Guilherme Lepski

University of São Paulo | USP · Department of Neurology

Traumatic spinal cord injury is a major cause of disability for which there are currently no fully effective treatments. Recent studies using epidural electrical stimulation have shown significant advances in motor rehabilitation, even when applied during chronic phases of the disease. The present study aimed to investigate the effectiveness of epi...

Background and Objectives: Cavernous malformations (CM) are vascular malformations with low blood flow. The removal of brainstem CMs (BS) is associated with high surgical morbidity, and there is no general consensus on when to treat deep-seated BS CMs. The aim of this study is to compare the surgical outcomes of a series of deep-seated BS CMs with...

Degenerative diseases and injuries that compromise hand movement reduce individual autonomy and tend to cause financial and psychological problems to their family nucleus. To mitigate these limitations, over the past decade, hand exoskeletons have been designed to rehabilitate or enhance impaired hand movements. Although promising, these devices st...

Simple Summary Among all intracranial tumors, 31.5% are malignant, and among those, glioblastomas account for 47%. Recently, our group reported the case of a patient with glioblastoma who underwent vaccination based on dendritic cells and experienced near-complete tumor remission. Here we report the results of a phase I/II prospective, non-controll...

En los últimos años se ha visto un creciente interés por el conocimiento relacionado con el cerebro y las neurociencias. Esto ha llevado a que se genere una importante cantidad de investigaciones y que el contexto propicie el surgimiento de creencias erróneas. Estudios realizados en varios países convergen en el hallazgo de que el conocimiento sob...

Recent years have seen a growing interest in brain and neuroscience-related knowledge, both among laypeople and those working in critical areas such as health and education. The last decades have also seen an explosion in mass-produced information, as well as the advent of the infamous fake news. In several countries, the search for (and almost par...

The field of neuroscience has seen significant growth and interest in recent decades. While neuroscience knowledge can benefit laypeople as well as professionals in many different areas, it may be particularly relevant for educators. With the right information, educators can apply neuroscience-based teaching strategies as well as protect themselves...

Immunotherapy has brought hope to the fight against glioblastoma, but its efficacy remains unclear. We present the case of CST, a 25-year-old female patient with a large right-hemisphere glioblastoma treated with a dendritic–tumor cell fusion vaccine. CST showed a near-complete tumor response, with a marked improvement in her functional status and...

INTRODUCTION Immunotherapy is gradually being established as a relevant adjuvant therapy against cancer. Cell vaccination is a promising strategy for the treatment of glioblastoma (GBM). CarT and dendritic cells (DC) have been associated with partial response therapy in recent publications. METHODS Clinical data were evaluated including overall su...

The field of Neuroscience has experienced a growing interest in recent decades, which has led to an exponential growth in the amount of related information made available online as well as the market for Neuroscience-related courses. While this type of knowledge can be greatly beneficial to people working in science, health and education, it can al...

The oncological treatment of intracranial tumors demands an experienced and multidisciplinary team able to manage vascular complications and perform reconstructive procedures when needed. Some brain tumors dislocate, enclose, and sometimes invade major arterial and venous structures of the brain, which if sacrificed may lead to unacceptable neurolo...

Objective Dorsal root ganglion stimulation (DRGS) is able to relieve chronic neuropathic pain. There seems evidence that DRGS might achieve this by gradually influencing pain pathways. We used laser evoked potentials (LEP) to verify our hypothesis that the recovery of the LEP may reflect DRGS induced changes within the nociceptive system. Methods...

Cerebellar symptoms remain orphan of treatment options despite being prevalent and incapacitating. Investigate whether dentate nucleus deep brain stimulation (DN DBS) is safe and leads to improvements in cerebellar symptoms when compared to sham stimulation. This randomized double-blind crossover pilot trial enrolled five patients with spinocerebel...

Background: The cerebellum has emerged as an attractive and promising target for neuromodulation in movement disorders due to its vast connection with important cortical and subcortical areas. Here, we describe a novel technique of deep brain stimulation (DBS) of the dentate nucleus (DN) aided by tractography. Methods: Since 2015, patients with...

