Prasugrel Single Antiplatelet Therapy versus Aspirin and Clopidogrel Dual Antiplatelet Therapy for Flow Diverter Treatment for Cerebral Aneurysms: A Retrospective Multicenter Study

BACKGROUND AND PURPOSE

The optimal antiplatelet regimen after flow diverter treatment of cerebral aneurysms is still a matter of debate. A single antiplatelet therapy might be advantageous in determined clinical scenarios. This study evaluated the efficacy and safety of prasugrel single antiplatelet therapy versus aspirin and clopidogrel dual antiplatelet therapy.

MATERIALS AND METHODS

We performed a post hoc analysis of 4 retrospective multicenter studies including ruptured and unruptured aneurysms treated with flow diversion using either prasugrel single antiplatelet therapy or dual antiplatelet therapy. Primary end points were the occurrence of any kind of procedure- or device-related thromboembolic complications and complete aneurysm occlusion at the latest radiologic follow-up (mean, 18 months). Dichotomized comparisons of outcomes were performed between single antiplatelet therapy and dual antiplatelet therapy. Additionally, the influence of various patient- and aneurysm-related variables on the occurrence of thromboembolic complications was investigated using multivariable backward logistic regression.

RESULTS

A total of 222 patients with 251 aneurysms were included, 90 (40.5%) in the single antiplatelet therapy and 132 (59.5%) in the dual antiplatelet therapy group. The primary outcome-procedure- or device-related thromboembolic complications-occurred in 6 patients (6.6%) of the single antiplatelet therapy and in 12 patients (9.0%) of the dual antiplatelet therapy group (P = .62; OR, 0.712; 95% CI, 0.260-1.930). The primary treatment efficacy end point was reached in 82 patients (80.4%) of the single antiplatelet therapy and in 115 patients (78.2%) of the dual antiplatelet therapy group (P = .752; OR, 1.141; 95% CI, 0.599-2.101). Logistic regression showed that non-surface-modified flow diverters (P = .014) and fusiform aneurysm morphology (P = .004) significantly increased the probability of thromboembolic complications.

CONCLUSIONS

Prasugrel single antiplatelet therapy after flow diverter treatment may be as safe and effective as dual antiplatelet therapy and could, therefore, be a valid alternative in selected patients. Further prospective comparative studies are required to validate our findings.

Dynamic (live) 3D roadmap as navigational tool in multiplug brain arteriovenous malformation embolization: technical note

PURPOSE

Treatment of brain arteriovenous malformation (bAVM) includes microsurgical excision, stereotactic radiosurgery, endovascular embolization, or combination. With bAVM embolization, complete angiographic obliteration ranges from 12.5 to 51%, and higher total occlusion rate is seen in SM grades I to III, ranging from 96 to 100%.

METHODS

In this paper, we illustrate the use of 3D rotational angiography and dynamic (live) 3D roadmap functions in endovascular treatment of bAVM. A single dynamic 3D roadmap or two dynamic 3D roadmaps obtained help tremendously in navigation of microcatheters and wires along the parent artery and bAVM feeders.

RESULTS

This method eliminates the need for repeated 2D angiograms and roadmaps for new working projections every time the C-arm position is changed for cannulation of different feeders, thereby reducing radiation dose. No instances of misalignment error, vascular perforation, or thromboembolic phenomena were observed in the 21 embolization cases performed within the previous 2 years while utilizing this feature.

CONCLUSION

The dynamic 3D roadmap is an extremely useful tool for multiple-feeder cannulation, by reducing the use of multiple 2D angiograms, providing intraprocedural live and adjustable 3D roadmap for better mental orientation to angioarchitecture of the bAVM, which further aids in the overall complete angiographic obliteration rate of bAVM in a single session especially in multiplug embolization technique.

Magnetic resonance perfusion imaging findings following flow diversion in patients with complex middle cerebral artery bifurcation aneurysms: a single-center analysis regarding the jailed cortical branches

BACKGROUND

Flow diverter (FD) devices provide a safe and effective treatment option especially for wide-necked intracranial aneurysms. One of the main concerns in patients treated with FD devices is patency of arterial branches jailed by the stent. However, there are no long-term data from magnetic resonance perfusion (MRP) studies regarding jailed branches. In this study we aimed to reveal the MRP findings in patients with jailed middle cerebral artery (MCA) cortical branches during long-term follow-up after flow diversion.

METHODS

Patients who underwent FD stent treatment for MCA aneurysms with a resulting jailed cortical branch were included. Follow-up clinical, angiographic, and MRP examination findings were recorded. Different MRP parameters were measured in the MCA territory regarding the jailed branches.

RESULTS

Eighteen patients treated endovascularly with flow diversion for a total of 20 MCA aneurysms were included. At angiographic follow-up (median 35 months, range 7-95 months) complete occlusion was observed in 13 (65%) aneurysms and partial occlusion was observed in 6 (30%). The mean transit time (MTT) prolongation, MTT ratio, time-to peak (TTP) prolongation, and TTP ratio were 1.34, 1.20, 1.18, and 1.06 s, respectively, when compared with the contralateral side in the MCA territory. MTT, TTP, and cerebral blood volume values of the patients showed statistically significant differences compared with the contralateral side (P<0.05).

CONCLUSIONS

Flow diversion treatment of complex bifurcation aneurysms can be effective and safe. MRP examination may reveal perfusion changes in the territory vascularized via a jailed branch, and these changes are rarely accompanied by clinical findings.

Imaging findings of intraventricular pilocytic astrocytoma

OBJECTIVE

The aim of this study is to present the clinical and imaging findings of 16 patients with intraventricular pilocytic astrocytomas (PAs).

METHODS

16 patients with histopathological diagnosis of intraventricular PA between February 2016 and January 2022 were evaluated retrospectively. Imaging and clinical findings of the patients, as well as apparent diffusion coefficient (ADC) measurements were analyzed.

RESULTS

Of 16 patients, 8 (%50) were male and 8 (%50) were female. The mean age of the patients was 20.8 years (2-44 years range). The most common symptoms in the patients were headache and ataxia. The mean long-axis size of lesions was found to be 48.19 ± 21.59 (range, 15-92 mm). 9 out of 16 lesions (56.2%) were located in the fourth ventricle. The majority of the lesions were iso-hypointense in T1W and hyperintense in T2W images. The mean ADC value of PAs was 1.57 × 10-3 ± 0.2 mm2/s, while the mean thalamic ADC and white matter ADC values were found to be 0.78 × 10-3 ± 0.04 and 0.76 × 10-3 ± 0.06 mm2/s, respectively. There was a statistically significant difference between the ADC values obtained from the solid components of the lesions and the thalami/white matter (p < 0.001).

CONCLUSION

PAs often originate from midline structures, however, they can also be located intraventricularly. Although intraventricular PAs are frequently seen in pediatric population, it should be kept in mind that they can also be seen in adults, albeit rarely.

ADVANCES IN KNOWLEDGE

PA should be considered in the differential diagnosis of intraventricular neoplasms in case of high ADC values.

Safety and Efficacy of Flow Diverters for Treatment of Unruptured Anterior Communicating Artery Aneurysms: Retrospective Multicenter Study

BACKGROUND

The anterior communicating artery (AComm) region is the most common site of intracranial aneurysms, with increased rupture risk compared with other locations. Overall, flow diverters present as a safe and efficacious treatment for intracranial aneurysms, but there is paucity of data for their use in the treatment of unruptured AComm aneurysms. We present the largest multicentric analysis evaluating the outcomes of flow diverters in AComm aneurysm treatment.

METHODS

Databases from 10 centers were retrospectively reviewed for unruptured AComm aneurysms treated with flow diverters. Demographics, clinical presentation, radiographic characteristics, procedural complications, and outcomes were assessed.

