Supratentorial hemangioblastoma: correlation between phenotype, gender and vascular territory affected.

Supratentorial hemangioblastomas are rare, vascular lesions. The presence of peri-tumoral cysts and edema has meaningful clinical, diagnostic and therapeutic implications. Nevertheless, the pathogenesis of both cyst and edema formation is not fully understood. This study sought to determine if the radiologic phenotype of supratentorial hemangioblastoma is affected by the different cerebral arterial circulations. Review of the English-language literature from 1973 to 2023 yielded 53 cases of parenchymal supratentorial hemangioblastomas eligible for analysis. Patients were divided by the vascular territorial distribution of the lesions: anterior circulation (n = 36) or posterior circulation (n = 17), and the groups were compared for demographic, clinical, radiologic and molecular variables. Univariate analyses yielded a significant difference between the groups in five variables. Cystic changes and "classic" radiological phenotype were associated with hemangioblastomas of the posterior circulation (OR = 0.19, p = 0.045 and OR = 0.287, p = 0.048, respectively), while female gender, significant peritumoral edema and purely solid phenotype were associated with hemangioblastomas of the anterior circulation (OR = 3.384, p = 0.045 and OR = 5.25, p = 0.05 and OR = 14.0, p = 0.015; respectively). On multivariate analysis, solid phenotype and female gender remained significantly associated with the anterior circulation (OR = 36.04, p = 0.014 and OR = 4.45, p = 0.045). The incidence of von-Hippel Lindau disease was higher in the anterior-circulation group. Cystic tumors were present in all females in the posterior-circulation group compared to 43.4% in the anterior-circulation group (OR = 20.714, 95% CI 1.061 to 404.122; p = 0.045). Based on historical cases of supratentorial hemangioblastoma, this study shows that different tumor phenotypes are associated with the different cerebral circulations. Gender was also associated with differences in tumor distribution and radiologic phenotype. These novel data may improve our understanding of unique vascular diseases of the central nervous system.

[THERAPEUTIC OPTIONS FOR BRAIN OLIGOMETASTASES: COMPARISON BETWEEN SURGICAL RESECTION, STEREOTACTIC RADIOSURGERY, WHOLE BRAIN RADIATION THERAPY AND COMBINED MODULES IN RELATION TO SURVIVAL, FUNCTION AND OTHER CONSIDERATIONS].

INTRODUCTION: Brain metastases (BM) are a leading cause of morbidity and mortality in patients with systemic cancer. In the last two decades, an enormous improvement in controlling extra-cranial disease has been achieved, positively affecting the overall survival of patients. However, this has led to an increased number of patients who live long enough to develop BM. In addition, technological improvements in neurosurgery and radiotherapy caused both surgical resection and stereotactic radiosurgery (SRS) to become an integral part of the armamentarium when treating a patient with 1-4 BM. These increased therapeutic possibilities and combination of therapeutic options such as surgical resection, SRS, whole brain radiation therapy (WBRT) and lately targeted molecular therapy, have led to an enormous amount of, yet sometimes confusing, published data.

A Review of the Neurosurgical Management of Brain Metastases During Pregnancy.

OBJECTIVE: Patients with pregnancy-associated secondary brain tumors (PASBT) are challenging to manage. Because no guidelines for the management of such patients currently exist, we performed a systematic review of the literature using PRISMA guidelines with a discussion of management from a neurosurgeon's perspective. METHOD: Systematic review of the literature using PRISMA guidelines from 1999 to 2018. RESULTS: We identified 301 studies of which 16 publications (22 patients reporting 25 pregnancies, 20 deliveries, 5 early terminations) were suitable for final analysis. The most frequent primary cancers were breast (8/22, 36.36%), skin (6/22, 27.27%), and lung (5/22, 22.73%). Four patients (18.18%) had neurosurgical procedures during their pregnancies. Five patients (22.73%) received neurosurgical resection after their pregnancies. Nine patients (40.91%) received radiation therapy and seven patients (31.82%) received chemotherapy during pregnancy while seven patients (31.82%) received chemotherapy and radiation after pregnancy. There was 1 fetal death (5%) out of 20 healthy deliveries. Five pregnancies (20%) were terminated in the first trimester due to a need for urgent neurosurgical intervention. CONCLUSION: Management of PASBT remains a challenging issue. Maternal and fetal risks associated with surgical resection and teratogenicity due to adjuvant therapy should be discussed in the context of a multidisciplinary team. Timing of surgery and the use of systemic chemoradiation depends on the gestational age (GA) of the fetus, extent, and control of the mother's primary and metastatic disease. Guidelines need to be established to help neuro-oncology teams safely and effectively manage this group of patients.

