Roberto S. Martins - Academia.edu (original) (raw)

Papers by Roberto S. Martins

Research paper thumbnail of Fibrolipomatous hamartoma of the median nerve: An unusual cause of carpal tunnel syndrome

Carpal tunnel release must be preceded by complete investigation to avoid misdiagnosis and surgic... more Carpal tunnel release must be preceded by complete investigation to avoid misdiagnosis and surgical complications

Research paper thumbnail of Avaliação dos efeitos da eliminação da tensão através de ancoramento epineural: estudo experimental comparando resultados eletrofisiológicos e histomorfométricos após diferentes técnicas de reparo no nervo

Epineural stitches are a means to avoid tension in a nerve suture. We evaluate this technique, re... more Epineural stitches are a means to avoid tension in a nerve suture. We evaluate this technique, relative to interposed grafts and simple neurorraphy, in a rat model. Method: Twenty rats were allocated to four groups. For Group 1, sectioning of the sciatic nerve was performed, a segment 4 mm long discarded, and epineural suture with distal anchoring stitches were placed resulting in slight tension neurorraphy. For Group 2, a simple neurorraphy was performed. For Group 3, a 4 mm long graft was employed and Group 4 served as control. Ninety days after, reoperation, latency of motor action potentials recording and axonal counts were performed. Inter-group comparison was done by means of ANOVA and the non-parametric Kruskal-Wallis test. Results: The mean motor latency for the simple suture (2.27±0.77 ms) was lower than for the other two surgical groups, but lower than among controls (1.69±0.56 ms). Similar values were founding in both group 1 (2.66±0.71 ms) and group 3 (2.64±0.6 ms). When...

Research paper thumbnail of Diagnostic accuracy of imaging studies for diagnosing root avulsions in post-traumatic upper brachial plexus traction injuries in adults

Acta Neurochirurgica, 2020

Background There is no consensus about which type of imaging study, computed tomography myelograp... more Background There is no consensus about which type of imaging study, computed tomography myelography (CTM) or magnetic resonance imaging (MRI), provides better information concerning root avulsion in adult brachial plexus injuries. Methods Patients with upper brachial plexus traumatic injuries underwent both CTM and MRI and surgical exploration. The imaging studies were analyzed by two independent radiologists and the data were compared with the intraoperative findings. The statistical analysis was based on dichotomous classification of the nerve roots (normal or altered). The interobserver agreement was assessed using Cohen's Kappa. The accuracy of CTM and MRI in comparison with the intraoperative findings was evaluated using the same methodology. Results Fifty-two adult patients were included. CTM tended to yield slightly higher percentages of alterations than MRI The interobserver agreement was better on CTM than on MRI for all nerve roots: C5, 0.9960 (strong) vs. 0.145 (poor); C6, 0.970 (strong) vs. 0.788 (substantial); C7, 0.969 (strong) vs. 0.848 (strong). The accuracy regarding the intraoperative findings was also higher on CTM (moderate, kappa 0.40-0.59) than on MRI (minimal, kappa 0.20-0.39) for all nerve roots. Accordingly, the overall percentage concordance (both normal or both altered) was superior in the CTM evaluation (approx. 70-75% vs. 60-65%). CTM was superior for both sensitivity and specificity at all nerve roots. Conclusion CTM had greater interobserver agreement and higher diagnostic accuracy than MRI in adult patients with root avulsions due to brachial plexus injury. Keywords Brachial plexus injuries. Brachial plexus imaging studies. Computed tomography pyelography. Magnetic resonance imaging. Cervical root Abbreviations CTM Computed tomography myelography MRI Magnetic resonance imaging This article is part of the Topical Collection on Peripheral Nerves

Research paper thumbnail of Cisto sinovial intraneural do nervo fibular: relato de caso

Arquivos de Neuro-Psiquiatria, 1997

Os autores apresentam um caso de um cisto sinovial intraneural ocorrendo no nervo fibular comum. ... more Os autores apresentam um caso de um cisto sinovial intraneural ocorrendo no nervo fibular comum. O paciente apresentou-se com quadro de dor e dificuldade para a flexão dorsal e eversão do pé sendo submetido a exploração cirúrgica com exérese do cisto. Neste estudo são discutidos a patogênese, manifestações clínicas e tratamento desta rara lesão.

Research paper thumbnail of Mecanismos básicos da regeneração de nervos: Artigo de revisão

Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery, 2005

ResumoUm grande número de pacientes portadores de lesões de nervos é tratado por meio de interven... more ResumoUm grande número de pacientes portadores de lesões de nervos é tratado por meio de intervenção cirúrgica. Embora nos últimos anos evoluções constantes tenham sido obtidas na elucidação dos mecanismos básicos da regeneração de nervos, esse progresso ainda não foi incorporado de forma eficaz às situações clínicas.Neste estudo apresentamos uma revisão dos mecanismos básicos da regeneração de nervos. O conhecimento desses mecanismos é o primeiro passo para que terapêuticas adjuvantes sejam desenvolvidas e adicionadas rotineiramente à cirurgia no tratamento das lesões traumáticas de nervos.

Research paper thumbnail of Uso da nanotecnologia no reparo das lesões traumáticas de nervos

Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery, 2007

ResumoA nanotecnologia tem permitido avanços revolucionários nos últimos anos em diversas áreas d... more ResumoA nanotecnologia tem permitido avanços revolucionários nos últimos anos em diversas áreas da Ciência, incluindo a medicina, onde o impacto de novas aquisições se faz presente também na neurocirurgia. Trabalhos experimentais têm demonstrado diversas possibilidades do uso de artefatos obtidos a partir da nanotecnologia no tratamento das lesões traumáticas de nervos periféricos. Isto inclui desde a construção de dispositivos semi-sintéticos que substituem a estrutura de um nervo até a manipulação direta dos axônios. O objetivo deste estudo é apresentar ao neurocirurgião uma revisão sobre as principais técnicas de manufatura de nanomateriais e suas aplicações atuais e futuras no manejo das patologias traumáticas dos nervos periféricos.

Research paper thumbnail of Tumor dermóide intramedular associado a diastematomielia: relato de caso

Arquivos de Neuro-Psiquiatria, 2000

A associação de tumor dermóide intramedular e diastematomielia é rara, descrita anteriormente em ... more A associação de tumor dermóide intramedular e diastematomielia é rara, descrita anteriormente em 8 casos. Descrevemos novo caso, de um adulto portador desta associação que apresentou paraparesia crural progressiva e síndrome sensitiva nos membros inferiores, além de cifoescoliose tóraco-lombar. A exploração cirúrgica confirmou a ocorrência de um tumor dermóide intramedular além da diastematomielia identificados na ressonância magnética. Discutemos aspectos fisiopatológicos e clínicos e as características radiológicas destas patologias destacando a importância do diagnóstico precoce.

Research paper thumbnail of Classificação das fraturas tóraco-lombares baseada em investigação por imagem: avaliação de 33 casos

Arquivos de Neuro-Psiquiatria, 2006

As fraturas das regiões torácica e lombar da coluna vertebral constituem amplo espectro de difere... more As fraturas das regiões torácica e lombar da coluna vertebral constituem amplo espectro de diferentes tipos de lesões resultantes de mecanismos fisiopatológicos distintos. A fim de se reduzir as controvérsias existentes a respeito da conduta destas lesões é necessária a utilização de uma classificação que permita a sua correta caracterização. Neste estudo avaliamos retrospectivamente 33 pacientes portadores de fraturas tóraco-lombares com o objetivo de categorizar e avaliar os fatores relacionados a esta patologia. O mecanismo de trauma mais freqüente foi queda de altura, presente em 24 casos. Na maioria dos pacientes (57,6%) as fraturas localizaram-se na transição tóraco-lombar (T12-L1) e o quadro neurológico mais freqüente foi o déficit sensitivo-motor completo abaixo da lesão, em 45,45% dos casos. A apresentação neurológica foi mais grave nos pacientes com lesões torácicas em relação às lesões lombares (teste de Fischer, p=0,039). Uma correlação positiva foi observada entre a sev...

Research paper thumbnail of Infecções de derivações liquóricas em crianças: revisão de 100 infecções em 87 crianças

Arquivos de Neuro-Psiquiatria, 1997

Estudo retrospectivo analisando quadro clínico e resultados terapêuticos de 100 episódios de infe... more Estudo retrospectivo analisando quadro clínico e resultados terapêuticos de 100 episódios de infecções em 87 crianças submetidas a derivações liquóricas no período de 1982 a 1995.O quadro clínico mais frequente foi aquele secundário ao processo inflamatório e os agentes etiológicos mais comuns foram os estafilococos. A infecção ocasionada por agente Gram negativo mostrou maior gravidade e esteve mais frequentemente relacionada a falha terapêutica. As estratégias de tratamento incluíram desde o uso de antibióticos sistêmicos de forma isolada até a retirada do sistema de derivação e a utilização de antibióticos sistêmicos e intratecais. Os melhores resultados terapêuticos foram obtidos com: retirada da derivação e sua substituição por derivação ventricular externa associada a antibióticoterapia sistêmica. Em nossa experiência, essa conduta deve ser adotada como rotina para o tratamento desta grave complicação.

Research paper thumbnail of Surgical treatment of adult traumatic brachial plexus injuries: an overview

Arquivos de Neuro-Psiquiatria, 2011

Traumatic injuries to the brachial plexus in adults are severely debilitating. They generally aff... more Traumatic injuries to the brachial plexus in adults are severely debilitating. They generally affect young individuals. A thorough understanding of the anatomy, clinical evaluation, imaging and electrodiagnostic assessments, treatment options and proper timing of surgical interventions will enable nerve surgeons to offer optimal care to patients. Advances in microsurgical technique have improved the outcome for many of these patients. The treatment options offer patients with brachial plexus injuries the possibility of achieving elbow flexion, shoulder stability with limited abduction and the hope of limited but potentially useful hand function.

Research paper thumbnail of Correlation between parameters of electrophysiological, histomorphometric and sciatic functional index evaluations after rat sciatic nerve repair

Arquivos de Neuro-Psiquiatria, 2006

The rat sciatic nerve is a well-established model for the study of recovery from peripheral nerve... more The rat sciatic nerve is a well-established model for the study of recovery from peripheral nerve injuries. Traditional methods of assessing nerve regeneration after nerve injury and repair, such as electrophysiology and histomorphometry, despite widely used in neural regeneration experiments, do not necessarily correlate with return of motor and sensory functions. The aim of this experimental study is to investigate the possible correlation between several parameters of peripheral nerve regeneration after repair of sectioned sciatic nerve in Wistar rat. A two-stage approach was used to obtain 17 parameters after electrophysiological, morphometric and sciatic functional index evaluations. Pearson's correlation analysis was performed between these results. Only two positives correlations between different classes of peripheral nerve assessments were noted, between sciatic functional index and proximal nerve fiber diameter (r=0.56, p<0.01) and between sciatic functional index a...

Research paper thumbnail of Electrophysiologic assessment of regeneration in rat sciatic nerve repair using suture, fibrin glue or a combination of both techniques

Arquivos de Neuro-Psiquiatria, 2005

We evaluated the repair of seccioned rat sciatic nerve by the comparison of electrophysiologic pa... more We evaluated the repair of seccioned rat sciatic nerve by the comparison of electrophysiologic parameters. The repair was effected with suture (group A), fibrin glue (group B) or a combination of both techniques (group C). The amplitude, latency and conduction velocity of the motor and nerve action potentials were assessed before the nerve section and at reoperation after 24 weeks. There was no difference between the groups when the nerve action potential was evaluated. Rats of group B presented better results than those of group A (p<0.05) when latency and the nerve conduction velocity assessed at the reoperation, and the ratio between the conduction velocity at the reoperation and before the nerve section in the motor action potential evaluation were measured. Animals of group C presented better results than those of group A when the ratio between the conduction velocity of motor action potential at the reoperation and before the nerve division was considered (p<0.05). No di...

Research paper thumbnail of Clinical Results of Transferring a Motor Branch of the Tibial Nerve to the Deep Peroneal Nerve for Treatment of Foot Drop

Neurosurgery, 2013

BACKGROUND: Foot drop is a very debilitating condition affecting patients' daily activities, ... more BACKGROUND: Foot drop is a very debilitating condition affecting patients' daily activities, and its treatment has been a challenge for neurosurgeons. Grafting the peroneal or sciatic nerve usually results in poor outcomes. Our previous anatomic study demonstrated the feasibility of transferring a motor branch of the tibial nerve to the deep peroneal nerve at the level of the popliteal fossa. OBJECTIVE: To demonstrate the outcomes obtained after the transfer of a branch of the tibial nerve to the peroneal nerve for recovery of foot drop. METHODS: A retrospective review of 13 patients with foot drop caused by injuries to a lumbar root or the sciatic or peroneal nerve, who underwent a transfer of the nerve of the soleus muscle to the deep peroneal nerve. The results were evaluated using the British Medical Research Council grading system. RESULTS: Three patients were lost to follow-up. Of the remaining 10 patients, the outcomes were considered good (Medical Research Council grade ...

Research paper thumbnail of Abstract Article

Effects of eliminating tension by means of epineural stitches A comparative electrophysiological ... more Effects of eliminating tension by means of epineural stitches A comparative electrophysiological and histomorphometrical study using different suture techniques in an animal model

Research paper thumbnail of Cervical Schwannoma of the Vagus Nerve: Two Illustrative Cases

Background: Cervical schwannoma is a rare and benign tumor exclusively developed from the cell of... more Background: Cervical schwannoma is a rare and benign tumor exclusively developed from the cell of Schwann that rarely involves the vagus nerve. Methods: We reported two illustrative cases and a brief literature review. Both patients presented with a history of painless palpable mass in the cervical region. Results: In both cases the lesions were diagnosed by means of imaging studies and were totally resected. Surgical findings and histopathology confirmed the diagnosis of vagus nerve schwannoma. There was no recurrence at five years of follow-up. In one case there was dysphonia that solved within six months after the surgery. Conclusion: Vagus nerve schwannomas are rare benign tumors. The enucleation technique is used to obtain the most functional preservation and complete excision without permanent deficit is possible even with the occurrence of large lesions.

Research paper thumbnail of Masseteric-Facial Anastomosis: A Report of Three Cases

Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery, 2021

Intoduction The pathways of the facial nerve are variable, and knowledge of that is essential. Th... more Intoduction The pathways of the facial nerve are variable, and knowledge of that is essential. The worst impact caused by facial paralysis is related to quality of life, especially regarding the self-esteem and social acceptance on the part of the patients, leading to social isolation and disruption on their mental health. Case Report A 33-year-old female patient, with a stage-T3 acoustic neurinoma, presented with a moderate dysfunction (grades II to III) according to the House-Brackmann (HB) Facial Nerve Grading System. A 43-year-old male patient, with a stage-T4B trigeminal schwannoma, underwent a resective surgery and presented grade-VI dysfunction according to the HB scale. And a female patient with a stage-T4A acoustic neurinoma presented grade-IV dysfunction according to the HB scale. Discussion We performed a literature review of papers related to surgeries for masseteric-facial nerve anastomosis and compiled the results in table; then, we compared these data with those obtai...

Research paper thumbnail of The nerve to the levator scapulae muscle as donor in brachial plexus surgery: an anatomical study and case series

Journal of Neurosurgery, 2021

OBJECTIVENerve transfers are commonly used in treating complete injuries of the brachial plexus, ... more OBJECTIVENerve transfers are commonly used in treating complete injuries of the brachial plexus, but donor nerves are limited and preferentially directed toward the recovery of elbow flexion and shoulder abduction. The aims of this study were to characterize the anatomical parameters for identifying the nerve to the levator scapulae muscle (LSN) in brachial plexus surgery, to evaluate the feasibility of transferring this branch to the suprascapular nerve (SSN) or lateral pectoral nerve (LPN), and to present the results from a surgical series.METHODSSupra- and infraclavicular exposure of the brachial plexus was performed on 20 fresh human cadavers in order to measure different anatomical parameters for identification of the LSN. Next, an anatomical and histomorphometric evaluation of the feasibility of transferring this branch to the SSN and LPN was made. Lastly, the effectiveness of the LSN-LPN transfer was evaluated among 10 patients by quantifying their arm adduction strength.RESU...

Research paper thumbnail of Treatment of radiation-induced brachial plexopathy with omentoplasty

Autopsy and Case Reports, 2020

An understanding of the climate conditions governing spatial variation in the reproductive perfor... more An understanding of the climate conditions governing spatial variation in the reproductive performance of plants can provide important information about the factors characterizing plant community structure, especially in the context of climate change. This study focuses on the effect of climate on the sexual reproductive output of Dactylis glomerata L., a perennial grass species widely distributed throughout temperate regions. An indirect space-for-time substitution procedure was used. Sixty mountain populations of the same target species were surveyed along an elevation gradient, and then, a relevant climate model was used to infer a potential response to climate change over time. Within each population, information on the number of stems, seed number and seed mass were collected. Resource investment in reproduction (RIR) was quantified as seed number × seed mass. A clear variation was found in the reproductive performance of D. glomerata along the elevational gradient: RIR improved with increasing temperature. The best model included only one term: the maximum temperature of the warmest month. This study demonstrates that mountain ecosystems offer particularly good opportunities to study climate effects over relatively short distances and suggests that warming will enhance D. glomerata reproductive output throughout its elevational range. Furthermore, it can be hypothesized that a potential migration of D. glomerata toward higher altitudes may occur in response to accelerated climate change.

Research paper thumbnail of Pain Threshold in Migraine and Tension-Type Headache by Pressure Algometry in Craniocervical Muscles and Peripheral Nerves in Both Genders

Journal of Neurology & Stroke, 2017

Patients and Methods Study design and Patients This was a prospective study with comparison of gr... more Patients and Methods Study design and Patients This was a prospective study with comparison of groups. The study population comprised a non-random and convenience sampling, consisting of the first 20 control patients, 25 migraine patients and 20 tension-type headache (TTH) patients (comparison group). Inclusion criteria Patients aged between 20 and 50 years, no complaint of headache (control), with migraine or tensional-type headache, according to the diagnostic criteria of International Classification of Headache Disorders (ICHD)-2 [7] and absence of abortive medication for at least 5 days were included in the study. Exclusion criteria Patients with psychiatric disorders, skin diseases (psoriasis, herpes zoster and leprosy that interfere with the perception of pain), patients with any type of secondary headache, abnormal neurological or neuroimaging examination, congenital

Research paper thumbnail of Estudo prospectivo comparando a utilização de fascículo do nervo ulnar isolado ou em associação com fascículo do nervo mediano para a restituição da flexão do antebraço nas lesões parciais pós-traumáticas do plexo braquial

Estudo prospectivo comparando a utilização de fascículo do nervo ulnar isolado ou em associação c... more Estudo prospectivo comparando a utilização de fascículo do nervo ulnar isolado ou em associação com fascículo do nervo mediano para a restituição da flexão do antebraço nas lesões parciais póstraumáticas do plexo braquial

Research paper thumbnail of Fibrolipomatous hamartoma of the median nerve: An unusual cause of carpal tunnel syndrome

Carpal tunnel release must be preceded by complete investigation to avoid misdiagnosis and surgic... more Carpal tunnel release must be preceded by complete investigation to avoid misdiagnosis and surgical complications

Research paper thumbnail of Avaliação dos efeitos da eliminação da tensão através de ancoramento epineural: estudo experimental comparando resultados eletrofisiológicos e histomorfométricos após diferentes técnicas de reparo no nervo

Epineural stitches are a means to avoid tension in a nerve suture. We evaluate this technique, re... more Epineural stitches are a means to avoid tension in a nerve suture. We evaluate this technique, relative to interposed grafts and simple neurorraphy, in a rat model. Method: Twenty rats were allocated to four groups. For Group 1, sectioning of the sciatic nerve was performed, a segment 4 mm long discarded, and epineural suture with distal anchoring stitches were placed resulting in slight tension neurorraphy. For Group 2, a simple neurorraphy was performed. For Group 3, a 4 mm long graft was employed and Group 4 served as control. Ninety days after, reoperation, latency of motor action potentials recording and axonal counts were performed. Inter-group comparison was done by means of ANOVA and the non-parametric Kruskal-Wallis test. Results: The mean motor latency for the simple suture (2.27±0.77 ms) was lower than for the other two surgical groups, but lower than among controls (1.69±0.56 ms). Similar values were founding in both group 1 (2.66±0.71 ms) and group 3 (2.64±0.6 ms). When...

Research paper thumbnail of Diagnostic accuracy of imaging studies for diagnosing root avulsions in post-traumatic upper brachial plexus traction injuries in adults

Acta Neurochirurgica, 2020

Background There is no consensus about which type of imaging study, computed tomography myelograp... more Background There is no consensus about which type of imaging study, computed tomography myelography (CTM) or magnetic resonance imaging (MRI), provides better information concerning root avulsion in adult brachial plexus injuries. Methods Patients with upper brachial plexus traumatic injuries underwent both CTM and MRI and surgical exploration. The imaging studies were analyzed by two independent radiologists and the data were compared with the intraoperative findings. The statistical analysis was based on dichotomous classification of the nerve roots (normal or altered). The interobserver agreement was assessed using Cohen's Kappa. The accuracy of CTM and MRI in comparison with the intraoperative findings was evaluated using the same methodology. Results Fifty-two adult patients were included. CTM tended to yield slightly higher percentages of alterations than MRI The interobserver agreement was better on CTM than on MRI for all nerve roots: C5, 0.9960 (strong) vs. 0.145 (poor); C6, 0.970 (strong) vs. 0.788 (substantial); C7, 0.969 (strong) vs. 0.848 (strong). The accuracy regarding the intraoperative findings was also higher on CTM (moderate, kappa 0.40-0.59) than on MRI (minimal, kappa 0.20-0.39) for all nerve roots. Accordingly, the overall percentage concordance (both normal or both altered) was superior in the CTM evaluation (approx. 70-75% vs. 60-65%). CTM was superior for both sensitivity and specificity at all nerve roots. Conclusion CTM had greater interobserver agreement and higher diagnostic accuracy than MRI in adult patients with root avulsions due to brachial plexus injury. Keywords Brachial plexus injuries. Brachial plexus imaging studies. Computed tomography pyelography. Magnetic resonance imaging. Cervical root Abbreviations CTM Computed tomography myelography MRI Magnetic resonance imaging This article is part of the Topical Collection on Peripheral Nerves

Research paper thumbnail of Cisto sinovial intraneural do nervo fibular: relato de caso

Arquivos de Neuro-Psiquiatria, 1997

Os autores apresentam um caso de um cisto sinovial intraneural ocorrendo no nervo fibular comum. ... more Os autores apresentam um caso de um cisto sinovial intraneural ocorrendo no nervo fibular comum. O paciente apresentou-se com quadro de dor e dificuldade para a flexão dorsal e eversão do pé sendo submetido a exploração cirúrgica com exérese do cisto. Neste estudo são discutidos a patogênese, manifestações clínicas e tratamento desta rara lesão.

Research paper thumbnail of Mecanismos básicos da regeneração de nervos: Artigo de revisão

Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery, 2005

ResumoUm grande número de pacientes portadores de lesões de nervos é tratado por meio de interven... more ResumoUm grande número de pacientes portadores de lesões de nervos é tratado por meio de intervenção cirúrgica. Embora nos últimos anos evoluções constantes tenham sido obtidas na elucidação dos mecanismos básicos da regeneração de nervos, esse progresso ainda não foi incorporado de forma eficaz às situações clínicas.Neste estudo apresentamos uma revisão dos mecanismos básicos da regeneração de nervos. O conhecimento desses mecanismos é o primeiro passo para que terapêuticas adjuvantes sejam desenvolvidas e adicionadas rotineiramente à cirurgia no tratamento das lesões traumáticas de nervos.

Research paper thumbnail of Uso da nanotecnologia no reparo das lesões traumáticas de nervos

Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery, 2007

ResumoA nanotecnologia tem permitido avanços revolucionários nos últimos anos em diversas áreas d... more ResumoA nanotecnologia tem permitido avanços revolucionários nos últimos anos em diversas áreas da Ciência, incluindo a medicina, onde o impacto de novas aquisições se faz presente também na neurocirurgia. Trabalhos experimentais têm demonstrado diversas possibilidades do uso de artefatos obtidos a partir da nanotecnologia no tratamento das lesões traumáticas de nervos periféricos. Isto inclui desde a construção de dispositivos semi-sintéticos que substituem a estrutura de um nervo até a manipulação direta dos axônios. O objetivo deste estudo é apresentar ao neurocirurgião uma revisão sobre as principais técnicas de manufatura de nanomateriais e suas aplicações atuais e futuras no manejo das patologias traumáticas dos nervos periféricos.

Research paper thumbnail of Tumor dermóide intramedular associado a diastematomielia: relato de caso

Arquivos de Neuro-Psiquiatria, 2000

A associação de tumor dermóide intramedular e diastematomielia é rara, descrita anteriormente em ... more A associação de tumor dermóide intramedular e diastematomielia é rara, descrita anteriormente em 8 casos. Descrevemos novo caso, de um adulto portador desta associação que apresentou paraparesia crural progressiva e síndrome sensitiva nos membros inferiores, além de cifoescoliose tóraco-lombar. A exploração cirúrgica confirmou a ocorrência de um tumor dermóide intramedular além da diastematomielia identificados na ressonância magnética. Discutemos aspectos fisiopatológicos e clínicos e as características radiológicas destas patologias destacando a importância do diagnóstico precoce.

Research paper thumbnail of Classificação das fraturas tóraco-lombares baseada em investigação por imagem: avaliação de 33 casos

Arquivos de Neuro-Psiquiatria, 2006

As fraturas das regiões torácica e lombar da coluna vertebral constituem amplo espectro de difere... more As fraturas das regiões torácica e lombar da coluna vertebral constituem amplo espectro de diferentes tipos de lesões resultantes de mecanismos fisiopatológicos distintos. A fim de se reduzir as controvérsias existentes a respeito da conduta destas lesões é necessária a utilização de uma classificação que permita a sua correta caracterização. Neste estudo avaliamos retrospectivamente 33 pacientes portadores de fraturas tóraco-lombares com o objetivo de categorizar e avaliar os fatores relacionados a esta patologia. O mecanismo de trauma mais freqüente foi queda de altura, presente em 24 casos. Na maioria dos pacientes (57,6%) as fraturas localizaram-se na transição tóraco-lombar (T12-L1) e o quadro neurológico mais freqüente foi o déficit sensitivo-motor completo abaixo da lesão, em 45,45% dos casos. A apresentação neurológica foi mais grave nos pacientes com lesões torácicas em relação às lesões lombares (teste de Fischer, p=0,039). Uma correlação positiva foi observada entre a sev...

Research paper thumbnail of Infecções de derivações liquóricas em crianças: revisão de 100 infecções em 87 crianças

Arquivos de Neuro-Psiquiatria, 1997

Estudo retrospectivo analisando quadro clínico e resultados terapêuticos de 100 episódios de infe... more Estudo retrospectivo analisando quadro clínico e resultados terapêuticos de 100 episódios de infecções em 87 crianças submetidas a derivações liquóricas no período de 1982 a 1995.O quadro clínico mais frequente foi aquele secundário ao processo inflamatório e os agentes etiológicos mais comuns foram os estafilococos. A infecção ocasionada por agente Gram negativo mostrou maior gravidade e esteve mais frequentemente relacionada a falha terapêutica. As estratégias de tratamento incluíram desde o uso de antibióticos sistêmicos de forma isolada até a retirada do sistema de derivação e a utilização de antibióticos sistêmicos e intratecais. Os melhores resultados terapêuticos foram obtidos com: retirada da derivação e sua substituição por derivação ventricular externa associada a antibióticoterapia sistêmica. Em nossa experiência, essa conduta deve ser adotada como rotina para o tratamento desta grave complicação.

Research paper thumbnail of Surgical treatment of adult traumatic brachial plexus injuries: an overview

Arquivos de Neuro-Psiquiatria, 2011

Traumatic injuries to the brachial plexus in adults are severely debilitating. They generally aff... more Traumatic injuries to the brachial plexus in adults are severely debilitating. They generally affect young individuals. A thorough understanding of the anatomy, clinical evaluation, imaging and electrodiagnostic assessments, treatment options and proper timing of surgical interventions will enable nerve surgeons to offer optimal care to patients. Advances in microsurgical technique have improved the outcome for many of these patients. The treatment options offer patients with brachial plexus injuries the possibility of achieving elbow flexion, shoulder stability with limited abduction and the hope of limited but potentially useful hand function.

Research paper thumbnail of Correlation between parameters of electrophysiological, histomorphometric and sciatic functional index evaluations after rat sciatic nerve repair

Arquivos de Neuro-Psiquiatria, 2006

The rat sciatic nerve is a well-established model for the study of recovery from peripheral nerve... more The rat sciatic nerve is a well-established model for the study of recovery from peripheral nerve injuries. Traditional methods of assessing nerve regeneration after nerve injury and repair, such as electrophysiology and histomorphometry, despite widely used in neural regeneration experiments, do not necessarily correlate with return of motor and sensory functions. The aim of this experimental study is to investigate the possible correlation between several parameters of peripheral nerve regeneration after repair of sectioned sciatic nerve in Wistar rat. A two-stage approach was used to obtain 17 parameters after electrophysiological, morphometric and sciatic functional index evaluations. Pearson's correlation analysis was performed between these results. Only two positives correlations between different classes of peripheral nerve assessments were noted, between sciatic functional index and proximal nerve fiber diameter (r=0.56, p<0.01) and between sciatic functional index a...

Research paper thumbnail of Electrophysiologic assessment of regeneration in rat sciatic nerve repair using suture, fibrin glue or a combination of both techniques

Arquivos de Neuro-Psiquiatria, 2005

We evaluated the repair of seccioned rat sciatic nerve by the comparison of electrophysiologic pa... more We evaluated the repair of seccioned rat sciatic nerve by the comparison of electrophysiologic parameters. The repair was effected with suture (group A), fibrin glue (group B) or a combination of both techniques (group C). The amplitude, latency and conduction velocity of the motor and nerve action potentials were assessed before the nerve section and at reoperation after 24 weeks. There was no difference between the groups when the nerve action potential was evaluated. Rats of group B presented better results than those of group A (p<0.05) when latency and the nerve conduction velocity assessed at the reoperation, and the ratio between the conduction velocity at the reoperation and before the nerve section in the motor action potential evaluation were measured. Animals of group C presented better results than those of group A when the ratio between the conduction velocity of motor action potential at the reoperation and before the nerve division was considered (p<0.05). No di...

Research paper thumbnail of Clinical Results of Transferring a Motor Branch of the Tibial Nerve to the Deep Peroneal Nerve for Treatment of Foot Drop

Neurosurgery, 2013

BACKGROUND: Foot drop is a very debilitating condition affecting patients' daily activities, ... more BACKGROUND: Foot drop is a very debilitating condition affecting patients' daily activities, and its treatment has been a challenge for neurosurgeons. Grafting the peroneal or sciatic nerve usually results in poor outcomes. Our previous anatomic study demonstrated the feasibility of transferring a motor branch of the tibial nerve to the deep peroneal nerve at the level of the popliteal fossa. OBJECTIVE: To demonstrate the outcomes obtained after the transfer of a branch of the tibial nerve to the peroneal nerve for recovery of foot drop. METHODS: A retrospective review of 13 patients with foot drop caused by injuries to a lumbar root or the sciatic or peroneal nerve, who underwent a transfer of the nerve of the soleus muscle to the deep peroneal nerve. The results were evaluated using the British Medical Research Council grading system. RESULTS: Three patients were lost to follow-up. Of the remaining 10 patients, the outcomes were considered good (Medical Research Council grade ...

Research paper thumbnail of Abstract Article

Effects of eliminating tension by means of epineural stitches A comparative electrophysiological ... more Effects of eliminating tension by means of epineural stitches A comparative electrophysiological and histomorphometrical study using different suture techniques in an animal model

Research paper thumbnail of Cervical Schwannoma of the Vagus Nerve: Two Illustrative Cases

Background: Cervical schwannoma is a rare and benign tumor exclusively developed from the cell of... more Background: Cervical schwannoma is a rare and benign tumor exclusively developed from the cell of Schwann that rarely involves the vagus nerve. Methods: We reported two illustrative cases and a brief literature review. Both patients presented with a history of painless palpable mass in the cervical region. Results: In both cases the lesions were diagnosed by means of imaging studies and were totally resected. Surgical findings and histopathology confirmed the diagnosis of vagus nerve schwannoma. There was no recurrence at five years of follow-up. In one case there was dysphonia that solved within six months after the surgery. Conclusion: Vagus nerve schwannomas are rare benign tumors. The enucleation technique is used to obtain the most functional preservation and complete excision without permanent deficit is possible even with the occurrence of large lesions.

Research paper thumbnail of Masseteric-Facial Anastomosis: A Report of Three Cases

Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery, 2021

Intoduction The pathways of the facial nerve are variable, and knowledge of that is essential. Th... more Intoduction The pathways of the facial nerve are variable, and knowledge of that is essential. The worst impact caused by facial paralysis is related to quality of life, especially regarding the self-esteem and social acceptance on the part of the patients, leading to social isolation and disruption on their mental health. Case Report A 33-year-old female patient, with a stage-T3 acoustic neurinoma, presented with a moderate dysfunction (grades II to III) according to the House-Brackmann (HB) Facial Nerve Grading System. A 43-year-old male patient, with a stage-T4B trigeminal schwannoma, underwent a resective surgery and presented grade-VI dysfunction according to the HB scale. And a female patient with a stage-T4A acoustic neurinoma presented grade-IV dysfunction according to the HB scale. Discussion We performed a literature review of papers related to surgeries for masseteric-facial nerve anastomosis and compiled the results in table; then, we compared these data with those obtai...

Research paper thumbnail of The nerve to the levator scapulae muscle as donor in brachial plexus surgery: an anatomical study and case series

Journal of Neurosurgery, 2021

OBJECTIVENerve transfers are commonly used in treating complete injuries of the brachial plexus, ... more OBJECTIVENerve transfers are commonly used in treating complete injuries of the brachial plexus, but donor nerves are limited and preferentially directed toward the recovery of elbow flexion and shoulder abduction. The aims of this study were to characterize the anatomical parameters for identifying the nerve to the levator scapulae muscle (LSN) in brachial plexus surgery, to evaluate the feasibility of transferring this branch to the suprascapular nerve (SSN) or lateral pectoral nerve (LPN), and to present the results from a surgical series.METHODSSupra- and infraclavicular exposure of the brachial plexus was performed on 20 fresh human cadavers in order to measure different anatomical parameters for identification of the LSN. Next, an anatomical and histomorphometric evaluation of the feasibility of transferring this branch to the SSN and LPN was made. Lastly, the effectiveness of the LSN-LPN transfer was evaluated among 10 patients by quantifying their arm adduction strength.RESU...

Research paper thumbnail of Treatment of radiation-induced brachial plexopathy with omentoplasty

Autopsy and Case Reports, 2020

An understanding of the climate conditions governing spatial variation in the reproductive perfor... more An understanding of the climate conditions governing spatial variation in the reproductive performance of plants can provide important information about the factors characterizing plant community structure, especially in the context of climate change. This study focuses on the effect of climate on the sexual reproductive output of Dactylis glomerata L., a perennial grass species widely distributed throughout temperate regions. An indirect space-for-time substitution procedure was used. Sixty mountain populations of the same target species were surveyed along an elevation gradient, and then, a relevant climate model was used to infer a potential response to climate change over time. Within each population, information on the number of stems, seed number and seed mass were collected. Resource investment in reproduction (RIR) was quantified as seed number × seed mass. A clear variation was found in the reproductive performance of D. glomerata along the elevational gradient: RIR improved with increasing temperature. The best model included only one term: the maximum temperature of the warmest month. This study demonstrates that mountain ecosystems offer particularly good opportunities to study climate effects over relatively short distances and suggests that warming will enhance D. glomerata reproductive output throughout its elevational range. Furthermore, it can be hypothesized that a potential migration of D. glomerata toward higher altitudes may occur in response to accelerated climate change.

Research paper thumbnail of Pain Threshold in Migraine and Tension-Type Headache by Pressure Algometry in Craniocervical Muscles and Peripheral Nerves in Both Genders

Journal of Neurology & Stroke, 2017

Patients and Methods Study design and Patients This was a prospective study with comparison of gr... more Patients and Methods Study design and Patients This was a prospective study with comparison of groups. The study population comprised a non-random and convenience sampling, consisting of the first 20 control patients, 25 migraine patients and 20 tension-type headache (TTH) patients (comparison group). Inclusion criteria Patients aged between 20 and 50 years, no complaint of headache (control), with migraine or tensional-type headache, according to the diagnostic criteria of International Classification of Headache Disorders (ICHD)-2 [7] and absence of abortive medication for at least 5 days were included in the study. Exclusion criteria Patients with psychiatric disorders, skin diseases (psoriasis, herpes zoster and leprosy that interfere with the perception of pain), patients with any type of secondary headache, abnormal neurological or neuroimaging examination, congenital

Research paper thumbnail of Estudo prospectivo comparando a utilização de fascículo do nervo ulnar isolado ou em associação com fascículo do nervo mediano para a restituição da flexão do antebraço nas lesões parciais pós-traumáticas do plexo braquial

Estudo prospectivo comparando a utilização de fascículo do nervo ulnar isolado ou em associação c... more Estudo prospectivo comparando a utilização de fascículo do nervo ulnar isolado ou em associação com fascículo do nervo mediano para a restituição da flexão do antebraço nas lesões parciais póstraumáticas do plexo braquial