Neurointerventional Procedures Research Articles

Outcome of intracranial flow diversion according to the antiplatelet regimen used: a systematic review and meta-analysis

BackgroundThromboembolic complications are not uncommon in patients undergoing neurointerventional procedures. The use of flow diverting stents is associated with higher risks of these complications despite current dual antiplatelet regimens.ObjectiveTo explore...

Practical Dose Parameter Values for the Prediction of the Adverse Effect of Neurointerventional Radiation: Relationship Between the Dose Parameters and Temporary Alopecia After Intracranial Coil Embolization

To present values for the dose parameters predictive of alopecia as an adverse effect induced by neuroembolization using a biplane fluoroscopy. This study included a total of 151 patients (52men, mean age of 55.1 ± 12.2 years) treated for intracranial neuroembolization between 2014 to 2018 with the following criteria: 1) obtainable dose report with digital subtraction angiographic image records, 2) no history of radiation exposure 6 months prior to the first procedure, and 3) and clinical follow-up performed through 12 months following the procedure. Patients were divided into 2 groups according to their presentation of alopecia during the follow-up period. Eighteen (11.9%) patients developed alopecia 10 to 30 days after the procedure (average: 18.5 ± 5.3 days). Sixteen (88.9%) patients in the alopecia group were affected by projection of the A-plane fluoroscopy. Area under the receiver operating characteristic analysis curves of 0.865 (P= 0.000) and 0.831 (P= 0.000) were used to compute the optimal A-plane dose area product (255.4 Gy-cm2; sensitivity: 0.875; specificity: 0.805; Youden J= 0.682) and cumulative dose (4437.5 mGy; sensitivity, 0.750; specificity, 0.805; Youden J= 0.556) cutoff values, respectively, capable of distinguishing patients with alopecia (n= 16) from subtotal patients (n= 149). The dose area product and the cumulative dose may be useful, intuitive factors for predicting the adverse effects of the neurointerventional radiation. Further multicenter research should be performed to confirm the efficacy and utility of the reference values of dose area product and cumulative dose for preventing excessive irradiation during neurointerventional procedures.

An Analysis of Telephonic Pre-PCP visit Pharmacist Interventions in Appropriate Medication Use for Diabetes Patients

The role of interventional neuroradiology has expanded in the past decades as the safety of cerebral angiogram has improved. Not only is the use of diagnostic angiography increasing, the role of intervention in neurologic injury has increased dramatically as well. Angiography is not solely a means of diagnosis; an increasing number of interventions are now being used to treat injuries such as acute stroke, intracranial stenosis, cerebral aneurysms, and cerebral vasospasm through a variety of modalities including intraarterial medications, stents, and embolizations. Even though the safety of cerebral angiography and neurointerventional procedures has improved, the most common neurologic complication remains stroke. This chapter is designed to serve as a primer in clinical neurologic examination.

Influence of CYP450 Enzymes, CES1, PON1, ABCB1, and P2RY12 Polymorphisms on Clopidogrel Response in Patients Subjected to a Percutaneous Neurointervention

