Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
1.
Neurosurgery ; 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32392300

RESUMO

BACKGROUND: Three-dimensional (3D) printing has revolutionized training, education, and device testing. Understanding the design and physical properties of 3D-printed models is important. OBJECTIVE: To systematically review the design, physical properties, accuracy, and experimental outcomes of 3D-printed vascular models used in neurointervention. METHODS: We conducted a systematic review of the literature between January 1, 2000 and September 30, 2018. Public/Publisher MEDLINE (PubMed), Web of Science, Compendex, Cochrane, and Inspec databases were searched using Medical Subject Heading terms for design and physical attributes of 3D-printed models for neurointervention. Information on design and physical properties like compliance, lubricity, flow system, accuracy, and outcome measures were collected. RESULTS: A total of 23 articles were included. Nine studies described 3D-printed models for stroke intervention. Tango Plus (Stratasys) was the most common material used to develop these models. Four studies described a population-representative geometry model. All other studies reported patient-specific vascular geometry. Eight studies reported complete reconstruction of the circle of Willis, anterior, and posterior circulation. Four studies reported a model with extracranial vasculature. One prototype study reported compliance and lubricity. Reported circulation systems included manual flushing, programmable pistons, peristaltic, and pulsatile pumps. Outcomes included thrombolysis in cerebral infarction, post-thrombectomy flow restoration, surgical performance, and qualitative feedback. CONCLUSION: Variations exist in the material, design, and extent of reconstruction of vasculature of 3D-printed models. There is a need for objective characterization of 3D-printed vascular models. We propose the development of population representative 3D-printed models for skill improvement or device testing.

2.
J Stroke Cerebrovasc Dis ; : 104836, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32414581

RESUMO

INTRODUCTION: Effectiveness of mechanical thrombectomy for mild-deficit stroke due to large-vessel occlusion is controversial. We present a single-center consecutive case series on thrombectomy for large-vessel occlusion mild stroke. We evaluated various thrombectomy parameters to better understand disagreement in the literature. METHODS: Data from a retrospective cohort of large-vessel occlusion mild stroke patients (National Institutes of Health Stroke Scale <6) treated with mechanical thrombectomy over 6 years and 2 months were analyzed. Patients were divided into 2 groups: successful reperfusion (modified Thrombolysis in Cerebral Infarction 2b or 3) and failed reperfusion (modified Thrombolysis in Cerebral Infarction 0,1, or 2a). Ninety-day modified Rankin Scale in-hospital mortality, and symptomatic hemorrhage rates were compared between groups. Multivariate logistic regression was performed to evaluate reperfusion status as a predictor of 90-day favorable (modified Rankin Scale 0-2) and excellent (modified Rankin Scale 0-1) outcomes. RESULTS: We identified 61 patients with large-vessel occlusion mild stroke who underwent thrombectomy. Reperfusion was successful in 49 patients and a failure in 12. The successful group exhibited significantly higher rates of favorable outcome (83.7% vs. 25.0%; p < 0.001) and excellent outcome (69.4% vs.16.7%; p = 0.002) at 90 days. In-hospital mortality was significantly higher in the failure group (41.7% vs.10.2%; p = 0.019). Multivariate logistic regression identified successful reperfusion as a significant predictor (p = 0.001) of 90-day favorable outcome. CONCLUSION: Reperfusion success was significantly associated with improved functional outcomes in large-vessel occlusion mild stroke mechanical thrombectomy. Future studies should consider reperfusion rates when evaluating the effectiveness of thrombectomy against that of medical management in these patients.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32372085

