Posterior Fossa Tumor Surgery Research Articles

Prevalence of dysphagia following posterior fossa tumor resection: a systematic review and meta‑analysis

ObjectiveDysphagia is common in individuals who have undergone posterior fossa tumor (PFT) resection and negatively impacts on the individual’s quality of life, nutritional status, and overall health. We aimed to quantitatively synthesize data from studies of the prevalence of dysphagia following PFT resection.MethodsPubMed, Web of Science, the Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), Wanfang database, and VIP database were searched for case-control and cross-sectional studies that evaluated the prevalence of dysphagia after PFT surgery. Meta-analyses were performed to determine the prevalence of dysphagia. Subgroup and meta-regression analyses were performed to determine the sources of heterogeneity among the studies.ResultsA total of 22 studies were included, involving 20,921 cases. A meta-analysis of the random-effects model showed that the pooled global prevalence of dysphagia following PFT resection was 21.7% (95% confidence interval: 16.9–26.6). The subgroup and meta-regression analyses demonstrated that participant age (P < 0.001), assessment methods (P = 0.004), and geographical region of the study participants (P = 0.001) were sources of heterogeneity among the studies.ConclusionsDysphagia has a high prevalence following PFT resection. Individuals with PFTs who are at a high risk for dysphagia should be identified early through screening. Multidisciplinary diagnosis and treatment of dysphagia are required to improve the outcomes in the early stages after PFT resection.

MDB-30. ZOLPIDEM, A PROMISING DRUG TO IMPROVE POSTOPERATIVE CEREBELLAR MUTISM SYNDROME (CMS): RETROSPECTIVE STUDY OF 19 PEDIATRIC PATIENTS WITH POSTERIOR FOSSA TUMORS

Abstract INTRODUCTION Postoperative Cerebellar Mutism Syndrome (CMS) affects up to 25% of patients undergoing surgeries for posterior fossa (PF) tumors. There is no established treatment for CMS, although zolpidem has become widespread after reporting remarkable responses in some cases. However, there is very limited scientific evidence, prompting us to document our experience with zolpidem. OBJECTIVES To evaluate the efficacy and safety of zolpidem in patients with postoperative CMS in PF tumors. METHODS Observational, descriptive, retrospective study conducted at our institution. Patients &amp;lt;21 years diagnosed with CMS following PF tumor surgery between 2011-2023 and treated with zolpidem were included. Demographic and clinical data, therapies, CMS scales, and outcomes were collected. RESULTS Nineteen patients met the criteria, 84% males, median age 8 years (range, 9 months-19 years), and median follow-up time 30 months (range, 2-126). Diagnoses included 58% medulloblastoma, 21% pilocytic astrocytoma, 10.5% ependymoma, 10.5% others. CMS mutism scale was rated mild, moderate and severe in 5%, 21% and 74%, respectively. Median zolpidem administration was 31 days (range, 2-241) and median maximum dose was 0.25 mg/kg/day (range, 0.10-0.90). Mutism scores improved in 37% (7/19), 53% (8/15) and 64% (9/14) of patients that received zolpidem for at least 48h, 7 and 14 days, respectively. Subjective improvement in communication and interaction was observed in 74% (14/19). Only three patients with mild somnolence and one with initial irritability and insomnia were reported. CONCLUSIONS To our knowledge, this is the largest study of patients treated with zolpidem for CMS. A considerable proportion of children improved their language abilities within the first 24-48h, but some patients may even benefit from more prolonged treatment. Most children showed an adequate tolerance with very few side effects. Further studies are urgently needed, preferably within a randomized clinical trial, to find the real efficacy, appropriate dosage, and duration of zolpidem.