PurposeClopidogrel is a thienopyridine prodrug that inhibits platelet aggregation. It is prescribed to prevent atherothrombotic and thromboembolic events in patients receiving a stent implant in carotid, vertebral, or cranial arteries. The influence of cytochrome P-450 (CYP) 2C19 on the response to clopidogrel has been widely studied; however, the effect of other genes involved in clopidogrel absorption and metabolism has not been established in this cohort of patients. MethodsThis observational retrospective study assessed the antiplatelet response and the prevalence of hemorrhagic or ischemic events after percutaneous neurointervention in clopidogrel-treated patients, related to 35 polymorphisms in the genes encoding the clopidogrel-metabolizing enzymes (CYP2C19, CYP1A2, CYP2B6, CYP2C9, CYP2C9, CYP3A4, CYP3A5, carboxylesterase-1 [CES1], and paraoxonase-1 [PON1]), P-glycoprotein transporter (ABCB1), and platelet receptor P2Y12. Polymorphisms were analyzed by quantitative real-time polymerase chain reaction and matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry. Antiplatelet response was documented with the VerifyNow system (Accriva, San Diego, California). FindingsWe confirmed that CYP2C19 is the most important enzyme involved in clopidogrel response. The carriage of the CYP2C19*2 allele was strongly associated with hyporesponse to clopidogrel, while the CYP2C19*17 allele was a protective factor for the development of ischemic events (odds ratio = 0.149; P = 0.002) but a risk factor for bleeding (odds ratio = 3.60; P = 0.038). Patients carrying ABCB1 mutated alleles showed lower aggregation values, suggesting that clopidogrel absorption is influenced by P-glycoprotein. In fact, the percentage of responders was significantly higher in the group carrying the mutated haplotype compared to the wild type (80.8% vs 43.3%; P = 0.009). Patients with the CES1 G143E C/T genotype showed a considerably lower, aggregation value versus wild-type patients, although the difference was not significant likely due to the small sample size (59.0 [21.2] vs 165.2 [86.0] PRU; P = 0.084), which suggests an increased active metabolite formation. No relationship was found between polymorphisms in other CYP genes, PON1, or P2RY12 and response to clopidogrel in patients subjected to neurointervention procedures. ImplicationsTherapeutic guidelines recommend that CYP2C19 intermediate and poor metabolizers with acute coronary syndromes undergoing percutaneous coronary intervention receive an alternative antiplatelet therapy; however, genotype-guided therapy is not a standard recommendation for neurovascular conditions. This is the first study to carry out a joint analysis of CYP2C19 and other genes involved in clopidogrel treatment in patients receiving percutaneous neurointervention. Our findings support routine genotyping in clopidogrel-treated patients. Moreover, we encourage considering an alternative antiplatelet therapy in CYP2C19 intermediate, poor and ultrarapid metabolizers. Additionally, ABCB1 polymorphisms could be considered for a better pharmacogenetic approach.

DNA damage and gene expression changes in patients exposed to low-dose X-radiation during neuro-interventional radiology procedures

Interventional radiology-based imaging is the preferred choice for diagnosis and therapy of many complex diseases, despite possible adverse effects of the radiation exposures. We have measured induced DNA damage and changes in gene expression in relation to entrance surface dose (ESD) in peripheral blood samples of patients (n = 51) who underwent neuro-interventional radiological procedures. The ESD values, measured by thermoluminescence dosimetry, were 4.9–273 mGy (forehead), 14–398 mGy (eyes), 8–433.3 mGy (shoulders), and 4.7–242.5 mGy (thyroid). The in-built recorded Dose Area Product (DAP) values were 74.61–558.55 and 13.17–2825.12 Gy*cm2 for diagnostic and therapeutic procedures, respectively. The mean fluorescence intensity (MFI) on the phosphorylation of γ-H2AX and p53ser−15 was higher in samples obtained post-exposure vs. pre-exposure. However, the increase was statistically significant only for p53ser−15 (P < 0.01). Consistent with γ-H2AX, CDKN1A, FDXR, BAX, DDB2, SESN1, BCL2, MDM2, TNFSF10B, and PCNA showed (non-significant) decreased expression while GADD45A, ATM, and TNFSF9 showed (non-significant) increased expression. Our results suggest that most of the patients had increased DNA damage and altered gene expression after receiving relatively low doses of ionising radiation. This implies that these procedures should be carried out at the lowest possible doses of radiation that do not compromise image quality.

Image Quality of Low-Dose Cerebral Angiography and Effectiveness of Clinical Implementation on Diagnostic and Neurointerventional Procedures for Intracranial Aneurysms.

Awareness of the potential for exposure to high doses of radiation from interventional radiologic procedures has increased. The purpose of this study was to evaluate image quality and dose reduction of low-dose cerebral angiography during diagnostic and therapeutic procedures for intracranial aneurysms. A retrospective review of 1137 prospectively collected patients between January 2012 and June 2014 was performed. Beginning in April 2013, a dose-reduction strategy was implemented. Subjective image-quality assessment of 506 standard and 540 low-dose cerebral angiography images was performed by 2 neuroradiologists using a 5-point scale and was tested using noninferiority statistics. Radiation dose-area product and air kerma of 1046 diagnostic and 317 therapeutic procedures for intracranial aneurysms were analyzed and compared between groups before (group 1) and after (group 2) clinical implementation of a dose-reduction strategy. The image quality of the low-dose cerebral angiography was not inferior on the basis of results from the 2 readers. For diagnostic cerebral angiography, the mean dose-area product and air kerma were 140.8 Gy×cm2 and 1.0 Gy, respectively, in group 1 and 82.0 Gy×cm2 and 0.6 Gy in group 2 (P < .001, P < .001). For the neurointerventional procedure, the mean dose-area product and air kerma were 246.0 Gy×cm2 and 3.7 Gy, respectively, in group 1 and 169.8 Gy×cm2 and 3.3 Gy in group 2 (P < .001, P = .291). With low-dose cerebral angiography, image quality was maintained, and implementation of dose-reduction strategies reduced radiation doses in patients undergoing diagnostic and neurointerventional procedures for intracranial aneurysms.