Neuropsychological assessments and cognitive profile mostly associated with shunt surgery in idiopathic normal pressure hydrocephalus patients: diagnostic and predictive parameters and practical implications.

BACKGROUND: Cognitive decline is a well-documented feature of idiopathic normal pressure hydrocephalus (iNPH) that can be reversible following cerebrospinal fluid tap tests (CSF-TT). The current gold standard for selecting iNPH patients for shunt surgery is measurable improvement in gait tests following CSF-TT. However, the diagnostic significance and predictive role of pre-surgical cognitive evaluations in probable iNPH patients is still controversial. PURPOSE: To find the neuropsychological (NPSY) tests and cognitive aspects mostly associated with shunt surgery in iNPH. MATERIAL AND METHODS: A retrospective comparison between probable iNPH patients who, after undergoing CSF-TT with gait and cognitive evaluations, ended up receiving a shunt (group 1) and probable iNPH patients who ended up with no shunt surgery (group 2). Differences in the diagnostic and predictive results of variety of NPSY tests at baseline, pre-CSF-TT, and post-CSF-TT were used for thorough statistical calculations. RESULTS: A total of 147 patients with probable iNPH were included. Of those, 58 (39.45%, group 1) patients underwent shunt surgery, while 89 (60.55%, group 2) did not. For the vast majority of the cognitive tests used, no statistically significant differences were found between the groups at baseline (pre-CSF-TT). Following CSF-TT, the "naming" component of the Cognistat test was the only single test to show statically significant difference in improvement between the two groups. Combining at least two tests led to increased levels of accuracy and specificity; however, the sensitivity remained < 50. The only two combinations that were associated with sensitivity ≥ 70 were either any improvement in the Cognistat test (p = 0.627) or any improvement in either its naming, memory, or judgment components (p = 0.015). CONCLUSION: Cognitive tests, even when combined to cover several cognitive aspects, are not sensitive enough to act as an independent reliable diagnostic and predictive tool, especially when relying on their scores as baseline. In order to avoid cumbersome and unnecessary tests to our patients and to reduce the number of patients who are denied proper treatment due to misdiagnosis, we recommend to use NPSY tests that examine the cognitive aspects of naming and memory, in addition to 2-3 tests for executive functions.

Height as a risk factor in meningioma: a study of 2 million Israeli adolescents.

BACKGROUND: Meningiomas are the most common primary central nervous system tumors. Potential risk factors include obesity, height, history of allergy/atopy, and autoimmune diseases, but findings are conflicting. This study sought to assess the role of the different risk factors in the development of meningioma in adolescents/young adults. METHODS: The cohort included 2,035,915 Jewish men and women who had undergone compulsory physical examination between 1967 and 2011, at age 16 to 19 years, prior to and independent of actual military enlistment. To determine the incidence of meningioma, the military database was matched with the Israel National Cancer Registry. Cox proportional hazard models were used to estimate the hazard ratios for meningioma according to sex, body mass index (BMI), height, and history of allergic or autoimmune disease. RESULTS: A total of 480 subjects (328 females) were diagnosed with meningioma during a follow-up of 40,304,078 person-years. Median age at diagnosis was 42.1 ± 9.4 years (range 17.4-62.6). On univariate analysis, female sex (p < 0.01) and height (p < 0.01) were associated with risk of meningioma. When the data were stratified by sex, height remained a significant factor only in men. Spline analysis of the male subjects showed that a height of 1.62 m was associated with a minimum disease risk and a height of 1.85+ meters, with a significant risk. CONCLUSIONS: This large population study showed that sex and adolescent height in males (> 1.85 m) were associated with an increased risk of meningioma in adulthood.

Chiari I malformation and pregnancy: a comprehensive review of the literature to address common questions and to guide management.

