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1.
Faraday Discuss ; 243(0): 307-320, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37017214

RESUMEN

Ga was identified earlier as one of the "overlooked" metals for catalyzing the electrochemical nitrogen reduction reaction (ENRR). We investigate here the electrocatalytic activity of Ga towards the nitrogen reduction reaction. We used a combination of molecular modelling and simulations using periodic density functional theory calculations (DFT), and experimental ENRR measurements. The ENRR was found to proceed via an associative mechanism where the first PCET to dinitrogen forming the surface adsorbed N2H* species is the overpotential limiting step. The bare Ga cathode has a high overpotential (>2 V (SHE)) for the ENRR. We also investigated the effect of a water-in-salt electrolyte (WISE) on the rate of ammonia formation. The addition of an Li salt lowers the overpotential to 1.88 V (SHE). DFT calculations revealed that the H-adatom was more favorably bound than the N-adatom, and the hydrogen evolution reaction (HER) is expected to dominate at high cathodic potentials. Experimental ENRR tests corroborate our results wherein no significant NH3 formation was detected. The low electrochemical activity of Ga is attributed to poor binding and activation of N2 which originates from an electropositive surface charge distribution.

2.
Childs Nerv Syst ; 39(4): 963-974, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36571597

RESUMEN

OBJECTIVES: A few previous studies have reported the role of embolization with curative intent in the treatment of the early phase of a spontaneous cerebral hemorrhage in pediatric patients, and its efficacy needs to be compared with surgery at the same time risk factors for hemorrhage following early embolization in such patients need to be evaluated. METHODS: From a pool of 80 pediatric (< 18 years) who had undergone treatment for ruptured AVM with hemorrhage at our center between July 2018 and July 2022, we identified 36 patients with spontaneous bleeding due to AVM. Out of which, 20 were treated solely by embolization (group 1), while the remaining patients were treated surgically (with and without adjuvant embolization) (group 2). RESULT: Spetzler-Martin's grading of the lesion suggested seven lesions < 3 and 13 lesions ≥ 3 in the embolization group. Similarly, seven lesions were < 3 and nine ≥ 3 Spetzler-Martin grade in the surgery group. Incomplete embolization was associated with hemorrhage in two patients treated with curative intent and four patients treated with embolization as adjuvant in the surgery group (p = 0.01). On follow-up, 18 patients in the embolization group and 12 in the surgery group had Glasgow outcome scores ≥ 4 (p = 0.273). CONCLUSION: In the pediatric age group, incomplete embolization is the significant risk factor for hemorrhage in AVMs treated after a hemorrhagic stroke. Embolization with curative intent is as effective as surgery in treating such lesions as adjuvant embolization with careful patient selection.


Asunto(s)
Embolización Terapéutica , Malformaciones Arteriovenosas Intracraneales , Radiocirugia , Humanos , Niño , Microcirugia , Resultado del Tratamiento , Estudios Retrospectivos , Malformaciones Arteriovenosas Intracraneales/complicaciones , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/cirugía , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/etiología , Hemorragia Cerebral/cirugía
3.
Inorg Chem ; 60(5): 3274-3281, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33587616

