Single-Base Gene Variants in MIR-146A and SCN1A Genes Related to the Epileptogenic Process in Drug-Responsive and Drug-Resistant Temporal Lobe Epilepsy-A Preliminary Study in a Brazilian Cohort Sample.

The drug-resistant temporal lobe epilepsy (TLE) has recently been associated with single nucleotide variants (SNVs) in microRNA(miR)-146a (MIR-146A) (rs2910164) and Sodium Voltage-Gated Channel Alpha Subunit 1 (SCN1A) (rs2298771 and rs3812718) genes. Moreover, no studies have shown an association between these SNVs and susceptibility to drug-resistant and drug-responsive TLE in Brazil. Thus, deoxyribonucleic acid (DNA) samples from 120 patients with TLE (55 drug-responsive and 65 drug-resistant) were evaluated by real-time polymerase chain reaction (RT-PCR). A total of 1171 healthy blood donor individuals from the Online Archive of Brazilian Mutations (ABraOM, from Portuguese Arquivo Brasileiro On-line de Mutações), a repository containing genomic variants of the Brazilian population, were added as a control population for the studied SNVs. MIR-146A and SCN1A relative expression was performed by quantitative RT-PCR (qRT-PCR). The statistical analysis protocol was performed using an alpha error of 0.05. TLE patient samples and ABraOM control samples were in Hardy-Weinberg equilibrium for all studied SNVs. For rs2910164, the frequencies of the homozygous genotype (CC) (15.00% vs. 9.65%) and C allele (37.80% vs. 29.97%) were superior in patients with TLE compared to controls with a higher risk for TLE disease [odds ratio (OR) = 1.89 (95% confidence interval (95%CI) = 1.06-3.37); OR = 1.38 (95%CI = 1.04-1.82), respectively]. Drug-responsive patients also presented higher frequencies of the CC genotype [21.81% vs. 9.65%; OR = 2.58 (95%CI = 1.25-5.30)] and C allele [39.09% vs. 29.97%; OR = 1.50 (95%CI = 1.01-2.22)] compared to controls. For rs2298771, the frequency of the heterozygous genotype (AG) (51.67% vs. 40.40%) was superior in patients with TLE compared to controls with a higher risk for TLE disease [OR = 2.42 (95%CI = 1.08-5.41)]. Drug-resistant patients presented a higher AG frequency [56.92% vs. 40.40%; OR = 3.36 (95%CI = 1.04-17.30)] compared to the control group. For rs3812718, the prevalence of genotypes and alleles were similar in both studied groups. The MIR-146A relative expression level was lower in drug-resistant compared to drug-responsive patients for GC (1.6 vs. 0.1, p-value = 0.049) and CC (1.8 vs. 0.6, p-value = 0.039). Also, the SCN1A relative expression levels in samples from TLE patients were significantly higher in AG [2.09 vs. 1.10, p-value = 0.038] and GG (3.19 vs. 1.10, p-value < 0.001) compared to the AA genotype. In conclusion, the rs2910164-CC and rs2298771-AG genotypes are exerting significant risk influence, respectively, on responsive disease and resistant disease, probably due to an upregulated nuclear factor kappa B (NF-kB) and SCN1A loss of function.

Primary central nervous system lymphoma in a patient with multiple sclerosis using fingolimod.

Primary central nervous system lymphoma (PCNSL) is an uncommon lymphoproliferative disease associated with immunosuppression. Here, we report the case of a patient with multiple sclerosis, under treatment with fingolimod (FTY720, Gilenya) for 4 years, who developed this condition. Although the causal relationship cannot be established, there are cases in the literature that describe the appearance of lymphoma after the use of this medication. Considering the high mortality of PCNSL, epidemiological studies are necessary to establish a relationship between its arising and the use of immunosuppressants.

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.

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.

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.

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.

Prospective factors of temporary arterial occlusion during anterior communicating artery aneurysm repair.