BACKGROUND: The optimal management of Chiari I malformation during pregnancy remains uncertain. Labor contractions, which increase intracranial pressure, and neuraxial anesthesia both carry the theoretical risk of brainstem herniation given the altered CSF dynamics inherent to the condition. Mode of delivery and planned anesthesia, therefore, require forethought to avoid potentially life-threatening complications. Since the assumed potential risks are significant, we seek to systematically review published literature regarding Chiari I malformation in pregnancy and, therefore, to establish a best practice recommendation based on available evidence. METHODS: The English-language literature was systematically reviewed from 1991 to 2018 according to PRISMA guidelines to assess all pregnancies reported in patients with Chiari I malformation. After analysis, a total of 34 patients and 35 deliveries were included in this investigation. Additionally, a single case from our institutional experience is presented for illustrative purposes but not included in the statistical analysis. RESULTS: No instances of brain herniation during pregnancy in patients with Chiari I malformation were reported. Cesarean deliveries (51%) and vaginal deliveries (49%) under neuraxial blockade and general anesthesia were both reported as safe and suitable modes of delivery. Across all publications, only one patient experienced a worsening of neurologic symptoms, which was only later discovered to be the result of a previously undiagnosed Chiari I malformation. Several patients underwent decompressive suboccipital craniectomy to treat the Chiari I malformation during the preconception period (31%), during pregnancy (3%), and after birth (6%). Specific data regarding maternal management were not reported for a large number (21) of these patients (60%). Aside from one abortion in our own institutional experience, there was no report of any therapeutic abortion or of adverse fetal outcome. CONCLUSIONS: Although devastating maternal complications are frequently feared, very few adverse outcomes have ever been reported in pregnant patients with a Chiari I malformation. The available evidence is, however, rather limited. Based on our survey of available data, we recommend vaginal delivery under neuraxial blockade for truly asymptomatic patients. Furthermore, based on our own experience and physiological conceptual considerations, we recommend limiting maternal Valsalva efforts either via Cesarean delivery under regional or general anesthesia or by choosing assisted vaginal delivery under neuraxial blockade. There is no compelling reason to offer suboccipital decompression for Chiari I malformation during pregnancy. For patients with significant neurologic symptoms prior to conception, decompression prior to pregnancy should be considered.

[IS ROUTINE CT SCAN NECESSARY AFTER THE REMOVAL OF BENIGN BRAIN TUMORS?]

AIMS: Determine if early CT evaluation is justified in patients operated on for benign brain tumors. BACKGROUND: Researchers have recently questioned the common practice of referring all patients after cranial surgery for CT scans to rule out silent complications. METHODS: The cohort included 257 consecutive patients who underwent surgical removal of a benign brain tumor in the years 2011-2016. The neuroradiology scans performed before and after surgery were reviewed. The postoperative findings considered significant were hemorrhage in ≥50% of the tumor bed, ischemic changes, worsening brain edema, and mass effect. The relationship of the CT findings with the neurological outcome and their effect on the clinical management were evaluated. RESULTS: No significant complications were found by CT in 247 patients (96%). In the remaining 10 patients (4%), CT showed increased brain edema in 5 and hemorrhage in 5. The clinical management was influenced by the CT findings in 6/10 patients. One had a temporary neurological deficit. None died or required a second operation. CONCLUSIONS: Elective patients operated on uneventfully for benign brain tumors rarely benefit from routine CT after surgery. In most cases, CT follow-up can be replaced by careful neurological monitoring. Exceptions to this rule may be based on clinical judgment and local resources.

Accelerated growth of hemangioblastoma in pregnancy: the role of proangiogenic factors and upregulation of hypoxia-inducible factor (HIF) in a non-oxygen-dependent pathway.