RESULTS

A total of 144 patients harboring 147 AComm aneurysms were treated between January 2012 and December 2021. Seventy-four were women (51.4%) and median age was 60 (IQR 50-67) years. All were unruptured AComm aneurysms. Half of the cohort had similar anterior cerebral artery sizes (51.4%). The most common morphology was saccular (94.6%), with a branch involvement in 32.7% of cases. Median vessel diameter was 2.4 mm, and the Pipeline Flex was the most prevalent device (32.7%). Median follow-up time was 17 months, with complete occlusion in 86.4% at the last follow-up. Functional independence (modified Rankin Scale score 0-2) was reported in 95.1%. Intraprocedural complications occurred in 5.6%, and postoperative complications were noted in 9.7% of cases. Combined major complication and mortality rate was 2.1%.

CONCLUSIONS

Our study suggests that flow diverters are a useful treatment for AComm aneurysms. Mid-term results indicated favorable aneurysm occlusion with a good safety profile. Additional prospective studies with longer follow-up periods and independent adjudication are warranted to better assess these results.

Evaluation of short- and long-term results of Y-stent-assisted coiling with Leo stents in endovascular treatment of wide-necked intracranial bifurcation aneurysms

PURPOSE

This study aimed to evaluate the feasibility, safety, and efficacy of Y-stent-assisted coiling (Y-SAC) using LEO Baby® stents in treating of bifurcation aneurysms.

METHODS

Patients who underwent Y-SAC using a braided stent (LEO Baby®, Montmorency, France) for wide-necked intracranial aneurysms between 2009 and 2019 and whose radiological and clinical follow-up data for at least 6 months could be obtained were evaluated. Data were obtained from patient records and analyzed retrospectively.

RESULTS

We evaluated 111 patients with a mean age of 56.0 ± 10.8 years (range, 25-88 years). Most of the aneurysms were detected incidentally. Three patients had ruptured aneurysms. LEO Baby deployment and coiling were successful in all patients. Immediate aneurysm occlusion rates were determined as modified Raymond-Roy classification (mRRC) I 95.5% (n = 106), mRRC II 3.6% (n = 4), mRRC IIIa 0.9% (n = 1). In the sixth month, aneurysm occlusion rates were found to be complete and nearly complete in all patients (mRRC I 94.6%, n = 105 and mRRC II 4.5%; n = 5, respectively). Follow-up data of 91 patients for > 2 years were obtained. Of these, 88 had MRRCI obstruction and 3 had MRRC II obstruction. The overall complication rate was 4.8%, and one patient died during the post-procedural follow-up.

CONCLUSION

The long-term follow-up results of Y-stenting with LEO Baby revealed that it provides stable closure of the aneurysm sac while preserving the main arterial structures. Therefore, it is a safe, durable, and effective method for treating wide-necked and complex bifurcation aneurysms.

Efficacy of Dural Sinus Quantitative Measurements in Idiopathic Intracranial Hypertension : A Practical Diagnostic Feature

BACKGROUND AND PURPOSE

This study aimed to investigate the potential contribution of quantitative measurements of dural venous sinuses to the diagnosis of idiopathic intracranial hypertension (IIH) and the relationship between IIH and dural venous sinus dimensions on 3D post-gadolinium T1-weighted magnetic resonance (MR) images.

MATERIAL AND METHODS

A total of 129 individuals (57 IIH patients and 72 controls) who complained of headache and underwent both magnetic resonance venography (MRV) and precontrast/postcontrast 3D T1-weighted MR imaging between 2018 and 2021 were included in this retrospective study. Dural venous sinus and jugular vein diameters were measured in all cases using post-gadolinium 3D T1 TFE images. The presence of transverse sinus (TS) hypoplasia and occipital sinus variation, the number and size of arachnoid granulations in the TS, and the presence of brain parenchymal herniation were also evaluated. Cut-off values that maximized accurate diagnosis of IIH were established on the receiver operating characteristic curve. The sensitivity and specificity of the diagnosis of IIH based on quantitative measurements of the dural sinus were calculated.

RESULTS

The ratios of the maximum to minimum TS diameters and the minimum TS diameters to minimum sigmoid sinus (SS) diameters were significantly higher in IIH patients than in the control group (p < 0.001). The diagnostic sensitivity and specificity values of TS_max/TS_min and TS_{min sum}/SS_{min sum} parameters for the detection of IIH were 84.2%, 84.7% and 83.3%, 84.2%, respectively.

CONCLUSION

Practical measurements from multiplanar T1 sequences can be useful for both quantitative assessment and overcoming misinterpretation due to anatomical variation.

Spontaneous internal carotid artery dissection in a child diagnosed by high resolution vessel wall MRI

Craniocervical dissection is one of the most common causes of stroke in children. Although the most common cause of dissection is trauma, spontaneous dissections in which no cause can be revealed may also occur. The diagnosis of this type of dissection in children can be challenging with the preferred non-invasive imaging methods (MRA, CTA). Intracranial vessel wall imaging is a promising novel method for identifying specific signs of dissection. We report an 11-year-old girl with spontaneous ICA dissection, whose diagnosis was confirmed by an MRI of the intracranial vessel wall. Vessel wall imaging has contributed substantially to the diagnosis and follow-up of this case.

Learning Curve for Flow Diversion of Posterior Circulation Aneurysms: A Long-Term International Multicenter Cohort Study

BACKGROUND AND PURPOSE

Flow diversion has gradually become a standard treatment for intracranial aneurysms of the anterior circulation. Recently, the off-label use of the flow diverters to treat posterior circulation aneurysms has also increased despite initial concerns of rupture and the suboptimal results. This study aimed to explore the change in complication rates and treatment outcomes across time for posterior circulation aneurysms treated using flow diversion and to further evaluate the mechanisms and variables that could potentially explain the change and outcomes.

MATERIALS AND METHODS

A retrospective review using a standardized data set at multiple international academic institutions was performed to identify patients with ruptured and unruptured posterior circulation aneurysms treated with flow diversion during a decade spanning January 2011 to January 2020. This period was then categorized into 4 intervals.

RESULTS

A total of 378 procedures were performed during the study period. Across time, there was an increasing tendency to treat more vertebral artery and fewer large vertebrobasilar aneurysms (P = .05). Moreover, interventionalists have been increasingly using fewer overlapping flow diverters per aneurysm (P = .07). There was a trend toward a decrease in the rate of thromboembolic complications from 15.8% in 2011-13 to 8.9% in 2018-19 (P = .34).

CONCLUSIONS

This multicenter experience revealed a trend toward treating fewer basilar aneurysms, smaller aneurysms, and increased usage of a single flow diverter, leading to a decrease in the rate of thromboembolic and hemorrhagic complications.

Safety and Efficacy of the FRED Jr Flow Re-Direction Endoluminal Device for Intracranial Aneurysms: Retrospective Multicenter Experience With Emphasis on Midterm Results

Background and Purpose: Flow diversion is increasingly used as an endovascular treatment for intracranial aneurysms. In this retrospective multicenter study, we analyzed the safety and efficacy of the treatment of intracranial, unruptured, or previously treated but recanalized aneurysms using Flow Re-Direction Endoluminal Device (FRED) Jr with emphasis on midterm results.

Materials and Methods: Clinical and radiological records of 150 patients harboring 159 aneurysms treated with FRED Jr at six centers between October 2014 and February 2020 were reviewed and consecutively included. Clinical outcome was measured by using the modified Rankin Scale (mRS). Anatomical results were assessed according to the O'Kelly-Marotta (OKM) scale and the Cekirge-Saatci Classification (CSC) scale.

