms (AAs), have to be implemented in future risk stratification models, as they are believed to represent additional risk factors for intracranial hemorrhage. The present study aims to determine AA characteristics in posterior fossa AVMs and to compare with AAs accompanying supratentorial AVMs, with special focus on aneurysm size. Methods: Patients with cerebral AVMs, treated in our department between 1990 and 2013, were analyzed retrospectively. Only patients with flow-related AAs of the feeding arteries were evaluated. Thus, patients harboring intranidal, venous or remote aneurysms were excluded. Results: Of 485 patients with cerebral AVM, 76 patients harbored an AVM of the posterior fossa. Among those, 22 individuals exhibited a total of 35 AAs (n = 8 patients with multiple AAs). Most common location of AAs was the posterior inferior cerebellar artery (n = 20, 57%) and mean AA diameter was 7.9 mm (SD 5.5). In the subgroup of patients with a single AA, mean aneurysm size in posterior fossa AVMs was with 7.8 mm (SD 6.0; range 2-25 mm) significantly larger than the mean size of AAs with supratentorial AVMs (4.8 mm, SD 3.0; range 2-20 mm; p = 0.048). Intracranial hemorrhage was found in 18 of 22 patients (82%) with infratentorial AVMs, and of these, 11 patients suffered from aneurysm rupture. In 14 patients bearing a single AA, 8 (57%) had sustained hemorrhage from aneurysm rupture. The mean diameter of AAs was as supposed in the ruptured group with 9.8 mm (SD 6.9; range 4-25 mm) significantly larger than in the unruptured AA group exhibiting a mean of 5.0 mm (SD 3.3; range 2-10 mm; p = 0.038). Patients with posterior fossa AVMs and AAs were significantly older as compared to those patients with supratentorial lesions (57.1, SD 12.6 vs. 45.8 years, SD 15.9 years; p = 0.004), which was also evident in the subgroup of patients with single AAs (55.2, SD 11.7 vs. 45.8 years, SD 14.9 years; p = 0.038). Conclusions: AAs of posterior fossa AVMs are larger in diameter than aneurysms accompanying supratentorial AVMs. AA size influences risk for hemorrhage, which, together with the high number of hemorrhagic events in posterior fossa AVMs, justifies treating these pathologies. The higher age of patients with AVMs of the posterior fossa might be one reason for larger AAs in this cohort, when compared to patients with supratentorial AVMs and AAs.

The unruptured intracranial aneurysm treatment score: a multidisciplinary consensus

OBJECTIVE

We endeavored to develop an unruptured intracranial aneurysm (UIA) treatment score (UIATS) model that includes and quantifies key factors involved in clinical decision-making in the management of UIAs and to assess agreement for this model among specialists in UIA management and research.

METHODS

An international multidisciplinary (neurosurgery, neuroradiology, neurology, clinical epidemiology) group of 69 specialists was convened to develop and validate the UIATS model using a Delphi consensus. For internal (39 panel members involved in identification of relevant features) and external validation (30 independent external reviewers), 30 selected UIA cases were used to analyze agreement with UIATS management recommendations based on a 5-point Likert scale (5 indicating strong agreement). Interrater agreement (IRA) was assessed with standardized coefficients of dispersion (vr*) (vr* = 0 indicating excellent agreement and vr* = 1 indicating poor agreement).

RESULTS

The UIATS accounts for 29 key factors in UIA management. Agreement with UIATS (mean Likert scores) was 4.2 (95% confidence interval [CI] 4.1-4.3) per reviewer for both reviewer cohorts; agreement per case was 4.3 (95% CI 4.1-4.4) for panel members and 4.5 (95% CI 4.3-4.6) for external reviewers (p = 0.017). Mean Likert scores were 4.2 (95% CI 4.1-4.3) for interventional reviewers (n = 56) and 4.1 (95% CI 3.9-4.4) for noninterventional reviewers (n = 12) (p = 0.290). Overall IRA (vr*) for both cohorts was 0.026 (95% CI 0.019-0.033).

CONCLUSIONS

This novel UIA decision guidance study captures an excellent consensus among highly informed individuals on UIA management, irrespective of their underlying specialty. Clinicians can use the UIATS as a comprehensive mechanism for indicating how a large group of specialists might manage an individual patient with a UIA.