Outcome of Midline Posterior Cranial Fossa Tumor Surgery with Preoperative Ventriculo - Peritoneal (V-P) Shunt in Children

Introduction: Pediatric patients with midline posterior cranial fossa tumors present with features of raised intracranial pressure due to development of hydrocephalus. Due to the big size tumour and lack of facility we did Ventriculoperitoneal shunt before definitive surgery for all patients. Material and Methods: This cross-sectional experimental study was carried out on 55 consecutive patients with midline posterior cranial fossa brain tumors with obstructive hydrocephalus with age ranged from 3 to 15 years got admitted in the Department of Neurosurgery, Bangabandhu Sheikh Mujib Medical University from March 2021 to April 2023. We did preoperative ventriculoperitoneal shunt before definitive surgery but didn’t do the Endoscopic third ventriculostomy. Results: In this study, the age of the patients was 3-15 years, the mean age was 9.47+_3.18 and the peak incidence was 11-15 years which was 20(36.36%). Majority of the patients was male (56%), male female ratio was 1.27:1. Most of the children were presented with headache 51(92.73%) followed by papilloedema 47(85.45%), vomiting 46(83.64%), gait disturbance 37(67.27%), diminution of vision 31(56.36%), swallowing difficulty 12(21.82%), cranial nerve palsy 12(21.82%). 19 patients developed postoperative complications among them 15(27.27%) was meningitis followed by wound infection 7(12.73%), pseudomeningocele 8(14.55%), csf leakage 4(7.27%), hydrocephalous 3(5.45%). Logistic regression analysis was non-significant statistically in my study. Discussion and Conclusion: In conclusion we found satisfactory outcome of doing pr-operative VP Shunt in posterior fossa midline tumor causing obstructive Hydrocephalus in children, however major postoperative complications were development of hydrocephalus, CSF leak, pseudo meningocele, wound infection and meningitis. Future prospective studies with sufficient sample size are warranted to reach a definitive conclusion.

Duraplasty with autologous cervical fascia in pediatric posterior fossa tumor surgery: a single-center experience with 214 cases.

Posterior fossa surgeries for pediatric tumors pose challenges in achieving optimal dural repair and duraplasty is usually required. Autografts, allografts, xenografts, and synthetic substitutes can be used for duraplasty. Autologous cervical fascia can be a safe and reliable graft option for duraplasty after posterior fossa surgeries. This study aims to investigate the outcomes of duraplasty with autologous cervical fascial graft in children after posterior fossa surgery for pediatric brain tumors. Pediatric patients with posterior fossa tumor who underwent surgery between March 2001 and August 2022 were retrospectively reviewed. Data on demographics, preoperative symptoms, diagnosis, tumor characteristics, hydrocephalus history, and postoperative complications, including cerebrospinal fluid (CSF) leakage, pseudomeningocele, and meningitis were collected. Logistic regression analysis was performed to explore risk factors for postoperative complications. Patient cohort included 214 patients. Autologous cervical fascia was used in all patients for duraplasty. Mean age was 7.9 ± 5.3years. Fifty-seven patients (26.6%) had preoperative hydrocephalus and 14 patients (6.5%) received VPS or EVD perioperatively. Postoperative hydrocephalus was present in 31 patients (14.5%). Rates of CSF leak, pseudomeningocele, and meningitis were 4.2%, 2.8%, and 4.2% respectively. Logistic regression analysis revealed that postoperative EVD and VPS placement were the factors associated with postoperative complications. Autologous cervical fascia is a safe and reliable option for duraplasty with minimal risk of postoperative complications. The straightforward surgical technique and with no additional cost for harvesting the graft renders autologous cervical fascia a favorable alternative for resource-limited countries or surgical settings.

Evaluation of safety of fluoxetine for cerebellar mutism syndrome in children after posterior fossa surgery

BackgroundCerebellar mutism syndrome (CMS) occurs in 8–29 % of children undergoing posterior fossa tumor surgery. Its main symptoms are mutism and emotional lability. Although it is always transient, recovery time can be lengthy with long-term cognitive sequelae. There is no approved drug treatment for CMS, but some drugs are used in everyday medical practice. One of these is fluoxetine, which has been used for many years in our institution. The main objective of this study was to establish the safety profile of fluoxetine in this condition. Materials and methodsThe records of patients admitted to the pediatric intensive care unit after brain surgery at Angers University Hospital from 2010 to 2020 were reviewed. Children aged 2 years and older who underwent a posterior fossa tumor surgery and were diagnosed with CMS were included. Data on patient characteristics, prescription of fluoxetine treatment, side effects if any, and complete mutism duration were collected. ResultsAmong 246 patients admitted to the pediatric intensive care unit for brain surgery during the study period, 23 had CMS and eight were prescribed fluoxetine. No serious adverse event related to fluoxetine was reported. Complete mutism duration did not differ significantly between the fluoxetine group and the non-fluoxetine group(p = 0.22). However, the treatment was initiated after recovery from complete mutism in half of the treated patients. ConclusionThis study suggests a positive safety profile of fluoxetine used in postoperative CMS. It does not answer the question of whether the treatment is effective for this indication. A randomized controlled trial based on a syndrome severity scale should be conducted to provide a more reliable assessment of the efficacy and safety of fluoxetine.

