Correction to: Review of global neurosurgery education: Horizon of Neurosurgery in the Developing Countries.

[This corrects the article DOI: 10.1186/s41016-020-00194-1.].

Review of global neurosurgery education: Horizon of Neurosurgery in the Developing Countries.

Globally, the discipline of neurosurgery has evolved remarkably fast. Despite being one of the latest medical specialties, which appeared only around hundred years ago, it has witnessed innovations in the aspects of diagnostics methods, macro and micro surgical techniques, and treatment modalities. Unfortunately, this development is not evenly distributed between developed and developing countries. The same is the case with neurosurgical education and training, which developed from only traditional apprentice programs in the past to more structured, competence-based programs with various teaching methods being utilized, in recent times. A similar gap can be observed between developed and developing counties when it comes to neurosurgical education. Fortunately, most of the scholars working in this field do understand the coherent relationship between neurosurgical education and neurosurgical practice. In context to this understanding, a symposium was organized during the World Federation of Neurological Surgeons (WFNS) Special World Congress Beijing 2019. This symposium was the brain child of Prof. Yoko Kato-one of the eminent leaders in neurosurgery and an inspiration for female neurosurgeons. Invited speakers from different continents presented the stages of development of neurosurgical education in their respective countries. This paper summarizes the outcome of these presentations, with particular emphasis on and the challenges faced by developing countries in terms of neurosurgical education and strategies to cope with these challenges.

Obtaining accurate and calibrated coil models for transcranial magnetic stimulation using magnetic field measurements.

Currently, simulations of the induced currents in the brain produced by transcranial magnetic stimulation (TMS) are used to elucidate the regions reached by stimuli. However, models commonly found in the literature are too general and neglect imperfections in the windings. Aiming to predict the stimulation sites in patients requires precise modeling of the electric field (E-field), and a proper calibration to adequate to the empirical data of the particular coil employed. Furthermore, most fabricators do not provide precise information about the coil geometries, and even using X-ray images may lead to subjective interpretations. We measured the three components of the vector magnetic field induced by a TMS figure-8 coil with spatial resolutions of up to 1 mm. Starting from a computerized tomography-based coil model, we applied a multivariate optimization algorithm to automatically modify the original model and obtain one that optimally fits the measurements. Differences between models were assessed in a human brain mesh using the finite-elements method showing up to 6% variations in the E-field magnitude. Our calibrated model could increase the precision of the estimated E-field induced in the brain during TMS, enhance the accuracy of delivered stimulation during functional brain mapping, and improve dosimetry for repetitive TMS. Graphical Abstract Geometrical model of TMS coil based on TAC images is optimally deformed to match magnetic field measurements. The calibrated model's induced electric field in the brain differs from the original.

Progressive multifocal leukoencephalopathy presenting as IRIS in an AIDS patient. A case report and literature review.

Progressive multifocal leukoencephalopathy causes an infection of the central nervous system by JC virus (JCV), a polyomavirus that destroys oligodendrocytes and their myelin processes. Here, we describe a patient with AIDS who developed a progressive multifocal leucoencephalopathy with the clinical and neuroimaging characteristics of the immune inflammatory reconstitution syndrome. Unlike other opportunistic infections, this disease can present when CD4 T cell counts are higher than those associated with AIDS and also when patients are receiving combined antiretroviral therapy. Clinical suspicion of this form of the disease is based on clinical examination that shows focal neurological deficits associated with magnetic resonance images findings. The histopathological examination of brain biopsy smears and the identification of JCV in cerebrospinal fluid or brain tissue are definitive for the diagnosis.

Disseminated paracoccidioidomycosis with a single brainstem lesion. A case report and literature review.

Paracoccidioidomycosis is a systemic disease endemic to subtropical areas in Central and South America caused by a dimorphic fungus known as Paracoccidioides brasiliensis. Central nervous system involvement is a severe complication of the systemic disease, and has been found in approximately 13% of patients. This paper describes the case of a patient whose computed tomography scan and magnetic resonance imaging showed a single tumor-like lesion in the brainstem. Histopathological and mycological examinations of stereotactic biopsy smears showed the characteristic yeast cells that confirmed the diagnosis of neuroparacoccidioidomycosis.

Gliosarcoma: an unusual cause of cerebral mass lesion in a patient with AIDS. A case report and review of the literature.

Malignant glioma is the most common primary brain neoplasm. Generally, gliomas are not included in the differential diagnosis of enhancing lesions of the central nervous system in patients infected by the human immunodeficiency virus. We report a case of gliosarcoma in a patient with AIDS presenting as a single cerebral lesion. Stereotactic brain biopsy was obtained and definitive histopathological diagnosis of gliosarcoma was made. A decline in the incidence of opportunistic infections associated with highly active antiretroviral therapy suggest the importance of early stereotactic biopsy to confirm the diagnosis of these neoplasms.