The Dural AV-Fistula (DAVF), the Most Frequent Acquired Vascular Malformation of the Central Nervous System (CNS)

Acquired arteriovenous malformations, such as is the case with dural arteriovenous fistulae (DAVF), are the consequence of a pathological new arterial ingrowth into venous spaces that reaches directly the venous lumen, without interposition of a capillary network, thereby creating an AV-shunt.The following concise text will provide elements in regards to diagnosis, indication for treatment discussion and choice of endovascular treatment (EVT) method.

Value of DSA in the diagnostic workup of pulsatile tinnitus

Objectives

Pulsatile tinnitus (PT) is a rare complaint, but can be a symptom of life-threatening disease. It is often caused by vascular pathologies, e.g. dural arteriovenous fistula (dAVF), arteriovenous malformation (AVM) or vascularized tumors. The current diagnostic pathway includes clinical examination, cranial MRI and additional DSA. The aim of this study was to evaluate the diagnostic impact of DSA in the diagnostic workup of patients with PT in comparison to MRI alone.

Methods

Retrospectively, 54 consecutive patients with pulsatile tinnitus were evaluated. All patients had a diagnostic workup including cranial MRI and DSA. MRI examinations were blinded to the results of DSA and retrospectively analyzed in consensus by two experienced neuroradiologists. The MR-examinations were evaluated for each performed sequence separately: time-of-flight-angiography, ce-MRA, T2, ce-T1-sequence and ce-T1-sequence with fat saturation.

Results

37 of the 54 patients revealed a pathology explaining PT on MRI, which was detected by the readers in 100% and proofed by means of DSA. 24 dAVF, four paraganglioma, two AVM and seven more pathologies were described. All patients without pathology on MRI did also not show any pathology in DSA.

Conclusions

MR imaging is sufficient to exclude pathology in patients with pulsatile tinnitus.

Associated Aneurysms in Supratentorial Arteriovenous Malformations: Impact of Aneurysm Size on Haemorrhage

Background: Associated aneurysms (AAs) are presumed to represent an additional risk factor for intracranial haemorrhage from cerebral arterio-venous malformations (AVMs). To date, efforts to capture their natural history, as well as to identify aneurysms with the potential capability of regression after AVM treatment remain incomprehensive. As the aneurysm size represents an important aspect for the treatment indication of incidental saccular aneurysms, this factor has rarely been encountered for the treatment of AAs so far. The present study aims to determine the angiographic and clinical characteristics of AAs with special focus on aneurysm size and their consequences for treatment. Methods: Patients with cerebral AVMs, treated in our department between 1990 and 2013, were analyzed retrospectively. Only patients with supratentorial AVMs and flow-related AAs of the feeding arteries were evaluated. Thus, patients harboring AVMs of the cerebellum and the brain stem and patients with intranidal, venous or remote aneurysms were excluded. Treatment strategies were assessed with special attention on bleeding source and on AA size. Results: In 59 of 409 patients (14%) with supratentorial AVMs, a total of 85 AAs of the feeding arteries were identified. 14 of 59 individuals (24%) presented with multiple AAs. Of 85 AA, 58 aneurysms (68%) were classified as proximal and 27 aneurysms (32%) as distal. The most common location of AAs was the middle cerebral artery (MCA, 39%), followed by the internal carotid artery (ICA, 27%) and the anterior cerebral artery (ACA, 21%). The mean AA size was 4.4 mm ± 3.4 mm. Intracranial haemorrhage was found in 21 of 59 patients (36%) with coexisting AAs. Among these, 10 individuals (17%) suffered from rupture of an AA, accounting for nearly half of all bleedings in this subgroup. Among those patients bearing a single AA, the size of ruptured aneurysms differed significantly from those unruptured (6.6 mm vs. 4.4 mm, p = 0.0046). Nineteen patients (32%) received treatment of 22 AAs, whereas sole AVM treatment was adopted in 26 patients (44%) and conservative management in 14 patients (24%). The main reasons to leave AAs untreated were the small AA size (<5 mm), poor clinical state or treatment denial by the patients. Conclusions: The aneurysm size of AAs in AVM influences the risk of haemorrhage. Therefore, the treatment of larger (diameter ≥5 mm) AAs should be considered, even if a treatment indication of the associated AVM is not given.

