Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Alzheimers Dement ; 20(8): 5281-5289, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38951718

RESUMEN

INTRODUCTION: Vascular contributions to cognitive impairment and dementia (VCID) represent a major factor in cognitive decline in older adults. The present study examined the relationship between cerebrovascular reactivity (CVR) measured by magnetic resonance imaging (MRI) and cognitive function in a multi-site study, using a predefined hypothesis. METHODS: We conducted the study in a total of three analysis sites and 263 subjects. Each site performed an identical CVR MRI procedure using 5% carbon dioxide inhalation. A global cognitive measure of Montreal Cognitive Assessment (MoCA) and an executive function measure of item response theory (IRT) score were used as outcomes. RESULTS: CVR and MoCA were positively associated, and this relationship was reproduced at all analysis sites. CVR was found to be positively associated with executive function. DISCUSSION: The predefined hypothesis on the association between CVR and a global cognitive score was validated in three independent analysis sites, providing support for CVR as a biomarker in VCID. HIGHLIGHTS: This study measured a novel functional index of small arteries referred to as cerebrovascular reactivity (CVR). CVR was positively associated with global cognition in older adults. This finding was observed in three independent cohorts at three sites. Our statistical analysis plan was predefined before beginning data collection.


Asunto(s)
Biomarcadores , Enfermedades de los Pequeños Vasos Cerebrales , Disfunción Cognitiva , Imagen por Resonancia Magnética , Humanos , Masculino , Femenino , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Anciano , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/fisiopatología , Circulación Cerebrovascular/fisiología , Función Ejecutiva/fisiología , Pruebas de Estado Mental y Demencia/estadística & datos numéricos , Pruebas Neuropsicológicas/estadística & datos numéricos
2.
Neuroimage ; 245: 118754, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34826595

RESUMEN

Cerebrovascular reactivity (CVR), which measures the ability of cerebral blood vessels to dilate or constrict in response to vasoactive stimuli such as CO2 inhalation, is an important index of the brain's vascular health. Quantification of CVR using BOLD MRI with hypercapnia challenge has shown great promises in research and clinical studies. However, in order for it to be used as a potential imaging biomarker in large-scale and multi-site studies, the reliability of CO2-CVR quantification across different MRI acquisition platforms and researchers/raters must be examined. The goal of this report from the MarkVCID small vessel disease biomarkers consortium is to evaluate the reliability of CO2-CVR quantification in three studies. First, the inter-rater reliability of CO2-CVR data processing was evaluated by having raters from 5 MarkVCID sites process the same 30 CVR datasets using a cloud-based CVR data processing pipeline. Second, the inter-scanner reproducibility of CO2-CVR quantification was assessed in 10 young subjects across two scanners of different vendors. Third, test-retest repeatability was evaluated in 20 elderly subjects from 4 sites with a scan interval of less than 2 weeks. In all studies, the CO2 CVR measurements were performed using the fixed inspiration method, where the subjects wore a nose clip and a mouthpiece and breathed room air and 5% CO2 air contained in a Douglas bag alternatively through their mouth. The results showed that the inter-rater CoV of CVR processing was 0.08 ± 0.08% for whole-brain CVR values and ranged from 0.16% to 0.88% in major brain regions, with ICC of absolute agreement above 0.9959 for all brain regions. Inter-scanner CoV was found to be 6.90 ± 5.08% for whole-brain CVR values, and ranged from 4.69% to 12.71% in major brain regions, which are comparable to intra-session CoVs obtained from the same scanners on the same day. ICC of consistency between the two scanners was 0.8498 for whole-brain CVR and ranged from 0.8052 to 0.9185 across major brain regions. In the test-retest evaluation, test-retest CoV across different days was found to be 18.29 ± 17.12% for whole-brain CVR values, and ranged from 16.58% to 19.52% in major brain regions, with ICC of absolute agreement ranged from 0.6480 to 0.7785. These results demonstrated good inter-rater, inter-scanner, and test-retest reliability in healthy volunteers, and suggested that CO2-CVR has suitable instrumental properties for use as an imaging biomarker of cerebrovascular function in multi-site and longitudinal observational studies and clinical trials.


