Intracranial Arterial Aneurysms Research Articles

Flow diverter for endovascular treatment of intracranial mirror segment internal carotid artery aneurysms.

To evaluate the feasibility and efficacy of the pipeline embolization device in the treatment of unruptured intracranial mirror segment aneurysms. Out of a total of 338 subjects, 14 were identified harboring a total of 32 internal carotid artery mirror segment aneurysms that were treated with the pipeline embolization device and were consecutively enrolled into our study. We collected data on patient demographics, modified Rankin scale (mRS) at admission, aneurysm characteristics, clinical outcome at discharge, 3-9 and at 12-18 months as well as angiography results at follow-up. Patients' mean age was 52.9 years; baseline mRS was 0 in all subjects. Pipeline embolization device placement was successful in all cases. Post-treatment mRS remained 0 in 13/14 patients. One patient experienced a small intraparenchymal hemorrhage and subarachnoid hemorrhage, associated with a frontoparietal infarction resulting in right upper extremity weakness and aphasia (post-treatment mRS 3). His mRS evaluation remained stable at the 3-9-month follow-up. Three to 9-month follow-up angiography (13/14 subjects) showed complete aneurysm occlusion in 24/30 aneurysms (80%), near complete and partial occlusion in three of 30 (10%) aneurysms each. At the 9-month follow-up, one patient experienced a complete occlusion of the anterior temporal artery branch but did not present with any clinical deficits. No mRS changes were encountered over a median 6-month follow-up period. Mid-term follow-up angiography (12-18 months) available in eight of 14 subjects showed complete aneurysm occlusion in all patients. Mild intimal hyperplasia was observed in one patient. Flow diversion technology can be used for the treatment of unruptured mirror segment aneurysms in selected patients.

P6042Association of intracranial arterial aneurysms and thoracic aortic aneurysms and dilatation

P6042Association of intracranial arterial aneurysms and thoracic aortic aneurysms and dilatation

Transient in-stent stenosis: a common finding after flow diverter implantation

Background and purposeIn recent years, implantation of flow diverters has emerged as an option for the endovascular treatment of intracranial aneurysms. One complication of treatment with flow diverters is the...

Pediatric intracranial distal arterial aneurysms: report of 35 cases.

Although research on pediatric intracranial aneurysms is well documented, studies of pediatric intracranial distal arterial aneurysms (PIDAAs) remain scarce. All pediatric patients (≤ 18years) with intracranial aneurysms located distally to the M2 segment of the middle cerebral artery (MCA), A2 segment of the anterior cerebral artery, P2 segment of the posterior cerebral artery, and other cerebral arteries distal to the main branch who were treated at our center between January 2012 and April 2017 were retrospectively reviewed. Thirty-five PIDAAs were observed in 35 patients with a mean age of 9.2 ± 5.9years and a male ratio of 71.4% (n = 25). Sudden onset of severe headache was the most common symptom (n = 22, 62.9%), followed by seizures (n = 21, 60%). Twenty-seven patients (77.1%) had ruptured aneurysms, and 18 of them (66.7%) exhibited combined lobe intracerebral hematoma. MCA was the most common site (n = 23, 65.7%). Large or giant aneurysms were observed in 16 patients (45.7%). Eight patients (22.9%) had pseudoaneurysms, six of whom (75%) reported a head trauma history. Thirty patients (85.7%) had favorable outcomes at the end of the 6-month follow-up. Kaplan-Meier 6-month seizure curves revealed a significantly higher decrease in seizure rates in the surgical group than in the endovascular group (P = 0.036). PIDAAs constitute a high proportion of pediatric intracranial aneurysms. PIDAAs are associated with an increased risk of seizures, a predilection for the MCA, and a high incidence of pseudoaneurysms with head trauma history. Surgical intervention is of greater benefit than endovascular treatment in controlling the risk of seizures.

High-resolution cone beam CT for evaluation of vascular channel in intracranial partial thrombosed aneurysm.