Radiation exposure during neurointerventional procedures in modern angiographic systems: A single center experience

Background/Aim. Interventional neuroradiology procedures expose patients to ionizing radiation. The aim of this study was to assess doses received by patients during interventional neuroradiology procedures and to establish dose range with an estimate of risk from adverse consequences of irradiation. Methods. Our study describes series of patients submitted to diagnostic and/or therapeutic procedures at the Department of Interventional Neuroradiology, Clinical Center Kragujevac, Serbia, from December 1, 2014 to December 1, 2016. The following variables were considered for this study: kerma-area product, air kerma and fluoroscopy exposure time; peak skin dose and effective dose calculated from the kerma-area product. Results. Median kerma-area product was 87.802 Gy?cm2, 78.567 Gy?cm2, 117.626 Gy?cm2; effective dose was 12.731 mSv, 11.392 mSv, 17.056 mSv; peak skin dose was 0.456 Gy, 0.409 Gy, 0.612 Gy, and estimated brain dose was 254.62 mGy, 227.84 mGy, 341.12 mGy, for diagnostic, therapeutic and combined procedures, respectively. Conclusion. Interventional neuroradiology procedures show significant variability in radiation dose, due to patient constitution, radiologist expertise and equipment factors. Knowing the doses can have a great benefit for patients and medical and paramedical stff in terms of prevention of possible deterministic and stochastic effects of the radiation.

The pCONUS HPC: 30-Day and 180-Day In Vivo Biocompatibility Results

BackgroundEndovascular stents are commonly used during neurointerventional procedures; however, the concomitant use of dual anti-platelet treatment (DAPT) can limit their use. There is a need to develop stent coatings that mitigate requirement for DAPT.MethodsThe hydrophilic polymer coating is a novel glycan-based multilayer polymer that inhibits platelet adhesion. After Institutional Animal Care and Use Committee approval, 18 New Zealand white rabbits (mean weight 4.02 ± 0.51 kg) were commenced on DAPT (ASA 10 mg/kg/day and clopidogrel 10 mg/kg/day). A bare nitinol pCONUS and coated pCONUS HPC were implanted into the common carotid arteries of each rabbit. Histological examinations were performed at 30 days (n = 9) and 180 days (n = 8) to assess the acute and chronic inflammatory reactions to the pCONUS HPC. Wilcoxon/Kruskal–Wallis and ANOVA were used with p value < 0.05 considered as significant.ResultsThere is no statistically significant difference in inflammation within the intima/media or adventitia at 30 days (p = 0.3901 and p = 1, respectively) or at 180 days (p = 0.144 and p = 1, respectively) between pCONUS and pCONUS HPC cohorts. There is no significant difference in the presence of granulomas or giant cells between the cohorts at either 30 days (p = 1 and p = 0.8363) or 180 days (p = 1.00 and p = 0.149). At 30 days and 180 days, there was near-complete endothelialisation of the stent struts and no significant difference between the pCONUS or pCONUS HPC (p = 0.7832 and p = 0.334, respectively).ConclusionpCONUS HPC stents do not elicit an acute or chronic inflammatory response in vivo with no significant difference in the tissue response to bare nitinol pCONUS stents or pCONUS HPC stents.