RESUMO

BACKGROUND: Instantaneous wave-free ratios (iFRs) are functional measures of arterial stenosis that have become essential to interventional cardiology procedures. Their use for intracranial submaximal angioplasty (angioplasty with an undersized balloon) has not been studied extensively. OBJECTIVE: To describe the feasibility and technique of iFR measurement for stenosis assessment during intracranial angioplasty. METHODS: We present a series of consecutive patients treated between January 1, 2017 and June 30, 2018 with submaximal intracranial angioplasty in whom pre- and postprocedure iFR measurements were obtained with a Verrata-Volcano pressure wire (Philips, Amsterdam, The Netherlands). We collected patient data on age, sex, comorbid conditions, presenting complaints, modified Rankin scale (mRS) score at admission, neurological findings, procedure duration, fluoroscopy time, intraprocedural complications, length of hospital stay, and mRS score at last clinical follow-up (favorable outcome, 0-2). Angiographic stenosis severity and iFR values were recorded before and after angioplasty. RESULTS: A total of 12 patients underwent iFR-guided angioplasty during the study period. The median patient age was 69.5 yr (range 48-81 yr). All patients had symptomatic intracranial arterial stenosis (3-basilar, 2-vertebral, 6-middle cerebral, 1-internal carotid). Preangioplasty stenosis ranged from 55% to 90%. The median postangioplasty reduction in stenosis was 17% (range 9%-30%). Preangioplasty values ranged from 0.30 to 0.40 (n = 4). Postangioplasty values ranged from 0.6 to 0.9 (n = 5). iFR values improved considerably in all patients. No procedure-related complications occurred. The median follow-up was 8.9 mo (range 3-25 mo). Follow-up outcomes were favorable in 10 patients. CONCLUSION: iFR measurement before and after intracranial angioplasty is feasible. It may be used to assess the adequacy of intracranial angioplasty.

4.
J Neurointerv Surg ; 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317370

RESUMO

Several anatomical variations of the radial artery have been described in the literature. Common variations include radial artery loop, recurrent branch, and anastomotic channels connecting the radial and brachial arteries. These variations can pose significant technical challenges to safe radial artery catheterization. Because radial access for neurointervention is becoming popular, appreciation of these variations and mastery of techniques for safe radial artery catheterization are of paramount importance. In this operative video,(video 1) we present a case of a 75-year-old man who underwent middle meningeal artery embolization for treatment of chronic subdural hematoma using a transradial approach. The patient was found to have a radial artery loop and a recurrent branch off the radial artery. The loop could not be negotiated with the conventional technique. We therefore used a microcatheter system with a stiff microwire to navigate and straighten the radial loop under road map guidance. The remaining procedure was performed successfully.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32215742

RESUMO

BACKGROUND: There is wide variation in the reported size of ruptured intracranial aneurysms and methods of size estimation. There is widespread belief that small aneurysms < 7 mm do not rupture. Therefore, we performed a systematic review and meta-analysis of the literature to determine the size of ruptured aneurysms according to aneurysm locations and methods of size estimation. METHODS: We searched PubMed, Cochrane, CINAHL, and EMBASE databases using a combination of Medical Subject Headings (MeSH) terms. We included articles that reported mean aneurysm size in consecutive series of ruptured intracranial. We excluded studies limited to a specific aneurysm location or type. The random-effects model was used to calculate overall mean size and location-specific mean size. We performed meta-regression to explain observed heterogeneity and variation in reported size. RESULTS: The systematic review included 36 studies and 12,609 ruptured intracranial aneurysms. Overall mean aneurysm size was 7.0 mm (95% confidence interval [CI 6.2-7.4]). Pooled mean size varied with location. Overall mean size of 2145 ruptured anterior circulation aneurysms was 6.0 mm (95% CI 5.6-6.4, residual I2 = 86%). Overall mean size of 743 ruptured posterior circulation aneurysms was 6.2 mm (95% CI 5.3-7.0, residual I2 = 93%). Meta-regression identified aneurysm location and definition of size (i.e., maximum dimension vs. aneurysm height) as significant determinants of aneurysm size reported in the studies. CONCLUSIONS: The mean size of ruptured aneurysms in most studies was approximately 7 mm. The general wisdom that aneurysms of this size do not rupture is incorrect. Location and size definition were significant determinants of aneurysm size.