Results: The overall complication rate was 24/159 (16%). Thrombotic-ischemic events occurred in 18/159 treatments (11%). These resulted in long-term neurological sequelae in two patients (1%) with worsening from pre-treatment mRS 0–2 and mRS 4 after treatment. Complete or near-complete occlusion of the treated aneurysm according to the OKM scale was reached in 54% (85/158) at 6-month, in 68% (90/133) at 1-year, and in 83% (77/93) at 2-year follow-up, respectively. The rates of narrowing or occlusion of a vessel branch originating from the treated aneurysm according to the CSC scale were 11% (12/108) at 6-month, 20% (17/87) at 1-year, and 23% (13/57) at 2-year follow-up, respectively, with all cases being asymptomatic.

Conclusions: In this retrospective multicenter study, FRED Jr was safe and effective in the midterm occlusion of cerebral aneurysms. Most importantly, it was associated with a high rate of good clinical outcome.

Endovascular management of anterior falcotentorial dural arteriovenous fistulas: importance of functionality of deep venous system and existence of accompanying choroidal arteriovenous malformation

BACKGROUND

Anterior falcotentorial junction dural arteriovenous fistulas (AFDAVFs) are the most deeply located and most complex type of tentorial fistula due to their location and vascular anatomy. We aimed to make new angiographic definitions of AFDAVF nidus and functionality of the deep venous system of the brain and thereby provide a safer approach for endovascular treatment.

METHODS

We retrospectively examined 18 patients with AFDAVF who received endovascular treatment at our neuroradiology department between June 2002 and May 2019. Pre- and post-treatment clinical assessments were performed using the modified Rankin Scale. AFDAVF niduses were defined as mixed-type or pure-dural-type on the basis of whether choroidal arteriovenous malformation was coexisting or not, respectively. The deep venous system was denoted as functional or nonfunctional.

RESULTS

We included 13 men and 5 women (mean (range) age, 47.2 (31-62) years). We evaluated 15 patients with pure-dural-type AFDAVFs and three with mixed-type AFDAVFs. Complete occlusion of the fistula was achieved in 15/18 patients. Three patients had transient neurologic symptoms. In two patients these were due to mild thalamic ischemia and in the third patient was due to tectal venous ischemia, all in mixed-type AFDAVF. One patient also developed Parinaud syndrome due to compression of the tectal plate by a thrombosed large vein of Galen. No patients died or developed permanent morbidity.

CONCLUSION

Evaluating AFDAVFs as described here using our new subtyping model will help improve analysis of the malformation and development of a safer endovascular strategy, and hence may prevent periprocedural complications and improve treatment safety.

Flow Redirection Endoluminal Device (FRED) with or without Adjunctive Coiling in Treatment of Very Large and Giant Cerebral Aneurysms

PURPOSE

Flow diverter stents are gaining wider use in the treatment of complex intracranial aneurysms; however, there are limited data on occlusion and complication rates of flow diverters in very large and giant aneurysms. This study assessed the safety and efficacy of flow redirection endoluminal device (FRED) and FRED Jr. stents in aneurysms ≥ 20 mm.

METHODS

We retrospectively analyzed all aneurysms ≥ 20 mm treated with FRED/FRED Jr. between January 2010 and June 2020 from three centers. Endpoints for clinical safety were absence of major stroke, aneurysmal rupture, or death and complete or near-complete occlusion for efficacy.

RESULTS

A total of 45 patients with very large (28 cases) and giant aneurysms (17 cases) were treated with FRED (41 cases), and FRED Jr. (4 cases) stents. The majority of the aneurysms (40/45, 88.9%) were in the anterior circulation. Adjunctive aneurysm coiling was performed in 21 aneurysms (46.7%). Technical complications were encountered in 4 procedures (8.9%). Ischemic and hemorrhagic complication rates were 6.7% and 8.9%, respectively. There was no case with major stroke. The mortality rate was 8.9%, and all cases were due to hemorrhagic complications from aneurysmal rupture. Median angiographic follow-up was 21.5 months (range 3-60 months). Complete occlusion was achieved in 32 aneurysms (71.1%), and near-complete occlusion in 5 cases (11.1%).

CONCLUSION

The use of FRED/FRED Jr. for the treatment of aneurysms ≥ 20 mm achieved a long-term aneurysm occlusion rate and a safety profile comparable to the large series reported with other flow diverter stents.

Long-term safety and efficacy of distal aneurysm treatment with flow diversion in the M2 segment of the middle cerebral artery and beyond

BACKGROUND

Indications for flow diversion stent (FDS) treatment are expanding. However, there is still a lack of evidence for the long-term outcome in distally located aneurysms in the M2 segment of the middle cerebral artery (MCA) and beyond.

METHODS

Consecutive subjects (from June 2013 to August 2020) with MCA aneurysms in the M2 segment or beyond treated with FDS were reviewed retrospectively. The primary endpoints for clinical safety were the absence of mortality, stroke event, re-rupture of the aneurysm, and worsening of clinical symptoms. The primary endpoint for treatment efficacy was complete/near-complete occlusion at follow-up after 12 months.

RESULTS

23 patients were identified: 7 aneurysms were located in the M2 segment of the MCA, 4 in the M2-M3 bifurcation, 2 in M3, 3 in M3-4 branching, and 2 in M4; 5 aneurysms were located in M2 with extension into the M1-M2 bifurcation. 13 aneurysms were of fusiform morphology, 8 sacculofusiform, and 2 saccular. 16 aneurysms were of highly suspected dissecting etiology. The median diameter of the parent vessel was 2.1 mm proximally and 2 mm distally. The median time of the follow-up was 30 months (range 16 months to 6 years). Complete/near complete occlusion was observed in 14/20 patients (70%) and one stable remodeling (5%) was seen at 12 months. 22 patients (95.6%) had an excellent clinical outcome (mRS 0-1) at 6 months. Technical challenges associated with the deployment of FDS occurred in 8.7% of cases. Severe complications, intraparenchymal hemorrhage and re-rupture of the aneurysm occurred in 2 patients (8.7%).

CONCLUSION

Flow diversion of distally located aneurysms is technically feasible with low morbidity and mortality.

Does measurement of the jugular foramen diameter on MRI help to differentiate transverse sinus thrombosis from unilateral transverse sinus hypoplasia?

BACKGROUND AND PURPOSE

The transverse sinus (TS) is a frequent location of cerebral venous thrombosis. However, unilateral TS hypoplasia is a frequent variation and radiological imaging pitfall in the diagnosis because it may mimic unilateral TS thrombosis. The purpose of this study is to find a cutoff value for bilateral jugular foramen (JF) diameter ratios on magnetic resonance imaging (MRI) for differentiating TS thrombosis from TS hypoplasia.

MATERIALS AND METHODS

We retrospectively reviewed magnetic resonance venography results for 174 patients with reduced unilateral TS caliber resulting from either unilateral thrombosis (80 patients) or unilateral hypoplasia (94 patients). We calculated the ratio by proportioning the diameter of the JF ipsilateral to the TS with caliber reduction to the diameter of the contralateral JF. The Mann-Whitney U test was used to compare the ratios between thrombosis and hypoplasia groups, and the cutoff value was calculated by receiver-operating characteristic curve analysis.

RESULTS

The ratio of bilateral JF diameters was lower in patients with hypoplasia than those with thrombosis (P < .01). The cutoff value to determine the diagnosis of TS hypoplasia with maximum accuracy was 0.638, with a sensitivity of 91.3% and specificity of 64.9%.

CONCLUSION

In equivocal cases, calculating the cutoff value by proportioning the diameter of JF ipsilateral to the TS with caliber reduction to the contralateral JF seems to be an efficient, quick, and straightforward method and valuable aid to differentiate TS thrombosis from TS hypoplasia.

Endovascular treatment of anterior cranial fossa dural arteriovenous fistula: a multicenter series

PURPOSE

We report a multicenter experience using endovascular embolization as the first line approach for treatment of anterior cranial fossa (ACF) dural arteriovenous fistula (DAVF).

METHODS

All patients with DAVFs located in the anterior cranial fossa who were treated with endovascular technique as a first line approach were included. Demographics, clinical presentation, angioarchitecture, strategy, complications, immediate angiographic, and follow-up results were included in the analysis.