Asunto(s)
Circulación Cerebrovascular , Hipercapnia/diagnóstico por imagen , Administración por Inhalación , Anciano , Envejecimiento , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Dióxido de Carbono/farmacología , Femenino , Voluntarios Sanos , Humanos , Hipercapnia/metabolismo , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Adulto Joven
3.
Molecules ; 23(9)2018 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-30200551

RESUMEN

With the aim improving drug delivery, liposomes have been employed as carriers for chemotherapeutics achieving promising results; their co-encapsulation with magnetic nanoparticles is evaluated in this work. The objective of this study was to examine the physicochemical characteristics, the pharmacokinetic behaviour, and the efficacy of pegylated liposomes loaded with cisplatin and magnetic nanoparticles (magnetite) (Cis-MLs). Cis-MLs were prepared by a modified reverse-phase evaporation method. To characterize their physicochemical properties, an evaluation was made of particle size, ζ-potential, phospholipid and cholesterol concentration, phase transition temperature (Tm), the encapsulation efficiency of cisplatin and magnetite, and drug release profiles. Additionally, pharmacokinetic studies were conducted on normal Wistar rats, while apoptosis and the cytotoxic effect were assessed with HeLa cells. We present a method for simultaneously encapsulating cisplatin at the core and also embedding magnetite nanoparticles on the membrane of liposomes with a mean vesicular size of 104.4 ± 11.5 nm and a ζ-potential of -40.5 ± 0.8 mV, affording a stable formulation with a safe pharmacokinetic profile. These liposomes elicited a significant effect on cell viability and triggered apoptosis in HeLa cells.


Asunto(s)
Cisplatino/farmacología , Sistemas de Liberación de Medicamentos , Nanopartículas de Magnetita/química , Neoplasias/tratamiento farmacológico , Animales , Supervivencia Celular/efectos de los fármacos , Cisplatino/química , Cisplatino/farmacocinética , Liberación de Fármacos , Células HeLa , Humanos , Liposomas/química , Liposomas/farmacología , Neoplasias/patología , Polietilenglicoles/química , Polietilenglicoles/farmacología , Ratas , Ratas Wistar
4.
Radiology ; 281(2): 516-526, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27351678

RESUMEN

Purpose To investigate the sustained-attention and memory-enhancing neural correlates of the oral administration of methylene blue in the healthy human brain. Materials and Methods The institutional review board approved this prospective, HIPAA-compliant, randomized, double-blinded, placebo-controlled clinical trial, and all patients provided informed consent. Twenty-six subjects (age range, 22-62 years) were enrolled. Functional magnetic resonance (MR) imaging was performed with a psychomotor vigilance task (sustained attention) and delayed match-to-sample tasks (short-term memory) before and 1 hour after administration of low-dose methylene blue or a placebo. Cerebrovascular reactivity effects were also measured with the carbon dioxide challenge, in which a 2 × 2 repeated-measures analysis of variance was performed with a drug (methylene blue vs placebo) and time (before vs after administration of the drug) as factors to assess drug × time between group interactions. Multiple comparison correction was applied, with cluster-corrected P < .05 indicating a significant difference. Results Administration of methylene blue increased response in the bilateral insular cortex during a psychomotor vigilance task (Z = 2.9-3.4, P = .01-.008) and functional MR imaging response during a short-term memory task involving the prefrontal, parietal, and occipital cortex (Z = 2.9-4.2, P = .03-.0003). Methylene blue was also associated with a 7% increase in correct responses during memory retrieval (P = .01). Conclusion Low-dose methylene blue can increase functional MR imaging activity during sustained attention and short-term memory tasks and enhance memory retrieval. © RSNA, 2016 Online supplemental material is available for this article.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Imagen por Resonancia Magnética/métodos , Azul de Metileno/farmacología , Desempeño Psicomotor/efectos de los fármacos , Administración Oral , Adulto , Atención , Método Doble Ciego , Inhibidores Enzimáticos/administración & dosificación , Femenino , Voluntarios Sanos , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Memoria a Corto Plazo , Azul de Metileno/administración & dosificación , Persona de Mediana Edad , Estudios Prospectivos , Análisis y Desempeño de Tareas
5.
Clin Neurol Neurosurg ; 236: 108116, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38244414