Hemangioblastomas (HBs) are benign, highly vascular tumors, often characterized by loss of function of the von Hippel-Lindau (vHL) gene. They are the most common central nervous system tumor observed in vHL syndrome. Loss of function of the vHL gene creates a "pseudo-hypoxic" state, causing overactivation of hypoxia-inducible factor (HIF) and vascular endothelial growth factor (VEGF)-related pathways. In some cases, HBs can rapidly increase in size during pregnancy to then present acutely, which most frequently occurs after the 20th gestational week. These changes in size usually occur from enlargement of the cystic component of the HB. Due to their preferred location in the posterior fossa near critical structures as well as along the spinal cord, such cases can present with severe neurological deficits, requiring urgent surgical intervention in a multidisciplinary setting. However, the reasons for this acute flare-up during pregnancy remain poorly understood, as are the reasons why this occurs in only a subset of tumors. Unveiling the etiology for this clinical scenario can affect the treatment of HBs, as it will contribute to the understanding of the pathophysiology of such a transformation from a quiescent lesion to a symptomatic one, not only in the setting of pregnancy. Identifying the correct triggers and the conditions initiating and mediating this switch will enable us to develop preventive medications which should allow us to keep the tumor in its quiescent phase. In this pathophysiological review, we investigate the association between HB growth and pregnancy based on an analysis > 40 such published cases. We suggest that the proangiogenic state of pregnancy is the leading etiology for this striking association, and to support the argument, we discuss its potential impact on HIF overexpression in a non-hypoxic manner through activation of the PI3K/Akt/mTOR pathway by proangiogenic factors. Specifically, we discuss the involvement of placental growth factor (PlGF) and its receptor vascular endothelial growth factor receptor 1 (VEGFR-1) in various pathologic processes that can lead to the formation and growth of peritumoral edema and cysts, which are the primary causes for the development of any symptoms in HB. Both PlGF and VEGFR-1 are expressed at increased levels during pregnancy, and both have been reported as part of various pathological processes, including angiogenesis and tumorigenesis. The unique feature that both do essentially not show any significant negative impact on regular physiological processes makes them attractive therapeutic targets since very little side effects are expected. Further research into the effects of anti-PlGF or anti-VEGFR-1 therapy in HB is therefore recommended.

Management of quadrigeminal arachnoid cyst associated with obstructive hydrocephalus: report on stereotactic ventricular - cystic stenting.

Quadrigeminal arachnoid cysts (QAC) are usually accompanied by a symptomatic obstructive hydrocephalus. Several endoscopic and surgical treatments exist; however, the critical location of these cysts further complicates treatment and usually more than one procedure is required. In this report, a 31 year old female with QAC and associated obstructive hydrocephalus was successfully treated with stereotactic placement of a permanent ventricular - cystic stent (intraventricualr - cystic catheterization) in single - session. Intraventricular - cystic stenting provides a long lasting communication between these two compartments, allowing persistent "physiologic" solution to this challenging condition.

[DIFFUSE LOW GRADE GLIOMA: PERSONALIZED ADAPTATION OF SURGICAL RESECTION IN AN ERA OF TARGETED ONCOLOGICAL THERAPY].

INTRODUCTION: Diffuse low grade glioma (DLGG) is a primary, infiltrative brain tumor which grows slowly but steadily and eventually undergoes malignant transformation into a high grade glioma. Today, it is hard to generalize the treatment approaches for DLGG. Due to different genetic and clinical variables, there is a large gap in the treatment provided to different patients. This kind of gap requires personalized adaptation of the treatment for a long period. Although there has been significant progress in the molecular characterization of DLGG, we still lack an efficient oncological targeted therapy. On the other hand, during the past two decades, there has been a significant paradigm shift in the treatment of DLGG, with the current recommendation to perform a maximal safe resection as first line treatment. Our aspirations to preserve the high function abilities of these relatively young patients for a long period (median overall survival of 15 years), together with the intention to postpone the malignant transformation as late as possible, have led to increases in the prevalence of awake craniotomies for DLGG. In this surgical technique, the resection of the tumor is as wide as possible, according to its functional boundaries (and not its radiological - anatomical ones). This kind of resection allows us to preserve the functioning abilities of the patients while making a wide resection. This resection can be performed with full adaptation to the patient's will, as well as for the tumor's characteristics. The long-term treatment of patients with DLGG requires us to perform personalized adaptation in any therapeutic junction and in any case where the delicate balance between function of the patient and his oncological status needs to be preserved. This study reviews the different options for personalized treatment in DLGG and emphasize the importance of awake surgeries in these cases.

Granular cell tumor of the infundibulum: a systematic review of MR-radiography, pathology, and clinical findings.