RESULTS

Twenty-three patients met the inclusion criteria (18 male and 5 female). Age ranged from 14 to 79 years (mean 53 years). Twelve patients presented with hemorrhage. Twenty-eight endovascular procedures were performed. The overall immediate angiographic cure rate after endovascular treatment was 82.6% (19/23 patients). The angiographic cure rate of the transvenous strategy was significantly superior to the transarterial strategy (p ≤ 0.001). There was 1 complication in 28 total procedures (3.6%). Angiographic follow-up was available in 21 out of the 23 patients with a mean of 25 months (range 2 to 108 months). In these 21 patients, the DAVF was completely cured in 20 (95%). At last follow-up, all patients had a modified Rankin scale (mRS) 0 to 2.

CONCLUSION

Our experience suggests that endovascular treatment for ACF DAVFs has an acceptable safety profile with high rates of complete occlusion, particularly with transvenous approach. Whenever possible, transvenous approach should be preferred over transarterial approach as first line strategy.

Comparison of PED and FRED flow diverters for posterior circulation aneurysms: a propensity score matched cohort study

BACKGROUND

Flow diversion is a common endovascular treatment for cerebral aneurysms, but studies comparing different types of flow diverters are scarce.

OBJECTIVE

To perform a propensity score matched cohort study comparing the Pipeline Embolization Device (PED) and Flow Redirection Intraluminal Device (FRED) for posterior circulation aneurysms.

METHODS

Consecutive aneurysms of the posterior circulation treated at 25 neurovascular centers with either PED or FRED were collected. Propensity score matching was used to control for age, duration of follow-up imaging, adjunctive coiling, and aneurysm location, size, and morphology; previously ruptured aneurysms were excluded. The two devices were compared for the following outcomes: procedural complications, aneurysm occlusion, and functional outcome.

RESULTS

A total of 375 aneurysms of the posterior circulation were treated in 369 patients. The PED was used in 285 (77.2%) and FRED in 84 (22.8%) procedures. Aneurysms treated with the PED were more commonly fusiform and larger than those treated with FRED. To account for these important differences, propensity score matching was performed resulting in 33 PED and FRED unruptured aneurysm pairs. No differences were found in occlusion status and neurologic thromboembolic or hemorrhagic complications between the two devices. The proportion of patients with favorable functional outcome was higher with FRED (100% vs 87.9%, p=0.04).

CONCLUSION

Comparative analysis of PED and FRED for the treatment of unruptured posterior circulation aneurysms did not identify significant differences in aneurysm occlusion or neurologic complications. Variations in functional outcomes warrant additional investigations.

Intrathecal use of gadobutrol for gadolinium-enhanced MR cisternography in the evaluation of patients with otorhinorrhea

PURPOSE

Intrathecal gadolinium-enhanced MR cisternography (IGE-MRC) has a high sensitivity to detect accurate localization of cerebrospinal fluid (CSF) leakage in otorhinorrhea patients. Our purpose in this study was to describe our experience in analyzing clinically suspected CSF leakage by IGE-MRC by using gadobutrol with emphasis on its safety and diagnostic performance.

METHODS

We retrospectively reviewed our imaging and clinical database for the evaluation of patients admitted to our clinic with complaints of otorhinorrhea between 2017 and 2019. Two radiologists evaluated the imaging studies independently. Consensus data was used in the analysis. Medical record review and phone call were used for the follow-up.

RESULTS

Of the 85 patients included in the retrospective analysis, 82 (96.5%) had rhinorrhea and 3 (3.5%) had otorrhea. Overall, 29 patients (34.1% of all patients) underwent operation for repair of the CSF leakage site. Beta-transferrin test was available and positive in 33 patients (38.8%). Five (5.9%) patients complained headaches after the procedure and complaints were resolved with increased water intake. Postprocedurally, 3 patients (3.5%) had vertigo and 1 patient (1.2%) complained nausea but spontaneous regression were observed in a few hours. None of the patients experienced a significant complication or adverse reaction during follow-up period. Sixty-seven patients (78.8%) had medical record and telephone follow-up. Mean follow-up duration with call was 14.2 months.

CONCLUSION

IGE-MRC is a minimally invasive and highly sensitive imaging technique. The current results during our follow-up demonstrate the relative safety and feasibility of IGE-MRC by using gadobutrol to evaluate CSF leakage.

The FRED for Cerebral Aneurysms of the Posterior Circulation: A Subgroup Analysis of the EuFRED Registry

BACKGROUND AND PURPOSE

Flow diversion for the posterior circulation remains a promising treatment option for selected posterior circulation aneurysms. The Flow-Redirection Intraluminal Device (FRED) system has not been previously assessed in a large cohort of patients with posterior circulation aneurysms. The purpose of the present study was to assess safety and efficacy of FRED in this location.

MATERIALS AND METHODS

Consecutive patients with posterior circulation aneurysms treated at 8 centers participating in the European FRED study (EuFRED) between April 2012 and January 2019 were retrospectively reviewed. Complication and radiographic and functional outcomes were evaluated.

RESULTS

Eighty-four patients (median age, 54 years) with 84 posterior circulation aneurysms were treated with the FRED. A total of 25 aneurysms (29.8%) had previously ruptured, even though most aneurysms were diagnosed incidentally (45.2%). The intradural vertebral artery was the most common location (50%), and saccular, the most common morphology (40.5%). The median size was 7 mm. There were 8 (9.5%) symptomatic thromboembolic and no hemorrhagic complications. Thromboembolic complications occurred mostly (90.9%) in nonsaccular aneurysms. On last follow-up at a median of 24 months, 78.2% of aneurysms were completely occluded. Functional outcome at a median of 27 months was favorable in 94% of patients. All mortalities occurred in patients with acute subarachnoid hemorrhage and its sequelae.

CONCLUSIONS

The largest cohort of posterior circulation aneurysms treated with the FRED to date demonstrated favorable safety and efficacy profiles of the device for this indication. Treatment in the setting of acute subarachnoid hemorrhage was strongly related to mortality, regardless of whether procedural complications occurred.

The diagnostic value of quantitative texture analysis of conventional MRI sequences using artificial neural networks in grading gliomas

AIM

To explore the value of quantitative texture analysis of conventional magnetic resonance imaging (MRI) sequences using artificial neural networks (ANN) for the differentiation of high-grade gliomas (HGG) and low-grade gliomas (LGG).

MATERIALS AND METHODS

A total of 181 patients, 97 with HGG (53.5%) and 84 with LGG (46.5%) with brain MRI having T2-weighted (W) fluid attenuation inversion recovery (FLAIR), and contrast-enhanced T1W images were enrolled in the present study. Histogram parameters and high-order texture features were extracted using manually placed regions of interest (ROIs) on T2W-FLAIR and contrast-enhanced T1W images covering the whole volume of the tumours. The reproducibility of the features was assessed by interobserver reliability analyses. The cohort was divided into training (n=121) and test partitions (n=60). The training set was used for attribute selection and model development, and the test set was used to evaluate the diagnostic performance of the pre-trained ANNs in discriminating HGG and LGG.

RESULTS

In the test cohort, the ANN models using texture data of T2W-FLAIR and contrast-enhanced T1W images achieved an area under the receiver operating characteristic curve (AUC) of 0.87 and 0.86, respectively. The combined ANN model with selected texture features achieved the highest diagnostic accuracy equating 88.3% with an AUC of 0.92.

CONCLUSIONS

Quantitative texture analysis of T2W-FLAIR and contrast-enhanced T1W enhanced by ANN can accurately discriminate HGG from LGG and might be of clinical value in tailoring the management strategies in patients with gliomas.