RESUMEN

BACKGROUND: Acute tandem occlusions (TOs) are challenging to treat. Although acute carotid stenting of the proximal lesion is well tolerated, there are certain situations when the practitioner may be wary of acute stenting (bleeding concerns). OBJECTIVE: The purpose of this study was to retrospectively study patients with tandem occlusions who had re-occlusion of the extracranial ICA and develop a Circle of Willis Score (COWS) to help predict which patients could forego acute stenting. METHODS: This is a retrospective review of TO patients with a persistent proximal occlusion following intervention (either expected or unexpected). Pre intervention CTA and intraoperative DSA were reviewed, and each patient was assigned a score 2 (complete COW), 1a (patent A1-Acomm-A1), 1p (patent Pcomm), or 0 (incomplete COW). Findings from the DSA took precedence over the CTA. Two cohorts were created, the complete COW cohort (COWS 2) versus the incomplete COW cohort (COWS 1a,1p, or 0). Angiographic outcomes were assessed using the mTICI score (2b-3) and clinical outcomes were assessed using discharge mRS (good outcome mRS 0-3). RESULTS: Of 68 TO cases, 12 had persistent proximal occlusions. There were 5/12 (42 %) patients in the complete COW cohort, and 7/12 (58 %) in the incomplete COW cohort (5/12 with scores of 1a/1p and 2/12 with a score of 0). In the complete COW cohort, there were 2 ICA-ICA and 3 ICA-MCA occlusions. In the incomplete COW cohort, there was one ICA-ICA occlusion and 6 ICA-MCA occlusions. LKW-puncture was shorter in the complete COW cohort (208 min vs. 464 min, p = 0.16). Successful reperfusion was higher in the complete COW cohort (100 % vs. 71 %). There was a trend toward better clinical outcomes in the complete COW cohort (80 % vs 29 %, p = 0.079). CONCLUSION: The COWS is a simple score that may help predict a successful clinical outcome without proximal revascularization when concerned about performing an acute carotid stent during TO treatment. Evaluation in larger TO cohort is warranted.


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/cirugía , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/cirugía , Estudios Retrospectivos , Círculo Arterial Cerebral/diagnóstico por imagen , Círculo Arterial Cerebral/cirugía , Resultado del Tratamiento , Toma de Decisiones , Stents , Trombectomía
6.
Development ; 137(24): 4171-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21068065

RESUMEN

The stratification and differentiation of the epidermis are known to involve the precise control of multiple signaling pathways. By contrast, little is known about the development of the mouse esophagus and forestomach, which are composed of a stratified squamous epithelium. Based on prior work in the skin, we hypothesized that bone morphogenetic protein (BMP) signaling is a central player. To test this hypothesis, we first used a BMP reporter mouse line harboring a BRE-lacZ allele, along with in situ hybridization to localize transcripts for BMP signaling components, including various antagonists. We then exploited a Shh-Cre allele that drives recombination in the embryonic foregut epithelium to generate gain- or loss-of-function models for the Bmpr1a (Alk3) receptor. In gain-of-function (Shh-Cre;Rosa26(CAG-loxpstoploxp-caBmprIa)) embryos, high levels of ectopic BMP signaling stall the transition from simple columnar to multilayered undifferentiated epithelium in the esophagus and forestomach. In loss-of-function experiments, conditional deletion of the BMP receptor in Shh-Cre;Bmpr1a(flox/flox) embryos allows the formation of a multilayered squamous epithelium but this fails to differentiate, as shown by the absence of expression of the suprabasal markers loricrin and involucrin. Together, these findings suggest multiple roles for BMP signaling in the developing esophagus and forestomach.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Esófago/citología , Esófago/metabolismo , Mucosa Gástrica/metabolismo , Transducción de Señal/fisiología , Estómago/citología , Animales , Receptores de Proteínas Morfogenéticas Óseas/genética , Receptores de Proteínas Morfogenéticas Óseas/metabolismo , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/metabolismo , Proteínas Morfogenéticas Óseas/genética , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Epitelio/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Inmunohistoquímica , Hibridación in Situ , Ratones , Transducción de Señal/genética
7.
Interv Neuroradiol ; : 15910199231151274, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658788

RESUMEN

BACKGROUND: Repeat angiography will identify vascular pathology in approximately 10% of cases following angiogram-negative subarachnoid hemorrhage (anSAH), but small atypical aneurysms of the basilar artery are very uncommon. OBJECTIVE: To report a case series of delayed appearance of nontraumatic basilar artery small atypical aneurysms. METHODS: IRB approval was obtained for this retrospective case series and patient consent was waived. RESULTS: Herein we report three cases of spontaneous anSAH, all of whom had a negative digital subtraction angiogram (DSA) on admission and all of whom had appearance of a small atypical aneurysms of the upper basilar trunk/apex on follow-up imaging (two during the initial admission and one in a delayed fashion). All three patients were ultimately treated with flow diversion (although one patient underwent attempted coiling that was abandoned due to inability to catheterize the aneurysm). CONCLUSION: This report highlights the importance of a repeat DSA in cases of anSAH as well as the importance of scrutinizing the basilar trunk for these very small atypical aneurysms that may go unnoticed.