6.
J Neurointerv Surg ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046993

RESUMO

BACKGROUND: A new dual resolution imaging x-ray detector system (Canon Medical Systems Corporation, Tochigi, Japan) has a standard resolution 194 µm pixel conventional flat-panel detector (FPD) mode and a high-resolution 76 µm high-definition (Hi-Def) mode in a single unit. The Hi-Def mode enhances the visualization of the intravascular devices. OBJECTIVE: We report the clinical experience and physician evaluation of this new detector system with Hi-Def mode for the treatment of intracranial aneurysms using a Pipeline embolization device (PED). METHODS: During intervention at our institute, under large field of view (FOV) regular resolution FPD mode imaging, the catheter systems and devices were first guided to the proximity of the treatment area. Final placement and deployment of the PED was performed under Hi-Def mode guidance. A post-procedure 9-question physician survey was conducted to qualitatively assess the impact of Hi-Def mode visualization on physicians' intraoperative decision-making. One-sample t-test was performed on the responses from the survey. Dose values reported by the x-ray unit were also recorded. RESULTS: Twenty-five cases were included in our study. The survey results indicated that, for each of the nine questions, the physicians in all cases indicated that the Hi-Def mode improved visualization compared with the FPD mode. For the 25 cases, the mean cumulative entrance air kerma was 2.35 Gy, the mean dose area product (DAP) was 173.71 Gy.cm2, and the mean x-ray exposure time was 39.30 min. CONCLUSIONS: The Hi-Def mode improves visualization of flow diverters and may help in achieving more accurate placement and deployment of devices.

8.
World Neurosurg ; 137: e454-e461, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32058116

RESUMO

OBJECTIVE: Despite an increasing focus on endovascular treatment of cerebral aneurysms, microsurgical clipping remains an integral part of management. We evaluated the safety and effectiveness of microsurgical clipping performed by dual-trained neurosurgeons at our institute, which has adopted an endovascular first approach. METHODS: We retrospectively reviewed clinical and radiographic data of 412 aneurysms in 375 patients treated with microsurgical clipping. Univariate and multivariate analyses were performed to identify predictive outcome factors. We defined favorable outcome as a modified Rankin Scale (mRS) score of 0-2 at last clinical follow-up; unfavorable outcome was an mRS score of 3-6. We compared outcomes in our series with those of seminal aneurysm clipping series. RESULTS: Clipping of 330 of 351 unruptured aneurysms (94.01%) was associated with favorable outcome during the follow-up period (mean, 26.5 months). On univariate analysis, older patient age, intraoperative rupture, and higher baseline mRS scores were associated with unfavorable outcome in the unruptured cohort. On multivariate analysis, older age, higher baseline mRS scores, and posterior circulation aneurysm location were predictive of unfavorable outcome. Clipping of 46 of 61 ruptured aneurysms (75.4%) was associated with favorable outcome during the follow-up period (mean, 23.1 months). On univariate analysis, left-sided aneurysms, intraoperative rupture, and large aneurysm size were associated with unfavorable outcome in the ruptured cohort. On multivariate analysis, female sex was predictive of unfavorable outcome. CONCLUSIONS: Our ruptured and unruptured cohort results compared favorably with those in seminal series. Treatment by neurosurgeons adept at both endovascular and microsurgical techniques may improve clinical outcomes.

9.
J Neurosurg ; : 1-6, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31978888

RESUMO

OBJECTIVE: The mortality rates for stroke are decreasing, yet it remains a leading cause of disability and the principal neurological diagnosis in patients discharged to nursing homes. The societal and economic burdens of stroke are substantial, with the total annual health care costs of stroke expected to reach $240.7 billion by 2030. Mechanical thrombectomy has been shown to improve functional outcomes compared to medical therapy alone. Despite an incremental cost of $10,840 compared to medical therapy, the improvement in functional outcomes and decreased disability have contributed to the cost-effectiveness of the procedure. In this study the authors describe a physician-led device bundle purchase program implemented for the delivery of stroke care. METHODS: The authors retrospectively reviewed the clinical and radiographic data and device-associated charges of 45 consecutive patients in whom a virtual "stroke bundle" model was used to purchase mechanical thrombectomy devices. RESULTS: Use of the stroke bundle to purchase mechanical thrombectomy devices resulted in an average savings per case of $2900.93. Compared to the traditional model of charging for devices à la carte, this represented an average savings of 25.2% per case. The total amount of savings for these initial 45 cases was $130,542.00. Thrombolysis in Cerebral Infarction scale grade 2b or 3 recanalization occurred in 38 patients (84.4%) using these devices. CONCLUSIONS: Purchasing devices through a bundled model resulted in substantial cost savings while maintaining the therapeutic efficacy of the procedure, further pushing the already beneficial long-term cost-benefit curve in favor of thrombectomy.

