Altered functional connectivity in default mode network maintains attention task performance in school-age children with frontal lobe tumor.

This study examines functional brain network changes in children with frontal lobe tumors (FLT). Ten pediatric FLT patients from Beijing Tiantan Hospital and 20 healthy children were compared in terms of cognitive performance and resting-state functional magnetic resonance imaging (rs-fMRI) connectivity. The FLT group showed lower cognitive performance, particularly in visual and working memory domains, but had comparable attention abilities to the healthy controls. There were notable differences in connectivity between the default mode network (DMN) and sensorimotor network (SMN) in both groups. The FLT group also displayed a significant reduction in local efficiency in the left lateral parietal area within the DMN. Importantly, reduced DMN-SMN connections and increased DMN-lateral prefrontal cortex connectivity may facilitate maintaining attention and memory tasks in FLT children. This study sheds light on how the brains of children with FLT adapt, preserving "normal" attention functions despite frontal lobe damage.

Application of the CNS vital signs test and WISC-IV in the cognitive assessment of Chinese pediatric patients with intra-cranial space occupying lesion.

BACKGROUND: A fast and reliable neurocognitive assessment tool is required for pediatric patients with an intracranial space-occupying lesion (ICSOL). METHODS: A cross-sectional study was conducted on 41 pediatric patients having ICSOL. Cognitive abilities were assessed using both WISC-IV and CNS Vital Signs (CNS VS). All domains are compared to the normative data. Spearman's correlation analysis is performed between domains in two batteries. RESULTS: In the WISC-IV, CPI, PSI, and WMI are significantly lower than the normative level. In the CNS VS, NCI, Memory domains, Reaction Time, Social Acuity, and Sustained Attention are significantly lower. Six domains in the CNS VS, including Complex Attention, Sustained Attention, Cognitive Flexibility, Executive Function, Processing Speed, and Social Acuity, positively correlate to the PSI or CPI in the WISC-IV. Sixty percent (9/15) of domains in the CNS VS negatively correlate to the size of ISCOL. The FSIQ in the WISC-IV is significantly associated with patients' parent education level. CONCLUSION: Compared to the WISC-IV, CNS VS takes less time, but measures more domains. CNS VS is more sensitive to the size of ICSOL but is not affected by patients' parent education level. A healthy control group is warranted for interpreting the results in Chinese participants.

Postoperative Complications of Microscopic Fenestration for Middle Fossa Arachnoid Cysts: A Retrospective Study of 38 Cases and Literature Review.

INTRODUCTION: Middle fossa arachnoid cyst (MFAC) is one of the most common cranial cysts in children, and the various postoperative complications following cyst fenestration represent a major concern. We conducted a retrospective study in our department and performed a systematic review of the literature to identify the risk factors for complications. METHODS: A retrospective survey was conducted in 38 patients with MFAC (<14 years) who underwent microscopic fenestration from January 2019 to December 2020. Postoperative complications, including postoperative hemorrhage/hematoma, subdural hygroma (SH), cranial nerve palsy, postoperative central nervous system infection, and cerebrospinal fluid (CSF) leak, were collected. A systematic PubMed search for cohort studies on surgically treated MFAC published after 1980 was performed. The postoperative complications in the included studies were illustrated. RESULTS: The overall complication rate in our series was 7.9%, among whom, 9 patients (23.7%) developed postoperative SH, one of which required cyst-peritoneal shunting. Patients who developed SH were significantly younger (4.0 ± 1.8 vs. 6.3 ± 3.4 years, p = 0.012). Binary logistic analysis showed that a lower age could be a risk factor for developing SH (odds ratio: 0.738, p = 0.067). One patient developed a subdural hematoma. No cranial nerve palsy or CSF leak was observed. Eighteen studies were included in the systematic review, comprising 649 cases of MFAC. The most common complication was SH (4.9%), and the postoperative complication rates were similar between the microscopic and endoscopic techniques. CONCLUSION: The complication rate of MFAC fenestration is considerable. SH is the most common postoperative complication, and it mostly occurs in young children. Strict surgical indications should be applied for young children.

Changes in a sensorimotor network, occipital network, and psychomotor speed within three months after focal surgical injury in pediatric patients with intracranial space-occupying lesions.