Incidence and Risk Factors of Surgical Site Infection After Cranial Surgery for Patients with Brain Tumors: A Systematic Review and Meta-analysis

Surgical site infections after craniotomy (SSI-CRANs) are a serious adverse event given the proximity of the wound to the central nervous system. SSI-CRANs are associated with substantial patient morbidity and mortality. Despite the importance and recognition of this event in other surgical fields, there is a paucity of evidence in the neurosurgical literature devoted to SSI-CRAN specifically in patients after brain tumor surgery. Systematic searches of Medline, Embase, and Cochrane Central were undertaken. The primary outcome was the incidence of SSI-CRAN at 30 and 90 days. Secondary outcomes were risk factors for SSI-CRAN. Thirty-seven studies reporting 91,907 patients with brain tumors who underwent cranial surgery were included in the meta-analysis. Pooled incidence of SSI-CRAN at 30 and 90 days was 4.03% (95% CI: 2.94%-5.28%, I2= 97.3) and 6.17% (95% CI: 3.16%-10.07%, I2= 97.3), respectively. Specifically, incidence of SSI-CRAN following surgery for posterior fossa tumors was the highest at 9.67% (95% CI: 5.98%-14.09%, I2= 75.5). Overall pooled incidence of readmission within 30 days and reoperation due to SSI-CRAN were 13.9% (95% CI: 12.5%-15.5%, I2= 0.0) and 16.3% (95% CI: 5.4%-31.3%, I2= 72.9), respectively. Risk factors for SSI-CRAN included reintervention (risk ratio [RR] 1.58, 95% CI: 1.22-2.04, I2= 0.0), previous radiotherapy (RR 1.69, 95% CI: 1.20-2.38, I2= 0.0), longer duration of operation (mean difference 64.18, 95% CI: 3.96-124.40 minutes, I2= 90.3) and cerebrospinal fluid (CSF) leaks (RR 14.26, 95% CI: 2.14-94.90, I2= 73.2). SSI-CRAN affects up to 1 in 14 patients with brain tumors. High-risk groups include those with reintervention, previous radiotherapy, longer duration of operation, and CSF leaks. Further prospective studies should focus on bundles of care that will reduce SSI-CRAN.

The risk factors for silent aspiration: A retrospective case series and literature review.