Neurointerventional Procedural Complications in a Growing Canadian Regional Stroke Center: Single Hospital Experience Analysis in the Context of Recommended Case Volumes

Evidence continues to emerge regarding the inverse relationship between high neurointerventional case volume and complication rates, leading several medical/surgical societies to recommend minimum volumes for specific procedures. Recent data suggest few centers are meeting these requirements. We report a single center's neurointerventional complication rates with associated case volumes, along with a review of the literature. A retrospective cohort review of all consecutive patients undergoing diagnostic catheter cerebral angiography and/or neurointerventional procedures between January 1, 2013, and March 1, 2018, was undertaken. No diagnostic or interventional procedures were excluded. All major and minor complications were recorded. A total of 1000 procedures (463 diagnostic cerebral angiograms and 537 neurointerventional procedures) were completed. Of the neurointerventional procedures, 216 (40%) were endovascular thrombectomy, 170 (32%) were aneurysmal embolization, and 48 (9%) were carotid stenting. The mean and median age was 60 years. There were 460 women and 540 men. The total number of major complications for diagnostic angiography, endovascular thrombectomy, ruptured aneurysm embolization, unruptured aneurysm embolization, and carotid artery stenting were 4 (0.9%), 4 (1.9%), 10 (11%), 4 (5.4%), and 3 (6.3%), respectively. We provided a single-center experience of the relationship between neurointerventional procedural case volume and complication rates in the growth phase of our center's establishment. We demonstrated that as our center was being developed, specific procedural staffing measures allowed proficiency maintenance, acquisition of new techniques, and complication avoidance, whereas specific case volumes crossed the suggested thresholds as defined in the literature.

Use of the Apollo detachable-tip microcatheter for endovascular embolization of arteriovenous malformations and arteriovenous fistulas.

Liquid embolic agents have revolutionized endovascular management of arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs). Nonetheless, since 2005, the US FDA has received more than 100 reports of microcatheter breakage or entrapment related to Onyx embolization, including 9 deaths. In 2014, the Apollo detachable-tip microcatheter became the first of its kind available in the US. Since then, few reports on its safety have been published. The authors conducted a retrospective review of endovascular cases by searching the patient databases at 2 tertiary cerebrovascular centers (Barrow Neurological Institute and University of Pittsburgh Medical Center). Patients who underwent endovascular embolization of an AVM or AVF using the Apollo microcatheter were identified. Patient demographics and lesion characteristics were collected. The authors analyzed Apollo-specific endovascular variables, such as number of microcatheterizations, sessions, and pedicles embolized; microcatheter tip detachment status; obliteration rate; and endovascular- and microcatheter-related morbidity and mortality. From July 2014 to October 2016, a total of 177 embolizations using the Apollo microcatheter were performed in 61 patients (mean age 40.3 years). The most frequent presentation was hemorrhage (22/61, 36.1%). Most lesions were AVMs (51/61, 83.6%; mean diameter 30.6 mm). The mean Spetzler-Martin grade was 2.4. Thirty-nine (76.5%) of 51 patients with AVMs underwent resection. Microcatheterization was successful in 172 pedicles. Most patients (50/61, 82%) underwent a single embolization session. The mean number of pedicles per session was 2.5 (range 1-7). Onyx-18 was used in 103 (59.9%), N-butyl cyanoacrylate (NBCA) in 44 (25.6%), and Onyx-34 in 25 (14.5%) of the 172 embolizations. In 45.9% (28/61) of the patients, lesion obliteration of 75% or greater was achieved. Tip detachment occurred in 19.2% (33/172) of microcatheters. Fifty-three (86.9%) of the 61 patients who underwent embolization with the Apollo microcatheter had good functional outcomes (modified Rankin Scale score 0-2). No unintended microcatheter fractures or related morbidity was observed. One patient died of intraprocedural complications unrelated to microcatheter selection. In the univariate analysis, microcatheter tip detachment (p = 0.12), single embolized pedicles (p = 0.12), and smaller AVM nidus diameter (p = 0.17) correlated positively with high obliteration rates (> 90%). In the multivariate analysis, microcatheter tip detachment was the only independent variable associated with high obliteration rates (OR 9.5; p = 0.03). The use of the Apollo detachable-tip microcatheter for embolization of AVMs and AVFs is associated with high rates of successful catheterization and obliteration and low rates of morbidity and mortality. The microcatheter was retrieved in all cases, even after prolonged injections in distal branch pedicles, often with significant reflux. This study represents the largest case series on the application of the Apollo microcatheter for neurointerventional procedures.

Infection risk in endovascular neurointerventions: a comparative analysis of 549 cases with and without prophylactic antibiotic use.