A technical note on intra-arterial cone-beam computed tomography for the evaluation of flow-diverter stents: Image quality differences between diluted and non-diluted contrast medium

Background

Design of flow-diverter stents for flexibility, tractability, and low profile limits their radiopacity on conventional digital subtraction angiography. Cone-beam computed tomography (CBCT) offers higher spatial resolution for the evaluation of flow-diverter stents. However, CBCT requires optimal dilution and timing of contrast medium for simultaneous visualization of the stent, arterial lumen, and vessel wall. There are only limited data on the effects of different contrast dilutions on CBCT image quality in neurointerventional applications.

Materials and methods

In our institution, intra-arterial CBCTs were acquired during stent deployment and at follow-ups with 10% diluted contrast. We had recently started acquiring intra-arterial CBCTs with non-diluted contrast. Retrospective analysis of our flow-diverter data identified eight cases with different aneurysm locations who had intra-arterial CBCT with 10% diluted contrast immediately after flow-diverter stent deployment and with non-diluted contrast technique during follow-ups. For each case, the image quality between diluted and non-diluted contrast techniques was compared qualitatively by assessing stent visualization and quantitatively by plotting gray-scale intensity values along the vessel lumen.

Results

In two sets of CBCT images per each case, there was no substantial difference between diluted and non-diluted CBTC techniques for the evaluation of stent architecture and lumen opacification. Gray-scale intensity values perpendicular to the lumen revealed similar intensity values along the neighboring parenchyma, vessel wall, and lumen for the two different contrast techniques.

Conclusion

Intra-arterial CBCT angiography can be performed without contrast dilution and still achieve adequate image quality in certain cerebral aneurysms treated with flow diverter. The non-diluted contrast technique avoids the time loss during preparation of diluted contrast and installation of diluted contrast to the injector in angiography suites with a single power injector.

Machine learning-based quantitative texture analysis of conventional MRI combined with ADC maps for assessment of IDH1 mutation in high-grade gliomas

PURPOSE

To assess the performance of texture analysis of conventional magnetic resonance imaging (MRI) and apparent diffusion coefficient (ADC) maps in predicting IDH1 status in high-grade gliomas (HGG).

MATERIALS AND METHODS

A total of 142 patients with HGG were included in the study. IDH1 mutation was present in 48 of 142 HGG (33.8%). Patients were randomly divided into the training cohort (n = 96) and the validation cohort (n = 46). Texture features were extracted via regions of interest on axial T2WI FLAIR, post-contrast T1WI, and ADC maps covering the whole volume of the tumors. The training cohort was used to train the random forest classifier, and the diagnostic performance of the pre-trained model was tested on the validation cohort.

RESULTS

The random forest model of conventional MRI sequences and ADC images achieved diagnostic accuracy of 82.2% and 80.4% in predicting IDH1 status in the validation cohorts, respectively. The combined model of T2WI FLAIR, post-contrast T1WI, and ADC images exhibited the highest diagnostic accuracy equating 86.94% in the validation cohort.

CONCLUSION

Texture analysis of conventional MRI sequences enhanced by ML analysis can accurately predict the IDH1 status of HGG. Adding textural analysis of ADC maps to conventional MRI results in incremental diagnostic performance.

Long-term results of flow diversion in the treatment of intracranial aneurysms: a retrospective data analysis of a single center

PURPOSE

Endovascular techniques are frequently used for the treatment of intracranial aneurysms and flow diverter stents are relatively new and important devices in this field. The aim of our study is to report long-term follow-up results of flow diversion treatment.

METHODS

We retrospectively examined angiographic images and clinical reports of 133 patients (female, 112 [84%]; mean age, 46.3 years [range, 12-70 years]) who were treated with flow diverters between 2008 and 2013 and were followed up radiologically at least 1 year. The aneurysms treated with flow diverters were assessed according to technical problems, stent patency, residual filling, re-growth, and occlusion status, and the patients were assessed according to morbidity and mortality.

RESULTS

Except for ten patients, one aneurysm was treated per patient. Median duration of the follow-up was 927 days. Total occlusion rates in angiographic follow-up were found 76.2% for the sixth-month, 86.7% for the first-year, 93.6% for the third-year, 94.2% for the fifth-year, and 90.2% for entire follow-up period. Nine stent morphology changes were observed in the angiographic controls. Overall mortality and morbidity rates were 3.7% and 4.3%, respectively.

CONCLUSION

Despite technical difficulties and delayed hemorrhages, flow diverter stents are effective tools for the treatment of challenging aneurysms in the long run. Nonetheless, long-term results of flow diversion treatment must be evaluated hemodynamically and clinically in multicenter studies.

Preoperative evaluation of tumour consistency in pituitary macroadenomas: a machine learning-based histogram analysis on conventional T2-weighted MRI

PURPOSE

To evaluate the potential value of machine learning (ML)-based histogram analysis (or first-order texture analysis) on T2-weighted magnetic resonance imaging (MRI) for predicting consistency of pituitary macroadenomas (PMA) and to compare it with that of signal intensity ratio (SIR) evaluation.

METHODS

Fifty-five patients with 13 hard and 42 soft PMAs were included in this retrospective study. Histogram features were extracted from coronal T2-weighted original, filtered and transformed MRI images by manual segmentation. To achieve balanced classes (38 hard vs 42 soft), multiple samples were obtained from different slices of the PMAs with hard consistency. Dimension reduction was done with reproducibility analysis, collinearity analysis and feature selection. ML classifier was artificial neural network (ANN). Reference standard for the classifications was based on surgical and histopathological findings. Predictive performance of histogram analysis was compared with that of SIR evaluation. The main metric for comparisons was the area under the receiver operating characteristic curve (AUC).

RESULTS

Only 137 of 162 features had excellent reproducibility. Collinearity analysis yielded 20 features. Feature selection algorithm provided six texture features. For histogram analysis, the ANN correctly classified 72.5% of the PMAs regarding consistency with an AUC value of 0.710. For SIR evaluation, accuracy and AUC values were 74.5% and 0.551, respectively. Considering AUC values, ML-based histogram analysis performed better than SIR evaluation (z = 2.312, p = 0.021).

CONCLUSION

ML-based T2-weighted MRI histogram analysis might be a useful technique in predicting the consistency of PMAs, with a better predictive performance than that of SIR evaluation.

Added Value of Dynamic Contrast-Enhanced Magnetic Resonance Imaging in Predicting Response to Somatostatin Analogs in Acromegaly Patients

AIM

To investigate the added value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) sequences in predicting somatostatin analog (SSA) responses in patients with acromegaly.

MATERIAL AND METHODS

This study included 55 active acromegaly patients with macroadenoma. Mean and maximum signal intensities were measured using region of interests in T2-weighted (T2W) and DCE-MRI sequences. Semi-quantitative values indicating relative signal intensity ratios and contrast-enhanced kinetics were obtained. Bivariate and multivariate analyses were used to determine whether the pathological granulation pattern of adenomas (dense versus others) was associated with patients' demographic variables and semi-quantitative MRI parameters.

RESULTS

Three parameters formed the logistic model, x2(3)=23.278, p < 0.0001: age (odds ratio [OR]=1.08), hypointensity of adenomas in T2W images (OR=15.45), and high maximum enhancement ratio in the second interval (ER2max) values (OR=2195.74). The overall accuracy of this model was 85.45% with an area under the curve of 0.880. Sensitivity, specificity, positive predictive, and negative predictive values of the model were 68.75%, 92.31%, 78.58%, and 87.8%, respectively.

CONCLUSION

In patients with newly diagnosed acromegaly, the model created based on the relative T2W signal intensity, patient's age, and ER2 < submax parameter from DCE-MRI sequences might be used to more accurately predict SSA responses.

Apparent diffusion coefficient characteristics of parenchymal neuro-Behçet's disease

AIM

To evaluate apparent diffusion coefficient (ADC) characteristic of parenchymal neuro-Behçet's disease (NBD).