ABSTRACTThe authors present a 60-year-old man with a partially thrombosed, intracranial vertebral artery aneurysm. A vascular channel in intra-aneurysmal thrombus was effectively identified with high-resolution cone beam CT (DynaCT Micro: Siemens Medical Solutions, Erlangen, Germany). Pre-procedural vertebral angiogram implied a perforating artery arising from near neck of the aneurysm and DynaCT Micro performed before approaching to the lesion demonstrated a vascular channel running in intra-aneurysmal thrombus which could not be distinguished from perforators with other imaging modalities. It was confirmed that perforators around the aneurysm were not identified and safely treated the aneurysm with stent-assisted coil embolization. High-resolution cone beam CT is enable to sharply visualize vessel lumens, thrombus, and intra-thrombus structures, and is useful to identify a vascular channel in intracranial partially thrombosed aneurysm.

A New Approach for Photorealistic Visualization of Rendered Computed TomographyImages.

Classical single-colored or multicolored 3-dimensional (3D) visualization of sectional images lacked in being realistic and revealed limited anatomical discrimination. Recently, a new technique called cinematic volume rendering for 3D reconstruction of computed tomography has been developed. The aim of this study was to analyze this new visualization algorithm from a technical perspective and to investigate potential benefits for neurosurgical applications. A standard test in computer graphics called Cornell Box was adapted and applied for reproducibility of light effects in cinematic rendering opposed to classic rendering methods. Simulation of distinct camera effects such as variable apertures, exposition time, optics, and surface refinements are presented in a human skull, respectively. Postprocessing capabilities allow for immediate clinical use. This volume-rendering technique generates cadaver-like 3D reconstructions. By considering complex interactions between a scanned object and dynamic light patterns, a cinematic illumination of a 3D surface reconstruction can be achieved. A spinal tumor case and a complex intracranial carotid artery aneurysm are presented, comparing all available rendering techniques. Cinematic rendering results in greater spatial discrimination of neighboring anatomical structures. This technical and clinical description focuses on the neurosurgical relevance of a new rendering technique. Considering the improved image impression of cinematic rendering and viewers' perception, it seems likely that the technique will gain wide acceptance in the clinical routine.

Three-dimensional intracranial middle cerebral artery aneurysm models for aneurysm surgery and training

To develop a realistic model of middle cerebral artery (MCA) aneurysms using three-dimensional (3D) printing for surgical planning, research, and training of neurosurgical residents. This study included eight MCA aneurysm cases. The aneurysm together with the adjacent arteries and skull base were printed based on raw computed tomography angiography (CTA) data using a 3D printer with acrylonitrile-butadiene-styrene as the model material. The aneurysm models were used for surgical planning, and craniotomy and clipping practice by neurosurgical residents. Feedback was obtained using a survey. 3D aneurysm models were created for all seven MCA aneurysm patients. There was good agreement in the model aneurysm diameter, width, and neck and the CTA data, with no significant difference (p > 0.05) among the groups. The simulator was useful for choosing the clips to use before surgery. The average response to each of the survey questions was greater than 3.85 (range 3.0–5.0) on a five-point scale. The 3D printed MCA aneurysm models were accurate. Simulation and practice using the 3D models was useful for understanding the aneurysm structure and choosing the clips to use before surgery, especially for junior neurosurgeons.

Abstract WMP33: Real-World Clinical Outcomes of Ruptured Intracranial Arterial Aneurysm Treatment