10.
Neurosurgery ; 86(2): 266-271, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30860254

RESUMO

BACKGROUND: The Pipeline Embolization Device (PED; Medtronic, Dublin, Ireland) has become an important tool for the treatment of cerebral aneurysms. Since FDA approval, there are ongoing efforts to increase aneurysm occlusion rates and reduce the incidence of complications. OBJECTIVE: To assess aneurysm occlusion and complication rates over time. METHODS: Retrospective analysis of consecutive anterior circulation aneurysms treated with a single PED between 2011 and 2016 at 3 academic institutions in the US was performed. Factors contributing to changes in aneurysm occlusion and complication rates over time were identified and evaluated. RESULTS: A total of 284 procedures were performed on 321 anterior circulation aneurysms in 284 patients. At a median follow-up of 13 mo (mean 18 mo), complete or near complete occlusion (>90%) was achieved in 85.9% of aneurysms. There was no significant change in aneurysm occlusion rate or procedure length over time. Thromboembolic complication occurred in 8.1% of procedures, and there was a trend toward decreased incidence from 16.3% in 2011/2012 to 3.3% in 2016 (P = .14). Hemorrhagic complications significantly decreased from 8.2% in 2011/2012 to 0 to 1.0% in 2014-2016 (P = .1). CONCLUSION: We report a notable drop in the rate of hemorrhagic and to a lesser extent thromboembolic complications with increased experience with PED in a multicenter cohort. Multiple factors are believed to contribute to this drop, including the evolved interpretation of platelet function testing, the switching of clopidogrel nonresponders to ticagrelor, and the reduced use of adjunctive coiling.

11.
J Neurointerv Surg ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822594

RESUMO

BACKGROUND: Angiographic parametric imaging (API), based on digital subtraction angiography (DSA), is a quantitative imaging tool that may be used to extract contrast flow parameters related to hemodynamic conditions in abnormal pathologies such as intracranial aneurysms (IAs). OBJECTIVE: To investigate the feasibility of using deep neural networks (DNNs) and API to predict IA occlusion using pre- and post-intervention DSAs. METHODS: We analyzed DSA images of IAs pre- and post-treatment to extract API parameters in the IA dome and the corresponding main artery (un-normalized data). We implemented a two-step correction to account for injection variability (normalized data) and projection foreshortening (relative data). A DNN was trained to predict a binary IA occlusion outcome: occluded/unoccluded. Network performance was assessed with area under the receiver operating characteristic curve (AUROC) and classification accuracy. To evaluate the effect of the proposed corrections, prediction accuracy analysis was performed after each normalization step. RESULTS: The study included 190 IAs. The mean and median duration between treatment and follow-up was 9.8 and 8.0 months, respectively. For the un-normalized, normalized, and relative subgroups, the DNN average prediction accuracies for IA occlusion were 62.5% (95% CI 60.5% to 64.4%), 70.8% (95% CI 68.2% to 73.4%), and 77.9% (95% CI 76.2% to 79.6%). The average AUROCs for the same subgroups were 0.48 (0.44-0.52), 0.67 (0.61-0.73), and 0.77 (0.74-0.80). CONCLUSIONS: The study demonstrated the feasibility of using API and DNNs to predict IA occlusion using only pre- and post-intervention angiographic information.

12.
J Neurointerv Surg ; 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848217

RESUMO

BACKGROUND: Recurrence of intracranial aneurysms after endovascular coiling is a serious clinical concern. OBJECTIVE: We hypothesized that recurrence is associated with aneurysm morphology and flow, as well as the coil intervention and the induced flow modifications. METHODS: We collected 52 primary-coiling aneurysm cases that were either occluded (n=34) or recurrent (n=18) at >1 year follow-up. We created aneurysm models from pre-coiling digital subtraction angiographic images, calculated aneurysm morphology, simulated pre-coiling hemodynamics, modeled coil deployment, and obtained post-coiling hemodynamics for each case. We performed univariable analysis on 26 morphologic, treatment-specific, and hemodynamic parameters to distinguish between recurrent and occluded groups, and multivariable analysis to identify independently significant parameters associated with recurrence. Univariable analysis was also performed on ruptured and unruptured aneurysm subcohorts separately to investigate if they shared specific significant parameters. RESULTS: Recurrence was associated with pre-coiling aneurysm morphologic and flow parameters including larger size (maximum dimension and volume), larger neck (diameter, area, and neck-to-parent-artery ratio), and higher flow momentum and kinetic energy. Recurrence was also associated with lower coil packing (packing density and uncoiled volume), higher post-treatment flow (velocity, momentum, and kinetic energy), lower post-treatment washout time, and higher post-treatment impingement force at the neck. Multivariable analysis identified two aneurysmal characteristics (neck diameter and pre-coiling flow kinetic energy), one coil packing parameter (uncoiled volume), and one post-treatment hemodynamic parameter (flow momentum) that were independently associated with recurrence. In ruptured aneurysms, recurrence was associated with larger neck (diameter and area), whereas in unruptured aneurysms, recurrence was associated with larger size (maximum dimension and volume). In both subcohorts, recurrence was associated with higher post-coiling flow momentum and kinetic energy. CONCLUSION: Recurrence at >1 year after coil treatment is associated with intrinsic aneurysm characteristics, coiling itself, and flow changes induced by coiling. Larger aneurysm size and neck, less coil packing, and higher intra-aneurysmal flow before and after coiling predict recurrence.