8.
J Imaging ; 9(3)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36976122

RESUMEN

Post-chemotherapy retroperitoneal lymph node dissection (PC-RPLND) in non-seminomatous germ-cell tumor (NSTGCTs) is a complex procedure. We evaluated whether 3D computed tomography (CT) rendering and their radiomic analysis help predict resectability by junior surgeons. The ambispective analysis was performed between 2016-2021. A prospective group (A) of 30 patients undergoing CT was segmented using the 3D Slicer software while a retrospective group (B) of 30 patients was evaluated with conventional CT (without 3D reconstruction). CatFisher's exact test showed a p-value of 0.13 for group A and 1.0 for Group B. The difference between the proportion test showed a p-value of 0.009149 (IC 0.1-0.63). The proportion of the correct classification showed a p-value of 0.645 (IC 0.55-0.87) for A, and 0.275 (IC 0.11-0.43) for Group B. Furthermore, 13 shape features were extracted: elongation, flatness, volume, sphericity, and surface area, among others. Performing a logistic regression with the entire dataset, n = 60, the results were: Accuracy: 0.7 and Precision: 0.65. Using n = 30 randomly chosen, the best result obtained was Accuracy: 0.73 and Precision: 0.83, with a p-value: 0.025 for Fisher's exact test. In conclusion, the results showed a significant difference in the prediction of resectability with conventional CT versus 3D reconstruction by junior surgeons versus experienced surgeons. Radiomic features used to elaborate an artificial intelligence model improve the prediction of resectability. The proposed model could be of great support in a university hospital, allowing it to plan the surgery and to anticipate complications.

9.
J Imaging ; 9(10)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37888320

RESUMEN

BACKGROUND: The identification of histopathology in metastatic non-seminomatous testicular germ cell tumors (TGCT) before post-chemotherapy retroperitoneal lymph node dissection (PC-RPLND) holds significant potential to reduce treatment-related morbidity in young patients, addressing an important survivorship concern. AIM: To explore this possibility, we conducted a study investigating the role of computed tomography (CT) radiomics models that integrate clinical predictors, enabling personalized prediction of histopathology in metastatic non-seminomatous TGCT patients prior to PC-RPLND. In this retrospective study, we included a cohort of 122 patients. METHODS: Using dedicated radiomics software, we segmented the targets and extracted quantitative features from the CT images. Subsequently, we employed feature selection techniques and developed radiomics-based machine learning models to predict histological subtypes. To ensure the robustness of our procedure, we implemented a 5-fold cross-validation approach. When evaluating the models' performance, we measured metrics such as the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, precision, and F-score. RESULT: Our radiomics model based on the Support Vector Machine achieved an optimal average AUC of 0.945. CONCLUSIONS: The presented CT-based radiomics model can potentially serve as a non-invasive tool to predict histopathological outcomes, differentiating among fibrosis/necrosis, teratoma, and viable tumor in metastatic non-seminomatous TGCT before PC-RPLND. It has the potential to be considered a promising tool to mitigate the risk of over- or under-treatment in young patients, although multi-center validation is critical to confirm the clinical utility of the proposed radiomics workflow.