A systematic analysis on the utility of prophylactic antibiotics for neuroendovascular procedures has not been performed. At the authors' institution there is a unique setup to address this question, with some attending physicians using prophylactic antibiotics (cefazolin or vancomycin) for all of their neurointerventions while others generally do not. The authors performed a retrospective review of the last 549 neurointerventional procedures in 484 patients at Tisch Hospital, NYU Langone Medical Center. Clinical and radiological data were collected for analysis, including presence of prophylactic antibiotic use, local or systemic infection, infection laboratory values, and treatment. Overall, 306 aneurysms, 117 arteriovenous malformations/arteriovenous fistulas, 86 tumors, and 40 vessel stenosis/dissections were treated with coiling (n = 109), Pipeline embolization device (n = 197), embolization (n = 203), or stenting (n = 40). Antibiotic prophylaxis was used in 265 of 549 cases (48%). There was no significant difference between patients with or without antibiotic prophylaxis in sex (p = 0.48), presence of multiple interventions (p = 0.67), diseases treated (p = 0.11), or intervention device placed (p = 0.55). The mean age of patients in the antibiotic prophylaxis group (53.4 years) was significantly lower than that of the patients without prophylaxis (57.1 years; p = 0.014). Two mild local groin infections (0.36%) and no systemic infections (0%) were identified in this cohort, with one case in each group (1/265 [0.38%] vs 1/284 [0.35%]). Both patients recovered completely with local drainage (n = 1) and oral antibiotic treatment (n = 1). The risk of infection associated with endovascular neurointerventions with or without prophylactic antibiotic use was very low in this cohort. The data suggest that the routine use of antibiotic prophylaxis seems unnecessary and that to prevent antibiotic resistance and reduce costs antibiotic prophylaxis should be reserved for selected patients deemed to be at increased infection risk.

Abstract TP188: Trends in Costs Associated With Endovascular and Surgical Treatments for Unruptured Intracranial Aneurysm Among Commercially Insured Patients

Objectives: Limited studies have examined economic outcomes of endovascular coiling (EVC) and/ or surgical clipping (SC) for unruptured intracranial aneurysm (UIA) from a payer perspective. This study evaluated trends in payments for index admission and 365-day follow-up (including index admission) among UIA patients treated with EVC or SC. Methods: A retrospective analysis of Truven MarketScan® Commercial Claims and Encounters (CCAE) database was conducted. The study sample included patients aged ≥ 18 years with a diagnosis of UIA who underwent EVC or SC between 2011 and 2016 (index hospitalization). The following exclusion criteria were applied: patients with a history of subarachnoid hemorrhage (SAH) or EVC/SC treatment in 12 months baseline; concurrent diagnosis of SAH during index hospitalization or lack of continuous enrollment in 12 months baseline period. Using Mann-Kendall test, we examined trends in payments for index admission and 365-day all-cause healthcare utilization (medical services and prescription). All costs were adjusted to 2016 US dollar. Results: A total of 3,294 patients met the eligibility criteria. The mean age of patients was 52.53 years (SD= 8.64) and 76.56% were female. The proportions of patients treated with EVC (vs. SC) increased from 67.80% in 2011 to 75.84% in 2016 (p= 0.01). The average index admission cost was $54,853 and the mean 365-day follow-up cost was $89,398. Mean index admission cost was $52,163 in 2011 and $64,193 in 2016 (p= 0.19). However, mean 365-day all-cause follow-up costs increased from $87,741 in 2011 to $94,096 in 2016 (p= 0.04). Conclusions: The 365-day all-cause follow-up costs associated with endovascular and surgical treatment among UIA patients increased significantly over the study period. There is significant economic burden for UIA patients undergoing neurointerventional procedures.

Transradial approach for flow diversion treatment of cerebral aneurysms: a multicenter study

BackgroundThe transradial approach (TRA) to endovascular procedures decreases access site morbidity and mortality in comparison with the traditional transfemoral technique (TFA). Despite its improved safety profile, there is a concern...

