Anatomy of the posterior Fossa: a comprehensive description for pediatric brain tumors.

Posterior fossa tumors are the most common pediatric brain tumors, and present unique challenges in terms of their location and surgical management. The posterior fossa comprehends complex anatomy and represents the smallest and deepest of the three cranial base fossae. An in-depth understanding of posterior fossa anatomy is crucial when it comes to the surgical resection of pediatric brain tumors. Mastering the knowledge of posterior fossa anatomy helps the neurosurgeon in achieving a maximal and safe volumetric resection, that impacts in both overall and progression free survival. With the advancements in microsurgery, the telovelar approach has emerged as the workhorse technique for the resection of posterior fossa tumors in pediatric patients. This approach involves meticulously dissecting of the natural clefts present in the cerebellomedullary fissure, making a comprehensive understanding of the underlying anatomy key for its success.

Performance of intraoperative neurocognitive tests during awake surgery for patients with diffuse low-grade glioma.

Despite great advancements and the diffusion of awake surgery for brain tumors, the literature shows that the tests applied during the procedure are heterogeneous and non-standardized. This prospective, observational, descriptive study collected data on intraoperative brain mapping and the performance of multiple neurocognitive tests in 51 awake surgeries for diffuse low-grade glioma. Frequency of use and rate of intraoperative findings of different neurocognitive tests were analyzed. Patients mean age at the time of surgery was 35.1 (20-57) years. We performed 26 (51.0%) surgeries on the left hemisphere (LH) and 25 (49.0%) on the right hemisphere (RH). Significant differences were observed between the total number of functional findings (cortical and subcortical) identified in the LH and RH (p = 0.004). In subcortical findings alone, the differences remained significant (p = 0.0004). The RH subcortical region showed the lowest number of intraoperative findings, and this was correlated with functional outcome: Karnofsky performance scale at five days (p = 0.022), three months (p = 0.002) and one year (p = 0.002) post-surgery. On average, more tests were used to map the RH, with a lower frequency of both cortical and subcortical functional findings. Even though subcortical findings were less frequent than cortical findings, they were crucial to defining the resection margins. Based on the intraoperative findings, frequency of use, and rate of findings per use of the tests analyzed, the most relevant tests for each hemisphere for awake brain mapping were identified.

Posterior fossa tumors in children: current insights.

While in adults most intracranial tumors develop around the cerebral hemispheres, 45 to 60% of pediatric lesions are found in the posterior fossa, although this anatomical region represents only 10% of the intracranial volume. The latest edition of the WHO classification for CNS tumors presented some fundamental paradigm shifts that particularly affected the classification of pediatric tumors, also influencing those that affect posterior fossa. Molecular biomarkers play an important role in the diagnosis, prognosis, and treatment of childhood posterior fossa tumors and can be used to predict patient outcomes and response to treatment and monitor its effectiveness. Although genetic studies have identified several posterior fossa tumor types, differing in terms of their location, cell of origin, genetic mechanisms, and clinical behavior, recent management strategies still depend on uniform approaches, mainly based on the extent of resection. However, significant progress has been made in guiding therapy decisions with biological or molecular stratification criteria and utilizing molecularly targeted treatments that address specific tumor biological characteristics. The primary focus of this review is on the latest advances in the diagnosis and treatment of common subtypes of posterior fossa tumors in children, as well as potential therapeutic approaches in the future.   Conclusion: Molecular biomarkers play a central role, not only in the diagnosis and prognosis of posterior fossa tumors in children but also in customizing treatment plans. They anticipate patient outcomes, measure treatment responses, and assess therapeutic effectiveness. Advances in neuroimaging and treatment have significantly enhanced outcomes for children with these tumors. What is Known: • Central nervous system tumors are the most common solid neoplasms in children and adolescents, with approximately 45 to 60% of them located in the posterior fossa. • Multimodal approaches that include neurosurgery, radiation therapy, and chemotherapy are typically used to manage childhood posterior fossa tumors What is New: • Notable progress has been achieved in the diagnosis, categorization and management of posterior fossa tumors in children, leading to improvement in survival and quality of life.

Growing skull fracture in a child with Ehlers-Danlos syndrome: case report and literature review.