RESUMEN

The conventional method of assigning formal oxidation states (FOSs) to metals and ligands is an important tool for understanding and predicting the chemical reactivity, in particular, in catalysis research. For complexes containing redox-noninnocent ligands, the oxidation state of the ligand can be ambiguous (i.e., their spectroscopic oxidation state can differ from the FOS) and thus frustrates the assignment of the oxidation state of the metal. A quantitative correlation between the empirical metric data of redox-active ligands and their oxidation states using a metrical oxidation state (MOS) model has been developed for catecholate- and amidophenoxide-derived ligands by Brown. In the present work, we present a MOS model for 1,4-diazabutadiene (DADn) ligands. This model is based on a similar approach as reported by Brown, correlating the intra-ligand bond lengths of the DADn moiety in a quantitative manner with the MOS using geometrical information from X-ray structures in the Cambridge Crystallographic Data Center (CCDC) database. However, an accurate determination of the MOS of these ligands turned out to be dependent on the coordination mode of the DAD2- moiety, which can adopt both a planar κ2-N2-geometry and a η4-N2C2 π-coordination mode in (transition) metal complexes in its doubly reduced, dianionic enediamide oxidation state. A reliable MOS model was developed taking the intrinsic differences in intra-ligand bond distances between these coordination modes of the DAD2- ligand into account. Three different models were defined and tested using different geometric parameters (C═C → M distance, M-N-C angle, and M-N-C-C torsion angle) to describe the C═C backbone coordination with the metal in the η4-N2-C2 π-coordination mode of the DAD2- ligand. Statistical analysis revealed that the C═C → M distance best describes the η4-N2-C2 coordination mode using a cutoff value of 2.46 Å for π-coordination. The developed MOS model was used to validate the oxidation state assignment of elements not contained within the training set (Sr, Yb, and Ho), thus demonstrating the applicability of the MOS model to a wide range of complexes. Chromium complexes with complex electronic structures were also shown to be accurately described by MOS analysis. Furthermore, it is shown that a combination of MOS analysis and FOD calculations provides an inexpensive method to gain insight into the electronic structure of singlet spin state (S = 0) [M(trop2dad)] transition-metal complexes showing (potential) singlet biradical character.

4.
Phys Chem Chem Phys ; 23(4): 2557-2567, 2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-33325474

RESUMEN

Rapid and accurate prediction of reactivity descriptors of transition metal (TM) complexes is a major challenge for contemporary quantum chemistry. The recently-developed GFN2-xTB method based on the density functional tight-binding theory (DFT-B) is suitable for high-throughput calculation of geometries and thermochemistry for TM complexes albeit with moderate accuracy. Herein we present a data-augmented approach to improve substantially the accuracy of the GFN2-xTB method for the prediction of thermochemical properties using pKa values of TM hydrides as a representative model example. We constructed a comprehensive database for ca. 200 TM hydride complexes featuring the experimentally measured pKa values as well as the GFN2-xTB-optimized geometries and various computed electronic and energetic descriptors. The GFN2-xTB results were further refined and validated by DFT calculations with the hybrid PBE0 functional. Our results show that although the GFN2-xTB performs well in most cases, it fails to adequately describe TM complexes featuring multicarbonyl and multihydride ligand environments. The dataset was analyzed with the ordinary least squares (OLS) fitting and was used to construct an automated machine learning (AutoML) approach for the rapid estimation of pKa of TM hydride complexes. The results obtained show a high predictive power of the very fast AutoML model (RMSE ∼ 2.7) comparable to that of the much slower DFT calculations (RMSE ∼ 3). The presented data-augmented quantum chemistry-based approach is promising for high-throughput computational screening workflows of homogeneous TM-based catalysts.

5.
Drug Dev Ind Pharm ; 46(10): 1726-1733, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32892648

RESUMEN

Necessity to develop the efficient targeted delivery of highly potent immunosuppressant for IBD in order to avoid surgical procedure, led to fabrication and evaluation of its anti-inflammatory potential. Previously formulated cyclosporine A (Cyp A) into enteric coated capsules was further evaluated for its site-specificity in the treatment of TNBS induced colitis. Contact angle measurement studies showed excellent spreadability of the developed formulation over the hydrophilic biological tissue substrate. HET-CAM study demonstrates that the formulation prepared is nonirritant to the highly vascular tissues and hence can be used for the immunological sensitive tissues like inflamed intestine in IBD. Further the developed formulation has been characterized for site specificity to distal parts of intestine by pharmacokinetic studies. The appearance of drug in systemic circulation at approximately 5 hours in New Zealand strain of rabbits confirms drug delivery at distal parts of intestine. Significant reduced levels of TNF-α, IL-6 and IL-10 in drug treated animals signifies inhibition of inflammatory reactions at the TNBS treated site. Simultaneously, the change in body weight of same group of animals was observed for 15 days. Results showed a marginal recovery of body weight in Cyp A treated TNBS induced colitis animals. In conclusion, all in vitro and in vivo results confirm the successful site specific delivery and anti-inflammatory efficacy of developed formulation of Cyp A in TNBS induced colitis in New Zealand rabbits.