Feasibility of Using Neck Extension to Overcome a Difficult Aortic Arch and Gain Access to the Carotid Artery

The purpose of this study was to investigate neck movement and various conditions of the aortic arch that may hinder access to the carotid artery during neurointerventional procedures. We reviewed 230 patients who underwent internal carotid artery angiography between February 2016 and October 2016. Use of a Davis catheter (DC) was first attempted and if not possible, movement (right, left, flexion, and extension) of the patient's head was tried before catheter exchange. We analyzed the success rate after neck motion in relation to various aortic arch factors. Only extension of the patient's neck was effective. Of the 209 patients with right side angiography, 23 had failed access with a DC, but neck extension was effective in 3 patients (13%). Failure to insert a DC was significantly correlated with age, male sex, acute angle, arch elongation, aortic calcification, and carotid artery angulation on the right side, whereas access was not gained in 24 out of 208 patients who underwent left side angiography, and neck extension was successful in 7 patients (29.2%). Also, significant factors determining the catheter exchange were age, male sex, acute angle, arch elongation, and aortic calcification.In the DC access failure group, neck extension was significantly more effective for younger aged patients (P= 0.011). Factors such as older age, acute arch angle, higher elongation type, arch calcification, and carotid artery angulation were verified as factors affecting access by a simple catheter; however, neck extension was shown to facilitate access in about 10%-30% of patents.

Variability of Platelet Reactivity on Antiplatelet Therapy in Neurointervention Procedure.

As more intracranial aneurysms and other cerebrovascular pathologies are treated with neurointervention procedure, thromboembolic events that frequently lead to serious neurological deficit or fatal outcomes are increasing. In order to prevent the thromboembolic events, antiplatelet therapy is used in most procedures including coil embolization, stenting, and flow diversion. However, because of variable individual pharmacodynamics responses to antiplatelet drugs, especially clopidogrel, it is difficult for clinicians to select the adequate antiplatelet regimen and its optimal dose. This article reviews the neurointervention literature related to antiplatelet therapy and suggests a strategy for tailoring antiplatelet therapy in individual patients undergoing neurointervention based on the results of platelet function testing.

High-Definition Zoom Mode, a High-Resolution X-Ray Microscope for Neurointerventional Treatment Procedures: A Blinded-Rater Clinical-Utility Study.

Quality of visualization of treatment devices during critical stages of endovascular interventions, can directly impact their safety and efficacy. Our aim was to compare the visualization of neurointerventional procedures and treatment devices using a 194-μm pixel flat panel detector mode and a 76-μm pixel complementary metal oxide semiconductor detector mode (high definition) of a new-generation x-ray detector system using a blinded-rater study. Deployment of flow-diversion devices for the treatment of internal carotid artery aneurysms was performed under flat panel detector and high-definition-mode image guidance in a neurointerventional phantom simulating patient cranium and tissue attenuation, embedded with 3D-printed intracranial vascular models, each with an aneurysm in the ICA segment. Image-sequence pairs of device deployments for each detector mode, under similar exposure and FOV conditions, were evaluated by 2 blinded experienced neurointerventionalists who independently selected their preferred image on the basis of visualization of anatomic features, image noise, and treatment device. They rated their selection as either similar, better, much better, or substantially better than the other choice. Inter- and intrarater agreement was calculated and categorized as poor, moderate, and good. Both raters demonstrating good inter- and intrarater agreement selected high-definition-mode images with a frequency of at least 95% each and, on average, rated the high-definition images as much better than flat panel detector images with a frequency of 73% from a total of 60 image pairs. Due to their higher resolution, high-definition-mode images are sharper and visually preferred compared with the flat panel detector images. The improved imaging provided by the high-definition mode can potentially provide an advantage during neurointerventional procedures.

Endovascular Retrieval of Dislodged Neurovascular Devices with a Stentriever: Case Series and Technical Review

Endovascular treatment of neurovascular disorders is now well established as effective and safe; however, the nature of the intracranial vasculature poses unique challenges. The unintentional dislodgement or fracture of a device and its migration within cerebral vessels is a complication with serious potential morbidity that must be managed urgently. In this series, the authors describe 7 cases of a stentriever being used to remove foreign objects from within the cerebral vasculature. A retrospective search of all interventional neurovascular procedures performed in 2017 at a tertiary metropolitan hospital was performed to identify cases of dislodged devices. Five dislodged endovascular coils, 1 microcatheter, and 1 fractured stentriever were technically successfully retrieved. In 6 of the cases, the foreign object was successfully removed with a stentriever alone, whereas 1 case used a J-tip wire and a "J-tip flick" to manipulate the coil and facilitate retrieval. Stentrievers, particularly when used alone, confer the advantages of speed, cost, as well as being tailor-made for cerebral vessels. They also allow continuous blood flow when deployed, a critical advantage when considering cerebral perfusion. Critical techniques include the gradual deployment of the stentriever alongside the foreign object to allow its entanglement and partial resheathing, so that the foreign object can become pinned within the microcatheter. Stentrievers do remain limited by vessel caliber and are less able to entangle larger, stiffer devices. The migration of foreign devices during neurointerventional procedures is a serious complication requiring urgent treatment. This case series highlights the efficacy and advantages of using a stentriever and suggests its consideration as a first-line technique in recovering dislodged foreign bodies in the cerebral vasculature.