INTRODUCTION: Growing skull fracture (GSF) is a rare complication of head trauma in the pediatric population, commonly observed in children younger than 3 years. DISCUSSION: In this report, the authors describe a case of a 3-year-old male child, with clinical features of Ehlers-Danlos syndrome (EDS), who developed a GSF in frontal bone after a crib fall, treated with duraplasty and cranioplasty with autologous craft. Here, pertinent literature was reviewed with an emphasis on surgical techniques, and correlation with the mentioned syndrome. CONCLUSION: This is the first case of GSF in association with EDS in the literature. The relevance of the case described concerns the rarity of the condition itself, the atypical presentation, and the intraoperative findings, which showed the important fragility of the dura mater, probably due to EDS. Therefore, this syndrome, besides having influenced the pathogenesis, was also a challenging factor in the surgical treatment.

Peritoneal metastasis of a brainstem anaplastic ganglioglioma in a 2-year-old boy: case report and literature review.

Anaplastic gangliogliomas (AGG) are rare tumors of the central nervous system (CNS) that commonly affect children and young adults, with an unusual infratentorial presentation, which is related to hydrocephalus and a worse prognosis. We report a case of a brainstem AGG in a 2-year-old boy who underwent a ventriculoperitoneal shunting (VPS) and later presented peritoneal metastasis. We also reviewed the related literature. Even though rare, disease dissemination through VPS should be sought in patients with CNS tumors and VPS who develop new abdominal symptoms. The early diagnosis and intervention may minimize morbidity and improve quality of life of such patients.

Vertebral augmentation plus short-segment fixation versus vertebral augmentation alone in Kümmell's disease: a systematic review and meta-analysis.

Osteoporotic vertebral compression fractures of the thoracolumbar spine can progress to Kümmell's disease, an avascular vertebral osteonecrosis. Vertebral augmentation (VA)-vertebroplasty and/or kyphoplasty-is the main treatment modality, but additional short-segment fixation (SSF) has been recommended concomitant to VA. The aim is to compare clinical and radiological outcomes of VA + SSF versus VA alone. Systematic review, including comparative articles in Kümmell's disease, was performed. This study assessed the following outcome measurements: visual analog scale (VAS), Oswestry Disability Index (ODI), anterior vertebral height (AVH), local kyphotic angle (LKA), operative time, blood loss, length of stay, and cement leakage. Six retrospective studies were included, with 126 patients in the VA + SSF group and 152 in VA alone. Pooled analysis showed the following: VAS, non-significant difference favoring VA + SSF: MD -0.61, 95% CI (-1.44, 0.23), I2 91%, p = 0.15; ODI, non-significant difference favoring VA + SSF: MD -9.85, 95% CI (-19.63, -0.07), I2 96%, p = 0.05; AVH, VA + SSF had a non-significant difference over VA alone: MD -3.21 mm, 95% CI (-7.55, 1.14), I2 92%, p = 0.15; LKA, non-significant difference favoring VA + SSF: MD -0.85°, 95% CI (-5.10, 3.40), I2 95%, p = 0.70. There were higher operative time, blood loss, and hospital length of stay for VA + SSF (p < 0.05), but with lower cement leakage (p < 0.05). VA + SFF and VA alone are effective treatment modalities in Kümmell's disease. VA + SSF may provide superior long-term results in clinical and radiological outcomes but required a longer length of stay.

The surgical treatment of subaxial acute cervical spine facet dislocations in adults: a systematic review and meta-analysis.

Adult cervical spine traumatic facet joint dislocations occur when excessive traumatic forces displace the vertebrae's facets, leading to loss of joint congruence. Reduction requires either cranial traction or open surgical procedures. This study aims to appraise the effects of different surgical techniques in the treatment of subaxial cervical spine acute traumatic facet blocks in adults. This study was based on a systematic literature review and meta-analysis, registered in Prospero (CRD42021279249). The PICO question was composed of adults with acute cervical spine traumatic facet dislocations submitted to anterior or posterior surgical approaches, associated or not with cranial traction for reduction. Each surgical technique was compared to the other. The primary clinical outcomes included neurological improvement or worsening and surgical success/failure rates. The anterior approach without cranial traction was efficient in reducing facet displacements. Skull traction was an efficient and immediate method to achieve spine dislocation reductions. Differences were not present among techniques regarding neurological improvement. There were no surgical failures in patients operated on via the posterior approach. The need to decompress and stabilize the cervical spine can be achieved by anterior or posterior surgical approaches, and there is no clear answer as to which initial approach is superior to the other.