The objective of this study was to calculate the risk of postsurgical hearing deterioration as a function of changes in the amplitude and latency of the most stable components (waves III and V) of the auditory evoked potential (AEP) during petroclival meningioma resection surgery. We retrospectively analyzed intraoperative AEP monitoring results an...

Objectives Several factors are commonly associated with the occurrence of post-operative infection after craniotomy. However, the risk factors associated with tumor surgery have been less intensively investigated. The aim of the present study was to analyze the risk factors for infection and categorize patients according to risk rate. Methods In t...

Background The current standard treatment for glioblastoma (GBM) is maximal safe surgical resection followed by radiation and chemotherapy. Unfortunately, the disease will invariably recur even with the best treatment. Although the literature suggests some advantages in reoperating patients harboring GBM, controversy remains. Here, we asked whether...

Neuropathic pain after spinal cord injury (SCI) is a complex condition that responds poorly to usual treatments. Cell transplantation represents a promising therapy; nevertheless, the ideal cell type in terms of neurogenic potential and effectiveness against pain remains largely controversial. Here, we evaluated the ability of fetal neural stem cel...

Objective: Large multicenter studies have shown that small intracranial aneurysms are associated with a minimal risk of bleeding. Nevertheless, other large series have shown that most ruptured aneurysms are, in fact, the smaller ones. In the present study, we questioned whether small aneurysms are indeed not dangerous. Methods: We enrolled 290 p...

Purpose/aim: Neuropathic pain following spinal cord injury (SCI) has a tremendous impact on patient’s quality of life, and frequently is the most limiting aspect of the disease. In view of the severity of this condition and the absence of effective treatments, the establishment of a reliable animal model that reproduces neuropathic pain after injur...

Objectives Dorsal root ganglion stimulation (DRGS) has been used successfully against localized neuropathic pain. Nevertheless, the effects of DRGS on pain processing, particularly at the cortical level, remain largely unknown. In this study, we investigated whether positive responses to DRGS treatment would alter patients’ laser‐evoked potentials...

Background: Dorsal root ganglion stimulation (DRGS) treats discrete, localized areas of neuropathic pain. But there are no long-term results available so far. Objectives: We studied the long-term outcome of DRGS used in the treatment of chronic neuropathic pain. Study design: A prospective, longitudinal single center investigation. Setting:...

Introdução: A amaurose transitória é uma complicação rarapós-cirurgia da coluna vertebral. Tem maior incidência emcirurgias que exigem decúbito ventral. A etiopatogenia é incerta, mas tem sido relacionada com isquemia do nervo óptico, oclusão da artéria central da retina (OACR) e lesão ocular externa. Objetivos: Relatar um caso de amaurose bilatera...

Objectives To review a surgical series of petroclival meningiomas and the factors considered in the choice of approach. Design Retrospective review. Setting The study was conducted in a university hospital in southern Brazil. Participants Twenty-two patients with petroclival meningioma originating from the upper two-thirds of the clivus medial to t...

Immunohistochemistry is routinely used in differential diagnosis of tumours of the central nervous system (CNS). The latest 2016 WHO 2016 revision now includes molecular data such as IDH mutation and 1p/19q codeletion thus restructuring glioma classification. Direct comparative information between commonly used immunohistochemical markers for glial...

Objective: Chronic neuropathic pain in the groin is a severe condition and difficult to treat. Dorsal root ganglion stimulation (DRGS) covers discrete painful areas precisely with its stimulation power in comparison to spinal cord stimulation (SCS). It was our hypothesis that DRGS provides a long-term relief of chronic groin pain over a period of...

Background The impact of prolonging temozolomide (TMZ) maintenance beyond six cycles in newly diagnosed glioblastoma (GBM) remains a topic of discussion. We investigated the effects of prolonged TMZ maintenance on progression-free survival (PFS) and overall survival (OS). Patients and Methods In this retrospective single-center cohort study, we in...

Surgical resection of petroclival meningiomas remains challenging due to their deep location and relationship to vital neurovascular structures. Although the natural history of these tumors involves a slow course, the incidence of cranial nerve deficits and the extent of tumor resection vary widely in the literature. Some reviews on this topic have...

Dystonia is characterized by sustained or intermittent muscle contractions leading to abnormal movements and impairment in daily activities. Stereotactic dentatotomy has been a treatment option in cases of spasticity or dystonia, especially in patients with cerebral palsy, but the long-term effect of dentatotomy in dystonia is still unknown. Here w...

Objective Chronic neuropathic pain is difficult to treat. Recently, a novel target for neuromodulation, the DRG, has been shown to be effective in managing neuropathic pain. However, the mechanisms underlying the impact of DRG stimulation are not well established. Therefore, we want to assess LEP’s for the quantification of the effects of DRG stimu...

Introduction: In the field of Glioma surgery, there has been an increasing interest in the use of assistive technologies to overcome the difficulty of preserving brain function while improving surgical radicality. In most reports, tumor localization has seldom been considered a variable and the role of intraoperative adjuncts is yet to be determin...

Hypoglossal canal meningiomas (HCMs) are extremely rare, and a consensus has yet to be reached regarding the most appropriate treatment approach for these types of tumors. Surgical procedures to the hypoglossal canal are often complex and lengthy, and are often associated with high rates of morbidity. Several approaches have been used to remove suc...

Background: The assessment of the functionality of intrathecal drug delivery (IDD) systems remains difficult and time-consuming. Catheter-related problems are still very common, and sometimes difficult to diagnose. Objectives: The aim of the present study is to investigate the accuracy of high-resolution three-dimensional computed tomography (CT...

Objectives: Foramen magnum meningiomas (FMMs) represent a technical challenge even for experienced neurosurgeons, because they grow in close contact with osteoarticular, nervous, and vascular structures that cannot be sacrificed or retracted during surgery. Our goal is to present our experience with 24 cases of surgically resected foramen magnum m...

Objectives: Foramen magnum meningiomas (FMMs) represent a technical challenge even for experienced neurosurgeons, because they grow in close contact with osteoarticular, nervous, and vascular structures that cannot be sacrificed or retracted during surgery. Our goal is to present our experience with 24 cases of surgically resected foramen magnum me...

Neste artigo de revisão, buscamos ressaltar alguns dos avanços mais recentes na pesquisa sobre células-tronco em neurologia. Além disso, buscamos demonstrar a direta associação entre seu funcionamento e mecanismos de replicação, diferenciação e maturação, além da terapêutica celular de algumas doenças neurológicas. Abordamos a provável associação e...

The cerebrocerebellum receives input from the cerebral cortex and projects to the motor and premotor cortices and the ventrolateral nucleus of the thalamus via the dentate nucleus (DN). Dentothalamocortical projections modulate the activity of the contralateral primary motor (M1) cortex and are involved in movement planning. Acute ischemic injury o...

Background: Abnormal upper arm-forearm muscle synergies after stroke are poorly understood. We investigated whether upper arm function primes paralyzed forearm muscles in chronic stroke patients after Brain-Machine Interface (BMI)-based rehabilitation. Shaping upper arm-forearm muscle synergies may support individualized motor rehabilitation strat...

Objectives A few recent studies have focused on epidural hematomas (EDHs) that are routine in emergency rooms. The study was to evaluate the latest situation of affected patients by encephalic trauma associated with EDH in our service. Methods Prospective study between September 1, 2003 and May 30, 2009. Data were computed regarding age, sex, traum...

Intermediate nerve neuralgia (INN) is an extremely rare craniofacial pain disorder mainly caused by neurovascular compression. We present the case of a 48-year-old female with a 20-month history of intractable paroxysmal INN on the right side. The patient described feeling paroxysmal pain in her auditory canal, pinna, deep in the jaw, and adjacent...

Subthalamic nucleus (STN) high-frequency stimulation (HFS) is a routine treatment in Parkinson's disease (PD), with confirmed long-term benefits. An alternative, but still experimental, treatment is cell replacement and restorative therapy based on transplanted dopaminergic neurons. The current experiment evaluated the potential synergy between neu...

Spasticity represents a common and very often incapacitating neurologic condition, for which a limited number of treatment options are available. Stereotactic ablation of the dentate cerebellar nuclei (dentatotomy) was widely used in the past with variable results. In the present study, we reviewed 12 consecutive cases operated on at the Midland Ce...

Stem cells represent a promising step for the future of regenerative medicine. As they are able to differentiate into any cell type, tissue or organ, these cells are great candidates for treatments against the worst diseases that defy doctors and researchers around the world. Stem cells can be divided into three main groups: (1) embryonic stem cell...

Background/Study Aims Percutaneous radiofrequency trigeminal rhizotomy (RTR) is a standardized treatment for trigeminal neuralgia, yet it has been associated with serious complications related to the cannulation of the foramen ovale. Some of these complications, such as carotid injury, are potentially lethal. Neuronavigation was recently proposed a...

Introduction Chordoid glioma is a rare low-grade brain tumor originating from the anterior wall of the third ventricle. Case presentation A 13-year-old female with progressive intermittent holocranial headaches and a diagnosis of chordoid glioma underwent tumor resection in our neuro-oncology unit. Discussion We review all 79 cases of chordoid gl...

Glossopharyngeal neuralgia (GPN) is an unusual cause of facial pain, corresponding to approximately 0.2-1.3%. Patients usually presents with facial pain associated with daily life activities (cough, swallow) and in severe cases with syncop. Epidemiology of the pathology demonstrates controversy about the predominance of the male, being consensus fr...

Several studies published to date about glioma surgery have addressed the validity of using novel technologies for intraoperative guidance and potentially improved outcomes. However, most of these reports are limited by questionable methods and/or by their retrospective nature. In this work, we performed a systematic review of the literature to add...

Unlabelled: Spinal cord injury (SCI) and amyotrophic laterals sclerosis (ALS) are devastating neurological conditions that affect individuals worldwide, significantly reducing quality of life, both for patients and their relatives. Objective: The present review aims to summarize the multiple restorative approaches being developed for spinal cord...

Unlabelled: Central nervous system (CNS) restoration is an important clinical challenge and stem cell transplantation has been considered a promising therapeutic option for many neurological diseases. Objective: The present review aims to briefly describe stem cell biology, as well as to outline the clinical application of stem cells in the trea...

Malignant brain tumors, including glioblastoma multiforme (GBM), are known for their high degree of invasiveness, aggressiveness, and lethality. These tumors are made up of heterogeneous cell populations and only a small part of these cells (known as cancer stem cells) is responsible for the initiation and recurrence of the tumor. The biology of ca...

The microsurgical reconstruction of the cauda equina nerve roots (MRCER) after traumatic injury is a highly controversial procedure with very few reports in the literature. We report on four patients who had a penetrating traumatic injury in the lumbosacral area and underwent primary MRCER at our institution during the last decade. All four patient...

The molecular mechanisms underlying the differentiation of neural progenitor cells (NPCs) remain poorly understood. In this study we investigated the role of Ca(2+) and cAMP (cyclic adenosine monophosphate) in the differentiation of NPCs extracted from the subventricular zone of E14.5 rat embryos. Patch clamp recordings revealed that increasing cAM...

Cell transplantation, as a therapeutic intervention for spinal cord injury (SCI), has been extensively studied by researchers in recent years. A number of different kinds of stem cells, neural progenitors, and glial cells have been tested in basic research, and most have been excluded from clinical studies because of a variety of reasons, including...

bstract Traumatic Brain Injury (TBI) is a devastating clinical condition that often causes permanent incapacity, especially in the younger population. The clinical relevant of TBI justifies the scientific interest in the pathophysiology of TBI, as well as in protective effects and development of treatment options. Stem cells have the ability to in...