INTRODUCTION: This study was undertaken to determine variables that could predict, in the perioperative period of anterior communicating artery (ACom) aneurysms surgeries, the likelihood of postoperative sequelae and complications, after temporary arterial occlusion (TAO). PATIENTS AND METHODS: In a universe of 32 patients submitted to ACom aneurysm repair in the last 7 years, 21 needed TAO intraoperatively, and had their data examined retrospectively. RESULTS: Aneurysms larger than 7 mm were more likely to be treated with longer TAO time than small aneurysms, (p < 0.0001). There was no statistical correlation between time of occlusion and outcome. Age, Glasgow Coma Scale at initial evaluation, and Fisher scale at first CT scanning were independent factors of unfavorable outcome (p < 0.001). Meanwhile gender, tobacco addiction, obesity, arterial hypertension, dyslipidemia, location of TAO (A1 or A2), intraoperative rupture (IR) and the aneurysm size were not identified as independent prognostic factors.During follow-up period, two thirds of the patients had a favorable outcome, accomplishing normal daily life activities without major complications. Most patients developed clinical vasospasm (66.6 %), with 19 % of the patients harboring a severe disease. Delayed ischemic neurological deficit was observed in 28.5 %, without any statistical correlation to time of TAO or IR. CONCLUSION: TAO during ACom aneurysm repair does not seem to add more morbidities to the procedure, and is not an independent prognostic factor.

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.

Effectiveness of C5 or C6-Cz assembly in predicting immediate post operative facial nerve deficit.

BACKGROUND: Intraoperative neurophysiology monitoring (IOM) is a valuable tool in cerebellopontine angle (CPA) surgeries posing risk to the cranial nerves. Transcranial electrical stimulation (TES) for cranial nerves has been performed in the last 7 years, for obtaining the facial nerve motor evoked potential (MEP), using either C3/C4-Cz or C3-C4 (or inverse) stimulating points, which have been correlated with facial nerve functional outcome. METHOD: Intraoperative surgical and electrophysiological findings were documented prospectively. Patient files were reviewed for clinical data. We studied 23 patients undergoing CPA tumor resection using C5 or C6-Cz montage for TES, and were able to determine the correlation between facial nerve functional outcome and the amplitude drop of facial MEP above 50 %. Patients were evaluated for immediate facial nerve outcome and 6 months after the surgery. Follow-up was performed by structured telephone interviews with local physicians. RESULTS: The sensibility of the studied parameters was 92.8 % for amplitude drop of facial nerve MEP, with positive predictive value of 81.2 %. The absence of changes during IOM has shown a negative predictive value of 100 %. CONCLUSION: In this series, the used montage was effective in predicting new facial deficit.

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.

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.

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.

Comparison between the C5 or C6-Cz electrode assembly and C3 or C4-Cz assembly for transcranial electric motor activation of muscular response of the contralateral facial nerve.

OBJECTIVE: We used an assembly of electrodes C3 and C4-Cz in order to activate the motor cortical area of the corticobulbar tract to elucidate the motor-evoked potential of the contralateral mentalis muscle. METHOD: We compared this setup to that of an assembly with electrodes C5 or C6-Cz using a train of electrical pulses and a single electrical pulse. This analysis was made in 23 consecutive patients who underwent several varied surgeries and were prospectively operated on at Santa Paula Hospital between January and June 2011. RESULTS: The results showed that the assembly with C5 or C6-Cz produced a multisynaptic motor-evoked potential in the contralateral mentalis muscle in 86.9 % of the patients, whereas 82.6 % of patients stimulated at points C3 or C4-Cz presented the same response. However, both assemblies showed similar behavior with the use of a single electrical pulse for peripheral contralateral nerve stimulation. CONCLUSION: We concluded that the C5 or C6-Cz assembly was similar to C3 or C4-Cz in obtaining a multisynaptic response in the contralateral mentalis muscle, although it required less intensive stimulation than the C3 or C4- Cz assembly.

What is the ideal grade of resection for parasagittal meningiomas with the invasion of superior sagittal sinus? Simpson I or Simpson II resection? A retrospective observational study.

Background: Parasagittal meningioma (PSM) is a tumor located in the parasagittal angle which extends to and/ or invades the superior sagittal sinus (SSS). Surgical resection of the PSM, the standard treatment in such cases, poses a challenge for neurosurgery, particularly where there is an invasion of the SSS. This is due to the risk of complications through injury to the adjacent vascular structures. The objective of the study was to perform a comparative evaluation of the surgical techniques for total resection of the PSM (Simpson Grade [SG] I and SG II), which present the highest rates of success in terms of the following variables: mortality, recurrence, and postoperative complications. Methods: Fifty-six patients undergoing resection surgery for PSM with the invasion of the SSS were enrolled. The patients were divided into two groups: Group A, comprising 26 cases of patients subjected to SG I PSM resection surgery and Group B, with 31 cases of patients subjected to SG II PSM resection surgery, with preservation of the SSS. Results: The results showed that Group B had lower rates of postoperative deficit (P = 0.026), zero mortality, and reduced recurrence. The use of complementary radiotherapy for atypical meningiomas (WHO II) in Group B was satisfactory in controlling the disease. Conclusion: The Simpson II, with preservation of the SSS, was better as it diminishes the vascular risks of surgery, reduces the frequency of severe postoperative deficit, and reduces mortality.