The impact of traumatic herniated discs in cervical facets dislocations treatments: systematic review and meta-analysis.

BACKGROUND: Traumatic facet dislocations in the subaxial cervical spine, also known as locked facets, are commonly associated with neurological deficits. The fear of the presence of an associated traumatic disc herniation and consequent neurological worsening usually causes a delay in the spinal realignment. This study's aim is an analysis of safety and efficacy when treating acute cervical traumatic facet dislocations using cranial-cervical traction or posterior open reduction and fixation in the presence of disc herniations. METHODS: Inclusion criteria addressed the following patient groups: (1) MRI diagnosis of traumatic cervical facet dislocations with disc herniation, (2) intervention: either cranial-cervical traction or posterior open reduction and fixation, (4) neurological outcomes after treatment, (5) adult 18 plus years of age, (6) sample sizes greater than 20 patients, (7) English language publication. The following databases and search tools were analyzed: MEDLINE (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), Google Scholar, and the clinical trial registries (ClinicalTrials.gov), October 2021. RESULTS: Six studies were found, 2 with posterior open reduction and fixation and 4 with cranial-cervical traction, totalizing 197 patients. Neurological worsening was reported only in 1 case (0.5%). CONCLUSIONS: Traumatic disc herniation in cervical facet dislocations is not an absolute contraindication of cranial-cervical traction or posterior open reduction. Early realignment of the spine could bring more neurological benefits than waiting for an MRI or surgical discectomy. However, caution is needed in this review's data interpretation until prospective and well-designed studies are performed.

Extent of resection in diffuse low-grade gliomas and the role of tumor molecular signature-a systematic review of the literature.

There is a lack of class I evidence concerning the impact of surgery in the treatment of diffuse low-grade glioma; the early maximal resection with preservation of eloquent brain areas has been accepted as the first therapeutic option. We performed a systematic review of the literature using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and protocol. Inclusion criteria: only case series with at least 100 patients containing supratentorial hemispheric diffuse low-grade glioma (according to any of the WHO classification used in papers published between 2000 to 2019), with pre- and postoperative MRI study were included in the qualitative and quantitative analyses. The extent of resection should be defined based on MRI at least in two categories and correlated with patients' outcomes (with univariate or multivariate analyses) using overall survival (OS) or malignant progression-free survival (MPFS). A total of 18 series with 4386 patients, published in 20 papers, were included in this systematic review. All the series that evaluates the relation between the extent of resection (EOR) and OS showed a statistically significant improvement of OS at univariate and/or multivariate analyzes with a greater EOR. Six studies showed a statistically significant improvement of MPFS with a greater EOR. We demonstrate that when a more rigorous analysis of EOR is performed, a benefit of a more aggressive resection on OS and MPFS is observed. Our review about EOR in different molecular groups of DLGG also suggests a benefit of maximum safe resection for all different subtypes, even though "radical surgery" may be associated with better OS and MPFS in tumors with a more aggressive signature.

Intracranial hypertension in patients with aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis.

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating and life-threatening condition with high mortality and morbidity. Even though there is an association with intracranial pressure (ICP) raise and aSAH, there is a lack of recommendations regarding the indications for ICP monitoring in patients with aSAH. Defining what patients are at a higher risk to develop intracranial hypertension and its role in the functional outcome and mortality in patients with aSAH will be the purpose of the following systematic review and meta-analysis. The primary endpoint is to determine the prevalence and impact on mortality of ICP in patients with aSAH. Secondary endpoints aim to describe the variables related to the development of ICP and the relationship between traumatic and aneurysmal etiology of intracranial hypertension. PubMed, Embase, Central Cochrane Registry of Controlled Trials, and research meeting abstracts were searched up to August 2019 for studies that performed ICP monitoring, assessed the prevalence of intracranial hypertension and the mortality, in adults. Newcastle Ottawa scale (NOS) was used to assess study quality. The statistical analysis was performed using the Mantel-Haenszel methodology for the prevalence and mortality of intracranial hypertension for reasons with a randomized effect analysis model. Heterogeneity was assessed by I2. A total of 110 bibliographic citations were identified, 20 were considered potentially eligible, and after a review of the full text, 12 studies were considered eligible and 5 met the inclusion criteria for this review. One study obtained 7 points in the NOS, another obtained 6 points, and the rest obtained 5 points. Five studies were chosen for the final analysis, involving 793 patients. The rate of intracranial hypertension secondary to aSAH was 70.69% (95% CI 56.79-82.84%) showing high heterogeneity (I2 = 92.48%, p = < 0.0001). The results of the meta-analysis of mortality rate associated with intracranial hypertension after aSAH found a total of four studies, which involved 385 patients. The mortality rate was 30.3% (95% CI: 14.79-48.57%). Heterogeneity was statistically significant (I2 = 90.36%; p value for heterogeneity < 0.001). We found that in several studies, they reported that a high degree of clinical severity scale (Hunt and Hess or WNFS) and tomographic (Fisher) were significantly correlated with the increase in ICP above 20 mmHg (P < 0.05). The interpretation of the results could be underestimated for the design heterogeneity of the included studies. New protocols establishing the indications for ICP monitoring in aSAH are needed. Given the high heterogeneity of the studies included, we cannot provide clinical recommendations regarding this issue.