METHODS

We retrospectively reviewed cranial magnetic resonance imaging (MRI) examinations of NBD patients with acute or chronic parenchymal lesions. ADC measurements of the lesions and contralateral normal brain parenchyma were performed by a consensus of two radiologists. To compare the ADC value of the chronic and acute lesions, relative ADC values (rADC) were calculated. The ratio of the lesions' ADC to contralateral normal brain parenchyma ADC yielded a rADC value of the lesions. Contrast enhancement patterns and the locations of the lesions were also noted.

RESULTS

A total of 24 NBD patients with 45 parenchymal lesions, 25 acute, and 20 chronic, were enrolled in the study. A significant difference was observed between the mean ADC value of the acute lesions (1074.48 ± 138.31 m/s) and the mean ADC value of the contralateral normal brain parenchyma (841.20 ± 142.96 m/s; P < 0.0001). A significant difference was observed between the mean ADC value of the chronic lesions (1069.95 ± 143.95 m/s) and the mean ADC value of the contralateral normal brain parenchyma (793.90 ± 96.71 m/s; P < 0.0001). No significant difference was observed between the mean rADC (1.35 ± 0.20) and the mean rADC value of the chronic lesions (1.29 ± 0.15; P = 0.22).

CONCLUSIONS

ADC measurements might provide substantial information about the histopathological aspect of parenchymal NBD lesions.

Assessment of the common carotid artery wall stiffness by Shear Wave Elastography in Behcet's disease

AIM

To evaluate endothelial dysfunction and subclinical atherosclerosis in Behcet's disease (BD) by measuring the common carotid artery (CCA) wall stiffness and carotid intima-media thickness (CIMT).

MATERIALS AND METHODS

We prospectively evaluated CIMT and the CCA wall stiffness of 34 BD patients and 28 age/sex-matched controls. CIMT measurements were performed from the posterior wall of the carotid artery approximately 10 mm proximal to the initiation of the carotid bulb using B-mode ultrasound. The stiffness of the CCA was measured from the superficial wall of the CCA using shear wave elastography (SWE). SWE measurements were recorded as shear wave velocity (SWV) using m/s as a unit.

RESULTS

The mean right (0.5±0.11 mm) and left (0.5±0.14 mm) CIMT of the patients were significantly higher compared to the mean right (0.41±0.07 mm) and left (0.41±0.11 mm) CIMT of the healthy controls (p=0.001 and p= 0.003 respectively). The mean right (3.72±0.94 m/s) and left (3.57±0.72 m/s) CCA wall stiffness of the patients were significantly higher compared to the mean right (2.42±0.49 m/s) and left (2.56±0.49 m/s) CCA wall stiffness of the controls (p<0.001 for both).

CONCLUSIONS

SWE seems to be a promising modality to evaluate endothelial dysfunction in BD by interpreting the arterial stiffness, and SWE might be an important adjunct to clinical and laboratory findings, and imaging modalities to assess cardiovascular risk in BD. Moreover, SWE evaluation of the arterial stiffness might assist us to understand pathophysiological aspects of BD.

Predicting response to somatostatin analogues in acromegaly: machine learning-based high-dimensional quantitative texture analysis on T2-weighted MRI

OBJECTIVE

To investigate the value of machine learning (ML)-based high-dimensional quantitative texture analysis (qTA) on T2-weighted magnetic resonance imaging (MRI) in predicting response to somatostatin analogues (SA) in acromegaly patients with growth hormone (GH)-secreting pituitary macroadenoma, and to compare the qTA with quantitative and qualitative T2-weighted relative signal intensity (rSI) and immunohistochemical evaluation.

METHODS

Forty-seven patients (24 responsive; 23 resistant patients to SA) were eligible for this retrospective study. Coronal T2-weighted images were used for qTA and rSI evaluation. The immunohistochemical evaluation was based on the granulation pattern of the adenomas. Dimension reduction was carried out by reproducibility analysis and wrapper-based algorithm. ML classifiers were k-nearest neighbours (k-NN) and C4.5 algorithm. The reference standard was the biochemical response status. Predictive performance of qTA was compared with those of the quantitative and qualitative rSI and immunohistochemical evaluation.

RESULTS

Five hundred thirty-five out of 828 texture features had excellent reproducibility. For the qTA, k-NN correctly classified 85.1% of the macroadenomas regarding response to SAs with an area under the receiver operating characteristic curve (AUC-ROC) of 0.847. The accuracy and AUC-ROC ranges of the other methods were 57.4-70.2% and 0.575-0.704, respectively. Differences in predictive performance between qTA-based classification and the other methods were significant (p < 0.05).

CONCLUSIONS

The ML-based qTA of T2-weighted MRI is a potential non-invasive tool in predicting response to SAs in patients with acromegaly and GH-secreting pituitary macroadenoma. The method performed better than the qualitative and quantitative rSI and immunohistochemical evaluation.

KEY POINTS

• Machine learning-based texture analysis of T2-weighted MRI can correctly classify response to somatostatin analogues in more than four fifths of the patients. • Machine learning-based texture analysis performs better than qualitative and quantitative evaluation of relative T2 signal intensity and immunohistochemical evaluation. • About one third of the texture features may not be excellently reproducible, indicating that a reliability analysis is necessary before model development.

Single-stage planning for total cure of grade III-V brain arteriovenous malformations by embolization alone or in combination with microsurgical resection

PURPOSE

There are no established guidelines for treatment of Spetzler-Martin grade III-V brain arteriovenous malformations (bAVMs). The purpose of this study is to report our institutional experience in total obliteration/eradication of grade III-V bAVMs by single-stage planning of embolization combined with microsurgical resection when necessary.

METHODS

All patients harboring Spetzler-Martin (S-M) grade III-V bAVMs treated with single-stage planning between January 2006 and January 2018 were retrospectively reviewed. This treatment paradigm is applicable only to surgically accessible bAVMs and does not include deep-seated bAVMs. Indications for treatment, clinical presentation, imaging characteristics, and treatment outcomes were analyzed. Outcomes were assessed based on modified Rankin Scale.

RESULTS

A total of 31 patients were identified. Seventeen patients (54.8%) presented with hemorrhage, 10 (32.3%) with seizures, 3 (9.7%) with headaches, and 1 (3.2%) with progressive neurological deficit. Based on S-M grading system, 25 patients (80.6%) harbored grade III bAVM, 5 patients had grade IV bAVMs (16.1%), and 1 patient (3.2%) had a grade V bAVM. There were no treatment-related complications in 24/31 (77.4%) patients. Of the total of seven patients with complications, four patients had clinical deterioration. The long-term (> 6-month), non-disabling morbidity (mRS ≤ 2) rate was 6.5%. The long-term, disabling morbidity rate was 3.2% with a mortality of 3.2%. Complete angiographic obliteration was achieved in 30/31 (96.8%) patients.

CONCLUSION

Single-stage treatment strategy can be considered as an alternative to multistage embolization prior to surgery in grade III-V bAVMs. In this study, a high rate of total obliteration with relatively low rates of permanent morbidity and mortality was achieved.

Intracranial Serpentine Aneurysms: Spontaneous Changes of Angiographic Filling Pattern

BACKGROUND AND PURPOSE

Serpentine aneurysms are partially thrombosed aneurysms with an eccentrically located tortuous intra-aneurysmal vascular channel. The large size, distinctive neck anatomy, and supply of the brain parenchyma by the outflow tract pose technical challenges in treatment. The aim of this study was to discuss the endovascular treatment results and illustrate the dynamic nature of serpentine aneurysms. Spontaneous transformation of saccular and fusiform aneurysms into serpentine morphology, along with a case of serpentine-into-fusiform aneurysm transformation during follow-up, is presented.