Treatment of complex neurovascular lesions: an interdisciplinary angio suite approach

OBJECTIVE

The objective of this study was to analyse our initial experience using an interdisciplinary angio suite approach to neurosurgical treatment of complex neurovascular lesions and expound technical feasibility and possible applications.

SUBJECTS

Six out of 451 patients with cranial or spinal neurovascular lesions were surgically treated in the angio suite (biplane angiographic system) during a 28-month observation period. Clinical baseline data, radiological and intraoperative findings as well as clinical and radiological outcome were assessed.

RESULTS

A ventral spinal perimedullary arteriovenous malformation, a ventral spinal perimedullary fistula, two diffuse frontal dural arteriovenous fistulas, a multifocal temporal arteriovenous malformation and a partially embolized fronto-temporo-basal dural arteriovenous fistula were successfully treated with angiographically confirmed complete occlusion and unimpaired neurological condition of the patients at the 12-month follow up.

CONCLUSION

This study demonstrates the feasibility of this approach and points out possible indications, namely ventrally located spinal lesions and diffuse, deep seated cranial lesions.

Silent embolism after stent-assisted coiling of cerebral aneurysms: diffusion-weighted MRI study of 75 cases

PURPOSE

New ischemic brain lesions are common findings after cerebral diagnostic angiography and endovascular therapy. Diffusion-weighted MRI (DWI) can be used for detection of these lesions. The aim of the present study was to investigate the incidence of DWI lesions after stent-assisted coiling and the evaluation of possible risk factors.

METHODS

The study included a total of 75 consecutive patients treated with stent-assisted coiling. Post-procedural DWI of the brain was performed to detect ischemic lesions. Demographic data, aneurysm characteristics and angiographic parameters were correlated with properties of DWI lesions.

RESULTS

In post-procedural DWI, 48 of the 75 patients (64%) had 163 DWI lesions in a pattern consistent with embolic events. The number of patients with DWI lesions was significantly increased in older patients (≥55 years) and longer intervention times (≥120 min). The ischemic brain volume was significantly increased in older patients (≥55 years) as well as in patients who were implanted with a shorter stent (<20 mm).

CONCLUSIONS

Thromboembolic events are common after stent-assisted coiling with an incidence comparable to DWI studies after coiling alone. Despite several devices and low operator experience, stent-assisted coiling for intracranial aneurysms has a very low risk of permanent neurologic disability. Further studies are necessary to improve the safety of stent-assisted coiling for patients in conditions with increased risk potential (age, procedure time, stent length).

A new-generation, low-permeability flow diverting device for treatment of saccular aneurysms

OBJECTIVES

We report a preclinical comparative study of a 96-strand braided flow diverter.

METHODS

The 96-strand braided device was compared with the currently commercially available flow diverter with 48 strands. The devices were implanted across the neck of 12 elastase-induced aneurysms in New Zealand White rabbits and followed for 1 and 3 months (n = 6 respectively). Aneurysm occlusion rates, parent artery stenosis and patency of jailed branch occlusions were assessed by angiography, histology and scanning electron microscopy studies.

RESULTS

It was feasible to navigate and implant the 96-strand device over the aneurysm orifice in all cases. At follow-up two aneurysms in the 48-strand vs. one in the 96-strand group were not occluded. This aneurysm from the 96-strand group however had a tracheal branch arising from the sac and showed a reverse remodelling of the vascular pouch at 3 months. In the occluded aneurysms, the parent artery was always completely reconstructed and the aneurysm orifice was sealed with neointimal tissue. No in-stent stenosis or jailed branch artery occlusion was observed.

CONCLUSIONS

The 96-strand flow diverter proved to be safe, biocompatible and haemodynamically effective, induced stable occlusion of aneurysms and led to reverse remodelling of the parent artery.

KEY POINTS

• Flow diversion has been introduced to improve endovascular treatment of cerebral aneurysms • A new low-permeability flow diverter is feasible for parent artery reconstruction. • The Silk 96 flow diverter appears effective at inducing aneurysm healing. • The covered branches remained patent at follow-up.