13.
PLoS One ; 14(12): e0226421, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31881029

RESUMO

BACKGROUND: Computer modeling of endovascular coiling intervention for intracranial aneurysm could enable a priori patient-specific treatment evaluation. To that end, we previously developed a finite element method (FEM) coiling technique, which incorporated simplified assumptions. To improve accuracy in capturing real-life coiling, we aimed to enhance the modeling strategies and experimentally test whether improvements lead to more accurate coiling simulations. METHODS: We previously modeled coils using a pre-shape based on mathematical curves and mechanical properties based on those of platinum wires. In the improved version, to better represent the physical properties of coils, we model coil pre-shapes based on how they are manufactured, and their mechanical properties based on their spring-like geometric structures. To enhance the deployment mechanics, we include coil advancement to the aneurysm in FEM simulations. To test if these new strategies produce more accurate coil deployments, we fabricated silicone phantoms of 2 patient-specific aneurysms in duplicate, deployed coils in each, and quantified coil distributions from intra-aneurysmal cross-sections using coil density (CD) and lacunarity (L). These deployments were simulated 9 times each using the original and improved techniques, and CD and L were calculated for cross-sections matching those in the experiments. To compare the 2 simulation techniques, Euclidean distances (dMin, dMax, and dAvg) between experimental and simulation points in standardized CD-L space were evaluated. Univariate tests were performed to determine if these distances were significantly different between the 2 simulations. RESULTS: Coil deployments using the improved technique agreed better with experiments than the original technique. All dMin, dMax, and dAvg values were smaller for the improved technique, and the average values across all simulations for the improved technique were significantly smaller than those from the original technique (dMin: p = 0.014, dMax: p = 0.013, dAvg: p = 0.045). CONCLUSION: Incorporating coil-specific physical properties and mechanics improves accuracy of FEM simulations of endovascular intracranial aneurysm coiling.


Assuntos
Procedimentos Endovasculares/instrumentação , Aneurisma Intracraniano/cirurgia , Prótese Vascular , Análise de Elementos Finitos , Humanos , Modelos Biológicos
14.
Interv Neuroradiol ; : 1591019919888130, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31766960

RESUMO

BACKGROUND: Controversy exists regarding the optimum number of flow diverters for the treatment of intracranial aneurysms. We explored the effect of the number of Pipeline embolization devices (PEDs; Medtronic, Dublin, Ireland) deployed on rates of aneurysm occlusion and complications. METHODS: Consecutive patients who underwent saccular intracranial aneurysm treatment solely with the PED were included in this retrospective study. Computed tomographic, magnetic resonance, or digital subtraction angiographic images at 6 and 12 months and last follow-up (>12 months) were reviewed for aneurysm occlusion. Complication and retreatment rates were recorded and analyzed statistically. RESULTS: The study included 141 aneurysm treatments in 119 patients. A single PED was deployed in 105 cases, two PEDs in 31 cases, and three PEDs in 5 cases (total = 182 devices). Six-month angiographic data were available for 103 patients. Occlusion rates were 67.1% for single-PED cases and 90.0% for cases with > 1 PED (p = 0.028). The 12-month occlusion rate (follow-up available for 132) for single-PED cases was 74.7% compared to 91.7% for multiple-PED cases (p = 0.04). On multivariate analysis, number of PEDs was an independent predictor of aneurysm occlusion at 12 months (odds ratio 6.3, 95% confidence interval 1.8-22.8, p = 0.005). Thromboembolic complication rates were the same in the single- and multiple-PED treatment groups (2.8%). The retreatment rate was higher in patients treated with a single PED (16.2% vs. 0%, p = 0.01). CONCLUSIONS: Deployment of > 1 Pipeline embolization device was associated with higher intracranial aneurysm occlusion and lower retreatment rates. No significant difference was found in complication rates.