Accuracy and reliability of the AO Spine subaxial cervical spine classification system grading subaxial cervical facet injury morphology.

PURPOSE: A classification system was recently developed by the international association AO Spine for assessing subaxial cervical spine fractures. Significant variability exists between users of the facet component, which consists of four morphological types (F1-F4). The primary aims of this study were to assess the diagnostic accuracy and reliability of this new system's facet injury morphological classifications. METHODS: A survey consisting of 16 computed tomography (CT) scans of patients with cervical facet fractures was distributed to spine surgeon members of AO Spine Latin America. To provide a gold standard diagnosis for comparison, all 16 injuries had been classified previously by six co-authors and only were included after total consensus was achieved. Demographic and surgical practice characteristics of all respondents were analyzed, and diagnostic accuracy calculated. Inter- and intra-observer agreement rates were calculated across two survey rounds, conducted one month apart. RESULTS: A total of 135 surgeons completed both surveys, among whom the mean age was 41.6 years (range 26-71), 130 (96.3%) were men, and 83 (61.5%) were orthopedic surgeons. The mean time in practice as a spine surgeon was 9.7 years (1-30). The overall diagnostic accuracy of all responses was 65.4%. Inter-observer and intra-observer agreement rates for F1/F2/F3/F4 were 55.4%/47.6%/64.0%/94.7% and 60.0%/49.1%/58.0%/93.0%, respectively. CONCLUSION: This study evaluates the AO Spine Classification System specifically for facet injuries involving the subaxial cervical spine in a large sample of spine surgeons. There was significant variability in diagnostic accuracy for F1 through F3-type fractures, whereas almost universal agreement was achieved for F4-type injuries.

Variation in global treatment for subaxial cervical spine isolated unilateral facet fractures.

PURPOSE: To determine the variation in the global treatment practices for subaxial unilateral cervical spine facet fractures based on surgeon experience, practice setting, and surgical subspecialty. METHODS: A survey was sent to 272 members of the AO Spine Subaxial Injury Classification System Validation Group worldwide. Questions surveyed surgeon preferences with regard to diagnostic work-up and treatment of fracture types F1-F3, according to the AO Spine Subaxial Cervical Spine Injury Classification System, with various associated neurologic injuries. RESULTS: A total of 161 responses were received. Academic surgeons use the facet portion of the AO Spine classification system less frequently (61.6%) compared to hospital-employed and private practice surgeons (81.1% and 81.8%, respectively) (p = 0.029). The overall consensus was in favor of operative treatment for any facet fracture with radicular symptoms (N2) and for any fractures categorized as F2N2 and above. For F3N0 fractures, significantly less surgeons from Africa/Asia/Middle East (49%) and Europe (59.2%) chose operative treatment than from North/Latin/South America (74.1%) (p = 0.025). For F3N1 fractures, significantly less surgeons from Africa/Asia/Middle East (52%) and Europe (63.3%) recommended operative treatment than from North/Latin/South America (84.5%) (p = 0.001). More than 95% of surgeons included CT in their work-up of facet fractures, regardless of the type. No statistically significant differences were seen in the need for MRI to decide treatment. CONCLUSION: Considerable agreement exists between surgeon preferences with regard to unilateral facet fracture management with few exceptions. F2N2 fracture subtypes and subtypes with radiculopathy (N2) appear to be the threshold for operative treatment.

Hemoglobin levels as a transfusion criterion in moderate to severe traumatic brain injury: a systematic review and meta-analysis.