Intramedullary spinal cord astrocytomas: the influence of localization and tumor extension on resectability and functional outcome

BACKGROUND

Intramedullary spinal cord tumors (IMSCT) are rare lesions, ependymomas and astrocytomas being the most common ones. Different studies have been published showing results of different treatment strategies as extensive/ limited surgery, biopsy and adjuvant radiation therapy with regard to functional outcome and survival. The present study was undertaken to analyse our series of surgically treated intramedullary astrocytomas in order to identify factors with impact on functional outcome and resectability.

METHODS

Over a period of 20 years, among 215 patients with IMSCT 22 patients with astrocytomas were identified and enrolled into this analysis. Demographic data, clinical symptoms, localization and extension of the tumor, resection rate as well as pre- and postoperative neurological status were obtained. Patients were followed-up clinically and by MRI.

RESULTS

Complete resection rate was higher in cervically located tumors (9 of 10) compared to non-cervical tumors (7 of 12). Tumor extension (1-3 segments vs. > 3 segments involved) did not influence on the resection rate. Cervical tumors showed a trend for better postoperative functional outcome than non-cervical lesions (3 of 10 cervical but 6 of 12 non-cervical tumors deteriorated postoperatively). In tumors extending more than 3 segments postoperative worsening was significantly increased.

CONCLUSIONS

The present study shows a better resectability and functional outcome for cervically located intramedullary astrocytomas. Tumors extending more than three segments deteriorated significantly. These findings may help for decision-making process and treatment of these tumors.

Association of aneurysms and variation of the A1 segment

BACKGROUND AND PURPOSE

Previous studies have described a correlation between variants of the circle of Willis and pathological findings, such as cerebrovascular diseases. Moreover, anatomic variations of the anterior cerebral artery (ACA) seem to correspond to the prevalence of aneurysms in the anterior communicating artery (ACoA). The aim of this study was to assess the prevalence of aneurysms in patients with anatomical/morphological variations of the circle of Willis.

METHODS

We retrospectively analyzed 223 patients who underwent cerebral angiography between January 2002 and December 2010 for aneurysm of the ACoA. Diagnostic imaging was reviewed and statistically evaluated to detect circle of Willis anomalies, aneurysm size, and rupture. 204 patients with an unrelated diagnosis served as the control group.

RESULTS

Variations of the A1 segment occurred significantly more frequently in the aneurysm group than in the control group. Mean aneurysm size in patients with grades I and III hypoplasia or aplasia was 6.58 mm whereas in patients with grade II hypoplasia it was 7.76 mm.

CONCLUSIONS

We found that variations in the A1 segment of the ACAs are correlated with a higher prevalence of ACoA aneurysms compared with patients with a symmetric circle of Willis.

[3-year follow-up after endovascular aneurysm treatment with Silk® flow diverter]

PURPOSE

Flow diverters may occlude aneurysms by endoluminal reconstruction of the parent artery and by reducing the blood flow into the aneurysm. The purpose of this study was to assess the rate of intervention-associated complications and a 3-year-follow-up.

MATERIALS AND METHODS

We retrospectively analyzed 18 patients treated with Silk® FD. Only patients with unruptured aneurysms were included. Treatment indications were fusiform, giant or recurrent aneurysms. We considered all aneurysms to have a high likelihood of failure and/or recurrence when treated with conventional endovascular techniques.

RESULTS

Silk FD could directly be placed in a proper position across the whole length of the aneurysm in 16/18 patients. In one case an additional PTA was necessary. In another case the first FD could not be properly deployed. 17 of 18 aneurysms (95 %) were occluded immediately, in the mid-term follow-up after 6 months or 3 years after treatment. The overall complication rate including technical (11.1 %), acute or delayed thromboembolic complication without (11.1 %) or with (16.6 %) severe complications was documented.

CONCLUSION

FD treatment is effective with a high occlusion rate of aneurysms also in long-term follow-up. In these complex aneurysms the complication rate is higher than in conventional stent-assisted coiling.

Neuroform stent-assisted treatment of intracranial aneurysms: long-term follow-up study of aneurysm recurrence and in-stent stenosis rates

INTRODUCTION

Our purpose was to analyze the long-term evolution of wide neck cerebral aneurysms treated with stent assistance.

METHODS

Data of consecutive patients treated with the Neuroform stent over 9 years were retrospectively analyzed with emphasis on periprocedural complications, aneurysm occlusion grade evolution, and in-stent stenosis rates.