A Case of Neonate with Vein of Galen Malformation Refractory to Weaning Attempts from Mechanical Ventilation Managed Successfully with Noninvasive Ventilation

AbstractWeaning of patients with vein of Galen malformations (VOGM) from mechanical ventilation can be challenging in the postprocedure period due to underlying high-output cardiac failure and the fluid overload caused by the neurointervention procedure. We present the case of a neonate with VOGM who was refractory to multiple weaning attempts from mechanical ventilation and was successfully managed with noninvasive ventilation (NIV). NIV can be safely used as a method of weaning, post mechanical ventilation in this subset of patients. The use of NIV will facilitate successful weaning and reduce the incidence of extubation failure in neonates with VOGM in cardiac failure.

Patient Radiation Dose in Neurointerventional Radiologic Procedure: A Tertiary Care Experience.

PurposeNeurointerventional radiology procedures often require a long time to perform. Patient radiation dose is an important issue due to the hazards of ionizing radiation. The objective of this study was to measure the peak skin dose (PSD) and effective dose to estimate the deterministic and stochastic effects of a therapeutic interventional neuroradiologic procedure.Materials and MethodsThe cumulative dose (CD) and dose area product (DAP) were automatically recorded by a fluoroscopic machine and collected prospectively between April and November 2015. The study included 54 patients who underwent therapeutic neurointerventional radiology procedures. The CD of each patient was used to estimate the peak skin dose and the DAP was also calculated to estimate the effective dose.ResultsThe average estimated peak skin dose was 1,009.68 mGy. Two patients received radiation doses of more than 2 Gy, which is the threshold that may cause skin complications and radiation-induced cataract. The average effective dose was 35.32 mSv. The majority of patients in this study (85.2%) who underwent therapeutic neurointerventional radiologic procedures received effective doses greater than 20 mSv.ConclusionNot all therapeutic neurointerventional radiology procedures are safe from deterministic complications. A small number of patients received doses above the threshold for skin complications and radiation induced cataract. In terms of stochastic complications, most neurointerventional radiology procedures in this study were quite safe in terms of radiation-induced cancer.

Pediatric neurosurgery malpractice claims in Germany.

There is limited data regarding malpractice claims in pediatric neurosurgery. Aim of this study was to analyze the rate, subject, and outcome of malpractice claims faced by pediatric neurosurgeons. We analyzed malpractice claims in pediatric neurosurgical patients assigned to the review board of North Rhine Medical Council from 2012 to 2016. Claims were categorized as "medical error" or "adverse event, no medical error." Severity was graded from negligible (grade 1) to death (grade 6). Of 391 pediatric malpractice claims, seven (1.8%) concerned pediatric neurosurgery. Claims were related to cranial surgery (N = 5), spinal surgery (N = 1), and a neuro-interventional procedure (N = 1). Of operative cases, three were shunt operations, two were cranioplasty procedures, and one was a spinal fusion. Complications of medical care (adverse events) had occurred in all cases. A medical error was detected in only one case. Severity of damage was grade 2 (transient minor) in three, grade 3 (transient major) in one, and grade 5 (permanent major) in three cases, respectively. Pediatric neurosurgery accounted for 1.8% of all pediatric malpractice claims. In 14% of these claims, a medical error was confirmed. Malpractice claim rate thus appears to be lower than expected for a high-risk specialty. , adverse events were confirmed in all cases, a negligent medical error was rare. Adverse event rate appears to be a predictor for malpractice claim burden, highlighting the importance of surgical checklists, standard operating procedures and morbidity and mortality surveillance.