BACKGROUND: Several factors can influence the outcome of severe head injuries including the patient's hemoglobin levels. There has often been a dilemma regarding levels of hemoglobin at which red cell blood transfusion (RCBT) should be performed. OBJECTIVE: To systematically review the literature to determine the usefulness of management protocols that have hemoglobin levels <10 g/dL vs <7 g/dL as an RCBT criterion. METHODS: Following the PRISMA statement, the search was constructed using terms and descriptors of the Medical Subject Heading (MeSH), combined with Boolean operators. Full text of these articles was studied, and outcome measures at 3-6 months were considered for patients who were given a RCBT at <10 g/dL or at 7 g/dL hemoglobin levels. RESULTS: A total of 4 articles were found suitable for inclusion in the meta-analysis. RCBT below 7 g/dL was not associated with an increased risk of mortality as compared to RCBT using the value of less than 10 g/dL. RCBT at lower levels of hemoglobin was also not associated with a poor neurological outcome (GOS 4-5) but rather RCBT at lower levels lead to better outcomes (GOS 1-3) and the association was significant. CONCLUSION: Allogenic RCBT was associated with poorer neurological outcomes, within a wide range of reported differences in the hemoglobin threshold to decide for RCBT in TBI patients. Restrictive RCBT strategy may be useful in moderate to severe TBI cases although the risk of anemia-induced cerebral injury needs further investigation regarding the risks and complications inherent to RCBT.

The effect of filum terminale sectioning for Chiari 1 malformation treatment: systematic review.

PURPOSE: Symptomatic Chiari type I malformation (CM) is treated with posterior fossa decompression with/ without duroplasty. Few authors suggested cerebellar tonsil caudal migration due to a supposed "caudal traction" of cranial nerve structures in a so-called occult tethered cord syndrome. For these authors, filum terminale (FT) sectioning may improve CM symptoms. The objective of this review is to evaluate the effect of FT sectioning on the treatment of CM. METHODS: Using the PRISMA guidelines for systematic reviews, we reviewed studies to evaluate patient's outcomes with CM who underwent FT sectioning. The MINORS instrument was used for methodological quality assessment. The included studies' levels of evidence (LOE) were classified according to the Oxford Centre of Evidence-Based Medicine. RESULTS: Two studies from the same group of authors were included. We cannot assure if the cited cases in the first study were also included in their latter published study. The described results suggest that outcomes were not collected in a standardized fashion. Outcomes are described vaguely as a percentage of improvement. Case series samples were small and included not only patients with CM but also patients with scoliosis and syringomyelia. The MINORS score reported that both studies had low methodological quality. Both included studies were classified as level 4 of evidence. CONCLUSION: There is no scientific support for filum terminale sectioning in patients with CM without evidence of tethered cord. This procedure may be considered experimental and should be validated in a strict criterion of inclusion clinical trial comparing outcomes in posterior fossa decompression.

Osteolysis after cervical disc arthroplasty.

PURPOSE: Cervical disc arthroplasty (CDA) has become an increasingly popular treatment for cervical degenerative disc disease. One potential complication is osteolysis. However, current literature on this topic appears limited. The purpose of this study is to elucidate the incidence, aetiology, consequence, and subsequent treatment of this complication. METHODS: A systematic literature review was performed according to the PRISMA guidelines. Studies discussing the causes, incidence and management of osteolysis after a CA were included. RESULTS: A total of nine studies were included. We divided these studies into two groups: (1) large case series in which an active radiological evaluation for osteolysis was performed (total = six studies), (2) case report studies, which discussed symptomatic cases of osteolysis (total = three). The incidence of asymptomatic osteolysis ranged from 8 to 64%; however, only one study reported an incidence of < 10% and when this case was excluded the incidence ranged from 44 to 64%. Severe asymptomatic bone loss (exposure of the implant) was found in less than 4% of patients. Bone loss from osteolysis appeared to occur early (< 1 year) after surgery and late (> 1 year) as well. Symptomatic patients with osteolysis often required revision surgery. These patients required removal of implant and conversion to fusion in the majority of the cases. CONCLUSIONS: Osteolysis after CDA is common; however, the majority of cases have only mild or asymptomatic presentations that do not require revision surgery. The timing of osteolysis varies significantly. This may be due to differences in the aetiology of osteolysis.

Temporal lobe structural evaluation after transsylvian selective amygdalohippocampectomy.