Evidence shows that 20%-30% of patients who aspirate do so silently. Research to date has not demonstrated clear evidence to indicate which patients are at higher risk of silent aspiration. Our aim was to use univariate logistic regression analysis of retrospective case review to determine potential patterns of silent aspiration. We conducted a retrospective analysis of 455 fiberoptic endoscopic evaluation of swallowing (FEES) reports. The patients were divided into four groups: G1 - neurological diseases (n = 93), G2 - head and neck surgery (n = 200), G3 - gastroenterological diseases (n = 94) and G4 - other patients (n = 68). Data included the occurrence or absence of saliva penetration or aspiration, of silent fluid/solid food penetration or aspiration, type of penetration or aspiration, occurrence of cranial nerve paresis, radiotherapy and tracheostomy. Univariate logistic regression was used to evaluate independent risk factors of silent aspiration in the study population. Three models with different independent variables were considered. There is a statistically significant difference in the frequency of occurrence of silent penetration and aspiration within the groups (p < 0.001), with intraglutative being most frequent. Fluid and food penetration and aspiration correlated with saliva penetration and aspiration in all groups (p < 0.001). Cranial nerve paresis (IX and X), radiotherapy and tracheostomy correlate with saliva penetration and aspiration (p = 0.020 for cranial nerve paresis; p = 0.004 for radiotherapy; p < 0.001 for tracheostomy). One hundred and fifteen patients (45.81%) in the subgroup of patients with intraglutative aspiration had cranial nerve paresis (IX, X or IX-X). Patients who should be prioritised or considered to be at a higher need of instrumental swallowing evaluation are those with IX and X cranial nerve paresis, tracheostomy and those who have had radiotherapy, with saliva swallowing problems, especially after paraganglioma, thyroid and parathyroid glands and middle and posterior fossa tumour surgery. What is already known on the subject Clinical signs of penetration or aspiration include coughing, throat clearing and voice changes, while silent penetration or aspiration patients aspirate without demonstrating any clinical symptoms. The most common consequences of silent aspiration include aspiration pneumonia, recurrent lower respiratory tract infections and respiratory failure. Additionally, malnutrition and dehydration can be indicators of silent aspiration. Patients may unknowingly reduce their oral intake and lose weight. Retrospective studies have shown that 20%-30% of patients aspirate silently (e.g. patients after stroke, acquired brain injury, head and neck cancer treatment, prolonged intubation). Clinical examination of swallowing can miss up to 50% of cases of silent aspiration. What this paper adds to existing knowledge Currently, silent aspiration is often discussed in neurological literature, but its applications to head and neck surgery are limited. In this study, we identify head and neck surgery patients who should be prioritised or considered to be in higher need of instrumental swallowing evaluation due to a higher risk of silent aspiration. What are the potential or actual clinical implications of this work? Post-treatment structural changes can result in lower cranial nerve paresis (IX, X, XII) and face injury, in which vagus and glossopharyngeal nerves are injured. After tracheostomy and radiotherapy, patients with problems swallowing saliva need careful clinical examination, particularly cranial nerve examination.

National multicentered retrospective review of clinical and intraoperative factors associated with the development of cerebellar mutism after pediatric posterior fossa tumor resection.

Cerebellar mutism (CM) is characterized by a significant loss of speech in children following posterior fossa (PF) surgery. The biological origin of CM remains unclear and is the subject of ongoing debate. Significant recovery from CM is less likely than previously described despite rigorous multidisciplinary neuro-rehabilitational efforts. A national multi-centered retrospective review of all children undergoing PF resection in four midsized Canadian academic pediatric institutions was undertaken. Patient, tumor and surgical factors associated with the post-operative development of CM were reviewed. Retrospective identification of PF surgery patients including those developing and those that did not (internal control). The study identified 258 patients across the 4 centers between 2010 and 2020 (mean age 6.73years; 42.2% female). Overall, CM was experienced in 19.5% of patients (N = 50). Amongst children who developed CM histopathology included medulloblastoma (35.7%), pilocytic astrocytoma (32.6%) and ependymoma (17.1%). Intraoperative impression of adherence to the floor of the 4th ventricle was positive in 36.8%. Intraoperative abrupt changes in blood pressure and/or heart rate were identified in 19.4% and 17.8% of cases. The clinical resolution of CM was rated to be complete, significant resolution, slight improvement, no improvement and deterioration in 56.0%, 8.0%, 20.0%, 14.0% and 2.0%, respectively. In the cohort of children who experienced post-operative CM as compared to their no-CM counterpart, proportionally more tumors were felt to be adherent to the floor of the 4th ventricle (56.0% vs 49.5%), intraoperative extent of resection was a GTR (74% vs 68.8%) and changes in heart rate were noted (≥ 20% from baseline) (26.0% vs 15.9%). However, a multiple regression analysis identified only abrupt changes in HR (OR 5.97, CI (1.53, 23.1), p = 0.01) to be significantly associated with the development of post-operative CM. As a devastating surgical complication after posterior fossa tumor surgery with variable clinical course, identifying and understanding the operative cues and revising intraoperative plans that optimizes the child's neurooncological and clinical outcome are essential.

Morphological and ultrastructural investigation of the posterior atlanto-occipital membrane: Comparing children with Chiari malformation type I and controls.