Asunto(s)
Colitis , Ciclosporina , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Modelos Animales de Enfermedad , Conejos , Ácido Trinitrobencenosulfónico/uso terapéutico , Factor de Necrosis Tumoral alfa/química , Factor de Necrosis Tumoral alfa/fisiología
6.
Inorg Chem ; 58(3): 1935-1948, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30640464

RESUMEN

Iron catalyzed carbon-nitrogen bond formation reactions of a wide variety of nucleophiles and aryl halides using well-defined iron-complexes featuring redox noninnocent 2-(arylazo)-1,10-phenanthroline (L1) ligands are reported. Besides substrate centered C-N coupling, C-N bond formation reactions were also observed at the ortho- and para-positions of the phenyl ring of the coordinated azo-aromatic scaffolds affording new tetradentate ligands, 2-N-aryl-(2-arylazo)-1,10-phenanthroline (L2), and tridentate ligands, 4 -N-aryl-(2-arylazo)-1,10-phenanthroline (L3), respectively. Control experiments and mechanistic studies reveal that the complex [FeL1Cl2] (1) undergoes in situ reduction during the catalytic reaction to produce the monoanionic complex [1]-, which then acts as the active catalyst. The metal (iron) and the coordinated ligand were found to work in a cooperative manner during the transfer processes involved in the fundamental steps of the catalytic cycle. Detailed experimental and theoretical (DFT) studies were performed to get insight into the competitive substrate versus ligand centered amination reactions.

7.
J Am Chem Soc ; 140(40): 13103-13114, 2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30215248

RESUMEN

The mechanism for complete dehydrogenation of aqueous methanol to CO2 and three equivalents of H2 catalyzed by [Ru(trop2dad)] was investigated with DFT (trop2dad = 1,4-bis(5 H-dibenzo[ a, d]cyclohepten-5-yl)-1,4-diazabuta-1,3-diene). To date, this is the only catalyst that promotes the acceptorless dehydrogenation of aqueous methanol in homogeneous phase under mild conditions without the addition of an additive (base, acid, or a secondary catalyst). A detailed understanding of the mechanism of this transformation may therefore be of significant importance for the conversion of liquid organic fuels. Previous computational studies using simplified models of the catalyst suggested entirely ligand-centered reaction pathways with rather high-energy barriers for complete dehydrogenation of aqueous methanol. These are, however, not consistent with the experimental data. In the present paper, we reveal a different reaction mechanism for aqueous methanol dehydrogenation that involves metal-ligand cooperativity involving the diazadiene (dad) ligand and has substantially lower barriers, in good agreement with the experimental data. The dad moiety of the ligand actively participates in the alcohol activation mechanism. In the first step of the reaction, the dad ligand rearranges from a σ- to a π-bound coordination mode. This adjusts the electronic structure of both the metal and the ligand, leading to an enhanced Brønsted basicity of the nitrogen centers and higher Lewis acidity of the ruthenium center. As a result, concerted proton-hydride transfer to/from metal-hydride and N-protonated dad-ligand moieties becomes possible, leading to low-barrier metal-ligand cooperative elementary steps for alcohol activation and H2 elimination.

8.
Chemistry ; 24(21): 5513-5521, 2018 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-29341297

RESUMEN

Coordination of the diazadiene diolefin ligand (trop2 dad) to ruthenium leads to various complexes of composition [Ru(trop2 dad)(L)]. DFT studies indicate that the closed-shell singlet (CSS), open-shell singlet (OSS), and triplet electronic structures of this species are close in energy, with the OSS spin configuration being the lowest in energy for all tested functionals. Singlet-state CASSCF calculations revealed a significant multireference character for these complexes. The closed-shell singlet wavefunction dominates, but these complexes have a significant (≈8-16 %) open-shell singlet [d7 -RuI (L)(trop2 dad.- )] contribution mixed into the ground state. In agreement with their ambivalent electronic structure, these complexes reveal both metal- and ligand-centered reactivity. Most notable are the reactions with AdN3 , diazomethane, and a phosphaalkyne leading to scission of the C-C bond of the diazadiene (dad) moiety of the trop2 dad ligand, resulting in net (formal) nitrene, carbene, or P≡C insertion in the dad C-C bond, respectively. Supporting DFT studies revealed that several of the ligand-based reactions proceed via low-barrier radical-type pathways, involving the dad.- ligand radical character of the OSS or triplet species.