15.
J Neurointerv Surg ; 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444288

RESUMO

BACKGROUND: Angiographic parametric imaging (API) is an imaging method that uses digital subtraction angiography (DSA) to characterize contrast media dynamics throughout the vasculature. This requires manual placement of a region of interest over a lesion (eg, an aneurysm sac) by an operator. OBJECTIVE: The purpose of our work was to determine if a convolutional neural network (CNN) was able to identify and segment the intracranial aneurysm (IA) sac in a DSA and extract API radiomic features with minimal errors compared with human user results. METHODS: Three hundred and fifty angiographic images of IAs were retrospectively collected. The IAs and surrounding vasculature were manually contoured and the masks put to a CNN tasked with semantic segmentation. The CNN segmentations were assessed for accuracy using the Dice similarity coefficient (DSC) and Jaccard index (JI). Area under the receiver operating characteristic curve (AUROC) was computed. API features based on the CNN segmentation were compared with the human user results. RESULTS: The mean JI was 0.823 (95% CI 0.783 to 0.863) for the IA and 0.737 (95% CI 0.682 to 0.792) for the vasculature. The mean DSC was 0.903 (95% CI 0.867 to 0.937) for the IA and 0.849 (95% CI 0.811 to 0.887) for the vasculature. The mean AUROC was 0.791 (95% CI 0.740 to 0.817) for the IA and 0.715 (95% CI 0.678 to 0.733) for the vasculature. All five API features measured inside the predicted masks were within 18% of those measured inside manually contoured masks. CONCLUSIONS: CNN segmentation of IAs and surrounding vasculature from DSA images is non-inferior to manual contours of aneurysms and can be used in parametric imaging procedures.

16.
J Neuroimaging ; 29(5): 565-572, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31339613

RESUMO

BACKGROUND AND PURPOSE: Visualization of structural details of treatment devices during neurointerventional procedures can be challenging. A new true two-resolution imaging X-ray detector system features a 194 µm pixel conventional flat-panel detector (FPD) mode and a 76 µm pixel high-resolution high-definition (Hi-Def) zoom mode in one detector panel. The Hi-Def zoom mode was developed for use in interventional procedures requiring superior image quality over a small field of view (FOV). We report successful use of this imaging system during intracranial aneurysm treatment in 1 patient with a Pipeline-embolization device and 1 patient with a low-profile visualized intramural support (LVIS Blue) device plus adjunctive coiling. METHODS: A guide catheter was advanced from the femoral artery insertion site to the proximity of each lesion using standard FPD mode. Under magnified small FOV Hi-Def imaging mode, an intermediate catheter and microcatheters were guided to the treatment site, and the PED and LVIS Blue plus coils were deployed. Radiation doses were tracked intraprocedurally. RESULTS: Critical details, including structural changes in the PED and LVIS Blue and position and movement of the microcatheter tip within the coil mass, were more readily apparent in Hi-Def mode. Skin-dose mapping indicated that Hi-Def mode limited radiation exposure to the smaller FOV of the treatment area. CONCLUSIONS: Visualization of device structures was much improved in the high-resolution Hi-Def mode, leading to easier, more controlled deployment of stents and coils than conventional FPD mode.