[Surgical approaches to petroclival meningiomas Part 2: narrative review of what we learned with 30 cases]. / Abordajes quirúrgicos de los meningiomas petroclivales Parte 2: revisión narrativa y lo que aprendimos con 30 casos.

Background: The surgical ressection of petroclival meningiomas is challenging due to its deep location and relationship with vital neurovascular structures. Usually they are benign injuries, but they can involve or infiltrate skull base bones, dura mater and brainstem. This makes the total removing very difficult or impossible without causing neurological deficits. The objective of this study is to review the surgical approaches used on the treatment of petroclival meningiomas and the knowledge which we achieved upon the surgical management of 30 cases. Methods: Series of 30 petroclival meningioma-cases. In the beginning of our series we used petrous approach for all the cases, however, with the acquiring of experience, we are indicating the retrosigmoid approach, leaving the petrous and skull-orbito-zigomatics approaches for selected cases. Results: Owing to the difficulty of the access, the petroclival meningiomas usually require different surgical approaches and have distint surgical difficulties. There are three main approaches: fronto-orbito-zigomatics and variants; petrous and variants and retrosigmoid, and they can be combined. The choice for a surgical approach is usually on the location and size of the tumor, on the skull shape, the involvement of venous structures and according to the surgeon´s experience. Conclusion: Petroclival meningiomas are rare and complex on the skull base. The adequate choice is crucial to achieve the good surgical result.

[Surgical Approaches to Petroclival Meningiomas Part 1: Microsurgical Anatomy]. / Abordajes quirúrgicos de meningiomas petroclivales parte 1: anatomía microquirúrgica.

Background: Most petroclival meningiomas are benign tumors, but their neurosurgical treatment is one of the greatest challenges in this field. Acquiring a deep practical knowledge of brain anatomy is the first step on the path to successfully meeting this challenge. To this end, the present paper is divided into two parts. The first regards the microsurgical anatomy and surgical approaches used in the management of petroclival meningiomas. The second correlates the brain anatomies of the 30 cases of petroclival meningiomas which the senior author (GRI) has operated on. Methods: Eight cadaver heads were dissected using surgical microscopes at the University of Arkansas microsurgery laboratory. The heads were stabilized in a Mayfield device to simulate surgical conditions and colored silicon was injected to highlight the differences between arteries and veins. The approaches performed were: cranio-orbital zygomatic, posterior and anterior petrosectomy, and retrosigmoid. Results: Three main surgical approaches were chosen to treat petroclival meningiomas: the pterional approach and its variants, the petrous approach and its variants, and the retrosigmoid approach. To rationalize the choice of approach, the clivus was separated into superior, middle, and inferior thirds. Conclusion: Several surgical approaches are useful in accessing the petroclival region. Acquiring a practical knowledge of this anatomy in a microsurgical laboratory is fundamental for any surgeon who intends to operate on petroclival meningiomas.

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.

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).

Surgical management of brainstem cavernous malformations.

Bleeding from brainstem cavernomas may cause severe deficits due to the absence of non-eloquent nervous tissue and the presence of several ascending and descending white matter tracts and nerve nuclei. Surgical removal of these lesions presents a challenge to the most surgeons. The authors present their experience with the surgical treatment of 43 patients with brainstem cavernomas. Important aspects of microsurgical anatomy are reviewed. The surgical management, with special focus on new intraoperative technologies as well as controversies on indications and timing of surgery are presented. According to several published studies the outcome of brainstem cavernomas treated conservatively is poor. In our experience, surgical resection remains the treatment of choice if there was previous hemorrhage and the lesion reaches the surface of brainstem. These procedures should be performed by experienced neurosurgeons in referral centers employing all the currently available technology.