11.
AAPS PharmSciTech ; 19(3): 1264-1273, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29313261

RESUMEN

Aripiprazole (ARP), a second-generation or atypical antipsychotic, is poorly soluble and undergoes extensive hepatic metabolism and P-glycoprotein efflux which lead to reduced in vivo efficacy and increased dose-related side effects. To enhance in vivo efficacy and oral bioavailability of aripiprazole, aripiprazole-loaded solid lipid nanoparticles (SLNs) were developed using tristearin as solid lipid. Tween 80 and sodium taurocholate were used as surfactants to prepare SLNs using microemulsification method. SLNs were characterized for particle size, zeta potential, entrapment efficiency, and crystallinity of lipid and drug. In vitro release studies were performed in water containing 0.5% sodium dodecyl sulfate. Pharmacodynamic evaluation was carried out in laca mice using dizocilpine-induced schizophrenic model where behavioral evaluation revealed better in vivo efficacy of SLNs. Pharmacokinetics of aripiprazole-loaded SLNs after oral administration to conscious male Wistar rats was studied. Bioavailability of aripiprazole was increased 1.6-fold after formulation of aripiprazole into SLNs as compared to plain drug suspension. The results indicated that solid lipid nanoparticles can improve the bioavailability of lipophilic drugs like aripiprazole by enhancement of absorption and minimizing first-pass metabolism.


Asunto(s)
Antipsicóticos/administración & dosificación , Aripiprazol/administración & dosificación , Portadores de Fármacos/química , Administración Oral , Animales , Antipsicóticos/farmacocinética , Antipsicóticos/uso terapéutico , Aripiprazol/farmacocinética , Aripiprazol/uso terapéutico , Disponibilidad Biológica , Masculino , Ratones , Nanopartículas , Tamaño de la Partícula , Ratas , Ratas Wistar , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/metabolismo , Tensoactivos/administración & dosificación , Triglicéridos/química
12.
AAPS PharmSciTech ; 19(2): 881-885, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29043605

RESUMEN

Present study aims at solubilizing slightly water-soluble peptide into a nanosize emulsion which is filled into a hard gelatin capsule in the form of preconcentrate. Further, liquid-filled capsule was dip-coated with ethyl cellulose and Eudragit S100 for colon targeting. An in vitro release profile was studied for selected formulations, i.e., Formulation A (5 mg ethyl cellulose and 40 mg Eudragit S100), Formulation B (10 mg ethyl cellulose and 30 mg Eudragit S100), and Formulation C (10 mg ethyl cellulose and 20 mg Eudragit S100). Formulations B and A showed an immediate release after 5 and 6 h, respectively, which represents ileo-ceacal transit time. The nanosize of emulsion, i.e., below 100 nm, was confirmed by transmission electron microscopy. Also, a phase transition of nanosize emulsion from water in oil to oil in water on dilution with water was observed through TEM. This novel approach of filling poorly water-soluble protein in solubilized form of nanosize emulsion preconcentrate into coated hard gelatin capsules for colon targeting has been reported first time. This approach could be a breakthrough for the better management of local intestinal pathologies.


Asunto(s)
Química Farmacéutica/métodos , Colon , Sistemas de Liberación de Medicamentos/métodos , Inmunosupresores/química , Péptidos/química , Cápsulas , Colon/efectos de los fármacos , Colon/metabolismo , Preparaciones de Acción Retardada/metabolismo , Emulsiones , Inmunosupresores/administración & dosificación , Inmunosupresores/metabolismo , Péptidos/administración & dosificación , Péptidos/metabolismo , Ácidos Polimetacrílicos , Solubilidad , Comprimidos Recubiertos
13.
J Am Chem Soc ; 139(14): 5117-5124, 2017 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-28298089