Introduction: Comparison of real world clinical outcomes between clipping and coiling for ruptured aneurysm is challenging, mainly due to confounding case severity and variation in physician expertise. We sought to compare outcomes and costs of coiling and clipping by utilizing a large national database. Methods: Ruptured intracranial aneurysm patients age 18 to 86 years were identified from the National Inpatient Sample (NIS) from 2007 to 2013. The clinical outcomes evaluated were in-hospital mortality, in-hospital stroke, discharge destination and other complications. Also, the total hospitalization cost was compared. Multivariate logistic regression and propensity-score matching were used. Confounding factors such as specific neurovascular comorbidities (e.g. hypertension, diabetes), Charleson comorbidity index (CCI), all patient refined diagnosis related group (APR-DRG) risk of mortality, APR-DRG severity index, and NIS-SAH severity score were also controlled for. Results: 14379 patients with ruptured intracranial arterial aneurysms were identified (5966 clipping, 8413 coiling). Univariate analysis showed that coiling patients had higher preprocedural risks by CCI (p < 0.001) and APR-DRG mortality (p<0.001). Multivariate analysis showed no difference in in-house mortality (OR 0.96, p = 0.60), but coiling showed lower in-house strokes (OR 0.67, p < 0.001) and more discharge to a rehabilitation facility (OR 0.63, p<0.001). Coiling patients had higher odds of a hematoma (OR 1.44, p = 0.09) and hydrocephalus requiring treatment (OR 1.55, p<0.01), but lower odds of requiring a blood transfusion (OR 0.52, p<0.01). Analysis over time showed that in-house mortality has decreased over time (p=0.01) in coiling patients, but mortality after clipping has not changed. Coiling was slightly more expensive, but the difference was not significant ($2267, p=0.13). Conclusions: After adjusting for severity, there was no significant difference in mortality between coiling and clipping in ruptured aneurysm treatment. However, coiling patients had a lower chance of an in-hospital stroke and a higher chance of being discharged home. A limitation of the study is the possibility of unmeasured confounders.

Cerebral vascular syndrome of connective tissue dysplasia as a cause of subarachnoid hemorrhage in young patients

To clarify the role of connective tissue dysplasia (CTD) in the development and course of intracranial arterial aneurysm (IAA) and arteriovenous malformation (AVM) in young patients. The first stage of the study was a prospective 7-year follow-up of 549 patients with CDT signs, aged from 18 to 45 years, mean 23.51±8.67 years. The first stage included a comparative analysis of clinical characteristics of patients with DST with asymptomatic pathology of cerebral vessels and patients with DST without this pathology. At the second stage, there was a comparative study in 2 groups of patients with symptomatic pathology of cerebral vessels (AAA and/or AVM): with CTD (n=58) and without CTD (n=135). Symptomatic AAA and/or AVM were identified in 10.56% of young people with CTD including 37 patients with subarachnoid hemorrhages (SAH). The age of clinical manifestations was 25.55±8.13 years. Expressed manifestations of CTD were more frequent in the group of patients with cerebral vascular pathology compared to patients without CTD (p=0.008). The majority of patients had CTD manifestations of 3 or more systems, less than 2 systems were not involved, 12 patients had small abnormalities and/or malformations of the heart and other vessels. Hypertension, pathology of the vertebral arteries, skin, spine, veins, fully open Willis circle were independent risk factors for symptomatic pathology of cerebral vessels in patients with CTD. AVM and AAA in young patients with CTD compared with patients without CTD were characterized by the manifestation at an earlier age (25.55±8.13 years and 36.10±10.58 years, respectively; p=0.000), a more frequent combination with a fully open Willis circle (56.90 and 25.19%, respectively; df=1; p=0.000), more frequent multiple pathologies (15.52 and 4.44%, respectively, p=0.008), EAA in the posterior vascular bed (15.52 and 3.70%, respectively, p=0.004), SAH (63.79 and 35.56%, respectively, p=0.000) with lesser effects of general population risk factors. EAA and AVM in patients with CTD are likely to be considered in the context of vascular syndrome of connective tissue dysmorphogenesis, and CTD as a factor of adverse prognosis of IAA and AVM.