INTRODUCTION: Granular cell tumors (GCTs) of the infundibulum are rare in practice and literature, resulting in a lack of evidence-based standard of care. We present two characteristic cases from our institution and perform a systematic review of the existing literature to further elucidate the presentation of this tumor and guide management. METHODS: A systematic literature search was conducted according to PRISMA guidelines, yielding 42 total individual reported GCTs suitable for evaluation. Available clinical presentation, magnetic resonance imaging (MRI) characteristics, pathology, surgical approaches, and outcomes were charted. We measured frequencies of clinical characteristics and performed an outcome comparison of open versus endoscopic surgical treatment. RESULTS: In this pooled dataset, GCT incidence was higher in females than males (3:1). Clinical presentation peaked in the fourth decade with tumor-related symptoms. MRI appearance was characterized by T1 isointensity (50%) and T2 hypointensity or isointensity (52%) with gadolinium contrast enhancement (74%). Histopathology demonstrated positive staining for PAS, PAS-D, S100, CD68, and TTF1. In a simple uncontrolled analysis, patients who underwent endoscopic surgery experienced more symptom improvement (p = 0.006) and lower incidence of new diabetes insipidus postoperatively (p = 0.047) versus patients who underwent open microsurgery. CONCLUSIONS: This first comprehensive review of GCTs of the infundibulum corroborates existing data and adds significant new MR-radiological information to the literature, notably a typical tumor appearance of T1 isointensity, T2 iso- to hypointensity, and gadolinium contrast enhancement. Future prospective studies should be conducted to validate our findings.

Vascular hyperpermeability as a hallmark of phacomatoses: is the etiology angiogenesis related to or comparable with mechanisms seen in inflammatory pathways? Part II: angiogenesis- and inflammation-related molecular pathways, tumor-associated macrophages, and possible therapeutic implications: a comprehensive review.

Phacomatoses are a special group of familial hamartomatous syndromes with unique neurocutaneous manifestations as well as characteristic tumors. Neurofibromatosis type 2 (NF2) and tuberous sclerosis complex (TSC) are representatives of this family. A vestibular schwannoma (VS) and subependymal giant cell tumor (SGCT) are two of the most common intracranial tumors associated with these syndromes, related to NF2 and TSC, respectively. These tumors can present with an obstructive hydrocephalus due to their location adjacent to or in the ventricles. Remarkably, both tumors are also known to have a unique association with elevated protein concentrations in the cerebrospinal fluid (CSF), sometimes in association with a non-obstructive (communicating) hydrocephalus. Of the two, SGCT has been shown to be associated with a predisposition to CSF clotting, causing a debilitating recurrent shunt obstruction. However, the exact relationship between high protein levels and clotting of CSF remains unclear, nor do we understand the precise mechanism of CSF clotting observed in SGCT. Elevated protein levels in the CSF are thought to be caused by increased vascular permeability and dysregulation of the blood-brain barrier. The two presumed underlying pathophysiological processes for that in the context of tumorigenesis are angiogenesis and inflammation. Both these processes are correlated to the phosphatidylinositol-3-kinase/Akt/mammalian target of rapamycin pathway which is tumorigenesis related in many neoplasms and nearly all phacomatoses. In this review, we discuss the influence of angiogenesis and inflammation pathways on vascular permeability in VSs and SGCTs at the phenotypic level as well as their possible genetic and molecular determinants. Part I described the historical perspectives and clinical aspects of the relationship between vascular permeability, abnormal CSF protein levels, clotting of the CSF, and communicating hydrocephalus. Part II hereafter describes the different cellular and molecular pathways involved in angiogenesis and inflammation observed in both tumors and explores the existing metabolic overlap between inflammation and coagulation. Interestingly, while increased angiogenesis can be observed in both tumors, inflammatory processes seem significantly more prominent in SGCT. Both SGCT and VS are characterized by different subgroups of tumor-associated macrophages (TAMs): the pro-inflammatory M1 type is predominating in SGCTs, while the pro-angiogenetic M2 type is predominating in VSs. We suggest that a lack of NF2 protein in VS and a lack of TSC1/TSC2 proteins in SGCT significantly influence this fundamental difference between the two tumor types by changing the dominant TAM type. Since inflammatory reactions and coagulation processes are tightly connected, the pro-inflammatory state of SGCT may also explain the associated tendency for CSF clotting. The underlying cellular and molecular differences observed can potentially serve as an access point for direct therapeutic interventions for tumors that are specific to certain phacomatoses or others that also carry such genetic changes.

Unique features of pregnancy-related meningiomas: lessons learned from 148 reported cases and theoretical implications of a prolactin modulated pathogenesis.