RESUMEN

Coordination of FeCl3 to the redox-active pyridine-aminophenol ligand NNOH2 in the presence of base and under aerobic conditions generates FeCl2(NNOISQ) (1), featuring high-spin FeIII and an NNOISQ radical ligand. The complex has an overall S = 2 spin state, as deduced from experimental and computational data. The ligand-centered radical couples antiferromagnetically with the Fe center. Readily available, well-defined, and air-stable 1 catalyzes the challenging intramolecular direct C(sp3)-H amination of unactivated organic azides to generate a range of saturated N-heterocycles with the highest turnover number (TON) (1 mol% of 1, 12 h, TON = 62; 0.1 mol% of 1, 7 days, TON = 620) reported to date. The catalyst is easily recycled without noticeable loss of catalytic activity. A detailed kinetic study for C(sp3)-H amination of 1-azido-4-phenylbutane (S1) revealed zero order in the azide substrate and first order in both the catalyst and Boc2O. A cationic iron complex, generated from the neutral precatalyst upon reaction with Boc2O, is proposed as the catalytically active species.

15.
Drug Dev Ind Pharm ; 42(12): 1956-1967, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27143048

RESUMEN

This research focuses on the fabrication and evaluation of solid lipid nanoparticles (SLNs) for improved ocular delivery of voriconazole (VCZ). Compritol and palmitic acid were selected as lipid carriers based on drug solubility and partitioning behavior. Poloxamer and soya lecithin were the choice for surfactant, while sodium taurocholate was used as a co-surfactant. The particle sizes of the SLNs determined by zetasizer and transmission electron microscopy (TEM) were found within the desired range. The in vitro release study of SLNs exhibited a sustained-release property of the drug. The ex vivo studies displayed enhanced corneal drug permeation from SLNs in comparison to the drug suspension. Further, the corneal hydration studies, histopathology and Hen's Egg Test Chorio Allantoic Membrane (HETCAM) assay confirmed the non-irritancy of the nano-formulation. The in vivo study confirmed the higher availability of VCZ (from SLN) in aqueous humor with minimal nasolacrymal drainage in contrast to the drug suspension. A good in-vitro in-vivo correlation (IVIVC) further confirmed the potential of SLN as an effective carrier for ocular delivery.

16.
World Neurosurg ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38960309

RESUMEN

BACKGROUND: Pediatric spontaneous intracranial dissecting aneurysms are rare, but systematic studies comparing hemorrhagic and ischemic presentations are lacking. This study addresses gaps in understanding their epidemiology, clinical presentation, management, and outcome. METHODS: A retrospective analysis of 23 pediatric patients with nontraumatic intracranial dissecting aneurysms treated between July 2018 and December 2023 was conducted. Patients were divided into 2 groups based on presentation: hemorrhagic (n = 16) and ischemic (n = 7). Clinical data were analyzed, including demographics, radiologic findings, treatment modalities, and outcomes. RESULTS: Clinical presentations varied, with limb weakness being more prevalent in hemorrhagic cases (P = 0.014), while headache and seizures were more common in ischemic cases. Angiographic analysis revealed distinct patterns, with hemorrhagic cases showing more distal involvement on vessel segments with stenosis and dilatation (pearl string sign). At the same time, the ischemic group exhibited the double-lumen sign. Various treatments, including microsurgery and endovascular techniques, were utilized, with perioperative complications observed, including one mortality in a hemorrhagic case. Multiple regression analysis identified significant risk factors for perioperative complications, namely, the configuration of the dissecting aneurysm (P = 0.016) and the type of presentation (P = 0.0006). Long-term Glasgow Outcome Scores were comparable, but patients with hemorrhagic manifestations experienced prolonged hospital and ICU stays (P = 0.001). CONCLUSIONS: Pediatric intracranial dissecting aneurysms, particularly hemorrhagic cases, are associated with severe neurologic deficits and higher perioperative complications. Despite similar long-term outcomes, hemorrhagic cases require prolonged hospitalization, increasing treatment costs. Optimizing management strategies for pediatric intracranial dissecting aneurysms, especially those with hemorrhagic features, is essential to improve outcomes and reduce healthcare expenditures.

17.
J Clin Neurosci ; 126: 284-293, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38986339

RESUMEN

BACKGROUND: Multicompartmental lesions within the central nervous system are challenging due to their complex anatomy. This study evaluates the efficacy, safety, and utility of hybrid endoscopic and microsurgery versus endoscope-assisted microsurgery(EAM) for excising these lesions. METHODS: A retrospective comparative analysis was conducted on patients who underwent multicompartmental brain tumor surgery, utilizing either hybrid endoscopic and microsurgical techniques with the Endocameleon Hopkins telescope featuring a rotating lens system and knob (Karl Storz GmbH & Co., Tuttlingen, Germany), alternately used with a microscope (ZEISS PENTERO 800 S) (Group 1, n = 69), or endoscope-assisted microsurgery employing a fully high-definition, 45° angled endoscopic tool, QEVO®, integrated into the digital surgical microscope KINEVO 900 (Carl Zeiss Meditec, Oberkochen, Germany) as a plug-in feature (Group 2, n = 63), from July 2018 to March 2024. Data on demographics, clinical presentation, lesion characteristics, surgical details, and outcomes were meticulously collected and analyzed using rigorous statistical methods, including t-tests and chi-square tests. RESULTS: Compared to Group 2, Group 1 had better ease of dissection and visualization of bleeders (p = 0.01) and fewer postoperative hematomas (p = 0.04). Surgical times were similar (p = 0.134). Postoperative follow-up revealed fewer recurrences in Group 1, though not statistically significant (p = 0.33). Group 1 patients reported higher cosmetic satisfaction and shorter hospital stays (p = 0.002). Logistic regression identified tumor vascularity(p = 0.001) and ease of dissection(p = 0.008) as significant factors for recurrence. CONCLUSIONS: Hybrid endoscopic and microsurgery demonstrated superior intraoperative visualization, ease of dissection, and postoperative outcomes compared to endoscope-assisted microsurgery with the Quevo device. These findings suggest that the integrated approach may offer better outcomes for multicompartmental lesion excision regarding safety, efficacy, and patient satisfaction.

18.
Turk Neurosurg ; 34(4): 716-727, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38874254

RESUMEN

AIM: To compare microsurgical clipping and endovascular therapy (EVT) for the management of shunt-dependent hydrocephalus (SDH) in patients with subarachnoid hemorrhage (SAH) and hydrocephalus. MATERIAL AND METHODS: This retrospective study was conducted from July 2018 to December 2022 and included 67 patients with SAH accompanied by acute hydrocephalus. Patients' demographic, clinical, and radiological data, such as age, sex, Glasgow Coma Scale scores, Hunt and Hess scale, Fischer grade, external ventricular drain (EVD) duration, complications, Ommaya reservoir placement, cerebrospinal fluid drainage, and outcomes, were obtained. Statistical analyses, including univariate analysis and stepwise logistic regression, revealed significant risk factors for shunt dependence. RESULTS: Of the 67 patients, 33 underwent microsurgical clipping and 34 received EVT. Spasmolysis reduced shunt dependency, whereas early EVD placement correlated with reduced shunt dependence (p=0.002). The Ommaya reservoir helped in the management of meningitis but was found to be associated with shunt dependency (p=0.04). Multiple logistic regression analysis revealed that perioperative infarct was a significant risk factor for shunt dependence (p=0.05). No significant difference in patient outcomes was observed between the two treatment groups. However, patients who received EVT had shorter intensive care unit and hospital stays. CONCLUSION: This study shows that managing clinical vasospasm with spasmolysis may reduce shunt dependency. Overall, both microsurgical clipping and EVT offer similar long-term outcomes and efficacy in preventing shunt dependence, but the latter has the advantage of shorter hospital stay. These findings provide crucial insights for clinical decision-making and patient care in SDH after SAH.


Asunto(s)
Aneurisma Roto , Procedimientos Endovasculares , Hidrocefalia , Hemorragia Subaracnoidea , Humanos , Femenino , Masculino , Hidrocefalia/cirugía , Hidrocefalia/etiología , Procedimientos Endovasculares/métodos , Persona de Mediana Edad , Estudios Retrospectivos , Aneurisma Roto/cirugía , Aneurisma Roto/complicaciones , Hemorragia Subaracnoidea/cirugía , Hemorragia Subaracnoidea/complicaciones , Anciano , Resultado del Tratamiento , Adulto , Derivaciones del Líquido Cefalorraquídeo , Aneurisma Intracraneal/cirugía , Aneurisma Intracraneal/complicaciones , Instrumentos Quirúrgicos , Microcirugia/métodos , Procedimientos Neuroquirúrgicos/métodos
19.
World Neurosurg ; 184: e743-e753, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38342171

RESUMEN

BACKGROUND: Papilledema's association with hydrocephalus (HCP)-linked larger vestibular schwannoma (VS) is established but cases lacking concurrent HCP require further investigation. METHODS: This retrospective comparative observational study, conducted from July 2018 to July 2023, examined 120 VS patients undergoing surgery. Patients were categorized into Group 1 (papilledema without HCP) and Group 2 (no papilledema or HCP), with comprehensive data analyzed. RESULTS: In this study, Group 1 (14 patients with papilledema) and Group 2 (106 patients without papilledema or HCP) were compared. Group 1 was younger (mean age 27.21 ± 11.73 years) than Group 2 (mean age 54.66 ± 11.44 years). Both groups had similar symptom durations and tumor detection times. Group 1 had increased vascularity (P = 0.001), elevated cisterna magna protein levels (P = 0.001), and a higher incidence of neurofibromatosis 2 (P = 0.003). They also experienced longer surgeries (P = 0.001) and more blood loss (P = 0.001), leading to extended postoperative complications. Group 2 showed improved postsurgery visual outcomes (P = 0.001), better Glasgow Outcome Scores (P = 0.001), enhanced facial nerve preservation (P = 0.002), and improved hearing on follow-up (P = 0.003). Logistic regression analysis highlighted prolonged surgery duration (P = 0.057) and papilledema (P = 0.0001) as significant factors influencing visual improvement. CONCLUSIONS: Patients with VS require preoperative fundoscopy evaluation due to potential visual loss and papilledema, even without HCP. Early treatment initiation enhances visual and hearing outcomes. Meticulous surgery is vital given the lesion's hypervascular nature and adherence to surrounding structures. Preoperative embolization may aid in preserving neurovascular structures. In developing countries with higher blindness rates, judicious noncontrast computed tomography brain evaluation is crucial for timely detection and treatment initiation of lesions like VS.


Asunto(s)
Hidrocefalia , Neuroma Acústico , Papiledema , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Neuroma Acústico/complicaciones , Neuroma Acústico/diagnóstico por imagen , Neuroma Acústico/cirugía , Papiledema/diagnóstico por imagen , Papiledema/etiología , Estudios Retrospectivos , Hidrocefalia/etiología , Hidrocefalia/cirugía , Hidrocefalia/diagnóstico , Ceguera , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Progresión de la Enfermedad , Resultado del Tratamiento
20.
Surg Neurol Int ; 15: 98, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38628510

RESUMEN

Background: Giant cavernous carotid artery aneurysms (>25 mm) are rare (3-5%), with some prone to spontaneous thrombosis (10-20% complete). We present a unique case of one of the largest aneurysms spontaneously thrombosing and calcifying. Case Description: A 57-year-old with persistent right-sided headaches had a substantial hyperdense mass in the right middle cranial fossa, eroding petrous bone. Magnetic resonance imaging and digital subtraction angiography revealed a giant cavernous segment fusiform aneurysm of the right internal carotid artery (ICA) with spontaneous thrombosis and distal ICA occlusion. Collateral circulation maintains the cerebral blood supply. Despite anatomical challenges, conservative management was chosen due to the patient's stability. Conclusion: This case highlights the complex interplay between thrombosed giant aneurysms and affected vessels, with unique features such as cross-flow, calcification, and bone erosion. We advocate conservative management for stable cases, supported by literature, emphasizing vigilant follow-up. This expands the spectrum of aneurysm presentations and encourages further research into their dynamics.

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