L’HyDROCEPHALIE POST HEMORRAGIE SOUS ARACHNOÏDIENNE PAR RUPTURE D’ANEVRySME : INCIDENCE, PRISE EN CHARGE ET RESULTATS THERAPEUTIQUES A PARTIR D’UNE SERIE RETROSPECTIVE DE 51 PATIENTS

SHA by ruptured aneurysm is a serious condition, burdened with a significant morbidity and mortality. Hydrocephalus is a common complication of SAH. The indication of the external ventricular draining for acute hydrocephalus is well codified. On the other hand, that of chronic ventricular dilatations is still controversial despite the large number of series seeking to identify modifiable predictive factors for shunt dependency. We conducted a 12-month retrospective study to assess the incidence, profile and therapeutic outcomes of hydrocephalus following SAH. Patients and Methods: This was a retrospective study based on the use of records of patients hospitalized in the Clermont-Ferrand Hospital and having had SAH by ruptured intracranial arterial aneurysm during the period from 1 January 2012 to 31 December 2012 .We excluded SAH from other origins and patients who died before the 48th hour. General datas such as age, sex, duration of hospitalization were evaluated. The WFNS, Fisher and Rankin classifications were used to assess respectively clinical status, CT scan results and patients outcomes. Results: We collected 51 cases of sub-arachnoid haemorrhage by rupture of aneurysm, 21 patients developed acute hydrocephalus, treated with EVD . Of these patients, 7 developed a chronic hydrocephalus treated by permanent shunt (overall incidence of 13.72%). There were 39 women and 12 men. The mean age of the series was 54.4 years ranging from 27 to 81 years. The mean age of patients needing permanent shunt was 68.85 years. The WFNS classification found 20 cases of grade 1 and 15 cases grade 2 . Twenty-four patients were Fisher 2 and 20 Fisher 4. The mean caudate index measured in patients treated for chronic hydrocephalus was 0.43 ranging between 0.40 and 0.47. Twenty-one patients underwent an external ventricular draining, 15 on the day of bleeding, 5 patients had drain after 24 hours. One patient had his EVD on day 6. The treatment of ruptured aneurysm was endovascular in 44 patients and surgical in 6 patients. One patient had no treatment for his aneurysm. A permanent internal CSF derivation was performed in 7 patients and was a ventriculo-peritoneal shunt in all cases. The outcomes of the survivors by the modified Rankin scale found 72% of good outcomes and 28 % of patients had poor outcomes. Conclusion: The incidence of hydrocephalus after SAH is broadly comparable with the results of the literature. External ventricular drainage is well codified with few complications. A series with a larger size could make it possible to look for predictive factors of shunt dependency. Key words: subarachnoid haemorrhage, hydrocephalus, ventriculoperitoneal shunt

Association between polymorphism of SMAD3 gene and risk of sporadic intracranial arterial aneurysms in the Chinese Han population

Intracranial arterial aneurysms (IAAs) are locally abnormal dilations of the cerebral arteries and often result in subarachnoid hemorrhages (SAH). Genetic, molecular and cellular mechanisms of sporadic IAAs forms are poorly understood. In this study, we investigate the association between mothers against decapentaplegic homolog 3 (SMAD3) genotypes and the risk of sporadic intracranial arterial aneurysms among the Chinese Han population. A case-control study was conducted examining 330 IAA patients and 313 controls. There were eight single nucleotide polymorphisms of SMAD3 selected and genotyped using the polymerase chain reaction-ligase detection reaction (PCR-LDR) method. Our results indicated that SMAD3 rs1065080 polymorphism was associated with a risk of IAAs in a codominant model (GA vs GG, OR=1.433; 95% CI 1.030–1.994; P=0.032). In summary, we observed that SMAD3 rs1065080 single nucleotide gene polymorphisms were significantly associated with patient susceptibility to IAAs.

Predicting symptomatic cerebral vasospasm after aneurysmal subarachnoid hemorrhage with an artificial neural network in a pediatric population.