BACKGROUND: Studies on cognition and brain networks after various forms of brain injury mainly involve traumatic brain injury, neurological disease, tumours, and mental disease. There are few related studies on surgical injury and even fewer pediatric studies. This study aimed to preliminarily explore the cognitive and brain network changes in children with focal, unilateral, well-bounded intracranial space-occupying lesions (ISOLs) in the short term period after surgery. METHODS: We enrolled 15 patients (6-14 years old) with ISOLs admitted to the Department of Pediatric Neurosurgery of the Beijing Tiantan Hospital between July 2020 and August 2021. Cognitive assessment and resting-state functional magnetic resonance imaging (rs-fMRI) were performed. Regional homogeneity (Reho), seed-based analysis (SBA) and graph theory analysis (GTA) were performed. Paired T-test was used for statistical analysis of cognitive assessment and rs-fMRI. Gaussian random-field theory correction (voxel p-value < 0.001, cluster p-value < 0.05) was used for Reho and SBA. False discovery rate correction (corrected p value < 0.05) for GTA. RESULTS: Our results showed that psychomotor speed decreased within three months after surgery. Further, rs-fMRI data analysis suggested that sensorimotor and occipital network activation decreased with low information transmission efficiency. CONCLUSION: We prudently concluded that the changes in cognitive function and brain network within three months after surgery may be similar to ageing and that the brain is vulnerable during this period.

A Numerical Simulation Method Considering Solid Phase Transformation and the Experimental Verification of Ti6Al4V Titanium Alloy Sheet Welding Processes.

A prediction model of the welding process of Ti-6Al-4V titanium alloy was established by using the finite element method, which was used to evaluate the phase composition, residual stress and deformation of the welded joints of Ti-6Al-4V sheets with different processes (including tungsten inert gas welding, TIG, and laser beam welding, LBW). The Ti-6Al-4V structures of TIG welding and LBW are widely used in marine engineering. In order to quantitatively study the effects of different welding processes (including TIG welding and LBW) on the microstructure evolution, macro residual stress and deformation of Ti6Al4V titanium alloy sheets during welding, a unified prediction model considering solid-state phase transformation was established based on the ABAQUS subroutine. In this paper, LBW and TIG welding experiments of 1.6 mm thick Ti-6Al-4V titanium alloy sheets were designed. The microstructure distribution of the welded joints observed in the experiment was consistent with the phase composition predicted by the model, and the hardness measurement experiment could also verify the phase composition and proportion. From the residual stress measured by experiment and the residual stress and deformation calculated by finite element simulation of LBW and TIG weldments, it is concluded that the effect of phase transformation on residual stress is mainly in the weld area, which has an effect on the distribution of tensile and compressive stress in the weld area. The overall deformation of the welded joint is mainly related to the welding process, and the phase transformation only affects the local volume change of the weld seam. Importantly, the phase composition and residual stress, which are scalar fields, calculated by the established model can be introduced into the numerical analysis of structural fracture failure as input influence factors.

The truths behind the statistics of surgical treatment for hypertensive brainstem hemorrhage in China: a review.

Hypertensive brainstem hemorrhage (HBSH) is of high morbidity and mortality rate. But many clinical studies were written in Chinese and had not been reviewed. A systemic review of Chinese clinical studies for HBSH was performed. A systemic literature search in PubMed, Web of Science, China National Knowledge Infrastructure, and Weipu database and Wanfang database up to March 2020 was performed. Clinical control studies including a surgical evacuation (SE) group and a conservative management (CM) group were included. The clinical outcome and mortality rate were compared. Ten cohort studies were included, involving 944 participants (304 in the SE group and 640 in the CM group). All included patients were comatose, with the average age ranged from 45 to 65 years old. Among five studies using mRS or GOS as outcome score, a total of 16.6% (89/535) of patients achieve self-maintenance with minor disabilities, including 26.8% (34/127) in the SE group and 13.5% (55/408) in the CM group. The overall mortality rate in the SE group was 27.6%, ranged from 9.3 to 60% among different studies. The overall mortality rate in the CM group was 60.6%, ranged from 18.5 to 100.0%. Elder and comatose HBSH patients are not contraindicated for surgery. The review showed that this group of patients obtained a better outcome and lower mortality rate after surgical treatment. The quality of included studies was relatively low, but a high-level clinical study on HBSH is of great difficulty, as both clinicians and patients faced various sociological issues rather than pure medical problems.