10.
J Clin Neurosci ; 103: 148-152, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35878541

RESUMEN

BACKGROUND: Understanding the rupture risk of unruptured intracranial aneurysms has important clinical implications given the morbidity and mortality associated with subarachnoid hemorrhage (SAH). The ISUIA, UCAS, and PHASES studies provide rupture risk calculations. OBJECTIVE: We apply the risk calculations to a series ruptured intracranial aneurysms to assess the rupture risk for each aneurysm (had they been discovered in the unruptured state). METHODS: This is a retrospective study of 246 patients with SAH from a ruptured saccular aneurysm. The ISUIA, UCAS, and PHASES calculators were applied to each patient/aneurysm to demonstrate a theoretical annual risk of rupture dichotomized by aneurysm location. RESULTS: The average diameter of the aneurysms was 5.5 ± 3.1 mm. Three quarters (75%) of the aneurysms measured <7 mm and 48.8% were <5 mm. The anterior communicating artery (Acomm) was the most common location of rupture (24.7%). Posterior communicating artery aneurysms (Pcomm) were the third most common at 16.2%. The average ISUIA 1-year rupture risk was 0.46 ± 0.008%. The average UCAS 1-year rupture risk was 0.93% ± 0.01. The annualPHASESrupture risk was0.32 ± 0.004%. The highest risk locations were the vertebral artery (up to 10.3% per year) and superior cerebellar artery (up to 2.7% per year). On average, Acomm aneurysms had 1 year risk no higher than 1.1% and Pcomm aneurysms no higher than 1.2% per year. CONCLUSION: We observed that in a small retrospective series of ruptured aneurysms, the majority were <7 mm and that the theoretical rupture risk of these aneurysms, had they been discovered in the unruptured state, is low (<1% per year). Our study has a number of limitations and these results should be validated in a larger multicenter study.


Asunto(s)
Aneurisma Roto , Aneurisma Intracraneal , Hemorragia Subaracnoidea , Humanos , Estudios Retrospectivos , Factores de Riesgo
11.
Neurohospitalist ; 12(1): 155-161, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34950406

RESUMEN

The artery of Davidoff and Schechter (ADS) is the only meningeal branch of the posterior cerebral artery (PCA), supplying the medial tentorial margin and posterior portions of the falx. Given its small size, it is rarely identified on angiographic studies, unless enlarged in pathologies such as dural arteriovenous fistulas (DAVFs) or vascularized masses. This artery was first described by Wollschlaeger and Wollschlaeger in 1965, and to date, only a few reports have described its significance. The objective of this study is to report our experience with the ADS in dural fistulas from 2 tertiary medical centers and to emphasize the importance of recognizing this artery during angiographic examination of vascular tentorial and posterior fossa lesions. To our knowledge, this report demonstrates the largest angiographic case series published to date, recognizing a total of 7 patients with ADS arising secondary to a posterior fossa or tentorial DAVF and one of the largest reported series of DAVFs supplied by the ADS treated by endovascular and surgical techniques. Our cases validate the importance of prompt identification of the ADS for the diagnosis as well as endovascular treatment of vascular malformations in the posterior fossa and tentorial region.

12.
Pharmaceutics ; 14(8)2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-36015277

RESUMEN

In the present work, we propose the development of a novel carrier that does not need organic solvents for its preparation and with the potential for the intravenous delivery of lipophilic and hydrophilic drugs. Named lipomics, this is a mixed colloid of micelles incorporated within a liposome. This system was designed through ternary diagrams and characterized by physicochemical techniques to determine the particle size, zeta potential, shape, morphology, and stability properties. The lipomics were subjected to electron microscopy (SEM, TEM, and STEM) to evaluate their physical size and morphology. Finally, pharmacokinetic studies were performed by radiolabeling the lipomics with Technetium-99m chelated with BMEDA to evaluate the in vivo biodistribution through techniques of molecular imaging (microSPECT/CT) in rats. Radiolabeling efficiency was used to compare the encapsulation efficiency of the hydrophilic and lipophilic molecules in lipomics and liposomes. According to the results, lipomics are potentially carriers of lipophilic and hydrophilic drugs.

13.
Clin Neurol Neurosurg ; 209: 106906, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34482116

RESUMEN

Ruptured choroidal microaneurysms associated with moyamoya syndrome are rare entities. Their small size and deep/distal location make them challenging to treat. Both surgical and endovascular treatment options carry significant risk of stroke. Here we present a two-patient case report of ruptured choroidal microaneurysms treated with Nbutyl cyanoacrylate (nBCA) endovascular embolization utilizing neuromonitoring and provocative testing during one of the cases. We also present a review of the literature evaluating surgical and endovascular treatment of these aneurysms.