The fibrous posterior atlanto-occipital membrane (PAOM) at the craniocervical junction is typically removed during decompression surgery for Chiari malformation type I (CM-I); however, its importance and ultrastructural architecture have not been investigated in children. We hypothesized that there are structural differences in the PAOM of patients with CM-I and those without. In this prospective study, blinded pathological analysis was performed on PAOM specimens from children who had surgery for CM-I and children who had surgery for posterior fossa tumors (controls). Clinical and radiographic data were collected. Statistical analysis included comparisons between the CM-I and control cohorts and correlations with imaging measures. A total of 35 children (mean age at surgery 10.7 years; 94.3% white) with viable specimens for evaluation were enrolled: 24 with CM-I and 11 controls. There were no statistical demographic differences between the two cohorts. Four children had a family history of CM-I and five had a syndromic condition. The cohorts had similar measurements of tonsillar descent, syringomyelia, basion to C2, and condylar-to-C2 vertical axis (all p>0.05). The clival-axial angle was lower in patients with CM-I (138.1 vs. 149.3 degrees, p = 0.016). Morphologically, the PAOM demonstrated statistically higher proportions of disorganized architecture in patients with CM-I (75.0% vs. 36.4%, p = 0.012). There were no differences in PAOM fat, elastin, or collagen percentages overall and no differences in imaging or ultrastructural findings between male and female patients. Posterior fossa volume was lower in children with CM-I (163,234 mm3 vs. 218,305 mm3, p<0.001), a difference that persisted after normalizing for patient height (129.9 vs. 160.9, p = 0.028). In patients with CM-I, the PAOM demonstrates disorganized architecture compared with that of control patients. This likely represents an anatomic adaptation in the presence of CM-I rather than a pathologic contribution.

Postoperative cerebellar mutism syndrome is an acquired autism-like network disturbance.

Cerebellar mutism syndrome (CMS) is a common and debilitating complication of posterior fossa tumor surgery in children. Affected children exhibit communication and social impairments that overlap phenomenologically with subsets of deficits exhibited by children with Autism spectrum disorder (ASD). Although both CMS and ASD are thought to involve disrupted cerebro-cerebellar circuitry, they are considered independent conditions due to an incomplete understanding of their shared neural substrates. In this study, we analyzed postoperative cerebellar lesions from 90 children undergoing posterior fossa resection of medulloblastoma, 30 of whom developed CMS. Lesion locations were mapped to a standard atlas, and the networks functionally connected to each lesion were computed in normative adult and pediatric datasets. Generalizability to ASD was assessed using an independent cohort of children with ASD and matched controls (n = 427). Lesions in children who developed CMS involved the vermis and inferomedial cerebellar lobules. They engaged large-scale cerebellothalamocortical circuits with a preponderance for the prefrontal and parietal cortices in the pediatric and adult connectomes, respectively. Moreover, with increasing connectomic age, CMS-associated lesions demonstrated stronger connectivity to the midbrain/red nuclei, thalami and inferior parietal lobules and weaker connectivity to the prefrontal cortex. Importantly, the CMS-associated lesion network was independently reproduced in ASD and correlated with communication and social deficits, but not repetitive behaviors. Our findings indicate that CMS-associated lesions may result in an ASD-like network disturbance that occurs during sensitive windows of brain development. A common network disturbance between CMS and ASD may inform improved treatment strategies for affected children.

Role of Neuron-Specific Enolase, D-Dimer and C-Reactive Protein in the Cranial Nerve Injury After Surgery of Posterior Fossa Tumor

Cranial nerve injury after posterior cranial fossa tumor surgery (PCFTS) is a common symptom in clinic. Intracranial pressure (ICP) monitoring has been widely used in patients with severe posterior cranial fossa injuries. By establishing a rat model of PCFT, we explore the correlation between neuron-specific enolase (NSE), D-Dimer (D-D) and C-reactive protein (CRP) and provide the better clinical reference to cranial fossa injury treatment. 30 SD female rats aged 20–22 months; randomly divided them into control groups and experimental groups and experimental rats were further divided into 12 for moderately increased group (21–40 mmHg) and 8 for severely increased group (&gt;40 mmHg) to measure NSE, D-D, and CRP and analyze their relationship. NSE, DD, and CRP in severely increased group and moderately increased group were significantly higher than those in control group. NSE (103.69±7.84) μg/L, DD (1.52±0.25) mg/L, CRP (47.63)±8.59) mg/L in severely increased group was significantly higher than moderately increased group (NSE (61.77±30.11) μg/L, DD (0.97± 0.37) mg/L, CRP (30.65± 9.56) mg/L) (P &lt; 0.05). ICP is positively correlated with NSE, DD and CRP (r = 0.775, P = 0.000, intracranial pressure=18.589+0.254NSE; r =0.872, P =0.000, IC=10.564+0.254 DD; r =0.825, P =0.000, ICP = 9.73+0.774CRP). There is a positive correlation between cranial nerve injury and NSE, D-dimer and CRP after PCFTS. It can be evaluated by detecting the above values to assess the degree of cranial nerve injury so as to predict the patient’s condition.