Predictive Factors of Postoperative Peritumoral Brain Edema after Meningioma Resection.

BACKGROUND: Postoperative peritumoral brain edema (PTBE) is the progressively exacerbating cerebral edema following meningiomas resection. OBJECTIVE: The study aims to identify the predictive factors of postoperative PTBE. MATERIALS AND METHODS: A retrospective study was conducted on the 117 cases of patients who underwent meningioma. The histopathological features of the tumors were re-assessed according to WHO 2016 classification. Clinical and pathohistological features were analyzed. RESULTS: Thirteen patients (11.1%) were diagnosed having postoperative PTBE. Preoperative seizure (odds ratio [OR] = 6.125, P = 0.039) and histological prominent nucleoli (OR = 3.943, P = 0.039) were the independent risk factors for postoperative PTBE. Meningiomas with a parietal localization were more likely to develop postoperative PTBE (OR = 3.576, P = 0.054). Brain invasion and large tumor volume did not increase complication rate. Preoperative edema index was significantly higher in brain invasive meningiomas (3.0 ± 2.2 versus 1.8 ± 1.7, P = 0.001). Patients having moderate preoperative PTBE were prone to the complication (21.4% versus 7.9%, P = 0.100). CONCLUSIONS: Preoperative seizure were the predictive factors for postoperative PTBE. Careful venous protection during the operation may be helpful, especially for tumors locating in the parietal lobe. Prominent nucleoli observed in postoperative pathology should warrant surgeons' attention. Comprehensive perioperative management is essential for these patients.

Spinal arachnoiditis followed by intrathecal tigecycline therapy for central nervous system infection by extremely drug-resistant Acinetobacter baumannii.

In prior research, intrathecal tigecycline was successfully used to treat central nervous system infection by extensively drug-resistant Acinetobacter baumannii. However, little is known about its safe dose and adverse reactions. This study reports the case of a 28-year-old male patient who was diagnosed with central nervous system infection by extensively drug-resistant A. baumannii after the removal of a ventriculoperitoneal shunt. Intravenous and intrathecal tigecycline were administrated simultaneously. Spinal arachnoiditis was discovered after nine doses of intrathecal tigecycline. Spinal arachnoiditis was resolved after discontinuation of the antibiotic. This is the first report of an adverse reaction to intrathecal tigecycline. The case was complicated by spinal arachnoiditis, which obstructed the assessment of cerebrospinal fluid. The appropriate dose and administration schedule of intrathecal tigecycline remain to be determined.

Shifting subdural fluid collection and hydrocephalus after foramen magnum decompression for basilar invagination.

Background: Postoperative hydrocephalus and subdural fluid collection (SFC) have been reported as the rare complications following foramen magnum decompression in patients with Chiari malformation.Case Description: The paper reports the case of a 63-year-old female patient who underwent foramen magnum decompression for basilar invagination. The patient developed a shifting, bilateral SFC and subsequent acute hydrocephalus. A ventriculoperitoneal shunting was performed and the clinical symptom resolved. The dramatic change in CSF distribution supported the diagnosis of external hydrocephalus, which was associated with a postoperative cervical pseudomeningocele.Conclusions: Postoperative SFC in patients underwent foramen magnum decompression may harbor different mechanisms. Subdural drainage for patients having external hydrocephalus may have a higher recurrence rate.

Impact of Surgeon Experience on Postoperative Rehemorrhage in Spontaneous Basal Ganglia Intracerebral Hemorrhage.