Artificial neural networks (ANN) are increasingly applied to complex medical problem solving algorithms because their outcome prediction performance is superior to existing multiple regression models. ANN can successfully identify symptomatic cerebral vasospasm (SCV) in adults presenting after aneurysmal subarachnoid hemorrhage (aSAH). Although SCV is unusual in children with aSAH, the clinical consequences are severe. Consequently, reliable tools to predict patients at greatest risk for SCV may have significant value. We applied ANN modeling to a consecutive cohort of pediatric aSAH cases to assess its ability to predict SCV. A retrospective chart review was conducted to identify patients <21years of age who presented with spontaneously ruptured, non-traumatic, non-mycotic, non-flow-related intracranial arterial aneurysms to our institution between January 2002 and January 2015. Demographics, clinical, radiographic, and outcome data were analyzed using an adapted ANN model using learned value nodes from the adult aneurysmal SAH dataset previously reported. The strength of the ANN prediction was measured between -1 and 1 with -1 representing no likelihood of SCV and 1 representing high likelihood of SCV. Sixteen patients met study inclusion criteria. The median age for aSAH patients was 15years. Ten underwent surgical clipping and 6 underwent endovascular coiling for definitive treatment. One patient experienced SCV and 15 did not. The ANN applied here was able to accurately predict all 16 outcomes. The mean strength of prediction for those who did not exhibit SCV was -0.86. The strength for the one patient who did exhibit SCV was 0.93. Adult-derived aneurysmal SAH value nodes can be applied to a simple AAN model to accurately predict SCV in children presenting with aSAH. Further work is needed to determine if ANN models can prospectively predict SCV in the pediatric aSAH population in toto; adapted to include mycotic, traumatic, and flow-related origins as well.

Prevalence of Intracranial Aneurysm in Women With Fibromuscular Dysplasia

The prevalence of intracranial aneurysm in patients with fibromuscular dysplasia (FMD) is uncertain. To examine the prevalence of intracranial aneurysm in women diagnosed with FMD. This cross-sectional study included 669 women with intracranial imaging registered in the US Registry for Fibromuscular Dysplasia, an observational disease-based registry of patients with FMD confirmed by vascular imaging and currently enrolling at 14 participating US academic centers. Registry enrollment began in 2008, and data were abstracted in September 2015. Patients younger than 18 years at the time of FMD diagnosis were excluded. Imaging reports of all patients with reported internal carotid, vertebral, or suspected intracranial artery aneurysms were reviewed. Only saccular or broad-based aneurysms 2 mm or larger in greatest dimension were included. Extradural aneurysms in the internal carotid artery were included; fusiform aneurysms, infundibulae, and vascular segments with uncertainty were excluded. Percentage of women with FMD with intracranial imaging who had an intracranial aneurysm. Of 1112 female patients in the registry, 669 (60.2%) had undergone intracranial imaging at the time of enrollment (mean [SD] age at enrollment, 55.6 [10.9] years). Of the 669 patients included in the analysis, 86 (12.9%; 95% CI, 10.3%-15.9%) had at least 1 intracranial aneurysm. Of these 86 patients, 25 (53.8%) had more than 1 intracranial aneurysm. Intracranial aneurysms 5 mm or larger occurred in 32 of 74 patients (43.2%), and 24 of 128 intracranial aneurysms (18.8%) were in the posterior communicating or posterior arteries. The presence of intracranial aneurysm did not vary with location of extracranial FMD involvement. A history of smoking was significantly associated with intracranial aneurysm: 42 of 78 patients with intracranial aneurysm (53.8%) had a smoking history vs 163 of 564 patients without intracranial aneurysm (28.9%; P < .001). The prevalence of intracranial aneurysm in women diagnosed with FMD is significantly higher than reported in the general population. Although the clinical benefit of screening for intracranial aneurysm in patients with FMD has yet to be proven, these data lend support to the recommendation that all patients with FMD undergo intracranial imaging if not already performed.