Asunto(s)
Aneurisma Roto/terapia , Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal/terapia , Enfermedad de Moyamoya/complicaciones , Adulto , Aneurisma Roto/diagnóstico por imagen , Aneurisma Roto/etiología , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/etiología , Masculino , Enfermedad de Moyamoya/diagnóstico por imagen , Resultado del Tratamiento
14.
World Neurosurg ; 145: 51-56, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32916357

RESUMEN

BACKGROUND: Flow diversion with or without coil embolization has become the first-line treatment for large or giant paraclinoid internal carotid artery intracranial aneurysms. Oftentimes, these sizable aneurysms impose anatomical challenges to endovascular treatment through limiting both distal outflow access and maintenance of distal vessel purchase during catheter reduction, which are required for successful stent placement. Various strategies to obtain and maintain distal access within the parent vessel have been described previously; however, new techniques may need to be employed when more standard maneuvers fail. CASE DESCRIPTION: This paper depicts a case of successful flow diversion of a near-giant internal carotid artery ophthalmic aneurysm in a middle-aged female patient using a balloon-assisted technique, designated the Ricochet-Scepter technique, to achieve distal outflow access followed by secondary system reduction via a stent retriever after standard maneuvers had failed. CONCLUSIONS: Giant, wide-neck aneurysms present treatment challenges that may require using adjunctive devices and advanced endovascular techniques. When routine strategies for gaining distal outflow access fail, the Ricochet-Scepter technique is a viable option for achieving distal access.


Asunto(s)
Oclusión con Balón/métodos , Enfermedades de las Arterias Carótidas/cirugía , Arteria Carótida Interna/cirugía , Procedimientos Endovasculares/métodos , Aneurisma Intracraneal/cirugía , Procedimientos Neuroquirúrgicos/métodos , Arteria Oftálmica/cirugía , Angiografía de Substracción Digital , Prótesis Vascular , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Arteria Carótida Interna/diagnóstico por imagen , Angiografía por Tomografía Computarizada , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Persona de Mediana Edad , Arteria Oftálmica/diagnóstico por imagen , Stents , Resultado del Tratamiento
15.
Neurohospitalist ; 11(1): 33-39, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33868554

RESUMEN

The differential diagnosis for bilateral thalamic edema is extensive and includes vascular, neoplastic, metabolic, and infectious causes. Of the vascular causes of thalamic edema, arterial and venous infarctions are well-documented, but dural arteriovenous fistulas (dAVFs) are a relatively uncommon and widely underrecognized cause of thalamic edema. Dural AVFs are notoriously difficult to diagnose clinically, especially in the absence of hemorrhage, and cross-sectional imaging findings can be subtle. This can result in a delayed diagnosis, and occasionally, an invasive biopsy for further clarification of a purely vascular disease. In this review, we detail our experience with the imaging diagnosis of dAVF as a cause of thalamic edema and present a short differential of other vascular causes.

16.
J Neurosurg ; : 1-8, 2021 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-34952522

RESUMEN

OBJECTIVE: Numerous techniques have been developed to treat wide-neck aneurysms (WNAs), each with different safety and efficacy profiles. Few studies have compared endovascular therapy (EVT) with microsurgery (MS). The authors' objective was to perform a prospective multicenter study of a WNA registry using rigorous outcome assessments and to compare EVT and MS using propensity score analysis (PSA). METHODS: Unruptured, saccular, not previously treated WNAs were included. WNA was defined as an aneurysm with a neck width ≥ 4 mm or a dome-to-neck ratio (DTNR) < 2. The primary outcome was modified Rankin Scale (mRS) score at 1 year after treatment (good outcome was defined as mRS score 0-2), as assessed by blinded research nurses and compared with PSA. Angiographic outcome was assessed using the Raymond scale with core laboratory review (adequate occlusion was defined as Raymond scale score 1-2). RESULTS: The analysis included 224 unruptured aneurysms in the EVT cohort (n = 140) and MS cohort (n = 84). There were no differences in baseline demographic characteristics, such as proportion of patients with good baseline mRS score (94.3% of the EVT cohort vs 94.0% of the MS cohort, p = 0.941). WNA inclusion criteria were similar between cohorts, with the most common being both neck width ≥ 4 mm and DTNR < 2 (50.7% of the EVT cohort vs 50.0% of the MS cohort, p = 0.228). More paraclinoid (32.1% vs 9.5%) and basilar tip (7.1% vs 3.6%) aneurysms were treated with EVT, whereas more middle cerebral artery (13.6% vs 42.9%) and pericallosal (1.4% vs 4.8%) aneurysms were treated with MS (p < 0.001). EVT aneurysms were slightly larger (p = 0.040), and MS aneurysms had a slightly lower mean DTNR (1.4 for the EVT cohort vs 1.3 for the MS cohort, p = 0.010). Within the EVT cohort, 9.3% of patients underwent stand-alone coiling, 17.1% balloon-assisted coiling, 34.3% stent-assisted coiling, 37.1% flow diversion, and 2.1% PulseRider-assisted coiling. Neurological morbidity secondary to a procedural complication was more common in the MS cohort (10.3% vs 1.4%, p = 0.003). One-year mRS scores were assessed for 218 patients (97.3%), and no significantly increased risk of poor clinical outcome was found for the MS cohort (OR 2.17, 95% CI 0.84-5.60, p = 0.110). In an unadjusted direct comparison, more patients in the EVT cohort achieved a good clinical outcome at 1 year (93.4% vs 84.1%, p = 0.048). Final adequate angiographic outcome was superior in the MS cohort (97.6% of the MS cohort vs 86.5% of the EVT cohort, p = 0.007). CONCLUSIONS: Although the treatments for unruptured WNA had similar clinical outcomes according to PSA, there were fewer complications and superior clinical outcome in the EVT cohort and superior angiographic outcomes in the MS cohort according to the unadjusted analysis. These results may be considered when selecting treatment modalities for patients with unruptured WNAs.