Effect of endoscopic third ventriculostomy on the prevention of hydrocephalus and the need for shunting in patients undergoing surgery for posterior fossa masses, a comparative study

BackgroundDue to the compressive effect of the brain masses, hydrocephalus treatment is mainly achieved by shunting and discharge of fluid. However, some reports have shown the potential adverse effects of this method and its potential contraindications that result in focusing on preventive approaches like endoscopic third ventriculostomy (ETV). Hence, in the present study, the authors undertook a study to examine the hypothesis that preoperative ETV could reduce the likelihood of hydrocephalus and the need for shunting in patients undergoing surgery for posterior fossa tumors. MethodsIn the current cross-sectional study, 40 consecutive patients were scheduled for surgery to remove posterior fossa masses using ETV preoperatively (n = 23) or were considered as the controls with no preoperative ETV (n = 17). Afterward, these patients were followed up for 2 months after surgery regarding hydrocephalus and the need for shunt insertion. The postoperative change in the ventricular-cranial ratio (VCR) was also compared in 2 groups. ResultsOf 23 patients in the ETV group, none required postoperative shunting due to the lack of evidence supporting hydrocephalus; however, 7 patients were found to require shunting in the non-ETV group. Notably, the value of VCR significantly reduced in both groups with no significant difference. ConclusionETV protocol before the surgical removal of posterior fossa tumors can effectively reduce the rate of postoperative hydrocephalus, decreasing the need for postoperative shunting.

Cerebellar Mutism after posterior fossa tumor surgery: is it predictable, preventable, treatable?

Introduction: Posterior fossa tumors pose challenges in pediatric neurosurgery and can lead to complications such as cerebellar mutism, affecting speech and motor abilities. This study aims to describe the evolution of cerebellar mutism and identify relevant factors in its pathophysiology and prognosis. Methods: A review was conducted on three cases of children who underwent surgery for posterior fossa tumors by the same surgical team and developed postoperative cerebellar mutism. The study analyzed preoperative clinical presentation, mutism manifestation, and recovery. Additionally, a literature review was performed on the emergence, evolution, and prognosis. Results: Case 1 involved a 3-year-old girl with medulloblastoma who experienced mutism, behavioral changes, and self-mutilation after surgery. Symptoms resolved after one month but recurred with a subsequent operation, resolving again after a month. Case 2 featured a 15-year-old girl who developed severe posterior fossa syndrome, including mutism, dysarthria, aphasia, and motor impairments. With support care, she gradually improved over a year. Case 3 involved a 4-year-old boy with cerebral palsy and a posterior fossa tumor. He experienced akinetic mutism, resolved over time with rehabilitation therapies. Discussion: Cerebellar mutism following posterior fossa surgery has implications for patient recovery. It primarily involves impairment of cerebellar outflow pathways rather than direct brainstem or cortical lesions. Identifying at-risk patients remains challenging, though younger age and specific tumor characteristics may increase the likelihood of mutism. Rehabilitation, including physical and speech therapies, plays a crucial role in promoting recovery. Effective communication and support for patients and their families are essential during the recovery process.

Preoperative word-finding difficulties in children with posterior fossa tumours: a European cross-sectional study.