Meningiomas are some of the most frequently encountered adult intracranial tumors. Dramatic flare ups in size may occasionally be observed during pregnancy, leading to complicated clinical scenarios, with profound effects and substantial risks for both the mother's and the fetus's well-being. Despite the fact that such changes have largely been attributed to progesterone-based mechanisms, recent studies have put this theory into question or defied it. In order to assess these particular tumors carefully and to try and clarify the pathophysiology of such pregnancy-related meningioma growth, an in-depth review of the pertinent literature was undertaken. Based on clinical, radiographic, and pathological data gathered from 148 reported cases, we have found several unique features characterizing these pregnancy-related meningiomas. The presence of such observed features was found to be of high statistical significance when compared to their expected prevalence in the general population and included the following: (1) parasellar location, (2) anterior circulation blood supply, (3) visual symptoms at presentation, (4) high rate of clear-cell and chordoid morphology. A hypothesis is developed that these features are related to hormonal influences of the pituitary gland, and we discuss that this may be due to elevated prolactin levels. We encourage further research to test this exciting new theory.

Vascular hyperpermeability as a hallmark of phacomatoses: is the etiology angiogenesis comparable with mechanisms seen in inflammatory pathways? Part I: historical observations and clinical perspectives on the etiology of increased CSF protein levels, CSF clotting, and communicating hydrocephalus: a comprehensive review.

Phacomatoses are a special group of familial hamartomatous syndromes with unique neuro-cutaneous manifestations as well as disease characteristic tumors. Neurofibromatosis 2 (NF2) and tuberous sclerosis complex (TSC) are representatives of this family. Vestibular schwannoma (VS) and subependymal giant cell tumor (SGCT) are two of the most common intracranial tumors associated with NF2 and TSC, respectively. These tumors can present with obstructive hydrocephalus due to their location adjacent to or in the ventricles. However, both tumors are also known to have a unique association with an elevated protein concentration in the cerebrospinal fluid (CSF), sometimes in association with non-obstructive (communicating) hydrocephalus (HCP), the causality of which has been unclear. Furthermore, SGCTs have repeatedly been shown to have a predisposition for CSF clotting, causing debilitating obstructions and recurrent malfunctions in shunted patients. However, the exact relation between high protein levels and spontaneous clotting of the CSF is not clear, nor is the mechanism understood by which CSF may clot in SGCTs. Elevated protein levels in the CSF are thought to be caused by increased vascular permeability and dysregulation of the blood-brain barrier. The two presumed underlying pathophysiologic mechanisms for that, in the context of tumorigenesis, are angiogenesis and inflammation. Both mechanisms are correlated to the Pi3K/Akt/mTOR pathway which is a major tumorigenesis pathway in nearly all phacomatoses. In this review, we discuss the influence of angiogenesis and inflammation on vascular permeability in VSs and SGCTs at the phenotypic level as well as their possible genetic and molecular determinants. Part I describes the historical perspectives and clinical aspects of the relationship between vascular permeability, abnormal CSF protein levels, clotting of the CSF, and communicating HCP. Part II describes different cellular and molecular pathways involved in angiogenesis and inflammation in these two tumors and the correlation between inflammation and coagulation. Interestingly, while increased angiogenesis can be observed in both VS and SGCT, inflammatory processes seem more prominent in SGCT. Both pathologies are characterized by different subgroups of tumor-associated macrophages (TAM): the pro-inflammatory, M1 type is predominating in SGCTs while pro-angiogenetic, M2 type is predominating in VSs. We suggest that lack of NF2 protein in VS and lack of TSC1/2 proteins in SGCT determine this fundamental difference between the two tumor types, by defining the predominant TAM type. Since inflammatory reactions and coagulation processes are tightly connected, a "pro-inflammatory state" of SGCT can be used to explain the observed associated enhanced CSF clotting process. These distinct cellular and molecular differences may have direct therapeutic implications on tumors that are unique to certain phacomatoses or those with similar genetics.

Schwannoma of the trochlear nerve-an illustrated case series and a systematic review of management.