17.
J Neurosurg ; : 1-8, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34740187

RESUMEN

OBJECTIVE: Randomized controlled trials have demonstrated the superiority of endovascular therapy (EVT) compared to microsurgery (MS) for ruptured aneurysms suitable for treatment or when therapy is broadly offered to all presenting aneurysms; however, wide neck aneurysms (WNAs) are a challenging subset that require more advanced techniques and warrant further investigation. Herein, the authors sought to investigate a prospective, multicenter WNA registry using rigorous outcome assessments and compare EVT and MS using propensity score analysis (PSA). METHODS: Untreated, ruptured, saccular WNAs were included in the analysis. A WNA was defined as having a neck ≥ 4 mm or a dome/neck ratio (DNR) < 2. The primary outcome was the modified Rankin Scale (mRS) score at 1 year posttreatment, as assessed by blinded research nurses (good outcome: mRS scores 0-2) and compared using PSA. RESULTS: The analysis included 87 ruptured aneurysms: 55 in the EVT cohort and 32 in the MS cohort. Demographics were similar in the two cohorts, including Hunt and Hess grade (p = 0.144) and modified Fisher grade (p = 0.475). WNA type inclusion criteria were similar in the two cohorts, with the most common type having a DNR < 2 (EVT 60.0% vs MS 62.5%). More anterior communicating artery aneurysms (27.3% vs 18.8%) and posterior circulation aneurysms (18.2% vs 0.0%) were treated with EVT, whereas more middle cerebral artery aneurysms were treated with MS (34.4% vs 18.2%, p = 0.025). Within the EVT cohort, 43.6% underwent stand-alone coiling, 50.9% balloon-assisted coiling, 3.6% stent-assisted coiling, and 1.8% flow diversion. The 1-year mRS score was assessed in 81 patients (93.1%), and the primary outcome demonstrated no increased risk for a poor outcome with MS compared to EVT (OR 0.43, 95% CI 0.13-1.45, p = 0.177). The durability of MS was higher, as evidenced by retreatment rates of 12.7% and 0% for EVT and MS, respectively (p = 0.04). CONCLUSIONS: EVT and MS had similar clinical outcomes at 1 year following ruptured WNA treatment. Because of their challenging anatomy, WNAs may represent a population in which EVT's previously demonstrated superiority for ruptured aneurysm treatment is less relevant. Further investigation into the treatment of ruptured WNAs is warranted.

18.
J Glaucoma ; 26(5): 430-437, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28221328

RESUMEN

PURPOSE: To investigate retinotopic functional representation in the visual cortex of mild to moderate primary open-angle glaucoma (POAG) participants and age-matched normal volunteers using high-resolution retinotopic blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI). METHODS: fMRI was performed on 9 POAG participants (61±11 y old) and 9 age-matched controls (58±5 y old) were studied. A wide-view visual presentation (±55 degrees) was used to evaluate central and peripheral vision. Cortical magnification factors and BOLD% changes as a function of eccentricity. Correlation analysis between BOLD% changes and visual field scores, and between BOLD% changes and retinal nerve fiber layer thicknesses was performed. Comparison of BOLD% changes for individual visual field quadrants between POAG subgroups and normal group was performed. RESULTS: BOLD% changes of POAG participants in peripheral visual regions were reduced compared to normals but similar in central visual regions, consistent with the notion of peripheral vision being affected first and more compared to central vision. fMRI retinotopic mapping revealed enlarged representation of the parafovea in the visual cortex of POAG participants compared to normals. Cortical magnification of the central, but not peripheral, visual representation in the visual cortex was larger in POAG participants, suggesting functional remapping. BOLD% changes of individual visual field quadrants were significantly correlated with visual field scores and with retinal nerve fiber layer thickness in the corresponding quadrants. CONCLUSIONS: These results support the hypothesis that there are functional alteration and remapping in the topographic representation of the visual cortex in POAG participants, and these changes are correlated with disease severity.