Brain MRI Findings and Neuro-Psychiatric Involvement in Paroxysmal Nocturnal Hemoglobinuria (PNH)

▪PNH is a rare disorder characterized by hemolytic anemia, marrow failure and thrombosis, due to a deficiency in GPI-anchored proteins. Thrombotic events in PNH are commonly described in hepatic, portal, mesenteric, splenic, and renal veins, along with anecdotic case reports of cerebral venous sinus thrombosis and arterial ischemic strokes.This study was aimed at investigate brain involvement in 19 asymptomatic PNH patients by non-enhanced cerebral magnetic resonance imaging (MRI), and by intracranial arterial and venous angio-MRI. Neuroradiological findings were completed with a neuro-psychiatric evaluation, and correlated with clinical/hematologic features and therapy.Seventeen out of 19 patients were classical hemolytic (63% transfusion dependent before treatment with eculizumab and 1 patient also after), and 2 PNH in the context of aplastic anemia (all transfusion-dependent until treatment with ATG-CyA). Median age at diagnosis was 44 years (range 17-80); asthenia and dyspnea on exertion were present in all patients, abdominal pain in 8, and a thrombotic event in 4. Median Hb was 9.6 g/dL (range 6.7-12.9), LDH 3.7-fold (range 1.2-16.3) over upper limit of normal (ULN), and 73% of patients displayed a clone size greater than 50% GPI negative cells; 10/19 of patients were on eculizumab at the moment of the study.On MRI, 11 subjects showed pathological findings: 9 cases displayed white matter (WM) abnormalities related to chronic ischemic small vessel disease, of whom 6 periventricular WM vascular degeneration, and 8 deep WM focal chronic ischemic lesions (5 cases have both sites involved). Moreover, 1 subject showed a focal abnormality >5 mm and 5 subjects a score > 4 as evaluated in WM and basal ganglia by the age related white matter changes (ARWMC) scale. No subject displayed active or previous bleeding, nor were focal alterations of the basal nuclei by the ARWMC scale found. Two patients (80 and 81 yrs) showed atrophy of the cerebral hemispheres. Regarding vascular abnormalities, one subject had hypoplastic left transverse sinus with irregularities in the sinus wall, suspected for prior partial venous thrombosis. Three further cases displayed hypoplastic transverse sinus associated with collateral draining cortical veins, indistinguishable from anatomical variants. Intracranial artery stenosis or aneurysm, and Moya-Moya like alterations were not observed. Finally, cerebral MRI was unremarkable in 8/19 subjects.By comparing patients with or without any MRI abnormality (WM and vascular alterations), mean age was significantly higher in the former (60+17 vs 43+8 yrs, mean+SD, p<0.05), whereas blood counts, hemolytic markers and clone size showed no remarkable differences. Hemoglobin at diagnosis was slightly lower (9.5+1.5 vs 9.9+1.6 g/dL, mean+SD), and LDH greater (5.8+4.4 vs 4.1+2.9 over ULN, mean+SD) in subjects who displayed MRI abnormalities. Moreover, individual hemoglobin levels negatively correlated with the ARWMC score (r=-0.45, p<0.05). No relationship was found between history of abdominal pain/thrombosis and MRI pathological findings. Likewise, MRI abnormalities were not correlated with disease duration. As regards therapy with eculizumab, a pathological MRI was found in 6/10 subjects under treatment and in 5/9 without; the sole significant vascular alteration was detected in a patient under treatment.Neurological examination was unremarkable in all patients but one, who complained of progressive rest tremor in his left arm and leg (twelve years after PNH diagnosis), and was diagnosed with possible Parkinson disease. Previous history of neurological disorders was observed in 3 patients: one typical transient global amnesia (at the age of 60), one seizures (at 5 years), and one headache before the diagnosis of PNH. Regarding psychiatric evaluation, 3/18 patients had a psychiatric disorder according to structured clinical interview for axis I DSM-IV-TR disorders (1 generalized anxiety disorder, 1 bipolar disorder type 2, and 1 adjustment disorder as a consequence of PNH diagnosis). No relationship was observed between MRI findings and neuro-psychiatric assessment.In conclusion, brain MRI revealed chronic ischemic and vascular lesions in 58% of asymptomatic PNH patients. Brain MRI is advisable at diagnosis and during the course of the disease, and WM lesion burden may be useful in the decision to start therapy. DisclosuresBarcellini:Agios: Consultancy.