Schwannomas of cranial nerves in the absence of systemic neurofibromatosis are relatively rare. Among these, schwannomas of the trochlear nerve are even less common. They can be found incidentally or when they cause diplopia or other significant neurological deficits. Treatment options include observation only, neuro-ophthalmological intervention, and/or neurosurgical management via resection or sterotactic radiosurgery (SRS). In recent years, the latter has become an attractive therapeutic tool for a number of benign skull base neoplasm including a small number of reports on its successful use for trochlear Schwannomas. However, no treatment algorithm for the management of these tumors has been proposed so far. The goal of this manuscript is to illustrate a case series of this rare entity and to suggest a rational treatment algorithm for trochlear schwannomas, based on our institutional experience of recent cases, and a pertinent review of the literature. Including our series of 5 cases, a total of 85 cases reporting on the management of trochlear schwannomas have been published. Of those reported, less than half (40 %) of patients underwent surgical resection, whereas the remainder were managed conservatively or with SRS. Seventy-six percent (65/85) of the entire cohort presented with diplopia, which was the solitary symptom in over half of the cases (n = 39). All patients who presented with symptoms other than diplopia or headaches as solitary symptoms underwent surgical resection. Patients in the non-surgical group were mostly male (M/F = 3.5:1), presented at an older age and had shorter mean diameter (4.6 vs. 30.4 mm, p < 0.0001) when compared to the surgical group. Twelve patients in the entire cohort were treated with SRS, none of whom had undergone surgical resection before or after radiation treatment. Trochlear schwannoma patients without systemic neurofibromatosis are rare and infrequently reported in the literature. Of those, patients harboring symptomatic trochlear Schwannomas do not form a single homogenous group, but fall into two rather distinct subgroups regarding demographics and clinical characteristics. Among those patients in need of intervention, open microsurgical resection as well as less invasive treatment options exist, which all aim at safe relief of symptoms and prevention of progression. Both open microsurgical removal as well as SRS can achieve good long-term local control. Consequently, a tailored multidisciplinary treatment algorithm, based on the individual presentation and tumor configuration, is proposed.

Lumbar disk herniation during pregnancy: a review on general management and timing of surgery.

STUDY DESIGN: Narrative review with case illustration. OBJECTIVE: Provide an overview of existing management strategies to suggest a guideline for surgical management of lumbar disk herniation in pregnant women based on time of presentation. METHODS: We performed a narrative review on the topic using the PubMed database. A total of 63 relevant articles published after 1992 were identified, of which 17 fulfilled selection criteria. RESULTS: A total of 22 published cases of spine surgery for disk herniation during pregnancy were found in 17 studies on the topic. Prone positioning was reported in the majority of cases during the first and early second trimester. C-sections were performed prior to spine surgery in the prone position for the majority of patients operated during the third trimester. The left lateral position with continued pregnancy was preferred during the latter half of the second trimester when delivery of the fetus cannot yet be performed but surgery is indicated. CONCLUSION: Spine surgery during pregnancy is a rare scenario but can be performed safely when needed if providers adhere to general guidelines. Surgical approaches and overall management are influenced by the stage of pregnancy.

Meningiomas in pregnancy: timing of surgery and clinical outcomes as observed in 104 cases and establishment of a best management strategy.

BACKGROUND: There is a strong correlation between the level of circulating female sex hormones and the parturient growth of meningiomas. As a result, rapid changes in meningioma size occur during pregnancy, putting both the mother and fetus at risk. Large, symptomatic meningiomas require surgical resection, regardless of the status of pregnancy. However, the preferred timing of such complex intervention is a matter of debate. The rarity of this clinical scenario and the absence of prospective trials make it difficult to reach evidence-based conclusions. The aim of this study was to create evidence-based management guidelines for timing of surgery for pregnancy-related intracranial meningiomas. METHOD: The English literature from 1990 to 2016 was systematically reviewed according to PRISMA guidelines for all surgical cases of pregnancy-related intracranial meningiomas. Cases were divided into two groups: patients who have had surgery during pregnancy and delivered thereafter (group A) and patients who delivered first (group B). Groups were compared for demographic, clinical and radiological features, as well as for neurosurgical, obstetrical and neonatological outcomes. Statistical analysis was performed to assess differences. RESULTS: A total of 104 surgical cases were identified and reviewed, of which 86 were suitable for comparison and statistical analysis. Thirty-five patients (40%) underwent craniotomy for resection during pregnancy or at delivery (group A) and 51 patients (60%) underwent surgery after delivery (group B). Groups showed no significant differences in characteristics such as age at diagnosis, number of gestations, presenting symptoms, tumor site and tumor size. Despite a comparable distribution over the gestational trimesters, group A had significantly more patients diagnosed prior to the 27th gestational week (46 vs 17.5%, p = 0.0075). Group A was also associated with a significantly higher rate of both emergent craniotomies (40 vs 19.6%, p = 0.0048) and emergent Caesarian deliveries (47 vs 17.8%, p = 0.00481). The time from diagnosis to surgery was significantly longer in group B (11 weeks vs 1 week in group A, p = 0.0013). The rate of premature delivery was high but similar in both groups (∼70%). Risks of maternal mortality or fetal mortality were associated with group A (odds ratio = 14.7), but did not reach statistical significance. CONCLUSIONS: While surgical resection of meningioma during pregnancy may be associated with increased maternal and fetal mortalities, the overall neurosurgical, obstetrical and neonatological outcomes, as well as many clinical characteristics, are similar to patients undergoing resection postpartum. We believe that fetal survival chances have a significant impact on decision-making, as patients diagnosed at a later stage in pregnancy (≥27th week of gestation) were more likely to undergo delivery first. This complicated clinical scenario requires the close cooperation of multiple disciplines. While the mother's health and well-being should always be paramount in guiding management, we hope that the overall good outcomes observed by this systematic review will encourage colleagues to aim for term pregnancies whenever possible in order to reduce prematurity-related problems.

