Mapping angiography and transarterial technetium macroaggregated albumin particle simulation of recurrent atypical intracranial meningioma: feasibility for potential vascular brachytherapy

AbstractParticle simulation has been widely used in studying plasmas. The technique follows the motion of a large assembly of charged particles in their self-consistent electric and magnetic fields. Plasmons, collective oscillations of the free electrons in conducting media such as metals, are connected to plasmas by very similar physics, in particular, the notion of collective charge oscillations. In many cases of interest, plasmons are theoretically characterized by solving the classical Maxwell’s equations, where the electromagnetic responses can be described by bulk permittivity. That approach pays more attention to fields rather than motion of electrons. In this work, however, we apply the particle simulation method to model the kinetics of plasmons, by updating both particle position and momentum (Newton–Lorentz equation) and electromagnetic fields (Ampere and Faraday laws) that are connected by current. Particle simulation of plasmons can offer insights and information that supplement those gained by traditional experimental and theoretical approaches. Specifically, we present two case studies to show its capabilities of modeling single-electron excitation of plasmons, tracing instantaneous movements of electrons to elucidate the physical dynamics of plasmons, and revealing electron spill-out effects of ultrasmall nanoparticles approaching the quantum limit. These preliminary demonstrations open the door to realistic particle simulations of plasmons.

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Meningiomas and cyproterone acetate: a retrospective, monocentric cohort of 388 patients treated by surgery or radiotherapy for intracranial meningioma

Journal of Neuro-Oncology ◽

10.1007/s11060-020-03683-6 ◽

2021 ◽

Author(s):

Edouard Samarut ◽

Alexandre Lugat ◽

Aymeric Amelot ◽

Emeric Scharbarg ◽

Samy Hadjadj ◽

...

Keyword(s):

Cyproterone Acetate ◽

Intracranial Meningioma

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Particle simulation of streamer discharges on surface of DC transmission line in presence of raindrops

Journal of Applied Physics ◽

10.1063/5.0044294 ◽

2021 ◽

Vol 129 (18) ◽

pp. 183306

Author(s):

Xin-chun Zhang ◽

Feng Wang ◽

Nan-nan Liu ◽

An-qi Li ◽

Wei-li Fan

Keyword(s):

Transmission Line ◽

Particle Simulation ◽

Streamer Discharges

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Evaluation of surgical outcome of giant intracranial meningiomas

Egyptian Journal of Neurosurgery ◽

10.1186/s41984-020-00092-9 ◽

2020 ◽

Vol 35 (1) ◽

Author(s):

Ramy Teama ◽

Mohamed Adawy ◽

Mohamed Emara

Keyword(s):

Surgical Outcome ◽

Intraoperative Complications ◽

Intracranial Meningioma ◽

Surgical Removal ◽

Study Group ◽

Main Body ◽

Total Removal ◽

Large Size ◽

Intracranial Meningiomas

Abstract Background The surgery of giant intracranial meningiomas (GIM) is difficult due to its large size, prominent vascularity, including and limiting visualization of various neurovascular structures, and severe cerebral edema. In this study, we will evaluate the surgical outcome of giant meningiomas according to our experience at our hospital in management of giant intracranial meningioma. Main body A retrospective analysis of 48 patients with histologically proven meningioma (≥ 6-cm diameter) who underwent surgical treatment at Benha University hospitals over a period of 5 years (June 2014/June 2019) is presented. Details regarding clinical presentation, imaging findings, surgical results and complications, and follow-up status were collected. The study group was composed of 41 females and 7 males. The age of the study group ranged from 38 to 69 years with an average of 49 years. The mean follow-up period was 36 months. Different approaches were used according to tumor location with the aim of gross total removal. Gross total removal was achieved in 90% of cases (43 cases). There were 2 cases with intraoperative complications not related to surgery. Recurrence was present in 4 cases. Mortality in this series was 4% (2 cases) with no reported intraoperative mortality. Conclusion Management of giant intracranial meningioma is a relatively common practice in neurosurgical centers in developing countries with the aim of radical total surgical removal being the first and most optimum option. Large size makes surgery difficult, but young age, meticulous surgical techniques, proper localization, trying to minimize operative time, and Simpson grade are of special value. Interdisciplinary cooperation is essential to avoid the common complications like pulmonary embolism (PE), postoperative hematoma in tumor bed that leads to bad surgical outcome.

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Image-Guided Multisession Radiosurgery of Skull Base Meningiomas

Cancers ◽

10.3390/cancers12123569 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3569

Author(s):

Alfredo Conti ◽

Antonio Pontoriero ◽

Giuseppe Iatì ◽

Salvatore M. Cardali ◽

Anna Brogna ◽

...

Keyword(s):

Skull Base ◽

Stereotactic Radiosurgery ◽

Cranial Nerves ◽

Progression Free Survival ◽

Motor Deficits ◽

Intracranial Meningioma ◽

Treatment Schedule ◽

Fractionated Radiotherapy ◽

Patient Reported ◽

Skull Base Meningiomas

Background: The efficacy of single-session stereotactic radiosurgery (sSRS) for the treatment of intracranial meningioma is widely recognized. However, sSRS is not always feasible in cases of large tumors and those lying close to critically radiation-sensitive structures. When surgery is not recommended, multi-session stereotactic radiosurgery (mSRS) can be applied. Even so, the efficacy and best treatment schedule of mSRS are not yet established. The aim of this study is to validate the role of mSRS in the treatment of skull base meningiomas. Methods: A retrospective analysis of patients with skull base meningiomas treated with mSRS (two to five fractions) at the University of Messina, Italy, from 2008 to 2018, was conducted. Results: 156 patients met the inclusion criteria. The median follow-up period was 36.2 ± 29.3 months. Progression-free survival at 2-, 5-, and 10- years was 95%, 90%, and 80.8%, respectively. There were no new visual or motor deficits, nor cranial nerves impairments, excluding trigeminal neuralgia, which was reported by 5.7% of patients. One patient reported carotid occlusion and one developed brain edema. Conclusion: Multisession radiosurgery is an effective approach for skull base meningiomas. The long-term control is comparable to that obtained with conventionally-fractionated radiotherapy, while the toxicity rate is very limited.

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