Tailor-made shaping of microcatheters using three-dimensional printed vessel models for endovascular coil embolization

BackgroundStabilization of microcatheters during coiling after their optimal shaping are key factors for successful endovascular coil embolization of cerebral aneurysms. However, stabilization and optimal shaping of microcatheters are sometimes difficult. Our aim was to introduce “tailor-made” microcatheter shapes for coil embolization using three-dimensional (3D) printed vessel models. MethodSince August 2014, we have been investigating the use of 3D printed models of intracranial arterial aneurysms to produce optimally shaped microcatheters for endovascular coil embolization. Using Digital Imaging and Communication in Medicine data obtained from preoperative cerebral angiography, a vessel model was produced with a 3D printer using acrylic resin. Preoperative planning of microcatheter navigation and shaping were performed using the 3D vessel models. Before the procedure, microcatheter mandrels were bent manually to the intended angle, referring to the vessel model, and then sterilized. The 3D vessel models were also sterilized with plasma and used during the procedure. ResultsTwenty-six patients (27 aneurysms) were treated using a total of 48 microcatheters shaped while referring to the 3D printed vessel model. Of the 48 catheters, only 9 (19%) required modification of the initial shape due to inappropriate positioning of the catheter. Only 29% of the catheter placements required repositioning due to catheter kick back. There were no procedure-related complications, including aneurysm rupture. The responses from assistants to a questionnaire administered after the embolizations on the usefulness of the technique were favorable. ConclusionsTailor-made shaping of microcatheters may facilitate easier and safer procedures in coil embolization of intracranial aneurysm.

A new non-craniotomy model of subarachnoid hemorrhage in the pig: a pilot study.

Subarachnoid hemorrhage (SAH) from rupture of an intracranial arterial aneurysm is a devastating disease affecting young people, with serious lifelong disability or death as a frequent outcome. Large animal models that exhibit all the cardinal clinical features of human SAH are highly warranted. In this pilot study we aimed to develop a non-craniotomy model of SAH in pigs suitable for acute intervention studies. Six Norwegian Landrace pigs received advanced invasive hemodynamic and intracranial pressure (ICP) monitoring. The subarachnoid space, confirmed by a clear cerebrospinal fluid (CSF) tap, was reached by advancing a needle below the ocular bulb through the superior orbital fissure and into the interpeduncular cistern. SAH was induced by injecting 15 mL of autologous arterial blood into the subarachnoid space. Macro- and microanatomical investigations of the pig brain showed a typical blood distribution consistent with human aneurysmal SAH (aSAH) autopsy data. Immediately after SAH induction ICP sharply increased with a concomitant reduction in cerebral perfusion pressure (CPP). ICP returned to near normal values after 30 min, but increased subsequently during the experimental period. Signs of brain edema were confirmed by light microscopy post-mortem. None of the animals died during the experimental period. This new transorbital injection model of SAH in the pig mimics human aSAH and may be suitable for acute intervention studies. However, the model is technically challenging and needs further validation.

Neurovascular 4DFlow MRI (Phase Contrast MRA): emerging clinical applications

Recent advances in 4DFlow MRI (Phase Contrast MRA) acquisition and reconstruction enable high resolution exams to be obtained in practical imaging times. 4DFlow MRI provides images of vascular morphology and quantitative measurements of blood velocity throughout a 3D imaging volume. Hemodynamic parameters such as flow volume, relative wall shear stress, streamlines, vorticity and pressure gradients can be derived from the velocity data. The combination of anatomic vessel wall imaging, lumen visualization and physiologic data derived from accelerated 4DFlow MRI augments the characterization of intracranial arterial stenosis, aneurysms, vascular malformations and dural sinus pathology. This review provides an update for clinicians interested in 4DFlow MRI of the brain.