Posterior fossa tumour surgery in children entails a high risk for severe speech and language impairments, but few studies have investigated the effect of the tumour on language prior to surgery. The current crosslinguistic study addresses this gap. We investigated the prevalence of preoperative word-finding difficulties, examined associations with medical and demographic characteristics, and analysed lexical errors. We included 148 children aged 5-17years with a posterior fossa tumour. Word-finding ability was assessed by means of a picture-naming test, Wordrace, and difficulties in accuracy and speed were identified by cut-off values. A norm-based subanalysis evaluated performance in a Swedish subsample. We compared the demographic and medical characteristics of children with slow, inaccurate, or combined slow and inaccurate word finding to the characteristics of children without word-finding difficulties and conducted a lexical error analysis. Thirty-seven percent (n = 55) presented with slow word finding, 24% (n = 35) with inaccurate word finding, and 16% (n = 23) with both slow and inaccurate word finding. Children with posterior fossa tumours were twice as slow as children in the norming sample. Right-hemisphere and brainstem location posed a higher risk for preoperative word-finding difficulties, relative to left-hemisphere location, and difficulties were more prevalent in boys than in girls. The most frequent errors were lack of response and semantically related sideordinated words. Word-finding difficulties are frequent in children with posterior fossa tumours, especially in boys and in children with right-hemisphere and brainstem tumours. Errors resemble those observed in typical development and children with word-finding difficulties.

Cerebellar Mutism Syndrome After Posterior Fossa Tumor Surgery in Children—A Retrospective Single-Center Study

Cerebellar mutism syndrome (CMS) is a well-known complication following posterior fossa tumor surgery in pediatric patients. We evaluated the incidence of CMS in our institute and analyzed association with multiple risk factors, such as tumor entity, surgical approach, and hydrocephalus. All pediatric patients who received an intra-axial tumor resection in the posterior fossa between January 2010 and March 2021 were included for retrospective analysis. Various data points, including demographic, tumor-associated, clinical, radiological, surgery associated, complications and follow-up data were collected and statistically evaluated for association with CMS. 63 surgeries in 60 patients were included with a median age of 8 years. Pilocytic astrocytoma was mostly represented by 50%, followed by medulloblastoma in 28%, and ependymomas in 10%. Complete resection was achieved in 67% versus subtotal in 23%, and partial resection in 10%. Telovelar approach was the most used in 43 % compared to transvermian in 8%. 10 children (17%) developed CMS and showed marked improvement but with residual deficits. Significant risk factors were transvermian approach (p=0.03), vermian splitting whenever added to other approach (p=0.002), initial presentation with acute hydrocephalus (p=0.02), and remaining hydrocephalus after tumor surgery (p=0.004). Our CMS rate compares to those described in literature. Despite the limitations of our study as a retrospective one, we found CMS was not only associated with a transvermian approach, but also occurs after using a telovelar approach, however to a lesser extent. Acute hydrocephalus at initial presentation necessitating urgent management was significantly associated with higher incidence of CMS.

Asymptomatic Postoperative Cerebral Venous Sinus Thrombosis After Posterior Fossa Tumor Surgery: Incidence, Risk Factors, and Therapeutic Options.

Cerebral venous sinus thrombosis (CVST) is a known complication of posterior fossa surgery near the sigmoid and transverse sinus. The incidence and treatment of postoperative asymptomatic CVST are controversial. To analyze incidence, risk factors, and management of asymptomatic postoperative CVST after posterior fossa tumor surgery. In this retrospective, single-center study, we included all patients who underwent posterior fossa tumor surgery in the semisitting position between January 2013 and December 2020. All patients underwent preoperative and postoperative imaging using MRI with/without additional computed tomography angiography. We analyzed the effect of demographic and surgical data on the incidence of postoperative CVST. Furthermore, therapeutic anticoagulation or conservative treatment for postoperative CVST and the incidence of intracranial hemorrhage were investigated. In total, 266 patients were included. Thirty-three of 266 (12.4%) patients developed postoperative CVST. All patients were asymptomatic. Thirteen of 33 patients received therapeutic anticoagulation, and 20 patients did not. Univariate analysis showed that age ( P = .56), sex ( P = .20), American Society of Anesthesiology status ( P = .13), body mass index ( P = .60), and length of surgery ( P = .176) were not statistically correlated with postoperative CVST. Multivariate analysis revealed that meningioma ( P < .001, odds ratio 11.3, CI 95% 4.1-31.2) and vestibular schwannoma ( P = .013, odds ratio 4.4, CI 95% 1.3-16.3) are risk factors for the development of new postoperative CVST. The use of therapeutic anticoagulation to treat postoperative CVST was associated with a higher rate of intracranial hemorrhage (n = 4, P = .017). Tumor entity influences the incidence of postoperative CVST. In clinically asymptomatic patients, careful decision making is necessary whether to initiate therapeutic anticoagulation or not.