OBJECTIVE: Mesial temporal lobe epilepsy (MTLE) is the most common type of focal epilepsy in adolescents and adults, and in 65% of cases, it is related to hippocampal sclerosis (HS). Selective surgical approaches to the treatment of MTLE have as their main goal resection of the amygdala and hippocampus with minimal damage to the neocortex, temporal stem, and optic radiations (ORs). The object of this study was to evaluate late postoperative imaging findings on the temporal lobe from a structural point of view. METHODS: The authors conducted a retrospective evaluation of all patients with refractory MTLE who had undergone transsylvian selective amygdalohippocampectomy (SAH) in the period from 2002 to 2015. A surgical group was compared to a control group (i.e., adults with refractory MTLE with an indication for surgical treatment of epilepsy but who did not undergo the surgical procedure). The inferior frontooccipital fasciculus (IFOF), uncinate fasciculus (UF), and ORs were evaluated on diffusion tensor imaging analysis. The temporal pole neocortex was evaluated using T2 relaxometry. RESULTS: For the IFOF and UF, there was a decrease in anisotropy, voxels, and fibers in the surgical group compared with those in the control group (p < 0.001). An increase in relaxometry time in the surgical group compared to that in the control group (p < 0.001) was documented, suggesting gliosis and neuronal loss in the temporal pole. CONCLUSIONS: SAH techniques do not seem to totally preserve the temporal stem or even spare the neocortex of the temporal pole. Therefore, although the transsylvian approaches have been considered to be anatomically selective, there is evidence that the temporal pole neocortex suffers structural damage and potentially functional damage with these approaches.

Fractional anisotropy of the optic radiations correlates with the visual field after epilepsy surgery.

PURPOSE: This study assessed whether optic radiations (OR) microstructure after temporal lobe epilepsy (TLE) surgery correlated with visual field defects (VFD). METHODS: Patients were subjected to diffusion tensor imaging (DTI) tractography of the OR and Humphrey perimetry after TLE surgery. We used Spearman's test to verify correlations between tractographic parameters and perimetry mean deviation. Tractographic variables were compared between patients with VFD or intact perimetry. Multiple logistic regression was applied between DTI and perimetry values. DTI sensitivity and specificity were assessed with a receiver operating characteristic (ROC) curve to evaluate VFD. RESULTS: Thirty-nine patients had reliable perimetry and OR tractography. There was a significant correlation between (1) fractional anisotropy (FA) and both total (rho = 0.569, p = 0.0002) and quadrant (rho = 0.453, p = 0.0037) mean deviation and (2) radial diffusivity and total mean deviation (rho = - 0.350, p = 0.0286). There was no other significant correlation. Patients with VFD showed a significantly lower FA compared with patients with normal perimetry (p = 0.0055), and a 0.01 reduction in FA was associated with a 44% increase in presenting VFD after surgery (confidence interval, CI = 1.10-1.88; p = 0.0082). Using a FA of 0.457, DTI tractography showed a specificity of 95.2% and a sensitivity of 50% to detect VFD after surgery (area under the curve = 0.7619, CI = 0.6020-0.9218). CONCLUSION: The postoperative OR microstructure correlated with visual loss after epilepsy surgery. DTI postoperative OR tractography may be helpful in evaluating VFD.

Factors affecting diagnosis of primary pediatric central nervous system neoplasias in a developing country.

PURPOSE: Understand the variables that could interfere with diagnosis and prompt treatment in CNS childhood cancer in Brazil, a developing country with continental dimensions. METHODS: From 2005 to 2010, we retrospectively evaluated factors, which could represent a negative influence on the time period elapsing from the onset of symptoms until the diagnosis of the central nervous system (CNS) neoplasia in children and adolescents attended in our service. RESULTS: Two hundred seventeen records were analyzed retrospectively. Factors of the households were evaluated, and this data was related to the time period elapsing from presentation of the first symptoms until the diagnosis of CNS neoplasia. The average time elapsed from the onset of the symptoms until seeking medical assistance was 96 days, and from medical assistance to patient referral to a reference service was 33 days. The symptoms which most contributed to a shorter delay in diagnosis were changes in gait and paresis, mother's occupation, father's education level, patient gender, and living in the state of São Paulo. Besides that, variables such as male gender, mother's education level, and lower patient age were associated with an early diagnosis time. CONCLUSION: There is great difficulty in performing early diagnosis of CNS tumors, partly due to parent's inability to recognize signs and symptoms, and in part due to an educational deficit among healthcare professionals. Identification of measures that can minimize these causes of delay is fundamental to increasing the chance of cure and survival of these patients.