Asunto(s)
Glaucoma de Ángulo Abierto/fisiopatología , Plasticidad Neuronal/fisiología , Nervio Óptico/diagnóstico por imagen , Retina/diagnóstico por imagen , Trastornos de la Visión/diagnóstico , Corteza Visual/fisiología , Adulto , Anciano , Femenino , Humanos , Presión Intraocular/fisiología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Nervio Óptico/fisiopatología , Retina/fisiopatología , Campos Visuales/fisiología
19.
Medisur ; 20(6)dic. 2022.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1440593

RESUMEN

En el contexto de los servicios hospitalarios es importante considerar lo referente a la comunicación externa, dada la necesidad de orientar adecuadamente el vínculo con el resto de la sociedad; en tal sentido, se requiere organizar y promover relaciones con las demás instituciones. Las vías para lograr este propósito son objeto de atención y estudio desde hace varias décadas. Este artículo tiene como objetivo sistematizar el conocimiento sobre estrategias de comunicación externa en los servicios hospitalarios. Se realizó una revisión narrativa en bancos de datos: BVS, PUBMed, y SciELO, según los descriptores indexados. Fueron incluidos en el análisis siete artículos desarrollados en distintos países. Entre los componentes específicos de este tipo de estrategia, se encuentran los diagnósticos organizacionales de información; políticas; estrategias; productos comunicativos, productos y servicios informacionales; estructuras de información, comunicación y sus gestores; programas de formación de competencias; así como control, monitoreo y evaluación de los resultados de cada actividad, junto a la acción de un equipo multidisciplinario que potencia todo ese desarrollo.


In hospital services context, it is important to consider what refers to external communication, given the need to properly guide the link with the rest of society; in this sense, it is necessary to organize and promote relationships with other institutions. The ways to achieve this purpose have been the object of attention and study for several decades. This article aims to systematize knowledge about external communication strategies in hospital services. A narrative review was carried out in data banks: VHL, PubMed, and SciELO, according to the indexed descriptors. Seven articles developed in different countries were included in the analysis. Among the specific components of this type of strategy, there are organizational information diagnoses; policies; strategies; communicative products, informational products and services; information and communication structures and their managers; skills training programs; as well as control, monitoring and evaluation of the results of each activity, together with the action of a multidisciplinary team that enhances all this development.

20.
Brain Imaging Behav ; 11(3): 640-648, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26961091

RESUMEN

Methylene blue USP (MB) is a FDA-grandfathered drug used in clinics to treat methemoglobinemia, carbon monoxide poisoning and cyanide poisoning that has been shown to increase fMRI evoked blood oxygenation level dependent (BOLD) response in rodents. Low dose MB also has memory enhancing effect in rodents and humans. However, the neural correlates of the effects of MB in the human brain are unknown. We tested the hypothesis that a single low oral dose of MB modulates the functional connectivity of neural networks in healthy adults. Task-based and task-free fMRI were performed before and one hour after MB or placebo administration utilizing a randomized, double-blinded, placebo-controlled design. MB administration was associated with a reduction in cerebral blood flow in a task-related network during a visuomotor task, and with stronger resting-state functional connectivity in multiple regions linking perception and memory functions. These findings demonstrate for the first time that low-dose MB can modulate task-related and resting-state neural networks in the human brain. These neuroimaging findings support further investigations in healthy and disease populations.


Asunto(s)
Encéfalo/efectos de los fármacos , Azul de Metileno/farmacología , Psicotrópicos/farmacología , Administración Oral , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico , Circulación Cerebrovascular/efectos de los fármacos , Método Doble Ciego , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/fisiología , Pruebas Neuropsicológicas , Descanso , Percepción Visual/efectos de los fármacos , Percepción Visual/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA