Publication Trends of Research on Intrathecal Baclofen Therapy: A Bibliometric Analysis of the Literature

OBJECTIVE

The objective of this study was to analyze the trends in publications on intrathecal baclofen (ITB) therapy.

METHODS

We searched Elsevier's Scopus database in February 2022 to find articles focused on ITB therapy. Data extracted included citation count, publication year, author's country and income category, journal and its 5-year impact factor, research type, disease requiring ITB, and target population.

RESULTS

The analysis covered 615 articles from 1985 to 2022. The average citation count per article was 27.47 (95% confidence interval 23.75-31.18) and the mean impact factor was 4.54 (95% confidence interval 3.84-5.24). The majority (76.42%) were primary research, with 8.1% being interventional and 91.9% observational. Even so, one half of the top ten most cited were interventional. Secondary research and case reports made up 12.68% and 10.73% respectively, with narrative reviews making up most of the secondary research (79.48%). Only 1 study conducted a meta-analysis. The United States was the most prolific country. High-income countries published 96.42% of articles.

CONCLUSIONS

The rising number of ITB articles and citations indicates growing interest and expanding knowledge in this field. However, there's a notable scarcity of research from low- and middle-income countries, particularly those with high prevalence of ITB-treatable diseases. The need for more evidence to overcome potential barriers to ITB implementation is emphasized. Despite an increasing number of publications, a large proportion presented low levels of evidence, such as case reports and narrative reviews, highlighting the need for more rigorous research methods to solidify the evidence base for ITB therapy.

CD68 in Cerebral Aneurysms of Smokers and Nonsmokers: An Immunohistochemical Analysis

BACKGROUND

 There is some evidence indicating that inflammation of the aneurysmal wall is related to aneurysmal growth and rupture. The presence of CD68 may indicate greater inflammatory activity. The objective of this study is to evaluate CD68 immunoexpression in surgically resected brain aneurysms and its association with smoking.

METHODS

 The resected brain aneurysmal walls after microsurgical clipping were envoyed to immunohistochemistry investigation. The objective was to evaluate the expression of CD68 and CD34 antibodies. The associations between inflammatory markers, smoking, and rupture were tested using Fischer's exact test.

RESULTS

 CD68 immunoexpression in the tunica media was associated with larger aneurysms: 7.0 mm (7.0-9.0 mm) versus 5.0 mm (3.5-5 mm; p = 0.011). There was no statistically significant association between smoking and CD68 expression in the tunica media (p = 0.234) or in either the tunica media or the tunica intima (p = 0.628). There was also no statistically significant association between hemorrhagic presentation of the aneurysm and CD68 expression in the tunica media (p = 0.689) or in either the tunica media or the tunica intima (p = 0.348). Therefore, the presence of CD68-positive cells in the aneurysmal walls indicates an association with size, especially if the tunica media is exclusively compromised (p = 0.011).

CONCLUSION

 Immunohistochemistry investigation for CD68 antibodies was used to determine histiocytic infiltration. Adequately powered studies are necessary to further investigate the association between CD68-positive cells and both smoking history and hemorrhagic presentation of aneurysms.

Preoperative scale proposal based on clinical outcome for elderly patients with ruptured intracranial aneurysms undergoing microsurgery

INTRODUCTION

Life expectancy in individuals has increased in recent years. There is no consensus in the literature on the best treatment for a ruptured aneurysm in the elderly (> 60 years), but some places only have microsurgery as a therapeutic strategy. This work aims to develop a prognostic scale for ruptured intracranial aneurysms in the elderly.

MATERIAL AND METHODS

Two thousand five hundred thirty patients with subarachnoid hemorrhage were retrospectively evaluated in the last ten years, and 550 of them were elderly. We developed a prognostic scale from the analysis of medical records, clinical and tomographic features that had statistical significance. Glasgow Coma Outcome (GOS) was the outcome of interest and p value < 0,05 was considered statistically significant.

RESULTS

Five hundred fifty patients were evaluated, and the comorbidities that were independent variables for poor prognosis were smoking and arterial hypertension; clinical variables were Hunt-Hess, modified Rankin and Glasgow Coma Scale; tomographic was Fisher scale. Poor outcome was defined as GOS ≤ 3. Poor surgical outcomes were more remarkable in the high-risk factor categories, being 6.41 times higher among individuals who had 3 to 4 risk factors and 8.80 times higher among individuals with 5 to 6 risk factors.

CONCLUSION

In some vascular neurosurgery services worldwide, microsurgery is the only therapeutic option. This scale aimed at the elderly patient individualizes the treatment and can predict the clinical outcome in ruptured intracranial aneurysms.

Dyke-Davidoff-Masson Syndrome: Main clinical and radiological findings- systematic literature review

INTRODUCTION

Dyke-Davidoff-Masson syndrome (DDMS), or cerebral hemiatrophy, was first described in 1933. It is characterised by cerebral injury that causes hypoplasia in one of the cerebral hemispheres. The disease has different clinical degrees and two aetiologies: congenital and acquired. Radiological findings depend on the degree of injury and the patient's age at the time.

OBJECTIVE

To provide information on the main clinical and radiological characteristics of this disease.

METHODS

A systematic review of the PubMed, MEDLINE, and LILACS databases was conducted using only one keyword. Dyke-Davidoff-Masson syndrome. A total of 223 studies were identified, and the results are presented in tables and graphics.

RESULTS

The mean age of the patients was 19.44 (0-83 years), and the majority were male (55.32%). The most common types of epileptic seizures were generalised tonic-clonic seizures (31 cases), focal impaired awareness seizures (20 cases), focal motor seizures (13 cases), focal to bilateral tonic-clonic seizures (nine cases), and focal myoclonic seizures (one case). The main features of the disease were rapid deep tendon reflexes and extensor cutaneous-plantar tendon reflexes (30 cases - 16%), contralateral hemiparesis or hemiplegia (132 cases - 70%), gait alterations (16 cases - 9%), facial paralysis (nine cases - 5%), facial asymmetry (58 cases - 31%), limb asymmetry (20 cases - 11%), delayed developmental milestones (39 cases - 21%), intellectual disability (87 cases - 46%), and language/speech disorders (29 cases - 15%). Left hemisphere atrophy was the most prevalent.

CONCLUSION

DDMS is a rare syndrome, and several questions regarding this disease remain unanswered. This systematic review aims to elucidate the most common clinical and radiological aspects of the disease and emphasises the need for further investigation.

B-Cell Lymphoma Intramedullary Tumor: Case Report and Systematic Review

Intramedullary tumors represent the major cause of spinal cord injuries, and its symptoms include pain and weakness. Progressive weakness may concomitantly occur in the upper and lower limbs, along with lack of balance, spine tenderness, sensory loss, trophic changes of extremity, hyperreflexia, and clonus. The study protocol was in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A systematic search of the MEDLINE electronic database was performed to identify the studies reporting the clinical features of children and adults who presented with an intramedullary lymphoma. Twenty-one studies were included, reporting 25 cases. Manuscripts were excluded if the full-text article was not available, original data were not reported (e.g., review articles), or if the main disease was not intramedullary lymphoma. A structured data extraction form was employed to standardize the identification and retrieval of data from manuscripts. To enlighten the discussion, a case is also presented. An 82-year-old woman with Fitzpatrick skin type II, diagnosed and treated for non-Hodgkin's lymphoma 7 years ago, was admitted with mental confusion and memory loss for the past 2 months-evolving with recurring falls from her own height. One day before admission, she displayed Brown-Séquard syndrome. An expansive lesion from C2 to C4 in the cervical spinal cord was found and a hypersignal spinal cord adjacent was described at the bulb medullary transition to the C6-C7 level. A primary spinal cord tumor was considered, as well as a melanoma metastasis, due to the lesion's flame pattern. The patient presented a partial recovery of symptoms and a reduction of the spinal cord edema after being empirically treated with corticosteroids, but the lesion maintained its extent. Subsequently, a large diffuse B-cell lymphoma with nongerminal center was found in open body biopsy, infiltrating neural tissue. The main objective of the present study is to report a surgical case treated for a large diffuse B-cell lymphoma, in addition to presenting the results of a systematic review of primary intramedullary spinal cord lymphoma.

Impact of a cell cycle and an extracellular matrix remodeling transcriptional signature on tumor progression and correlation with EZH2 expression in meningioma

OBJECTIVE

The authors searched for genetic and transcriptional signatures associated with tumor progression and recurrence in their cohort of patients with meningiomas, combining the analysis of targeted exome, NF2-LOH, transcriptome, and protein expressions.

METHODS

The authors included 91 patients who underwent resection of intracranial meningioma at their institution between June 2000 and November 2007. The search of somatic mutations was performed by Next Generation Sequencing through a customized panel and multiplex ligation-dependent probe amplification for NF2 loss of heterozygosity. The transcriptomic profile was analyzed by QuantSeq 3' mRNA-Seq. The differentially expressed genes of interest were validated at the protein level analysis by immunohistochemistry.

RESULTS

The transcriptomic analysis identified an upregulated set of genes related to metabolism and cell cycle and downregulated genes related to immune response and extracellular matrix remodeling in grade 2 (atypical) meningiomas, with a significant difference in recurrent compared with nonrecurrent cases. EZH2 nuclear positivity associated with grade 2, particularly with recurrent tumors and EZH2 gene expression level, correlated positively with the expression of genes related to cell cycle and negatively to genes related to immune response and regulation of cell motility.

CONCLUSIONS

The authors identified modules of dysregulated genes in grade 2 meningiomas related to the activation of oxidative metabolism, cell division, cell motility due to extracellular remodeling, and immune evasion that were predictive of survival and exhibited significant correlations with EZH2 expression.

Is percutaneous balloon compression better than microvascular decompression to treat trigeminal neuralgia? A systematic review and meta-analysis

BACKGROUND

Trigeminal neuralgia (TN) is a neuropathic pain that affects one or more branches of the trigeminal nerve. Surgical options after pharmacological failure are Microvascular Decompression (MVD) or percutaneous procedures, which include Balloon Compression (PBC). This study aims to describe pain outcomes and complications after PBC and MVD procedures for patients with trigeminal neuralgia.

METHODS

We performed a systematic review and meta-analysis on PubMed, EMBASE, LILACS, and Web of Science databases up to April 2022, following PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and meta-Analysis). Articles that separately describe pain outcome for MVD and PBC were included. MINORS tool was used for bias assessment. Meta-analysis results are presented in forest plot and funnel plot.

RESULTS

853 studies were assessed for screening, and 11 studies met the inclusion criteria for this review. A total of 1046 patients underwent PBC and 1324 underwent MVD. The subgroup analysis for patients without multiple sclerosis shows that MVD was associated with lower number of patients with pain than PBC, with an OR value of 0.54 (95 % CI 0.34-0.84). All other analyses evidenced a tendency for better outcomes after the MVD procedure, but with no statistically significant difference.

CONCLUSION

Considering short and long pain relief, recurrence of pain and total complications for MVD and PBC, our study found that MVD is the best surgical option available for trigeminal neuralgia.

Miller–Fisher syndrome after first dose of Oxford/AstraZeneca coronavirus disease 2019 vaccine: a case report

Introduction

Miller-Fisher Syndrome (MFS) is a variant of Guillain–Barré syndrome (GBS), an acute immune-mediated neuropathy, which manifests as a rapidly evolving areflex motor paralysis. This syndrome presents as a classic triad: ophthalmoplegia, areflexia, and ataxia. MFS is usually benign and self-limited.

Case report

A Caucasian patient was admitted to our hospital with the flu, loss of bilateral strength in the lower limbs and upper limbs and sudden-onset ataxia 7 days after receiving a first dose of the Oxford/AstraZeneca COVID-19 vaccine. On neurological examination, the patient had Glasgow Coma Scale score of 15, with absence of meningeal signs; negative Babinski sign; grade 2 strength in the lower limbs and grade 4 strength in the upper limbs; axial and appendicular cerebellar ataxia; and peripheral facial diparesis predominantly on the right, without conjugate gaze deviation. Cerebrospinal fluid (CSF) was collected on admission, and analysis revealed albuminocytological dissociation with CSF protein of 148.9 mg/dL; leukocytes, 1; chlorine, 122; glucose, 65 mg/mL; red cells, 2; and non-reactive venereal disease research laboratory test result. The COVID-19 IgG/IgM rapid immunological test was negative. Electroneuromyography revealed a recent moderate-grade and primarily sensory and motor demyelinating polyneuropathy with associated proximal motor block.

Discussion and conclusion

Miller-Fisher Syndrome may be related to events other than infections prior to neuropathy, as in the case reported here. The patient presented strong correlations with findings for MFS reported in the literature, such as the clinical condition, the results of electroneuromyography, and results of the CSF analysis typical for MFS. When treatment was provided as proposed in the literature, the disease evolved with improvement. Ultimately, the diagnosis of incomplete MFS was made, including acute ataxic neuropathy (without ophthalmoplegia).

Abordajes quirúrgicos de los meningiomas petroclivales Parte 2: revisión narrativa y lo que aprendimos con 30 casos

Antecedentes:

La resección quirúrgica de los meningiomas petroclivales es un desafío debido a su ubicación profunda y su relación con las estructuras neurovasculares vitales. Por lo general, son lesiones benignas, pero pueden involucrar o infiltrar huesos en la base del cráneo, la duramadre y el tronco encefálico. Esto hace que la extirpación total sea muy difícil o imposible sin causar déficits neurológicos. El objetivo de este estudio es revisar los abordajes quirúrgicos utilizados para tratar los meningiomas petroclivales y las lecciones que hemos aprendido en el manejo quirúrgico de 30 casos.

Métodos:

Serie de casos de 30 meningiomas petroclivales. Al comienzo de nuestra serie, utilizamos el abordaje petroso para todos los casos, pero con la adquisición de experiencia comenzamos a indicar cada vez más el abordaje retrosigmoideo, reservando los abordajes petrosos y cráneo-orbitocigomático para casos seleccionados.

Resultados:

Debido a la dificultad de acceso, los meningiomas petroclivales generalmente requieren diferentes abordajes quirúrgicos y presentan diferentes dificultades quirúrgicas. Hay tres abordajes principales: fronto-orbito-cigomático y variantes; petroso y variantes; y retrosigmoideo, pudiendo ser combinados. La elección del abordaje quirúrgico generalmente se basa en la ubicación y extensión del tumor, la forma del cráneo y la participación de las estructuras venosas, y la experiencia del cirujano.

Conclusión:

Los meningiomas petroclivales son raros y complejos en la base del cráneo. Elegir el abordaje correcto es crucial para un resultado quirúrgico exitoso.

Aquaporin-4 Expression in Meningioma Malignancy Progression

Objectives The aim of the present study is to analyze if aquaporin-4 (AQP4) may also be a tumor progression marker for meningiomas.

Methods This is an immunohistochemistry study realized at the Universidade de São Paulo, São Paulo, state of São Paulo, Brazil: frozen meningioma samples from 81 patients (57 females and 24 males, age range from 22 to 81 years old, average 56.5 ± 14.1 years old), including 57 meningiomas World Health Organization (WHO) grade I (GI); 19 grade II (GII), and 5 grade III (GIII) were analyzed. The relative expression level of AQP4 was analyzed by quantitative polymerase chain reaction (qPCR), using the SYBR Green approach and for staining detection. Tissue sections were routinely processed and subjected to antigen retrieval.

Results The expression of AQP4 in meningioma samples ranged from 0 to 10.26, with a median of 0.001 in GI cases, of 0.008 in GII cases, and of 0.006 in GIII cases. Although not statistically significant (p = 0.942), GI meningiomas have a lower median AQP4 expression level than higher malignant grade cases.

Conclusion The AQP4 gene and protein expressions presented no association with meningioma malignant progression.

Callosotomy vs Vagus Nerve Stimulation in the Treatment of Lennox-Gastaut Syndrome: A Systematic Review With Meta-Analysis

BACKGROUND

Lennox-Gastaut syndrome (LGS) is a severe drug-resistant epileptic syndrome. Palliative treatments such as corpus callosotomy (CC) and vagus nerve stimulation (VNS) have emerged as treatments to reduce the number of seizures in patients. The aim of this study is to compare the effectiveness of CC and VNS in patients with LGS studied in the last 30 years.

MATERIALS AND METHODS

We conducted a systematic review with meta-analysis and collected papers from PubMed (MEDLINE), Ovidsp, Web of Science, and Cochrane Library data bases. The articles analyzed were published between January 1990 and December 2020. Keywords were chosen based on internal and external validation in the PubMed data base (the analysis is available in the Supplementary Data Supplementary Appendix). Prospective or retrospective case reports (n ≥ 2), case series, cohort studies, or case-control studies involving patients with LGS were included in the analysis. We selected studies that had no age or sex restriction and that provided data on seizures before and after treatments. Studies not written in English, published without peer review, or not indexed in the data bases were excluded. Other exclusion criteria were the absence of seizure data and the impossibility of extracting this information from the studies. To analyze the results, we used the random-effects model based on the assessment of heterogeneity (I² statistics) in two scenarios. In scenario 1, we assessed the incidence of patients with a seizure reduction ≥ 50%; in scenario 2, we assessed the incidence of patients with a seizure reduction > 0%.

RESULTS

Of the 7418 articles found using the keywords, 32 were considered eligible. Of these, 18 articles were on VNS (175 patients) and 14 on CC (107 patients). For scenario 1 (seizure reduction ≥ 50%), CC had an incidence of 65% (95% CI, 37%-94%), with an I² value of 82.7%; VNS had an incidence of 34% (95% CI, 11%-57%), with an I² value of 80.7%. For scenario 2 (seizure reduction > 0%), CC had an incidence of 80% (95% CI, 58%-100%), with an I² value of 84.7%; VNS had an incidence of 64% (95% CI, 38%-89%), with an I² value of 90.8%. There was an overlap of confidence intervals, with no statistical difference between the treatments in both scenarios.

DISCUSSION

Our analysis of LGS showed that the CC and VNS treatments are significantly beneficial to reducing seizures, without superiority between them.

Abordajes quirúrgicos de meningiomas petroclivales parte 1: anatomía microquirúrgica

Antecedentes:

Los meningiomas petroclivales son tumores benignos cuyo tratamiento microquirúrgico es uno de los mayores retos de la neurocirugía. El conocimiento profundo de la anatomía microquirúrgica y los abordajes quirúrgicos para el tratamiento de estos tumores es la primera etapa de aprendizaje para un manejo ideal. Este artículo se divide en dos partes: la primera parte presentará los resultados de la anatomía microquirúrgica relevantes para el manejo de los meningiomaspetroclivales. En la segunda parte, los autores correlacionan esta anatomía con 30 casos de meningiomas petroclivales operados por el autor principal (GRI).

Métodos:

Se disecaron ocho cabezas de cadáveres utilizando un microscopio quirúrgico en el laboratorio de microcirugía de la University of Arkansas for Medical Sciences. En los cerebros y en todas las cabezas, se inyectó silicona de colores para resaltar la diferencia entre las arterias y las venas. Los cadáveres fueron colocados en un fijador craneal tipo Mayfield, simulando el posicionamiento quirúrgico de los abordajes craneo-órbito-cigomatico, petrosectomía anterior y posterior y retrosigmoideo. Otras ocho cabezas de cadáveres fueron formolizadas y con los vasos inyectados con silicona de colores. Se realizaron los abordajes petroso anterior, petroso posterior y craneo-órbito-cigomático.

Resultados:

En el manejo de los meningiomas petroclivales se utilizan tres abordajes quirúrgicos principales: abordaje pterional y sus variantes, abordaje petroso y sus variantes y abordaje retrosigmoideo. Los abordajes endonasales endoscópicos extendidos tienen factores limitantes para su uso en este tipo de procedimiento. Para racionalizar la elección del abordaje quirúrgico, dividimos el clivus en tercios superior, medio e inferior.

Conclusíon:

Varios abordajes quirúrgicos dan acceso a la regiónpetroclival. El conocimiento práctico de la anatomía de esta región adquirido en el laboratorio de microcirugía es parte fundamental del cirujano que se propone operar meningiomas petroclivales.

Cirurgia com neurofisiologia intraoperatória para ressecção microcirúrgica dos gliomas de alto grau de área motora em pacientes desacordados com anestesia geral (asleep)

Introdução: Os gliomas difusos são tumores primários do sistema nervoso central, que, apesar da melhoria das técnicas para os tratamentos, continuam como desafios para a medicina dados os seus padrões dinâmicos de crescimento e comportamento. Atualmente, uma das alternativas de tratamento estudadas pauta-se na porcentagem da ressecção e na área eloquente envolvida. A porcentagem de ressecção é um importante fator prognóstico independente que define a sobrevida nos pacientes. Objetivo: Mostrar a casuística da abordagem cirúrgica asleep de tumores em área motora. Método: Estudo retrospectivo em pacientes submetidos a ressecção cirúrgica asleep de gliomas de alto grau, com monitoração eletrofisiológica intraoperatória somatossensitivo motora, com ressecção dos tipos parcial, subtotal e total, por meio de craniotomia e microcirurgia. A análise dos resultados baseou-se na avaliação da evolução pós-operatória pela Escala de Karnofsky. Resultados: Na amostra verificada, pode-se aventar que a técnica operatória asleep é segura na abordagem nas áreas motoras. Todos os pacientes que apresentaram déficits evoluíram para óbito em razão do caráter agressivo da doença. Conclusão: Pode-se concluir que a técnica operatória asleep é segura quanto à abordagem nas áreas motoras, com complicação intraoperatória extremamente baixa e evolução prognóstica a depender da agressividade inicial do tumor.

Success of lateral cervical spinal cord stimulation for the treatment of chronic neuropathic refractory pain

Background:

Spinal cord stimulation (SCS) is traditionally performed by implanting surgical leads along the midline of the spinal cord, over the dorsal columns. Here, we present a patient who successfully underwent lateral cervical SCS to treat chronic refractory neuropathic pain.

Methods:

A 46-year-old female, with a schwannoma involving the right axillary nerve, presented with a chronic refractory right upper extremity pain syndrome. The tumor was located between the fibers of the teres minor and the posterior deltoid, and measured 2.2 cm in diameter. After 8 months of analgesics, opioids, physiotherapy, and acupuncture, the patient underwent surgery; however, the tumor was unresectable (i.e., due to significant adjacent vascular/neural structures). Three months later, she had a midline C6-C7 laminectomy for placement of a right-sided epidural SCS lead (i.e., containing 16 electrode contacts).

Results:

Within 4 days following this SCS procedure, the patient’s pain completely resolved; at 10 postoperative months, she still remains pain free.

Conclusion:

Lateral SCS at the C6-C7 level provided a safe and effective option for the relief of chronic neuropathic pain attributed to an unresectable schwannoma of the right axillary nerve in a 46-year-old female.

Rare complication of ventriculoperitoneal shunt: Ectopic distal catheter in a Grynfeltt hernia - case report

Background

Ventriculoperitoneal shunts (VPSs) insertion is the most common used intervention in cases of hydrocephalus. The main postoperative complications are infections and catheter obstructions. Although the literature has well-documented cases describing migration of the distal catheter, this rare presentation can become more confusing when occurring in conjunction with some unusual preexistent morbidity in the patient, as a Grynfeltt hernia.

Case Description

This study reports a rare case of a VPS postoperative migration, in which the distal catheter exits the abdominal cavity through a Grynfeltt hernia. This condition was not discovered until the catheter fistulated through the overlying skin. The Grynfeltt hernia is the most uncommon among the lumbar ones and it's asymptomatic in the majority of the cases, being hardly diagnosed.

Conclusion

The unusualness of the reported case deserves furthermore discussion to properly evaluate these underlying mechanisms of catheter migration.

Skin erosion in deep brain stimulation procedures: Using the temporalis muscle to treat this complication - A technical note

Background:

Skin erosion is a common complication after deep brain stimulator procedures. Despite being a relatively common event, there is no standard surgical technique or a widely accepted guideline for managing this kind of complication.

Methods:

We describe a case of cutaneous erosion in the connector’s site of deep brain stimulation case, surgically managed with anterior displacement of the connectors and overlapping and wrapping the connections within the temporal muscle.

Results:

Postoperatively, the patient did well and achieved complete resolution of the skin erosion, with no signs of infection or new skin lesions.

Conclusion:

This technique demonstrated to be effective in this case in the long-term follow-up.

Rosai-Dorfman disease mimicking images of meningiomas: Two case reports and literature review

Background:

Rosai-Dorfman disease (RDD) is a rare non-Langerhans cell histiocytic proliferative disorder classically as a massive cervical lymphadenopathy. However, over the years, extranodal locations were confirmed with the central nervous system involvement in less than 5% of cases, which is marked as a significant differential diagnosis of meningiomas, with which they are widely confused due to the similarity of their radiological images.

Case Description:

We report a 37-year-old man and 45-year-old man who were diagnosed with intracranial RDD but whose radiological images mimic meningiomas, requiring anatomopathological and tumor’s immunohistochemistry for definitive diagnosis. Moreover, a review of 184 publications with 285 cases of intracranial involvement of this disease was also performed, comparing these findings with those brought in the previous studies.

Conclusion:

Intracranial Rosai-Dorfman tumors should always be remembered as differential diagnosis of meningiomas since they are similar radiologically and macroscopically. Once remembered and diagnosed, the lesion must be treated following the same pattern of resection done in meningiomas and, treatment’s differences will not occur in the surgical excision technique, but in complementary chemotherapy implementation, radiotherapy, and even with radiosurgery aid, depending on the case. Thus, it is possible to obtain better results than with just the isolated surgical procedure.

Dravet syndrome and Dravet syndrome-like phenotype: a systematic review of the SCN1A and PCDH19 variants

Dravet syndrome (DS) is a rare and severe epileptic syndrome of childhood with prevalence between 1/22,000 and 1/49,900 of live births. Approximately 80% of patients with this syndrome present SCN1A pathogenic variants, which encodes an alpha subunit of a neural voltage-dependent sodium channel. There is a correlation between PCDH19 pathogenic variants, encodes the protocadherin 19, and a similar disease to DS known as DS-like phenotype. The present review aims to clarify the differences between DS and DS-like phenotype according to the SCN1A and PCDH19 variants. A systematic review was conducted in PubMed and Virtual Health Library (VHL) databases, using "Dravet Syndrome" and "Severe Myoclonic Epilepsy in Infancy (SMEI)" search words, selecting cohort of studies published in journal with impact factor of two or greater. The systematic review was according to the Preferred Reporting Items for Systematic Review and Meta-Analysis recommendations. Nineteen studies were included in the present review, and a significant proportion of patients with DS-carrying SCN1A was greater than patients with DS-like phenotype-harboring PCDH19 variants (76.6% versus 23.4%). When clinical and genetic data were correlated, autism was predominantly observed in patients with DS-like-carrying PCDH19 variants compared to SCN1A variant carriers (62.5% versus 37.5%, respectively, P-value = 0.044, P-value corrected = 0.198). In addition, it was noticed a significant predisposition to hyperthermia during epilepsy crisis in individuals carrying PCDH19 variants (P-value = 0.003; P-value corrected = 0.027). The present review is the first to point out differences between the DS and DS-like phenotype according to the SCN1A and PCDH19 variants.

An unusual case of lead migration in occipital nerve stimulation: A case report and literature review

Background:

Lead migration is a complication associated with occipital nerve stimulation (ONS). We present a rare case in which fibrosis in the stress relief loop caused lead migration in the treatment of occipital neuralgia.

Case Description:

A 30-year-old woman with a 5-year history of refractory occipital neuralgia, who had been under ONS therapy for 2 months, presented with a sudden onset of typical occipital neuralgia pain associated with cervical muscles spasms and myoclonus. A skull radiography showed lead migration. The patient underwent surgery for lead repositioning. During surgery, we identified extensive fibrosis throughout the stress relief loop that produced several constriction points. The fibrosis in the stress relief loop increased tension on the lead during head-and-neck movement, causing progressive migration of the lead.

Conclusion:

Although lead migration is a common complication of ONS, its association with fibrosis in the stress relief loop has not, to the best of our knowledge, been reported before. Lead migration can directly affect treatment outcome and it is, therefore, important to fully understand the possible mechanisms that can cause it and how to promptly manage them.

Single-Nucleotide Variants in microRNAs Sequences or in their Target Genes Might Influence the Risk of Epilepsy: A Review

Single-nucleotide variant (SNV) is a single base mutation at a specific location in the genome and may play an import role in epilepsy pathophysiology. The aim of this study was to review case-control studies that have investigated the relationship between SNVs within microRNAs (miRs) sequences or in their target genes and epilepsy susceptibility from January 1, 2010 to October 31, 2020. Nine case-control studies were included in the present review. The mainly observed SNVs associated with drug-resistant epilepsy (DRE) risk were SNVs n.60G > C (rs2910164) and n.-411A > G (rs57095329), both located at miR-146a mature sequence and promoter region, respectively. In addition, the CC haplotype (rs987195-rs969885) and the AA genotype at rs4817027 in the MIR155HG/miR-155 tagSNV were also genetic susceptibility markers for early-onset epilepsy. MiR-146a has been observed as upregulated in human astrocytes in epileptogenesis and it regulates inflammatory process through NF-κB signaling by targeting tumor necrosis factor-associated factor 6 (TRAF6) gene. The SNVs rs2910164 and rs57095329 may modify the expression level of mature miR-146a and the risk for epilepsy and SNVs located at rs987195-rs969885 haplotype and at rs4817027 in the MIR155HG/miR-155 tagSNV could interfere in the miR-155 expression modulating inflammatory pathway genes involved in the development of early-onset epilepsy. In addition, SNVs rs662702, rs3208684, and rs35163679 at 3'untranslated region impairs the ability of miR-328, let-7b, and miR-200c binding affinity with paired box protein PAX-6 (PAX6), BCL2 like 1 (BCL2L1), and DNA methyltransferase 3 alpha (DNMT3A) target genes. The SNV rs57095329 might be correlated with DRE when a larger number of patients are evaluated. Thus, we concluded that the main drawback of most of studies is the small number of individuals enrolled, which lacks sample power.

Assessment of hemorrhagic onset on meningiomas: Systematic review

OBJECTIVE

To review the data published on the subject to create a more comprehensive natural history of the haemorrhagic onset of meningiomas (IVMs).

PATIENTS AND METHODS

A Medline search up to June 2020, using the search term "bleeding meningioma," returned 136 papers. As a first selection step, we adopted the following inclusion criteria: series and case reports about bleeding meningioma. Papers written in other languages but with abstracts written in English were also evaluated.

RESULTS

A total of 190 tumours were evaluated, specifically 109 tumours from female patients and 81 tumours from male patients with a ratio of 1.34 female to 1.0 male (mean age of 54.86 ± 16.1years old). The majority were located in the convexity (129-67.9 %). Among the 190 tumours evaluated, 171 patients (90 %) presented with GI tumours, with a predominance of the meningothelial subtype (32.6 %). Nine patients (4.7 %) presented with grade GII tumours, and 10 (5.3 %) presented with GIII tumours. The most prevalent type was intracerebral haemorrhage (ICH) at 50 %, followed by subdural at 27.36 %; the mortality rate was 13.1 % (25 deaths), the distribution of both location (prevalence of convexity: 18-72 %) and histopathology (grade 1: 22-88 %).

CONCLUSION

These tumours follow the histopathological distribution of meningiomas, in general. The age distribution shows prevalence among the adult population but with a greater proportion in the elderly. The fact that the overwhelming majority of cases involve meningiomas with a benign histological subtype is noteworthy. Another relevant factor observed is that most reports are from Asian origin.

The single nucleotide variant n.60G>C in the microRNA-146a associated with susceptibility to drug-resistant epilepsy

OBJECTIVE

The aim of this study was to evaluate single nucleotide variants (SNVs) n.-411A > G (rs57095329) and n.60 G > C (rs2910164) in microRNA (miR)-146a, related to suppressing of TRAF6 with risk for epilepsy, as well as miR-146a and TRAF6 levels.

METHODS

DNAs were extracted from epileptogenic tissues and blood leukocytes from drug-resistant epilepsy patients and healthy-individuals, respectively. Genotypes were identified by real-time PCR. Hardy-Weinberg equilibrium (HWE) and Fisher or X² tests evaluated the difference between groups. The disease risk was assessed by odds ratio (OR) with 95 % confidence interval (95 %CI). The prognostic impact on probability seizure-free survival (PSF) was evaluated by Kaplan-Meier and log-rank tests.

RESULTS

For rs57095329 both control and patient samples were not in HWE (p < 0.05) and the genotypes prevalence was similar in patients and controls (p>0.05). For rs2910164, control samples were in HWE (p = 0.61), contrasting with patients (p = 0.03), and similar frequencies of wild-type homozygous (GG) (43.4 % vs. 34.4 %, p = 0.2) and variant (CC) genotypes (8.0 % vs. 6.6 %, p = 0.6) were observed in patients and controls, respectively. However, increased frequency of heterozygous (GC) was observed in patients compared to controls (59.0 % vs. 42.7 %, p = 0.04) with 1.98 (95 %CI=1.09-3.57) risk for epilepsy. The miR-146a expression level in the epileptogenic tissues was lower in the GC (p = 0.02) and CC (p = 0.09) compared to GG genotype. TRAF6 expression level was higher in CC than in GG genotype (p = 0.09). Interestingly, there was an increased frequency of patients harboring GC genotype and less time until surgery compared to patients harboring GG or CC (36.06 % vs. 11.5 %, p = 0.01), confirmed by PSF (p = 0.04).

CONCLUSIONS

The GC genotype for SNV rs2910164 appears associated with susceptibility to drug-resistant epilepsy due to the decreased MIR146a expression, favoring NF-kB pathway through TRAF6.

Cyclin E1 expression and malignancy in meningiomas

OBJECTIVE

The aim of the present study was to analyze if the pathway Skp2-p27-cyclin E1 could also be a tumor progression marker for meningiomas.

PATIENTS AND METHODS

We used quantitative real-time PCR to assess the relative expression levels of the genes coding for cyclin E1 (CCNE1), Skp2 (SKP2), and p27 (P27). The expression levels were compared in grades I to III meningiomas and among different histological subtypes of grade I meningiomas.

RESULTS

Anaplastic meningiomas accounted for 4.9%, atypical meningiomas for 23.5% and grade I meningiomas for 71.6%.CCNE1 expression level was significantly higher in grade II compared to grade I meningiomas (p = 0.0027), and its expression level reliably predicts grade II meningiomas (ROC AUC = 0.731, p = 0.003). CCNE1 expression also correlated with SKP2 and P27 expression levels in grade I meningiomas (r = 0.539, p < 0.0001 and r = 0.687, p = <0.0001, respectively for CCNE1/SKP2 and CCNE1/P27, Spearman's test). Fibrous subtype among grade I meningiomas presented the highest expression levels of CCNE1, SKP2 and P27. Higher expression of cyclin E1 protein was detected in the nuclei of atypical meningiomas compared to grade I meningiomas.

CONCLUSIONS

CCNE1 expression level predicts meningioma malignancy, and the fibrous subtype presents the highest gene expression levels among grade I meningiomas.

Spinal Cord Stimulation in Pregnant Patients: Current Perspectives of Indications, Complications, and Results in Pain Control: A Systematic Review

Spinal cord stimulation (SCS) has been described as a valuable neuromodulator procedure in the management of chronic medically untreated neuropathic pain. Although the use of this technique has been published in many papers, a question still remains regarding its applicability in pregnant patients. The goal of this paper is to discuss the risks, complications, and results as well as the prognosis of SCS in pregnant patients. We performed a systematic review from 1967 to 2018 using the databases MEDLINE, LILACS, SciELO, PubMed, and BIREME, utilizing language as selection criteria. Eighteen studies that met our criteria were found and tabulated. SCS is a reversible and adjustable surgical procedure, which results in patients that demonstrated a significant effect in the reduction of pain intensity in pregnant patients. The etiologies most frequent were complex regional pain and failed back pain syndromes, which together represented 94% of analyzed cases. The technical complications most frequent were lead migration (3%, n = 1). Regarding the risks, the authors did not show significative factors among the categorical variables that can suggest a teratogenicity, while the maternal risks have been associated to the consequences of technical complications due to, among other factors, improvement of abdominal pressure during pregnancy and delivery. Finally, although there are not significative cohorts of pregnant patients, the procedure is still an effective surgical approach of neuropathic pain associated to lower rates of complications and significative improvement in the quality of life of patients during pregnancy.

Giant dumbbell C2C3 neurofibroma invading prebulbar cistern: Case report and literature review

Background:

Neurofibromatosis 1 (NF1) has a broad spectrum of clinical manifestations, most typically involving café-au-lait spots and skin neurofibromas. Only 2% of patients with NF1 have symptomatic spinal tumors.

Case Description:

A patient with a previous diagnosis of NF1 presented with cervicalgia, dysphagia/mild dysphonia, gait alteration, and progressive hypoesthesia involving all four limbs. The magnetic resonance documented a giant dumbbell neurofibroma arising between the C2 and C3 levels which extended toward the foramen magnum, causing medullary and bulbar compression. The major challenge of surgical management was the enormous size and location this C2–C3 (5 cm × 4 cm × 5.1 cm) lesion.

Conclusions:

Compression of the foramen magnum attributed to a dumbbell giant spinal neurofibroma at the C2C3 level resulting in prebulbar cisterns should be among the differential diagnostic considerations for patients presenting with tetraparesis and underlying NF1.

Multiple Intracranial Meningiomas: A Case Series and Review of the Literature

OBJECTIVE

To review the published data to create a more comprehensive natural history of multiple meningiomas (MM).

METHODS

A review of MM published until now was carried out through a Medline search up to August 2018. The use of the "multiple meningiomas" keyword returned 278 articles, and the characteristics analyzed in our present cohort were searched on those publications. Articles without detailed description of clinical findings, neuroimaging confirmation of tumor multiplicity, follow-up at least of 5 years, and clear description of clinical findings were excluded. We added series to this review.

RESULTS

293 patients with MM were analyzed: 220 women and 73 men, with a total of 932 tumors (3.1 tumors per patient). The majority of tumors were located in the convexity (653% to 74.5%). The total number of tumors treated was 429 (43.9%): 338 (78.8%) by surgical resection and 91 (21.2%) by radiotherapy. Histopathologic description was available in 303 of 429 cases, being grade I in 272 (90.3%) cases, with a predominance of the meningothelial subtype (30.7%). Tumor recurrence was described in 32 (8.07%) among 397 and only 10 deaths (3.4%) of 281 reported cases, where this characteristic was evaluated.

CONCLUSIONS

World Health Organization grade I predominance was observed among multiple meningiomas in similarity to single meningiomas. Only a fraction of MM patients (43.89%) needed treatment. A benign tumor behavior was corroborated by the observed low frequency of recurrence and mortality.

Optogenetics: the new molecular approach to control functions of neural cells in epilepsy, depression and tumors of the central nervous system

The optogenetic tools have been described as valuable techniques to study neural activity through light stimulation, as well as potential neuromodulator approaches in the management of several central nervous system (CNS) diseases. Since the first bacteriorhodopsin protein described as a single-component light-activated regulator of transmembrane ion flow description, in 1980's, the focus has been on channel proteins for neurobiology; however, the advances in engineering techniques showed involvement changes in cellular biological behavior in several types of proteins involved in cell cytoskeleton regulation, motility and gene expression. Although the use of this technology has been published in many papers, a question still remains regarding real results and potential clinical applicability in CNS diseases, as well as the publications scarcity that systematically analyses the published results. Lastly, the aim of this review is to discuss the experimental results, molecular mechanisms and potential clinical applications of optogenetic tools in epilepsy and depression treatment, as well as its applicability in the treatment of CNS tumors.

Microsurgical Management of Trigeminal Schwannoma: Cohort Analysis and Systematic Review

Background  Trigeminal schwannomas are benign tumors with a predilection for women between 40 and 60 years of age and account for less than 0.5% of all intracranial tumors. Clinical presentation depends on size and location, and typical symptoms are ipsilateral hypesthesia, headache, and facial pain. Clinical features and imaging usually make the Diagnosis. Methods  A retrospective cohort analysis of 14 patients treated at our institution between January 1999 and October 2016 was performed, with a critical and systematic review of data from the literature, focusing on articles published over the same period. Results  Fourteen patients were included in our series comprised of mostly women with a mean age of 40 years. Lesion size ranged from 3 to 6.5 cm (mean 4.6 cm). Clinical status of patients was evaluated and also rated based on the Karnofsky Perfomance Scale with values greater than 90% found in all patients pre and postoperatively. Surgery was our treatment of choice, and gross total resection was achieved in 71% of patients. Associated morbidity was high at 57%, predominantly from cranial nerve palsy, and no deaths were encountered. Conclusions  Microsurgery is a suitable treatment for large symptomatic trigeminal schwannomas, achieving good local control rates over the observation period at acceptable morbidity. Therefore, microsurgery appears to a suitable option. During the study period, a significant evolution in the availability of treatment methods occurred. Radiosurgery emerged as an alternative treatment for unresectable lesions. A comprehensive review of the available literature was performed, and results were compared according to treatment modality.

Natural history of intraventricular meningiomas: systematic review

Review the data published on the subject to create a more comprehensive natural history of intraventricular meningiomas (IVMs). A Medline search up to March 2018 using "intraventricular meningioma" returned 98 papers. As a first selection step, we adopted the following inclusion criteria: series and case reports about IVMs, as well as papers written in other languages, but abstracts written in English were evaluated. Six hundred eighty-one tumors were evaluated from 98 papers. The majority of the tumors were located in the lateral ventricles (602-88.4%), fourth ventricle (59-8.7%), and third ventricle (20-2.9%). These tumors accounted for a mortality rate of 4.0% (25 deaths) and a recurrence rate of 5.3% (26 recurrences). The majority of the tumors were grade I (89.8%) and consisted of the following subtypes: fibrous, 39.7% (n = 171); transitional, 22.0% (n = 95); meningothelial, 18.6% (n = 80); angiomatosus, 3.2% (n = 14); psammomatous, 2.6% (n = 11); and others, 13.9% (n = 60). Forty-five patients (7.4%) presented with grade II (GII) tumors, and 17 patients (2.8%) presented with grade III (GIII) tumors. These tumors follow the histopathological distribution of meningiomas in general, with the exception of the higher prevalence of the fibrous subtype, possibly due to its embryonic origin. Recurrence and mortality were lower than in other localizations likely due to a complete surgical resection rate than in the convexity and skull base, which suggests that GTR is the gold standard for the management of IVMs.

Giant mucopyocele associated with intracranial hypertension: Case report and literature review

Background

Mucoceles are epithelial lined sacs that contain mucous. Eventually, they can be infected and so called mucopyoceles, which are usually slow growing lesions with common bone destruction located in the facial sinus. Mucoceles show multivariate etiology and occur between the fourth and seventh decade of life.

Case Description

Patient, 55-year-old, female, was referred unconscious with Cushing's triad to our department; she had fever since four days. The findings of skull computer tomography highlighted a large bifrontal lesion with an invasion of the rear wall of the frontal sinus, compression of the frontal lobes, and midline deviation. She was taken for an emergency surgery, which showed invasion of the dura and mucous infection. Postoperatively, there was a fast recovery of neurologic level and extubation on the second postoperative day. She took antibiotics for 14 days and was discharged from the hospital without neurologic deficits.

Conclusions

Mucopyoceles are usually slow growing lesions that rarely increases rapidly. Our patient presented signs of intracranial hypertension; therefore, it was necessary to have quick surgical intervention.

Spinal cord stimulation in the treatment of neuropathic pain: Current perspectives of indications, cost-effectiveness, complications and results

Introduction: The spinal cord stimulation (SCS) has been described as a valuable neuromodulating procedure in the management of chronic and medically untreated neuropathic pain. Although, many studies have discussed the use of this technique, a question still remains regarding its efficacy in different medical conditions with different etiology in the long term. The aim of this paper is to discuss the risks, complications, cost-effectiveness and results of SCS in patients affected by chronic neuropathic pain based on the comprehensive literature review. Methods: Bibliographic search of references from 1950 to 2016 using the databases MEDLINE, LILACS, SciELO, PubMed, and applied language as selection criteria, choosing preferably recent articles written in Portuguese, Spanish or English. Results: Based on literature review, SCS is a safe, reversible, adjustable and nondestructive surgical procedure demonstrating a significant effect in the reduction of pain intensity and improvement in quality of life in these patients. Furthermore, in spite of the initial high cost to its application, SCS has been associated with lower rates of complications and high rates of cost-effectiveness when compared to standard therapies. Conclusion: Although used in medical conditions with different etiology, the procedure is still an effective and a cost-effective approach to neuropathic pain, mainly in patients affected by failed back pain syndrome (FBSS) and complex regional pain syndrome (CRPS).

Middle cerebral artery aneurysms: aneurysm angiographic morphology and its relation to pre-operative and intra-operative rupture

ABSTRACT Objective Correlate the middle cerebral artery bifurcation aneurysm morphology with the pre-operative and intra-operative risk of rupture. Methods Forty patients with 46 middle cerebral artery bifurcation aneurysms were treated microsurgically by the same surgeon. Aneurysms were classified according to shape and the Fisher test was applied to analyze the effect of morphology on the pre-operative and intra-operative rupture. Results Pre-operative and intra-operative ruptures were observed in 8/46 patients (17.4%) and 14/46 patients (30.4%) respectively. Thirty-two cases (69.6%) had no symptoms postoperatively, modified Rankin score (MRS) of 0; 6.5% had MRS of 1 (no significant disability); 13% had MRS of 2 (slight disability); 4.3% had moderately severe disability (MRS of 4); and there were 3 deaths (6.5%) post-operatively. The morphology was not directly related to the rupture rate. Conclusion In general, ruptures are not affected by the morphology or the studied variables. Larger series are needed to validate these outcomes.

Abducent nerve palsy after microballoon compression of the trigeminal ganglion: Case report

Background:

Trigeminal neuralgia (TN) is the most common type of facial neuralgia with incidence of 26.8/100,000 person year. In general, this scenario is characterized by a lancinating, unilateral, paroxysmal pain in the area of the fifth cranial nerve. Several treatment methods, including the injection of ethyl alcohol or butyl alcohol into the ganglion, the glycerol injection into the trigeminal cistern, peripheral nerve divisions, the radiofrequency thermocoagulation of the preganglionic fibers, and radiosurgery has been used for TN.

Case Description:

A case of a 74-year-old woman patient who undergone a treatment of TN through a compression of Meckel cave and developed a transient abducent palsy is presented. Complication regarding to a palsy of abducent nerve is discussed as well as the analysis of presumable evolving physiopathology. A critical review of literature was performed.

Conclusions:

Among the procedures, we mean that percutaneous microballoon compression (PMC) is the best choice for elderly frail patients, because it had a very low associated mortality-morbidity rate and does not damage permanent the Gasserian ganglion.

Rare complication of ventriculoperitoneal shunt: Catheter protrusion to subcutaneous tissue - Case report

Background:

Ventriculoperitoneal (VP) shunt is a day-to-day procedure performed by a neurosurgeon. The most frequent associated complications are obstructive and infectious. Although rare, there are well-reported complications related to the poor positioning of the distal catheter, with perforation of organs and tissues. Still rarer are the complications related to the migration of this catheter.

Case Description:

We describe an atypical case of VP shunt postoperative by normal pressure hydrocephalus. After well-documented proper positioning of the distal catheter into the intraperitoneal cavity, it protruded into the subcutaneous space. Even on a new documented satisfactory abdominal tomography, this catheter migrated back again to the subcutaneous tissue.

Conclusion:

We did not find plausible explanation for this rare event.

"Next Door" intraoperative magnetic resonance imaging for awake craniotomy: Preliminary experience and technical note

BACKGROUND

During glioma surgery "maximal safe resection" must be the main goal. Intraoperative magnetic resonance imaging (iMRI) associated with awake craniotomy (AC) is a valuable tool to achieve this objective. In this article, AC with a "next-door" iMRI concept is described in a stepwise protocol.

METHODS

This is a retrospective analysis of 18 patients submitted to AC using iMRI; a stepwise protocol is also discussed.

RESULTS

The mean age was 41.7 years. Hemiparesis, aphasia, and seizures were the main initial symptoms of the patients. Sixty-six percent of the tumors were located in the left hemisphere. All tumors were near or within eloquent areas. Fifty-three percent of the cases were glioblastomas multiforme and 47% of the patients had low grade gliomas. The mean surgical time and iMRI time were 4 h 4 min and 30 min, respectively. New resection was performed in 33% after iMRI. Extent of resection (EOR) higher than 95% was possible in 66.7% of the patients. The main reason of EOR lower than 95% was positive mapping of eloquent areas (6 patients). Eighty percent of the patients experienced improvement of their deficits immediately after the surgery or had a stable clinical status whereas 20% had neurological deterioration, however, all of them improved after 30 days.

CONCLUSION

AC associated with "next-door" iMRI is a complex procedure, but if performed using a meticulous technique, it may improve the overall tumor resection and safety of the patients.

Proposed clinical internal carotid artery classification system

INTRODUCTION

Numerical classification systems for the internal carotid artery (ICA) are available, but modifications have added confusion to the numerical systems. Furthermore, previous classifications may not be applicable uniformly to microsurgical and endoscopic procedures. The purpose of this study was to develop a clinically useful classification system.

MATERIALS AND METHODS

We performed cadaver dissections of the ICA in 5 heads (10 sides) and evaluated 648 internal carotid arteries with computed tomography angiography. We identified specific anatomic landmarks to define the beginning and end of each ICA segment.

RESULTS

The ICA was classified into eight segments based on the cadaver and imaging findings: (1) Cervical segment; (2) cochlear segment (ascending segment of the ICA in the temporal bone) (relation of the start of this segment to the base of the styloid process: Above, 425 sides [80%]; below, 2 sides [0.4%]; at same level, 107 sides [20%]; P < 0.0001) (relation of cochlea to ICA: Posterior, 501 sides [85%]; posteromedial, 84 sides [14%]; P < 0.0001); (3) petrous segment (horizontal segment of ICA in the temporal bone) starting at the crossing of the eustachian tube superolateral to the ICA turn in all 10 samples; (4) Gasserian-Clival segment (ascending segment of ICA in the cavernous sinus) starting at the petrolingual ligament (PLL) (relation to vidian canal on imaging: At same level, 360 sides [63%]; below, 154 sides [27%]; above, 53 sides [9%]; P < 0.0001); in this segment, the ICA projected medially toward the clivus in 275 sides (52%) or parallel to the clivus with no deviation in 256 sides (48%; P < 0.0001); (5) sellar segment (medial loop of ICA in the cavernous sinus) starting at the takeoff of the meningeal hypophyseal trunk (ICA was medial into the sella in 271 cases [46%], lateral without touching the sella in 127 cases [23%], and abutting the sella in 182 cases [31%]; P < 0.0001); (6) sphenoid segment (lateral loop of ICA within the cavernous sinus) starting at the crossing of the fourth cranial nerve on the lateral aspect of the cavernous ICA and located directly lateral to the sphenoid sinus; (7) ring segment (ICA between the 2 dural rings) starting at the crossing of the third cranial nerve on the lateral aspect of the ICA; (8) cisternal segment starting at the distal dural ring.

CONCLUSIONS

The classification may be applied uniformly to all skull base surgical approaches including lateral microsurgical and ventral endoscopic approaches, obviating the need for 2 separate classification systems. The classification allows extrapolation of relevant clinical information because each named segment may indicate potential surgical risk to specific structures.

Giant pseudoaneurysm originated from distal middle cerebral artery dissection treated by trapping under sensitive evoked potential and motor evoked potential monitoring: Case report and discussion

BACKGROUND

Dissecting giant pseudoaneurysm of the middle cerebral artery (MCA) is a rare lesion often presenting challenges to neurosurgical teams dealing with this specific pathology. Giant pseudoaneurysm originating from a dissecting distal segment of the MCA treated with aneurysm trapping under motor and sensitive evoked potential monitoring with a successful outcome is presented in the article followed by a brief discussion on the subject.

CASE DESCRIPTION

A case of a previously healthy young female patient admitted at the emergency room of Santa Paula Hospital with a history of a sudden headache and syncope, dysphasia, and Grade 4 right hemiparesis due to a large brain hemorrhage secondary to a 25 mm ruptured pseudoaneurysm originated from a distal left MCA dissecting segment is described. Because the patient risked neurological worsening, aneurysm was treated with parent and efferent vessel trapping technique and no changes on the sensitive and motor evoked potential (MEP) from baseline informed on this decision. Hemorrhage was completely drained after aneurysm was secured.

CONCLUSION

Neurophysiological sensitive and MEP monitoring, on this specific case was a valuable tool and informed on the decision of trapping of this large vascular lesion.

Interfascial Dissection for Protection of the Nerve Branches to the Frontalis Muscles during Supraorbital Trans-Eyebrow Approach: An Anatomical Study and Technical Note

Introduction Preservation of the temporal branches of the facial nerve during anterolateral craniotomies is important. Damaging it can inflict undesirable cosmetic defects to the patient. The supraorbital trans-eyebrow approach (SOTE) is a versatile keyhole craniotomy but still has a high rate of frontalis muscle (FM) palsy. Objective Anatomical study to implement the interfascial dissection during the SOTE to preserve the nerves to the FM. Methods Slight modification of the standard technique of the SOTE was performed in 6 cadaveric specimens (12 sides). Results Distal rami to the FM were exposed. The standard "u-shape" incision of the FM can cross over the nerves. Alternatively, an "l-shape" incision was performed until the superior temporal line (STL). An interfascial dissection was performed near to the STL and the interfascial fat pad was used as a protective layer for the nerves. Conclusion Various pathologies can be addressed with the SOTE. In the majority of the cases the cosmetic results are good, but FM palsy remains a drawback of this approach. The interfascial dissection may be used in an attempt to prevent frontalis rami palsy.

Volumetry and analysis of anatomical variants of the anterior portion of the petrous apex outlined by the kawase triangle using computed tomography

Background Anterior petrosectomy has become an increasingly used approach for petroclival lesions. This study measures the volume and the anatomical variants of the anterior portion of the petrous apex outlined by the Kawase triangle using computed tomography (CT). Methods This was a transversal retrospective study. We assessed the anterior petrous apex portion outlined by the Kawase triangle in consecutive patients > 18 years of age from CT scans of temporal bone stored in an archive system. The volumetry was performed on a workstation. Results A total of 154 petrosal apex were analyzed in 77 patients (36 men). The average volume of the region outlined by the Kawase triangle was 1.89 ± 0.52 cm(3). The volume average in men was 2.01 ± 0.58 cm(3), and the average in women was 1.79 ± 0.41 cm(3). Intra- and interobserver agreement were both excellent, and there was little variance. Nineteen petrous apex demonstrated anatomical variations. In 18 cases it was pneumatized, and in one case a vascular or nerve-like structure was identified, a report we did not find in the literature. Conclusion The volumetry of the petrous apex anterior portion outlined by the Kawase triangle can be made by CT with excellent intra- and interobserver agreement and reproducibility. There are anatomical variants in this region that are relevant to surgery.

Endoscopic anatomy of sellar region

The transsphenoidal approach is the preferred access used in surgical treatment of most sellar region pathologies. The use of endoscopy is advantageous, and it is considered a good alternative to the traditional microsurgical technique. The purpose of this study is to recognize and describe anatomical variations of the sphenoid sinus and the sellar region, mainly describing the anatomy of the posterior wall of the sphenoid sinus and analyzing intercarotid distances in 3 regions. Thirty sphenoid blocks treated with formaldehyde were injected and dissected. Using endoscopy, anatomical variations were studied and the intercarotid distances were measured at the tuberculum sellae, sellar floor and clivus. The types of sphenoid sinus found were: conchal in 1 (4.76 %), pré-sellar in 2 (9.52 %) and sellar in 19 (85.7 %) specimens. The mean distance found from the sphenoid sinus ostium to the sella turcica was 19 mm (±6.5) mm. The mean intercarotid distances found at the tuberculum sellae, sellar floor and clivus were respectively 13.32, 18.00 and 18.90 mm. Endoscopy, with its magnification and lighting provide a panoramic view of deep fields. The anatomical variations described in this study support the need for a careful evaluation of preoperative images in each case.

Brainstem cavernomas: a surgical challenge

OBJECTIVE

The authors show their experience with brainstem cavernomas, comparing their data with the ones of a literature review.

METHODS

From 1998 to 2009, 13 patients harboring brainstem cavernomas underwent surgical resection. All plain films, medical records and images were reviewed in order to sample the most important data regarding epidemiology, clinical picture, radiological findings and surgical outcomes, as well as main complications.

RESULTS

The mean age was 42.4 years (ranging from 19 to 70). No predominant gender: male-to-female ratio, 6:7. Pontine cases were more frequent. Magnetic resonance imaging was used as the imaging method to diagnose cavernomas in all cases. The mean follow-up was 71.3 months (range of 1 to 138 months). Clinical presentation was a single cranial nerve deficit, VIII paresis, tinnitus and hearing loss (69.2%). All 13 patients underwent resection of the symptomatic brainstem cavernoma. Complete removal was accomplished in 11 patients. Morbidity and mortality were 15.3 and 7.6%, respectively.

CONCLUSIONS

Cavernomas can be resected safely with optimal surgical approach (feasible entry zone) and microsurgical techniques, and the goal is to remove all lesions with no cranial nerves impairment.

Quantitative ventricular neuroendoscopy performed on the third ventriculostomy: anatomic study

BACKGROUND

One of the key elements for a successful endoscopic intervention in the ventricular system is the ability to recognize the anatomic structures and use them as a reference.

OBJECTIVE

To measure the choroid plexus with endoscopy in the interventricular foramen, together with the structures on the third ventricle floor, and to compare these variables.

METHODS

An observational prospective study was carried out on 37 brains of cadavers for which the cause of death was assessed at the Death Check Unit of the University of São Paulo in April 2008. This study was done on adults of both sexes with a rigid neuroendoscope. Endoscopic images were recorded, submitted for correction of distortion, and then measured.

RESULTS

The measurements of the choroid plexus in the interventricular foramen, laterolateral distance of mammillary bodies, distance from the infundibular recess to the mammillary bodies, and area of the triangle in the tuber cinereum were 1.71 ± 0.77 mm, 2.23 ± 0.74 mm, 3.22 ± 0.82 mm, and 3.69 ± 2.09 mm, respectively. The ventricle floor was opaque in 84% of cases. The internal distance of mammillary bodies was absent in 89%. Associations between the translucent floor of the third ventricle and laterolateral distance of mammillary bodies, internal distance of mammillary bodies, and age were identified.

CONCLUSION

Before this research, there was no record of the measurements of the choroid plexus in the interventricular foramen. The remaining variables of the present study show a greater number in normal brains compared with others.

Anatomia microcirúrgica das artérias infratentoriais: um estudo estereoscópico

CONTEXTO: O espaço infratentorial do crânio é uma região que possui complexa rede de artérias que vascularizam o tecido cerebelar e o tronco encefálico. Sua complexa anatomia tridimensional deve ser profundamente entendida pelo neurocirurgião vascular e pelo radiologista intervencionista. OBJETIVO: Descrever as principais artérias do espaço infratentorial e seu trajeto, bem como sua relação com a topografia das estruturas neurais. MÉTODOS: Foram estudados 30 cérebros humanos, fixados em formalina e 6 cabeças de cadáveres dissecadas, utilizando-se microscópico cirúrgico com 3X a 40X de aumento. Os cérebros e todas as cabeças foram injetados com siloxanos polimerizados ou polisiloxanos (silicone) colorido. As dissecções anatômicas foram documentadas utilizando-se técnica para obtenção de imagens tridimensionais (3D), objetivando a produção de impressões estereoscópicas. RESULTADOS: São descritos o trajeto, segmentos e ramos das artérias basilar, cerebelar superior, cerebelar anteroinferior, cerebelar posteroinferior e vertebral. CONCLUSÃO: A anatomia das artérias infratentoriais é complexa e as imagens estereoscópicas apresentadas são um importante instrumento de documentação, pois permitem uma noção de profundidade da anatomia estudada.