RESULTS

Altogether, 113 patients with 117 unruptured and ruptured aneurysms were subject of analysis. Mean aneurysm size was 9.4 mm, and mean neck size was 4.7 mm. Procedural thromboembolic and hemorrhagic complications affected eight (6.8%) and four cases (3.4%), respectively. Immediate complete occlusion and occlusion with residual neck was achieved in 85% of cases, which at the first follow-up of 6 months, changed to 77 and 76 % at 36 months. Aneurysms ≥10 mm showed a higher tendency of recurrence. During the overall follow-up time ranging from 1 to 9 years, an in-stent stenosis of ≥50 % was observed only in three cases, all of them being asymptomatic.

CONCLUSIONS

Stent-assisted coiling of wide neck aneurysms provided stable occlusion over the long-term follow-up, with very low and silent in-stent stenosis rates. Some incompletely occluded aneurysms showed a tendency of progressive occlusion; however, this was counterbalanced by the regrowth of others.

Randomised trial of clazosentan, an endothelin receptor antagonist, in patients with aneurysmal subarachnoid hemorrhage undergoing surgical clipping (CONSCIOUS-2)

We report here results of a randomized, double-blind, placebo-controlled study ( http://www.ClinicalTrials.gov , NCT00558311) that investigated the effect of clazosentan (5 mg/h, n = 768) or placebo (n = 389) administered for up to 14 days in patients with aneurysmal subarachnoid hemorrhage (SAH) repaired by surgical clipping. The primary endpoint was a composite of all-cause mortality, new cerebral infarction or delayed ischemic neurological deficit due to vasospasm, and rescue therapy for vasospasm. The main secondary endpoint was the Glasgow Outcome Scale Extended (GOSE), which was dichotomized. Twenty-one percent of clazosentan- compared to 25% of placebo-treated patients met the primary endpoint (relative risk reduction [RRR] [95% CI]: 17% [-4% to 33%]; p = 0.10). Poor outcome (GOSE score ≤ 4) occurred in 29% of clazosentan- and 25% of placebo-treated patients (RRR: -18% [-45% to 4%]; p = 0.10). In prespecified subgroups, mortality/vasospasm-related morbidity was reduced in clazosentan-treated patients by 33% (8-51%) in poor WFNS (World Federation of Neurological Surgeons) grade (≥III) and 25% (5-41%) in patients with diffuse, thick SAH. Lung complications, anemia and hypotension occurred more frequently with clazosentan. Mortality (week 12) was 6% in both groups. The results showed that clazosentan nonsignificantly decreased mortality/vasospasm-related morbidity and nonsignificantly increased poor functional outcome in patients with aneurysmal SAH undergoing surgical clipping.

Flow diversion treatment: intra-aneurismal blood flow velocity and WSS reduction are parameters to predict aneurysm thrombosis

BACKGROUND

To evaluate the haemodynamic changes induced by flow diversion treatment in cerebral aneurysms, resulting in thrombosis or persisting aneurysm patency over time.

METHOD

Eight patients with aneurysms at the para-ophthalmic segment of the internal carotid artery were treated by flow diversion only. The clinical follow-up ranged between 6 days and 12 months. Computational fluid dynamics (CFD) analysis of pre- and post-treatment conditions was performed in all cases. True geometric models of the flow diverter were created and placed over the neck of the aneurysms by using a virtual stent-deployment technique, and the device was simulated as a true physical barrier. Pre- and post-treatment haemodynamics were compared, including mean and maximal velocities, wall-shear stress (WSS) and intra-aneurysmal flow patterns. The CFD study results were then correlated to angiographic follow-up studies.

RESULTS

Mean intra-aneurysmal flow velocities and WSS were significantly reduced in all aneurysms. Changes in flow patterns were recorded in only one case. Seven of eight aneurysms showed complete occlusion during the follow-up. One aneurysm remaining patent after 1 year showed no change in flow patterns. One aneurysm rupturing 5 days after treatment showed also no change in flow pattern, and no change in the maximal inflow velocity.

CONCLUSIONS

Relative flow velocity and WSS reduction in and of itself may result in aneurysm thrombosis in the majority of cases. Flow reductions under aneurysm-specific thresholds may, however, be the reason why some aneurysms remain completely or partially patent after flow diversion.