17.
World Neurosurg ; 128: e513-e521, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31048049

RESUMO

BACKGROUND: Various studies have suggested that age ≥80 years is associated with a higher rate of complications after carotid artery stenting (CAS). The Buffalo Risk Assessment Scale (BRASS) predicts complications in symptomatic patients undergoing CAS. Application of the BRASS has shown the ability to improve patient selection. We used the BRASS system to evaluate whether the higher rate of complications associated with CAS in the elderly is related to vascular anatomy. METHODS: A retrospective review of CAS was performed at our institution over 7 years. Demographic information, anatomic characteristics, BRASS categorization, and outcome measures were compared between elderly (≥80 years) and younger patients (<80 years). RESULTS: The study included 447 patients: 335 patients (75%) <80 years and 112 patients (25%) ≥80 years. There were significantly more elderly patients in the high-risk BRASS category (P < 0.01), and more young patients in the low-risk BRASS category (P = 0.04). The complication rates in the 2 groups were similar. Older patients were more likely to harbor complex vascular anatomy: they had significantly higher rates of types II and III aortic arches (P = 0.01 and P < 0.01, respectively), higher percentage of tortuous carotid vessels (P < 0.01), and higher rates of hostile anatomy for deployment of distal embolic protection devices (P = 0.02). CONCLUSIONS: Complex vascular anatomy, rather than age, is the key factor behind the higher CAS-associated complication rate in the elderly. Complications can be avoided through proper patient selection and stratifying patients based on anatomic characteristics, which can be achieved through the BRASS scoring system.


Assuntos
Aorta Torácica/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Stents , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Aorta Torácica/anatomia & histologia , Artérias Carótidas/anatomia & histologia , Artérias Carótidas/cirurgia , Doenças das Artérias Carótidas/cirurgia , Procedimentos Endovasculares , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Calcificação Vascular/epidemiologia
19.
World Neurosurg ; 126: 228-236, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30878752

RESUMO

INTRODUCTION: Embolization of the middle meningeal artery (MMA) has emerged as a minimally invasive means of managing subdural hematoma. The purpose of this study was to systematically review the literature on the safety and effectiveness of this treatment and to share our clinical experience. METHODS: This review was registered with PROSPERO. PubMed, CINAHL, EMBASE, and the Cochrane Library were searched using MeSH (Medical Subject Headings) terms for MMA embolization and chronic subdural hematoma (CSDH) from January 2000 to November 2018. All articles in the English language literature describing MMA embolization for CSDH were included, irrespective of study design. Consecutive patients who underwent MMA embolization at our hospital between January 2017 and June 2018 comprised our clinical experience. RESULTS: Fifteen studies with 193 procedures were included in the review. Ninety-five cases (49.2%) involved primary MMA embolization; 88 embolizations (45.6%) for recurrent CSDH and 10 (5.2%) for prophylaxis after surgical evacuation were performed. Recurrence after MMA embolization requiring further treatment occurred in 7 cases (3.6%). All other patients had symptomatic relief with no further recurrence. No procedure-related complications were reported. Polyvinyl alcohol was the most commonly used material. Our series included 8 patients treated with Onyx. All had symptom relief and significant reduction in hematoma size; no recurrences or procedure-related complications were observed. CONCLUSIONS: MMA embolization of CSDH is safe and effective for CSDH treatment based on a documented recurrence rate of 3.6% and lack of reported complications.


Assuntos
Embolização Terapêutica/métodos , Hematoma Subdural Crônico/terapia , Embolização Terapêutica/efeitos adversos , Humanos , Resultado do Tratamento
20.
Neurosurgery ; 85(3): 384-393, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30113665

RESUMO

BACKGROUND: Current outcomes prediction tools are largely based on and limited by regression methods. Utilization of machine learning (ML) methods that can handle multiple diverse inputs could strengthen predictive abilities and improve patient outcomes. Inpatient length of stay (LOS) is one such outcome that serves as a surrogate for patient disease severity and resource utilization. OBJECTIVE: To develop a novel method to systematically rank, select, and combine ML algorithms to build a model that predicts LOS following craniotomy for brain tumor. METHODS: A training dataset of 41 222 patients who underwent craniotomy for brain tumor was created from the National Inpatient Sample. Twenty-nine ML algorithms were trained on 26 preoperative variables to predict LOS. Trained algorithms were ranked by calculating the root mean square logarithmic error (RMSLE) and top performing algorithms combined to form an ensemble. The ensemble was externally validated using a dataset of 4592 patients from the National Surgical Quality Improvement Program. Additional analyses identified variables that most strongly influence the ensemble model predictions. RESULTS: The ensemble model predicted LOS with RMSLE of .555 (95% confidence interval, .553-.557) on internal validation and .631 on external validation. Nonelective surgery, preoperative pneumonia, sodium abnormality, or weight loss, and non-White race were the strongest predictors of increased LOS. CONCLUSION: An ML ensemble model predicts LOS with good performance on internal and external validation, and yields clinical insights that may potentially improve patient outcomes. This systematic ML method can be applied to a broad range of clinical problems to improve patient care.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA