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1.
Polymers (Basel) ; 14(22)2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36433175

RESUMEN

The increase in the use of additive manufacturing (AM) has led to the need for filaments with specific and functional properties in face of requirements of structural parts production. The use of eco-friendly reinforcements (i.e., natural fibers) as an alternative to those more traditional synthetic counterparts is still scarce and requires further investigation. The main objective of this work was to develop short curauá fiber-reinforced polylactic acid (PLA) composites made via fused deposition modeling. Three different fiber lengths (3, 6, and 8 mm), and three concentrations in terms of weight percentage (2, 3.5, and 5 wt.%) were used to fabricate reinforced PLA filaments. Tensile and flexural tests in accordance with their respective American Society for Testing and Materials (ASTM) standards were performed. A thermal analysis was also carried out in order to investigate the thermal stability of the new materials. It was found that the main driving factor for the variation in mechanical properties was the fiber weight fraction. The increase in fiber length did not provide any significant benefit on the mechanical properties of the curauá fiber-reinforced PLA composite printed parts. The composites produced with PLA filaments reinforced by 3 mm 2% curauá fiber presented the overall best mechanical and thermal properties of all studied groups. The curauá fiber-reinforced PLA composites made via fused deposition modeling may be a promising innovation to improve the performance of these materials, which might enable them to serve for new applications.

2.
Neurosurgery ; 90(3): 287-292, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34995246

RESUMEN

BACKGROUND: Transradial access (TRA) for neuroendovascular procedures is increasing in prevalence. The safety benefits of TRA at a patient level may be offset at a population level by a paradoxical increase in transfemoral access (TFA) vascular access site complications (VASCs), the so-called "radial paradox." OBJECTIVE: To study the effect of TRA adoption on TFA performance and outcomes in neuroendovascular procedures. METHODS: Data were collected for all procedures performed over a 10-mo period after radial adoption at a single center. RESULTS: Over the study period, 1084 procedures were performed, including 719 (66.3%) with an intent to treat by TRA and 365 (33.7%) with an intent to treat by TFA. Thirty-two cases (4.4%) crossed over from TRA to TFA, and 2 cases (0.5%) crossed over from TFA to TRA. TFA was performed in older patients (mean [standard deviation] TFA, 63 [15] vs TRA, 56 [16] years) using larger sheath sizes (≥7 French; TFA, 56.2% vs TRA, 2.3%) ( P < .001 for both comparisons). Overall, 29 VASCs occurred (2.7%), including 27 minor (TFA, 4.6% [18/395] vs TRA, 1.3% [9/689], P = .002) and 2 major (TFA, 0.3% [1/395] vs TRA, 0.1% [1/689], P > .99) complications. Independent predictors of VASC included TFA (OR 2.8, 95% confidence interval [CI] 1.1-7.4) and use of dual antiplatelet therapy (OR 4.2, 95% CI 1.6-11.1). CONCLUSION: TFA remains an important access route, despite a predominantly radial paradigm, and is disproportionately used in patients at increased risk for VASCs. TFA proficiency may still be achieved in predominantly radial practices without an increase in femoral complications.


Asunto(s)
Cateterismo Periférico , Arteria Radial , Anciano , Cateterismo Periférico/efectos adversos , Cateterismo Periférico/métodos , Estudios Cruzados , Arteria Femoral/cirugía , Humanos , Extremidad Inferior , Arteria Radial/cirugía , Resultado del Tratamiento
3.
J Neurointerv Surg ; 14(4): 397-402, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34083399

RESUMEN

BACKGROUND: Transradial arterial access (TRA) for cerebral diagnostic angiography is associated with fewer access site complications than transfemoral access (TFA). However, concerns about increased procedure time and radiation exposure with TRA may slow its adoption. Our objective was to measure TRA rates of success and fluoroscopy time per vessel after 'radial-first' adoption and to compare these rates to those obtained with TFA. METHODS: We examined 500 consecutive cerebral angiograms on an intent-to-treat basis during the first full year of radial-first adoption, recording patient and procedural characteristics and outcomes. RESULTS: Over a 9-month period at a single center, 457 of 500 angiograms (91.4%) were performed with intent-to-treat via TRA, and 431 cases (86.2%) were ultimately performed via TRA. One patient (0.2%) experienced a temporary neurologic deficit in the TRA group, and none (0%) did in the TFA group (p=0.80). The mean±SD fluoroscopy time per vessel decreased significantly from the first half of the study to the second half for TRA (5.0±3.8 vs 3.4±3.5 min/vessel; p<0.001), while TFA time remained unchanged (3.7±1.8 vs 3.5±1.4 min/vessel; p=0.69). The median fluoroscopy time per vessel for TRA became faster than that for TFA after 150 angiograms. CONCLUSION: Of 500 consecutive angiograms performed during the first full year of radial-first implementation, 86.2% were performed successfully using TRA. TRA efficiency exceeded that of TFA after 150 angiograms. Concerns about the length of procedure or radiation exposure should not be barriers to TRA adoption.


Asunto(s)
Arteria Femoral , Exposición a la Radiación , Angiografía Cerebral/métodos , Arteria Femoral/diagnóstico por imagen , Fluoroscopía/efectos adversos , Humanos , Arteria Radial/diagnóstico por imagen , Resultado del Tratamiento
4.
Phys Rev Lett ; 126(19): 190502, 2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-34047616

RESUMEN

We study the detection of continuous-variable entanglement, for which most of the existing methods designed so far require a full specification of the devices, and we present protocols for entanglement detection in a scenario where the measurement devices are completely uncharacterized. We first generalize, to the continuous variable regime, the seminal results by Buscemi [Phys. Rev. Lett. 108, 200401 (2012)PRLTAO0031-900710.1103/PhysRevLett.108.200401] and Branciard et al. [Phys. Rev. Lett. 110, 060405 (2013)PRLTAO0031-900710.1103/PhysRevLett.110.060405], showing that all entangled states can be detected in this scenario. Most importantly, we then describe a practical protocol that allows for the measurement-device-independent certification of entanglement of all two-mode entangled Gaussian states. This protocol is feasible with current technology as it makes use only of standard optical setups such as coherent states and homodyne measurements.

5.
J Neurointerv Surg ; 13(12): 1190, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33685982

RESUMEN

Cavernous sinus dural arteriovenous fistulas (CS-DAVF) can have an indolent course, with insidious onset, but still showing a high likelihood of spontaneous resolution.1 Nevertheless, symptoms in a subset of patients evolve more rapidly, with malignant signs on imaging, warranting intervention.2 We report on a patient in his 40s presenting with redness and proptosis of the right eye, intermittent blurred vision and diplopia. Once ophthalmological examination revealed increased intraocular pressure and imaging showed cortical venous congestion, the decision was made to obliterate a CS-DAVF involving the posteromedial right cavernous sinus.Multiple arteries including branches of the ascending pharyngeal artery, occipital artery and bilateral meningohypophyseal trunks supplied the fistula. Once transarterial embolization was deemed unsafe and both inferior petrosal sinuses did not grant access to the right cavernous sinus, a direct puncture to the cavernous sinus was performed to successfully coil the involved compartments.3-5 The aid of DynaCT imaging and needle guidance software is emphasized (video 1). neurintsurg;13/12/1190/V1F1V1Video 1.


Asunto(s)
Seno Cavernoso , Malformaciones Vasculares del Sistema Nervioso Central , Embolización Terapéutica , Seno Cavernoso/diagnóstico por imagen , Seno Cavernoso/cirugía , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Senos Craneales , Humanos , Punciones
6.
Neurosurgery ; 88(6): E505-E509, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33582816

RESUMEN

BACKGROUND: Transradial artery (TRA) catheterization for neuroendovascular procedures is associated with a lower risk of complications than transfemoral artery (TFA) procedures. However, the majority of literature on TRA access pertains to diagnostic procedures rather than interventional treatments. OBJECTIVE: To compare TRA and TFA approaches for cerebrovascular interventions. METHODS: All patients with an endovascular intervention performed at a single center from October 1, 2018 to December 31, 2019 were retrospectively analyzed. Patients were grouped into 2 cohorts on the basis of whether TRA or TFA access was used. Outcomes included complications, fluoroscopy times, and total contrast administered. RESULTS: A total 579 interventional treatments were performed during the 15-mo study period. TFA procedures (n = 417) were associated with a significantly higher complication rate than TRA (n = 162) procedures (43 cases [10%] vs 5 cases [3%]; P = .008). After excluding patients who underwent thrombectomy and performing a propensity adjustment (including age, sex, pathology, procedure, sheath size, and catheter size), TRA catheterization was associated with decreased odds of a complication (odds ratio, 0.25; 95% CI 0.085-0.72; P = .01), but no significant difference in the amount of contrast administered (6.7-mL increase; 95% CI, -7.2 to 20.6; P = .34) or duration of fluoroscopy (2.1-min increase; 95% CI, -2.5 to 6.7; P = .37) compared with TFA catheterization. CONCLUSION: Neurointerventional procedures and treatments for a variety of pathologies can be performed successfully using the TRA approach, which is associated with a lower risk of complications and no difference in fluoroscopy duration compared with the TFA approach.


Asunto(s)
Cateterismo Periférico/métodos , Trastornos Cerebrovasculares/terapia , Procedimientos Endovasculares/métodos , Arteria Femoral/cirugía , Arteria Radial/cirugía , Anciano , Estudios de Casos y Controles , Femenino , Fluoroscopía/métodos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
7.
J Neurosurg ; 135(4): 1208-1213, 2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33636706

RESUMEN

OBJECTIVE: Middle meningeal artery (MMA) embolization is a promising treatment strategy for chronic subdural hematomas (cSDHs). However, studies comparing MMA embolization and conventional therapy (surgical intervention and conservative management) are limited. The authors aimed to compare MMA embolization versus conventional therapy for cSDHs using a propensity-adjusted analysis. METHODS: A retrospective study of all patients with cSDH who presented to a large tertiary center over a 2-year period was performed. MMA embolization was compared with surgical intervention and conservative management. Neurological outcome was assessed using the modified Rankin Scale (mRS). A propensity-adjusted analysis compared MMA embolization versus surgery and conservative management for all individual cSDHs. Primary outcomes included change in hematoma diameter, treatment failure, and complete resolution at last follow-up. RESULTS: A total of 231 patients with cSDH met the inclusion criteria. Of these, 35 (15%) were treated using MMA embolization, and 196 (85%) were treated with conventional treatment. On the latest follow-up, there were no statistically significant differences between groups in the percentage of patients with worsening mRS scores. Of the 323 total cSDHs found in 231 patients, 41 (13%) were treated with MMA embolization, 159 (49%) were treated conservatively, and 123 (38%) were treated with surgical evacuation. After propensity adjustment, both surgery (OR 12, 95% CI 1.5-90; p = 0.02) and conservative therapy (OR 13, 95% CI 1.7-99; p = 0.01) were predictors of treatment failure and incomplete resolution on follow-up imaging (OR 6.1, 95% CI 2.8-13; p < 0.001 and OR 5.4, 95% CI 2.5-12; p < 0.001, respectively) when compared with MMA embolization. Additionally, MMA embolization was associated with a significant decrease in cSDH diameter on follow-up relative to conservative management (mean -8.3 mm, 95% CI -10.4 to -6.3 mm, p < 0.001). CONCLUSIONS: This propensity-adjusted analysis suggests that MMA embolization for cSDH is associated with a greater extent of hematoma volume reduction with fewer treatment failures than conventional therapy.

8.
Oper Neurosurg (Hagerstown) ; 20(4): E284-E285, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33517417

RESUMEN

Initially developed for large and giant wide-necked aneurysms of the internal carotid artery, flow diverter devices are now used in almost every location safely and with effectiveness.1-5 This video demonstrates a unique case of a giant aneurysm of the right petrous internal carotid artery in a 20-yr-old patient. This is an extremely rare location, and most of patients are asymptomatic.3-6 Signs of compression of the seventh and eight cranial nerves can be present and even Horner syndrome and lower cranial nerves neuropathies. Nevertheless, rupture can lead to epistaxis and otorrhagia, and ultimately to hemorrhagic shock. The patient in the current report was otherwise healthy but presented with lightheadedness and dizziness for 10 d. The patient consented to the procedure. There was no history of major trauma or head and neck infection. A transradial endovascular flow diversion embolization of a giant aneurysm of the petrous internal carotid artery is herein demonstrated in a stepwise manner. A triaxial system was used to deploy 3 overlapping devices. Concepts of J-wire technique, multiple coverage,1 and the so-called weld technique are emphasized. The role of adjunctive coiling and main reasons for failure are also discussed.7,8 Brief cases of flow diversion embolization of aneurysms of different morphologies at different locations are used to highlight the importance of assessing vessel wall apposition and follow-up imaging.


Asunto(s)
Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/cirugía , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Resultado del Tratamiento
9.
J Neurointerv Surg ; 13(7): 614-618, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32958518

RESUMEN

BACKGROUND: Both stentriever and direct-aspiration thrombectomy effectively treat large-vessel occlusions. However, data are limited comparing clinical outcomes after aspiration-first versus stentriever-assisted aspiration for thrombectomy. METHODS: A retrospective cohort study compared procedure times and radiographic outcomes after two mechanical thrombectomy techniques (aspiration first or stentriever). To minimize bias and variability inherent to multi-operator series, we assessed consecutive patients with cerebrovascular occlusions treated by a single surgeon during a 1 year period at two stroke centers. Expanded Thrombolysis in Cerebral Infarction (eTICI) grades were assessed by an investigator blinded to treatment. RESULTS: Data from 93 patients (median age 70 years) were analyzed: 73 patients (78.5%) were treated with a strentriever-first strategy and 20 (21.5%) were treated with aspiration first, with stentriever rescue therapy required in only three of these cases following unsuccessful aspiration. There were no significant differences in patient demographics, sites of occlusion, or rates of tandem occlusions between aspiration-first and stentriever-assisted groups (p≥0.36). The rate of first-pass eTICI ≥2b was 75.0% (15/20) for aspiration-first and 52.1% (38/73) for strentriever-first groups (p=0.07), while the rate of final eTICI ≥2b was 100% (20/20) and 82.2% (60/72), respectively (p=0.04). The aspiration-first technique was associated with procedural times ≤25 min in a multivariable analysis (adjusted OR 4.77, 95% CI 1.15 to 18.39; p=0.03). CONCLUSIONS: In this single-surgeon series, an aspiration-first technique was associated with a statistically significant improvement in eTICI outcomes and faster procedure times compared with stentriever-assisted aspiration. Further prospective studies are necessary to minimize selection bias inherent in this study design.


Asunto(s)
Trastornos Cerebrovasculares/diagnóstico por imagen , Trastornos Cerebrovasculares/cirugía , Paracentesis/métodos , Stents , Trombectomía/métodos , Dispositivos de Acceso Vascular , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento
10.
J Neurointerv Surg ; 13(7): 657-660, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33077579

RESUMEN

BACKGROUND: Recently, middle meningeal artery (MMA) embolization has emerged as a potentially safe and effective method of treating chronic subdural hematoma (cSDH). OBJECTIVE: To report a single-center experience with MMA embolization and examines the type of embolic material used, the extent of penetration, and the number of MMA branches embolized. METHODS: A retrospective analysis of all patients with MMA embolization from 2018 through 2019 was performed. A failed outcome was defined as either surgical rescue and/or greater than 10 mm of hematoma residual or reaccumulation following embolization. RESULTS: Of 35 patients, surgery had failed for 9 (26%) and initial conservative treatment had failed for 6 (17%). Of 41 MMA embolizations, including those in six patients with bilateral cSDH who underwent bilateral MMA embolization, 29 (72%) were performed using ethylene vinyl alcohol copolymer (Onyx), 7 (17%) using particles, and 5 (12%) using n-butyl cyanoacrylate. Both the anterior and posterior MMA divisions were embolized in 29 cases (71%); distal penetration of these branches was achieved in 25 embolizations (61%). Twenty-six (63%) cSDHs completely resolved. Complete resolution was seen in 22 of 29 hematomas (76%) in which both anterior and posterior MMA branches were occluded versus 4 of 12 (33%) following single-branch embolization (p=0.014). Embolization of one cSDH (2%) failed. CONCLUSION: MMA embolization of cSDHs appears to be both safe and efficacious. Furthermore, embolization of both the anterior and posterior MMA branches may be associated with increased odds of complete resolution.


Asunto(s)
Embolización Terapéutica/métodos , Enbucrilato/administración & dosificación , Hematoma Subdural Crónico/diagnóstico por imagen , Hematoma Subdural Crónico/terapia , Arterias Meníngeas/diagnóstico por imagen , Polivinilos/administración & dosificación , Anciano , Anciano de 80 o más Años , Femenino , Hematoma Subdural Crónico/cirugía , Humanos , Masculino , Arterias Meníngeas/cirugía , Persona de Mediana Edad , Estudios Retrospectivos
11.
Oper Neurosurg (Hagerstown) ; 20(1): E37-E38, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33316814

RESUMEN

Sidewall aneurysm treatment often requires complex management strategies. These can include advanced clipping techniques or stent-assisted coiling techniques. Endovascular coiling alone has been associated with high recurrence rates and is often not feasible.1-4 Flow-diversion embolization has recently become a standard of care for many aneurysms, demonstrating high occlusion rates.4,5 However, the third generation of coil-assist stents can be delivered with 0.0165" microcatheters, being an ideal adjunct to manage this group of aneurysms in more distal locations. In this video, a 16-yr-old teenager with Parry-Romberg syndrome and congenital adrenal hyperplasia had an incidental finding of a 6.5-mm sidewall aneurysm arising off the angular branch of the left middle cerebral artery, found during the work-up of complex partial seizures. The patient consented to the procedure. Due to his young age and aneurysm size, a decision was made to treat the aneurysm through an endovascular approach. Under general anesthesia, a transfemoral approach was carried out using a 6-French short sheath. A 6-French guiding catheter was left in the distal cervical left internal carotid artery; a 0.0165" microcatheter was used to first deploy a 3.0 × 15 mm Neuroform Atlas stent, completely covering the length of the aneurysm. Then, the stent was traversed with the microcatheter to coil the aneurysm. Follow-up cerebral angiogram confirmed complete occlusion of the aneurysm.


Asunto(s)
Embolización Terapéutica , Aneurisma Intracraneal , Adolescente , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/cirugía , Stents , Resultado del Tratamiento
12.
Phys Rev Lett ; 124(21): 210501, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32530693

RESUMEN

Steady technological advances are paving the way for the implementation of the quantum internet, a network of locations interconnected by quantum channels. Here we propose a model to simulate a quantum internet based on optical fibers and employ network-theory techniques to characterize the statistical properties of the photonic networks it generates. Our model predicts a continuous phase transition between a disconnected and a highly connected phase and that the typical photonic networks do not present the small world property. We compute the critical exponents characterizing the phase transition, provide quantitative estimates for the minimum density of nodes needed to have a fully connected network and for the average distance between nodes. Our results thus provide quantitative benchmarks for the development of a quantum internet.

13.
Oper Neurosurg (Hagerstown) ; 19(5): E518-E519, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32442280

RESUMEN

The retrosigmoid approach is one of the main approaches used in the surgical management of pontine cavernous malformations. It definitely provides a lateral route to large central lesions but also makes possible resection of some ventral lesions as an alternative to the petrosal approaches. However, when these vascular malformations do not emerge on surface, one of the safe corridors delimited by the origin of the trigeminal nerve and the seventh-eight cranial nerve complex can be used.1-5 Baghai et al2 described the lateral pontine safe entry zone in 1982, as an alternative to approaches through the floor of the fourth ventricle when performing tumor biopsies. They advocated a small neurotomy performed right between the emergence of the trigeminal nerve and the facial-vestibulocochlear cranial nerves complex. Accurate image guidance, intraoperative cranial nerve monitoring, and comprehensive anatomical knowledge are critical for this approach.4,5 Knowing the natural history of a brainstem cavernous malformation after bleeding,6 we sought to demonstrate in this video: (1) the use of the retrosigmoid craniotomy in lateral decubitus for resection of deep-seated pontine cavernous malformations; (2) the wide opening of arachnoid membranes and dissection of the superior petrosal vein complex to improve surgical freedom and prevent use of fixed cerebellar retraction; and (3) the opening of the petrosal fissure and exposure of the lateral pontine zone for gross total resection of a cavernous malformation in a 19-yr-old female with a classical crossed brainstem syndrome. She had full neurological recovery after 3 mo of follow-up. The patient consented in full to the surgical procedure and publication of the video and manuscript.


Asunto(s)
Neoplasias del Tronco Encefálico , Puente , Neoplasias del Tronco Encefálico/diagnóstico por imagen , Neoplasias del Tronco Encefálico/cirugía , Craneotomía , Femenino , Humanos , Procedimientos Neuroquirúrgicos , Puente/diagnóstico por imagen , Puente/cirugía , Adulto Joven
14.
Polymers (Basel) ; 12(4)2020 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-32283753

RESUMEN

The main objective of this work was to investigate the effect of hybridization on the mechanical and thermal properties of intralaminar natural fiber-reinforced hybrid composites based on sisal. Ramie, sisal and curauá fibers were selected as natural fiber reinforcements for the epoxy matrix based composites, which were produced by the hand lay-up technique. Tensile, flexural and impact tests were carried out according to American society for testing and materials (ASTM) standards to characterize the hybrid composites, while differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to evaluate the thermal properties. It was found that the mechanical properties are improved by hybridization of sisal based composites. The thermal analysis showed that the hybridization did not significantly affect the thermal stability of the composites. A scanning electron microscopy (SEM) was used to examine the fracture surface of the tested specimens. The SEM images showed a brittle fracture of the matrix and fiber breakage near the matrix.

15.
World Neurosurg ; 139: e406-e411, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32304888

RESUMEN

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) is debilitating in elderly patients, but literature regarding this population is scarce, and clinical decision-making remains debated. Outcomes of elderly patients with aSAH stratified by age and clinical presentation were analyzed. METHODS: Patients treated for aSAH were retrospectively analyzed. Patients were trichotomized into a young cohort (aged <60 years [n = 268]) and 2 elderly cohorts (aged 60-65 years [n = 60] and ≥65 years [n = 77]). The elderly cohorts were analyzed by poor or good scores at presentation (Hunt and Hess [HH] score >3 vs. ≤3, respectively) and poor functional outcome (modified Rankin Scale score >2). RESULTS: Of 137 elderly patients, 121 had a 6-year follow-up. The >65-year-olds (75% [52/69]) were more likely to have poor functional outcomes than the 60 to 65-year-olds (48% [25/52]) (odds ratio, 3.3; 95% confidence interval, 1.5-7.1; P = 0.002). Among those with an HH score ≤3 at presentation (n = 90), the >65-year-old cohort had poorer outcomes than the 60 to 65-year-old cohort at 6-year follow-up (69% [35/51] vs. 36% [14/39], respectively; odds ratio, 3.9; 95% confidence interval, 1.6-9.4; P = 0.003). Among patients with an HH score >3, no statistically significant differences in functional outcome were observed between the >65-year-old (n = 18) and 60 to 65-year-old (n = 13) cohorts. CONCLUSIONS: Elderly patients with aSAH are at high risk for poor functional outcomes. However, among those presenting with good HH scores, younger-elderly patients (aged 60-65 years) tend to fare better than older-elderly patients (aged >65 years). Elderly patients presenting with high-grade aSAH fare poorly regardless of age, which can inform clinical decision-making and prognostication.


Asunto(s)
Aneurisma Roto/terapia , Hemorragia Subaracnoidea/terapia , Adulto , Anciano , Embolización Terapéutica , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
17.
World Neurosurg ; 135: e679-e685, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31884126

RESUMEN

BACKGROUND: Preoperative embolization of meningiomas to reduce tumor vascularity and intraoperative blood loss remains controversial. Incomplete devascularization on angiography is not significantly correlated with intraoperative estimated blood loss (EBL). Magnetic resonance imaging (MRI) may provide a better assessment of devascularization and prediction of EBL. METHODS: We retrospectively analyzed patients undergoing preoperative embolization for intracranial meningiomas. Cohorts based on postembolization devascularization (>50% vs. ≤50%) were compared. RESULTS: Of 84 patients with meningioma undergoing preoperative embolization, 35 (42%) had a postembolization MRI before resection and met study inclusion criteria. The mean tumor diameter was 4.9 ± 1.3 cm, and mean intraoperative EBL was 576 ± 341 mL. Compared with MRI, angiography overestimated devascularization in 22 patients (63%). Using pre- versus postembolization MRIs, 17 (49%) patients had a >50% decrease in enhancement, which was associated with lower mean intraoperative blood loss (444 ± 255 mL) compared with 17 patients with ≤50% devascularization (700 ± 374 mL) (P = 0.03). On angiography, the 22 (63%) patients who demonstrated >50% devascularization during embolization did not statistically differ in intraoperative EBL when compared with 13 (37%) patients with <50% angiographic devascularization. Patients with a ≤50% decrease in contrast enhancement on postembolization MRI were 9 times more likely to lose >500 mL blood intraoperatively during resection (95% confidence interval 1.6-54, P = 0.01). CONCLUSIONS: Postembolization contrast-enhanced MRI is a better predictor of intraoperative blood loss during meningioma resection than postembolization angiography, which overestimates the degree of embolic devascularization. Postembolization preoperative MRI is warranted for optimal patient management.


Asunto(s)
Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Embolización Terapéutica/métodos , Neoplasias Meníngeas/terapia , Meningioma/terapia , Angiografía/métodos , Medios de Contraste , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Neoplasias Meníngeas/irrigación sanguínea , Meningioma/irrigación sanguínea , Persona de Mediana Edad , Cuidados Preoperatorios/métodos , Estudios Retrospectivos
18.
J Neurointerv Surg ; 12(6): 611-615, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31843764

RESUMEN

BACKGROUND: The transradial artery (TRA) approach for neuroendovascular procedures continues to gain popularity, but neurointerventionalists still lag behind interventional cardiologists in the adoption of a TRA-first approach. This study compares the complications and efficiency of the TRA approach to the standard transfemoral artery (TFA) approach at our institution during our initial phase of adopting a TRA-first approach. METHODS: A retrospective analysis was performed on all consecutive neuroangiographic procedures performed at a large cerebrovascular center from October 1, 2018 to June 30, 2019. The standard TFA approach was compared with TRA access, with the primary outcome of complications analyzed via a propensity-adjusted analysis. RESULTS: A total of 1050 consecutive procedures were performed on 877 patients during this 9-month period; 206 (20%) procedures were performed via TRA and 844 (80%) via TFA. The overall complication rate was significantly higher with the TFA procedures than with the TRA procedures (7% (60/844) vs 2% (4/206), respectively; p=0.003). A propensity-adjusted analysis showed that the TFA approach was a significant risk factor for a complication (OR 3.6, 95% CI 1.3 to 10.2, p=0.01). However, the propensity analysis showed that fluoroscopy times were on average 4 min less for TFA procedures than for TRA procedures (p=0.003). CONCLUSION: The TRA approach for neuroendovascular procedures appears to be safer than the TFA approach. Although a steep learning curve is initially encountered when adopting the TRA approach, the transition to a TRA-first practice can be performed safely for neurointerventional procedures and may reduce complications.


Asunto(s)
Procedimientos Endovasculares/efectos adversos , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Complicaciones Intraoperatorias/diagnóstico por imagen , Arteria Radial/diagnóstico por imagen , Arteria Radial/cirugía , Adulto , Anciano , Procedimientos Endovasculares/métodos , Femenino , Humanos , Complicaciones Intraoperatorias/etiología , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo
19.
J Neurointerv Surg ; 12(2): 165-169, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31320550

RESUMEN

BACKGROUND: The selective posterior cerebral artery (PCA) amobarbital test, or PCA Wada test, is used to predict memory impairment after epilepsy surgery in patients who have previously had a failed internal carotid artery (ICA) amobarbital test. METHODS: Medical records from 2012 to 2018 were retrospectively reviewed for all patients with seizures who underwent a selective PCA Wada test at our institution following a failed or inconclusive ICA Wada test. Standardized neuropsychological testing was performed before and during the Wada procedure and postoperatively in patients who underwent resection. RESULTS: Thirty-three patients underwent a selective PCA Wada test, with no complications. Twenty-six patients with medically refractory epilepsy had a seizure focus amenable to selective amygdalohippocampectomy (AHE). Six patients (23%, n=26) had a failed PCA Wada test and did not undergo selective AHE, seven (27%) declined surgical resection, leaving 13 patients who underwent subtemporal selective AHE. Hippocampal sclerosis was found in all 13 patients (100%). Twelve patients (92%) subsequently underwent formal neuropsychological testing and all were found to have stable memory. Ten patients (77%) were seizure-free (Engel Class I), with average follow-up of 13 months. CONCLUSION: The selective PCA Wada test is predictive of memory outcomes after subtemporal selective AHE in patients with a failed or inconclusive ICA Wada test. Furthermore, given the low risk of complications and potential benefit of seizure freedom, a selective PCA Wada test may be warranted in patients with medically intractable epilepsy who are candidates for a selective AHE and who have a prior failed or inconclusive ICA Wada test.


Asunto(s)
Amobarbital/farmacología , Amígdala del Cerebelo/cirugía , Hipocampo/cirugía , Memoria/efectos de los fármacos , Pruebas Neuropsicológicas , Arteria Cerebral Posterior/efectos de los fármacos , Adulto , Epilepsia Refractaria/diagnóstico , Epilepsia Refractaria/psicología , Epilepsia Refractaria/cirugía , Femenino , Humanos , Hipnóticos y Sedantes/farmacología , Masculino , Memoria/fisiología , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/etiología , Trastornos de la Memoria/psicología , Persona de Mediana Edad , Arteria Cerebral Posterior/fisiología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/psicología , Valor Predictivo de las Pruebas , Estudios Retrospectivos
20.
Phys Rev Lett ; 123(14): 140503, 2019 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-31702186

RESUMEN

We present a method that allows the study of classical and quantum correlations in networks with causally independent parties, such as the scenario underlying entanglement swapping. By imposing relaxations of factorization constraints in a form compatible with semidefinite programing, it enables the use of the Navascués-Pironio-Acín hierarchy in complex quantum networks. We first show how the technique successfully identifies correlations not attainable in the entanglement-swapping scenario. Then we use it to show how the nonlocal power of measurements can be activated in a network: there exist measuring devices that, despite being unable to generate nonlocal correlations in the standard Bell scenario, provide a classical-quantum separation in an entanglement swapping configuration.

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