Management of Acute Postoperative Bilateral Vocal Cords Paralysis after Surgical Resection of Posterior Fossa Tumor (Case Report)

Bilateral vocal cords paralysis is a serious condition that can be due to pathology of the vocal fold itself, damage to the cranial nerves ensuring their mobility, or central neurological disorders. In this article, we present a case of a 13-year-old girl who was admitted to the intensive care unit postoperatively for posterior cerebral fossa tumor surgery. She was reintubated after an extubation failure as a result of laryngeal dyspnea with stridor and chest in-drawing. The examination revealed damage to III, VI, and IX nerves with the immobility of vocal cords that were abducted towards the midline. A weaning tracheotomy was performed with a good clinical evolution and the patient was discharged 13 days after the surgery with maintained follow-ups. We report this case for its rarity.

Management of Pseudomeningocele Following Posterior Fossa Tumor Surgery in Children: A Single-Institution Experience in Egypt

Management of Pseudomeningocele Following Posterior Fossa Tumor Surgery in Children: A Single-Institution Experience in Egypt

Posterior fossa syndrome in a population of children and young adults with medulloblastoma: a retrospective, multicenter Italian study on incidence and pathophysiology in a histologically homogeneous and consecutive series of 136 patients.

Posterior fossa syndrome (PFS) is a set of debilitating complications that can occur after surgery for posterior fossa tumors. This study aimed to assess the preoperative radiological and surgical risk factors for the onset of PFS in a histologically homogeneous population of children with medulloblastoma and compare it to a similar population of young adults. Included patients underwent posterior fossa surgery for medulloblastoma at 11 Italian neurosurgical wards (2003-2019) and were referred to Fondazione IRCCS Istituto Nazionale dei Tumori in Milan (INT) for postoperative treatments. We collected patients' pre- and post-operative clinical, surgical and radiological data from the INT charts. To compare the distribution of variables, we used the Mann-Whitney and Fisher tests for continuous and categorical variables, respectively. 136 patients (109 children and 27 young adults) were included in the study. Among children, 29 (27%) developed PFS, and all of them had tumors at midline site with invasion of the fourth ventricle. Radiological evidence of involvement of the right superior (39% versus 12%; p = 0.011) or middle cerebellar peduncles (52% versus 18%; p = 0.002) seemed more common in children who developed PFS. Young adults showed an expected lower incidence of PFS (4 out of 27; 15%), that may be due to anatomical, physiological and oncological elements. This study confirmed some factors known to be associated with PFS onset and shed light on other debated issues. Our findings enhance an already hypothesized role of cerebellar language lateralization. The analysis of a population of young adults may shed more light on the often-neglected existence of PFS in non-pediatric patients.

Left-handedness should not be overrated as a risk factor for postoperative speech impairment in children after posterior fossa tumour surgery: a prospective European multicentre study.

Cerebellar mutism syndrome (CMS) is a severe neurological complication of posterior fossa tumour surgery in children, and postoperative speech impairment (POSI) is the main component. Left-handedness was previously suggested as a strong risk factor for POSI. The aim of this study was to investigate the relationship between handedness and the risk of POSI. We prospectively included children (aged < 18years) undergoing surgery for posterior fossa tumours in 26 European centres. Handedness was assessed pre-operatively and postoperative speech status was categorised as either POSI (mutism or reduced speech) or habitual speech, based on the postoperative clinical assessment. Logistic regression was used in the risk factor analysis of POSI as a dichotomous outcome. Of the 500 children included, 37 (7%) were excluded from the present analysis due to enrolment at a reoperation; another 213 (43%) due to missing data about surgery (n = 37) and/or handedness (n = 146) and/or postoperative speech status (n = 53). Out of the remaining 250 (50%) patients, 20 (8%) were left-handed and 230 (92%) were right-handed. POSI was observed equally frequently regardless of handedness (5/20 [25%] in left-handed, 61/230 [27%] in right-handed, OR: 1.08 [95% CI: 0.40-3.44], p = 0.882), also when adjusted for tumour histology, location and age. We found no difference in the risk of POSI associated with handedness. Our data do not support the hypothesis that handedness should be of clinical relevance in the risk assessment of CMS.