The Utility of Routine Intensive Care Admission for Patients Undergoing Intracranial Neurosurgical Procedures: A Systematic Review.

BACKGROUND: Patients who have undergone intracranial neurosurgical procedures have traditionally been admitted to an intensive care unit (ICU) for close postoperative neurological observation. The purpose of this study was to systematically review the evidence for routine ICU admission in patients undergoing intracranial neurosurgical procedures and to evaluate the safety of alternative postoperative pathways. METHODS: We were interested in identifying studies that examined selected patients who presented for elective, non-emergent intracranial surgery whose postoperative outcomes were compared as a function of ICU versus non-ICU admission. A systematic review was performed in July 2016 using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist of the Medline database. The search strategy was created based on the following key words: "craniotomy," "neurosurgical procedure," and "intensive care unit." RESULTS: The nine articles that satisfied the inclusion criteria yielded a total of 2227 patients. Of these patients, 879 were observed in a non-ICU setting. The most frequent diagnoses were supratentorial brain tumors, followed by patients with cerebrovascular diseases and infratentorial brain tumors. Three percent (30/879) of the patients originally assigned to floor or intermediate care status were transferred to the ICU. The most frequently observed neurological complications leading to ICU transfer were delayed postoperative neurological recovery, seizures, worsening of neurological deficits, hemiparesis, and cranial nerves deficits. CONCLUSION: Our systematic review demonstrates that routine postoperative ICU admission may not benefit carefully selected patients who have undergone elective intracranial neurosurgical procedures. In addition, limiting routine ICU admission may result in significant cost savings.

Single-session, transarterial complete embolization of Galenic dural AV fistula.

Galenic dural arteriovenous fistula (DAVF) represents a unique, hard to treat subgroup of tentorial DAVFs. We present an unusual case of hemorrhagic Galenic DAVF in a 54-year-old woman. The fistula drained directly to the vein of Galen through multiple feeders. Complete occlusion of the fistula was achieved through transarterial embolization. Deep venous drainage remained intact and the patient recovered well. To our knowledge, this is the first report on complete closure of hemorrhagic Galenic DAVF using transarterial embolization with complete obliteration of vein of Galen. The presence of nonfunctioning straight sinus may have contributed to the success of treatment and it may be considered as a predictive marker for endovascular embolization.

Persistent communicating hydrocephalus in adult tuberous sclerosis patients: a possible therapeutic role for everolimus.

Subependymal giant cell tumor (SGCT) is a benign intraventricular tumor, usually located near the foramen of Monro. It is almost always associated with tuberous sclerosis complex (TSC). SGCTs may obstruct cerebrospinal fluid (CSF) pathways. Rarely, they may secrete a protein-rich exudate, causing communicating hydrocephalus. Surgery is indicated for symptomatic lesions or growing asymptomatic lesions. The operative approach to SGCT has shifted from simple shunt placement to a more aggressive approach, leading to early attempts at gross total resection. Recently, the mTOR inhibitor everolimus has been approved for treating SGCT. In this article, we present two cases of recurrent shunt malfunctions in adult TSC patients with protein-secreting SGCTs. We describe the complexity of treating such patients with an emphasis on the role mTOR inhibitors may have in their management. We also review the literature on surgical management of SGCT-related hydrocephalus.