MATERIALS AND METHODS

A retrospective analysis from 3 institutions revealed 15 patients with serpentine aneurysms who underwent diagnostic evaluation and endovascular treatment. Nine of the 15 patients underwent endovascular occlusion of the parent vessel with detachable balloon or coils. Six of the 15 patients underwent aneurysm and parent artery occlusion with coiling.

RESULTS

In 11 patients, improvement or resolution of symptoms was achieved by an endovascular approach without any treatment-related morbidity. Morbidity related to treatment in the immediate postoperative period was seen in 3 patients, with resolution of the deficits at long-term follow-up in 2 patients and persistence of a mild deficit in 1 patient. Endovascular treatment failed to achieve resolution of symptoms in a case with a basilar tip aneurysm treated by aneurysm coiling.

CONCLUSIONS

Serpentine aneurysms are dynamic structures with spontaneous transformation possible from a saccular or fusiform shape into a serpentine configuration. An endovascular approach by parent vessel occlusion or intra-aneurysmal occlusion is a successful treatment technique for serpentine aneurysms.

Intrathecal gadolinium-enhanced MR cisternography in patients with otorhinorrhea: 10-year experience of a tertiary referral center

PURPOSE

Despite a considerable amount of literature that has been published about the use of intrathecal gadolinium-enhanced MR cisternography (IGE-MRC), there is still relatively lack of evidence as to its long-term effects. Our purpose in this study was twofold: firstly, to assess the long-term safety of the IGE-MRC; secondly, to evaluate the diagnostic performance of IGE-MRC for detecting cerebrospinal fluid (CSF) leak in otorhinorrhea patients.

METHODS

We retrospectively reviewed our imaging and clinical database for the patients admitted to our department for the evaluation of their otorhinorrhea between 2008 and 2017. Two radiologists evaluated the imaging studies independently. Consensus data was used in the analysis. Medical record review and phone call were used for the long-term follow-up.

RESULTS

The retrospective review yielded 166 patients. Rhinorrhea was present in 150 (90.4%) patients and otorrhea in 16 (9.6%) patients. Overall, 67 patients (40.5% of all patients) underwent operation for repair of the CSF leak site. Beta-transferrin test was available and positive in 57 (34.3%) patients. Overall sensitivity of IGE-MRC and paranasal high-resolution CT (HRCT) was 89.3 and 72%, respectively. Within the first 24 h after the procedure, none of the patients experienced a significant complication or adverse reaction. Ninety-nine patients (59.6%) had medical record and telephone follow-up. The mean follow-up duration with call was 37.1 months. Three (3%) patients complained about severe headache 3-4 weeks after the procedure.

CONCLUSIONS

IGE-MRC is a minimally invasive and highly sensitive imaging technique. No adverse side effect during our long-term follow-up might strengthen and support the safety of IGE-MRC.

European Multicenter Study for the Evaluation of a Dual-Layer Flow-Diverting Stent for Treatment of Wide-Neck Intracranial Aneurysms: The European Flow-Redirection Intraluminal Device Study

BACKGROUND AND PURPOSE

Endoluminal reconstruction with flow-diverting stents represents a widely accepted technique for the treatment of complex intracranial aneurysms. This European registry study analyzed the initial experience of 15 neurovascular centers with the Flow-Redirection Intraluminal Device (FRED) system.

MATERIALS AND METHODS

Consecutive patients with intracranial aneurysms treated with the FRED between February 2012 and March 2015 were retrospectively reviewed. Complications and adverse events, transient and permanent morbidity, mortality, and occlusion rates were evaluated.

RESULTS

During the defined study period, 579 aneurysms in 531 patients (median age, 54 years; range, 13-86 years) were treated with the FRED. Seven percent of patients were treated in the acute phase (≤3 days) of aneurysm rupture. The median aneurysm size was 7.6 mm (range, 1-36.6 mm), and the median neck size 4.5 mm (range, 1-30 mm). Angiographic follow-up of >3 months was available for 516 (89.1%) aneurysms. There was progressive occlusion witnessed with time, with complete occlusion in 18 (20%) aneurysms followed for up to 90 ± 14 days, 141 (82.5%) for 180 ± 20 days, 116 (91.3%) for 1 year ± 24 days, and 122 (95.3%) aneurysms followed for >1 year. Transient and permanent morbidity occurred in 3.2% and 0.8% of procedures, respectively. The overall mortality rate was 1.5%.

CONCLUSIONS

This retrospective study in real-world patients demonstrated the safety and efficacy of the FRED for the treatment of intracranial aneurysms. In most cases, treatment with a single FRED resulted in complete angiographic occlusion at 1 year.

Is there an association between flow diverter fish mouthing and delayed-type hypersensitivity to metals?-a case-control study

PURPOSE

Flow diverters are increasingly used in the treatment of complex and giant intracranial aneurysms. However, they are associated with complications like late aneurysmal rupture. Additionally, flow diverters show focal structural decrease in luminal diameter without any intimal hyperplasia. This resembles a "fish mouth" when viewed en face. In this pilot study, we tested the hypothesis of a possible association between flow diverter fish-mouthing and delayed-type hypersensitivity to its metal constituents.

METHODS

We retrospectively reviewed patient records from our center between May 2010 and November 2015. A total of nine patients had flow diverter fish mouthing. A control group of 25 patients was selected. All study participants underwent prospective patch test to detect hypersensitivity to flow diverter metal constituents. Analysis was performed using logistic regression analysis and Wilcoxon sign rank sum test. Univariate and multivariate analyses were performed to test variables to predict flow diverter fish mouthing.

RESULTS

The association between flow diverter fish mouthing and positive patch test was not statistically significant. In multivariate analysis, history of allergy and maximum aneurysm size category was associated with flow diverter fish mouthing. This was further confirmed on Wilcoxon sign rank sum test.

CONCLUSION

The study showed statistically significant association between flow diverter fish mouthing and history of contact allergy and a small aneurysmal size. Further large-scale studies are needed to detect a statistically significant association between flow diverter fish mouthing and patch test. We recommend early and more frequent follow-up imaging in patients with contact allergy to detect flow diverter fish mouthing and its subsequent evolution.

Multicenter Experience with FRED Jr Flow Re-Direction Endoluminal Device for Intracranial Aneurysms in Small Arteries

BACKGROUND AND PURPOSE

Flow diverters are emerging as an endovascular treatment alternative for proximally located intracranial aneurysms. However, treatment of aneurysms at and beyond the circle of Willis is not well-established. We assessed the clinical safety and efficacy of the Flow Re-Direction Endoluminal Device Jr (FRED Jr) dedicated to small-vessel diameters between 2.0 and 3.0 mm.

MATERIALS AND METHODS

This was a multicenter observational clinical study of 42 patients with 47 aneurysms treated by a flow-direction technique with the FRED Jr. The primary end point for clinical safety was the absence of death, major or minor stroke, and TIA. The primary end point for treatment efficacy was complete and near-complete occlusion according to the O'Kelly-Marotta grading scale at follow-up after 1, 6, and 12 months.

RESULTS

The FRED Jr deployment was technically successful in all cases. In 39/42 (93%) patients, the primary safety end point was reached; in the 3 remaining patients, 1 disabling ischemic stroke, 1 minor stroke with complete recovery at discharge, and 1 TIA were observed. Two asymptomatic, completely reversible side-branch occlusions occurred. Angiographic (DSA or flat panel CT) and clinical follow-up were available after 1 month in 41/47 (87%), 6 months in 27/47 (57%), and 12 months in 11/47 (23%) aneurysms. The primary efficacy end point was reached at 1 month in 27/41 (66%), at 6 months in 21/27 (78%), and at 12 months in 11/11 (100%) aneurysms.

CONCLUSIONS

Deployment of the FRED Jr is safe and effective in the treatment of intracranial aneurysms located in small vessels.