Using the keystone design perforator island flap in large myelomeningocele closure.

OBJECTIVE: Many repair techniques have been proposed to treat large myelomeningocele (MMC), and although effective in many cases, some of these techniques can be complex and time consuming, with complications such as cerebrospinal fluid (CSF) leakage, flap loss, tip necrosis, and wound dehiscence. The purpose of this study was to analyze cases of large skin defects and the methods applied and to report the outcomes of the keystone design perforator island flap (KDPIF) technique for large MMC closure. METHODS: The authors performed a retrospective review of all neonatal patients who had undergone KDPIF for MMC closure in the period from 2013 to 2018. All patients had a diagnosis of lumbosacral MMC based on obstetric ultrasound. The neurosurgeons and plastic surgeons had selected the cases after concluding that primary closure would be unlikely. The design of the flap is based on the randomly located vascular perforators, creating two identical opposing flaps to fashion a double keystone flap. During wound closure, V-Y advancement of each end of the double flap in the longitudinal axis creates redundancy in the central portion of the flap and reduces the horizontal tension. After discharge, both the neurosurgery and plastic surgery teams followed up all patients, tracking the results with photography. RESULTS: No skin flap dehiscence or necrosis, infection, or CSF leakage was detected, proving the reliability of the flap. One of the patients required further surgery for the large skin defects after insufficient intrauterine closure of the MMC and successfully underwent KDPIF treatment. Another patient (14.3%) had severe neonatal sepsis, which ultimately led to death. A ventriculoperitoneal shunt was required after the skin defect repair in 5 (83.3%) of the 6 surviving patients. Exceptional aesthetic results were achieved for all patients during the follow-up. CONCLUSIONS: The KDPIF technique is based on well-known vascular perforators of the intercostal, lumbar, and gluteal regions. Wound tension is widely distributed by the flap and, as a consequence, relevant tissue bulk, reliable vascularity, and important geometrical versatility are provided. In addition, most of the muscles and fascia are preserved, which is another advantage in terms of minimizing secondary morbidity to local tissue rearrangement. The use of KDPIF closure was successfully shown to be a viable alternative for more complex MMCs that present with large skin defects.

Post-operative nerve injuries after cervical spine surgery.

Although relatively rare, post-operative nerve injuries may occur after cervical spine procedures. The most common post-operative neural disorder is C5 nerve palsy. The risk factors for C5 nerve palsy are male gender, OPLL, and posterior cervical approaches. It generally presents with deltoid and/or biceps weakness, and may present immediately or several days after surgery. Treatment is generally conservative due to transient duration of symptoms, but evaluation of residual compression at C4-5 is essential. PTS (Parsonage-Turner syndrome) is an idiopathic plexopathy generally presenting with severe neuropathic pain in the shoulder, neck, and arms, followed by neurological deficits involving the upper brachial plexus. The deficits typically present in a delayed fashion after the onset of pain. Once residual nerve compression is ruled out, initial treatment is based on pain control and physical therapy. Post-operative C8-T1 nerve palsies occur with weakness of the five intrinsic muscles of the hand innervated by the medial nerve, with sensory symptoms in the territory innervated by the ulnar nerve (ulnar two digits of the hand), and also the medial forearm. The risk factors for C8-T1 nerve injuries after surgery are C7 pedicle subtraction osteotomies and posterior fixation of the cervico-thoracic junction, especially in patients with preoperative C7-T1 stenosis. A wide foraminal decompression at C7-T1 region is necessary to minimize risk of this complication. Finally, Horner's syndrome can occur post-operatively, especially after anterolateral approaches to the middle and lower levels of the cervical spine. It is characterized by ipsilateral papillary miosis, facial anhydrosis, and ptosis secondary to injury of the cervical sympathetic nerves. Avoid using the cautery on the lateral border of the longus colli muscle, where the sympathetic chain lies and place the retractors properly underneath the muscle to decrease the chance of sympathetic injuries. It can also occur from iatrogenic compression or injury to the T1 nerve root, as the sympathetic chain gets some of its fibers from that level. Understanding the most common potential nerve injuries after cervical spine procedures is helpful in prevention, early diagnosis, and appropriate management.