Treatment methods of residue or recurrence after intracranial aneurysm embolization

Objective To explore how to effectively manage the residual or recurrent intracranial aneurysms after embolization. Methods The treatment methods and clinical efficacy of 36 patients with residual or recurrent intracranial aneurysm after procedure at the Department of Neurosurgery, Tianjin Huanhu Hospital from June 2010 to June 2014 were analyze retrospectively. Among 36 patients, 12 underwent endovascular embolization, 15 underwent surgical clipping directly, and 9 could not be clipped directly were treated by extracranial and intracranial arterial bypass and aneurysm trapping or combined embolization. Results The Glasgow outcome scale (GOS) scores of 36 patients after procedure and at discharge showed that 32 (89%) recovered well, 3 (8%) had severe disability, and 1died (3%). They were followed up for an average of 2 years. Thirty-three patients (92%) recovered well, 2 (6%) had disability. During the follow-up period 3 had recurrent aneurysm, 2 of them were retreated by endovascular intervention, and 1 was treated with craniotomy clipping. Cerebrovascular examination revealed that all the grafts were patent. Conclusions For residual or recurrent intracranial aneurysms after embolization, the determination of treatment method should be based on the clinical status of patients, aneurysmal characteristics, surgical risk, and possibility of rerupture of aneurysms. The safe and effective personalized treatment can be performed in clinical practice by the methods of craniotomy or endovascular interventional therapy, and it will achieve a satisfactory clinical effect. Key words: Intracranial aneurysm; Recurrence; Embolization, therapeutic; Microsurgery

Intracranial dural arteriovenous fistula as a cause for symptomatic superficial siderosis: A report of two cases and review of the literature.

Background:Superficial siderosis (SS) is the occult deposition of hemosiderin within the cerebral cortex due to repeat microhemorrhages within the central nervous system. The collection of hemosiderin within the pia and superficial cortical surface can lead to injury to the nervous tissue. The most common presentation is occult sensorineural hearing loss although many patients have been misdiagnosed with diseases such as multiple sclerosis and amyotrophic lateral sclerosis before being diagnosed with SS. Only one case report exists in the literature describing an intracranial dural arteriovenous fistula (dAVF) as the putative cause for SS.Case Description:We describe two cases of SS caused by a dAVF. Both patients had a supratentorial, cortical lesion supplied by the middle meningeal artery with venous drainage into the superior sagittal sinus. In both patients, symptoms improved after endovascular embolization. The similar anatomic relationship of both dAVFs reported presents an interesting question about the pathogenesis of SS. Similar to the pathologic changes seen in the formation of intracranial arterial aneurysms; it would be possible that changes in the blood vessel lining and wall might predispose a patient to chronic, microhemorrhage resulting in SS.Conclusions:We describe the second and third cases of a dAVF as the cause of SS, and the first cases of successful treatment of SS-associated dAVF with endovascular embolization. As noninvasive imaging techniques become more sensitive and easily obtained, one must consider their limitations in detecting occult intracranial vascular malformations such as dAVF as a possible etiology for SS.

Superficial Temporal Artery-Middle Cerebral Artery Bypass (STA-MCA) for Middle Cerebral Artery Dissecting Aneurysm in a Child

Intracranial arterial dissection or dissecting aneurysm is relatively uncommon and usually involve the vertebrobasilar system. Here we report a pediatric case of middle cerebral artery dissection/dissecting aneurysm with sub arachnoid hemorrhage and Sylvian fissure hematoma on dominant side. After initial evacuation of hematoma, we went for trapping and excision of dissection/dissecting aneurysm followed by STA-MCA bypass. Patient recovered fully from her neurological deficit. Probably this is the first reported case of STA-MCA bypass in Bangladesh.J Bangladesh Coll Phys Surg 2014; 32: 94-98