European consensus conference on unruptured brain AVMs treatment (Supported by EANS, ESMINT, EGKS, and SINCH)

In December of 2016, a Consensus Conference on unruptured AVM treatment, involving 24 members of the three European societies dealing with the treatment of cerebral AVMs (EANS, ESMINT, and EGKS) was held in Milan, Italy. The panel made the following statements and general recommendations: (1) Brain arteriovenous malformation (AVM) is a complex disease associated with potentially severe natural history; (2) The results of a randomized trial (ARUBA) cannot be applied equally for all unruptured brain arteriovenous malformation (uBAVM) and for all treatment modalities; (3) Considering the multiple treatment modalities available, patients with uBAVMs should be evaluated by an interdisciplinary neurovascular team consisting of neurosurgeons, neurointerventionalists, radiosurgeons, and neurologists experienced in the diagnosis and treatment of brain AVM; (4) Balancing the risk of hemorrhage and the associated restrictions of everyday activities related to untreated unruptured AVMs against the risk of treatment, there are sufficient indications to treat unruptured AVMs grade 1 and 2 (Spetzler-Martin); (5) There may be indications for treating patients with higher grades, based on a case-to-case consensus decision of the experienced team; (6) If treatment is indicated, the primary strategy should be defined by the multidisciplinary team prior to the beginning of the treatment and should aim at complete eradication of the uBAVM; (7) After having considered the pros and cons of a randomized trial vs. a registry, the panel proposed a prospective European Multidisciplinary Registry.

Detection of wall and neck calcification of unruptured intracranial aneurysms with flat-detector computed tomography

OBJECT

Microsurgical clipping is a widely used surgical technique in intracranial aneurysm treatment. It can be difficult in large sized aneurysms, and those with wide necks, thick walls and calcification located in the vicinity of the neck. This study reviewed calcification of the intracranial aneurysm wall and its relation to patient age, gender, location and size of the aneurysm. A possible cut-off value after which the aneurysm calcification rate increases was also investigated to classify patients' risk factors for microclipping.

METHODS

A retrospective review of all unruptured intracranial aneurysms that underwent digital subtraction angiography at a single centre was performed. Flat-detector computed tomography images of the aneurysm were reviewed for aneurysm location, size and calcification. The independent samples t test and χ(2) test were used to show the relation between aneurysm wall calcification and patient age, gender, aneurysm localisation and size.

RESULTS

None of the reviewed factors were statistically significantly related to aneurysm calcification except aneurysm size (P < 0.01). Receiver operating characteristic curves showed aneurysms greater than 10.5 mm could be predicted to be calcified with a sensitivity of 80% and specificity of 63%.

CONCLUSION

In this study, the presence of calcification was related to aneurysm size. Larger aneurysms were more likely to be calcified. Aneurysms greater than 10.5 mm should be further investigated with a modality such as flat-detector computed tomography to show the calcification in detail, especially if microclipping is considered.

Endovascular Management of Superior Cerebellar Artery Aneurysms: Mid and Long-Term Results

AIM

Superior cerebellar artery (SCA) aneurysms are uncommon vascular lesions, thus data about their presentation and clinical management are limited. Our aim was to determine clinical presentation, angiographic findings and mid and long-term clinical and imaging results of endovascular treatment of 49 patients with SCA aneurysm.

MATERIAL AND METHODS

Forty-nine patients with SCA aneurysms underwent endovascular treatment (25 female, 24 male; mean age 46.7 years; range, 21-79 years) in our institution. Both aneurysms arising at the origin of SCA and peripheral SCA aneurysms were included to our retrospective study. 73.5% of the patients were presented with subarachnoid hemorrhage. Forty-two of 49 (85.7%) aneurysms were located in the origin of SCA. Mean aneurysm size was 6.5 mm (range 2-16 mm).

RESULTS

Forty-seven (95.9%) of the aneurysms were coiled with detachable coils. In two peripheral aneurysms, liquid embolic agent was used. Overall control angiographic occlusion rates were as follows: 87.5% (34/40) total occlusion and 12.5% (6/40) dog-ear remnant. All peripheral SCA aneurysms were occluded with the parent artery. Procedure related mortality was seen in one patient (2%) due to the rupture of another aneurysm. There was no procedure related permanent morbidity.

CONCLUSION

Endovascular treatment is an effective and safe option in both peripheral and proximal SCA aneurysms.

Primary diffuse leptomeningeal gliomatosis mimicking tuberculous meningitis

Primary diffuse leptomeningeal gliomatosis is a disease with an aggressive course that can result in death. To date, 82 cases have been reported. Here, the case of a 3-year-old male patient presenting with strabismus, headache, and restlessness is reported. Physical examination revealed paralysis of the left abducens nerve, neck stiffness, and bilateral papilledema. Tuberculous meningitis was tentatively diagnosed, and antituberculosis treatment was initiated when cranial imaging revealed contrast enhancement around the basal cistern. Craniocervical magnetic resonance imaging (MRI) was performed when there was no response to treatment, and it revealed diffuse leptomeningeal contrast enhancement around the basilar cistern, in the supratentorial and infratentorial compartments, and in the spinal region. Primary diffuse leptomeningeal gliomatosis was diagnosed by a meningeal biopsy.

Use of buddy wire to facilitate Y-configured stent placement in middle cerebral artery bifurcation aneurysms with daughter branches arising from the sac: a technical note

BACKGROUND AND IMPORTANCE

Endovascular treatment of geometrically complex bifurcation aneurysms using a standard Y-configured stenting technique might be extremely difficult, particularly in aneurysms with daughter branches that acutely arise from the aneurysm sac itself. In those cases, deployment of the second stent through interstices of the first stent could be troublesome because of untoward angular changes in the vascular bifurcation prompted by angular changes resulting from placement of the first stent. Here, we describe a novel application of the buddy wire technique to facilitate Y-configured stenting in middle cerebral artery (MCA) bifurcation aneurysms with unfavorable anatomic configuration.

CLINICAL PRESENTATION

A 60-year-old man with a left-sided MCA bifurcation aneurysm was treated using the buddy wire technique. In addition to the standard Y-configured stenting procedure, we also inserted a 0.014-inch exchange microguidewire into the superior daughter branch, which more acutely emanated from the sac, to attain a favorable bifurcation configuration before deployment of the stents in the Y configuration. The new technique was successful, and the postprocedural course of the treatment was uneventful.

CONCLUSION

Use of a buddy wire in MCA bifurcation aneurysms with unfavorable anatomic configurations may be a promising method to facilitate Y-configured stent placement.

Flow Re-direction Endoluminal Device in treatment of cerebral aneurysms: initial experience with short-term follow-up results

Object

Flow diverter (FD) stents are relatively new and important devices in the treatment of cerebral aneurysms. The Flow Re-Direction Endoluminal Device has been recently released for clinical use. The authors' aim in this paper is to report their initial single-center FRED experience with short-term results.

Methods

Between February 2012 and May 2013, 33 patients with 37 aneurysms (35 unruptured and 2 previously ruptured aneurysms) were treated with the FRED. Clinical and radiological data of the patients were retrospectively reviewed.

Results

In all patients only 1 device was used without any additional device or material, such as a stent or coil. All procedures were successfully performed. The procedural complication rate was 3% (1 of 33). Thirty patients underwent clinical and radiological follow-up. During the follow-up period, changes in stent morphology, such as “fish mouth” and “foreshortening” phenomena, occurred in 5 patients. The mortality and permanent morbidity rates were 0%. The complete occlusion rates were 32% (6 of 19) at 0–1 month, 67% (8 of 12) at 2–3 months, 80% (4 of 5) at 4–6 months, and 100% (8 of 8) at 7–12 months. The rates for some aneurysms were assessed at more than one time point.

Conclusions

The FRED has an ability to serve neurointerventionalists in the treatment of cerebral aneurysms with its different technical advantages. The occlusion rates with FRED are similar to those with other FD devices. However, these short-term results need to be confirmed with mid- and long-term follow-up results of multicenter large series.