BACKGROUND: Spontaneous intracerebral hemorrhage (SICH) is of high mortality and morbidity. SICH in the basal ganglia is usually attributed to chronic hypertension. Postoperative rehemorrhage is a severe complication, and it is relative to surgical techniques. METHODS: A retrospective survey was conducted on 123 patients with basal ganglia SICH who received surgery from January 2015 to January 2019. Postoperative rehemorrhage within 24 hours was recorded. Preoperative clinical parameters, surgeon experience (<10 and >20 years), operation time, surgical approach, and hemostasis technique were recorded and analyzed. RESULTS: The total postoperative rehemorrhage rate was 12.2% (15/123). The univariable analysis showed general surgeons had a higher postoperative rehemorrhage rate than experienced surgeons (30.4% vs. 8.6%, respectively; P = 0.068). The operation time (minutes) in experienced surgeons was significantly longer (164.9 ± 53.5 vs. 137.7 ± 30.8, P = 0.016), but they had a higher chance to locate the responsible vessel (74.2% vs. 40.0%, P = 0.001), respectively. Logistic analysis indicated that experienced surgeons significantly reduced the risk of rehemorrhage (odds ratio [OR], 0.242; P = 0.021). Transsylvian approach was a protective factor for postoperative rehemorrhage (OR, 0.291; P = 0.045). CONCLUSIONS: Surgeons' experience plays the most important role in postoperative rehemorrhage. Surgeons with rich experience were willing to spend more time to achieve definitive hemostasis in operation. The use of a transsylvian approach can significantly reduce the rehemorrhage rate. Packing hemostasis with gelatin sponge may increase complications.

Complications in Staged Late Titanium Cranioplasty and Ventriculoperitoneal Shunting for Patients with Traumatic Brain Injury.

BACKGROUND: Hydrocephalus is a common complication following decompressive craniectomy. Ventriculoperitoneal shunt (VPS) is required for some patients before receiving a cranioplasty (CP). The presence of a VPS is regarded as a risk factor for overall CP complications. METHODS: A retrospective survey was conducted on 176 patients with traumatic brain injury who underwent late (>3 months) titanium CP (Ti-CP) in our hospital from April 2014 to July 2018. Thirteen patients (7.4%) had preoperative VPS. Propensity score matching was performed for these 13 patients with a ratio of 1:5. A total of 78 patients were selected. Preoperative clinical parameters and postoperative complications were analyzed. The period of postoperative follow-up ranged from 3 to 63 months (mean 21.3 ± 17.0 months). RESULTS: The overall complication rate was greater in the VPS group (P = 0.010). These patients were more likely to develop a sunken skin flap (P < 0.001). The rate of postoperative cerebral hemorrhage was greater in the VPS group. Logistic analysis showed that preoperative VPS was an independent risk factor for postoperative extradural collection (odds ratio 17.714, P < 0.001). VPS was not related to postoperative infection and seizure. Postoperative drainage duration longer than 2.5 days significantly increased the risk of postoperative infection (odds ratio 7.715, P = 0.023). CONCLUSIONS: The presence of a VPS significantly increased the risk of extradural collection in patients with traumatic brain injury who underwent late Ti-CP. It also was related to postoperative hemorrhage. The sunken skin flap in patients with VPS increased surgical difficulty and the likelihood of extradural accumulation. Preoperative VPS was not related to postoperative infection and seizure in Ti-CP.

Excessive Hemostasis on the Scalp Increases Superficial Surgical Site Infection Rate in Cranioplasty.

BACKGROUND: Cranioplasty is a routine procedure, but it carries a significantly higher complication rate over standard clean cranial surgery. Surgical site infection is the most common but severe complication. Risk factors for surgical site infection are still debated. METHODS: A retrospective survey of 155 patients (≥16 years old) who exclusively underwent customized titanium cranioplasty from April 2014 to January 2017 was performed. Preoperative clinical parameters, surgeon's hemostasis technique, temporalis dissection, operative time, intraoperative blood loss, postoperative catheter duration and drainage, postoperative hemorrhage and extradural fluid collection (EDFC), and prophylactic antibiotics were recorded and compared between patients with superficial surgical site infection (sSSI) and patients with non-sSSI. RESULTS: Overall sSSI rate was 10.3%. Binary logistic analysis showed excessive hemostasis on scalp (odds ratio = 10.302, P = 0.000), presence of postoperative EDFC (odds ratio = 12.740, P = 0.003), and postoperative drainage >277 mL (odds ratio = 10.302, P = 0.000) were independent risk factors for sSSI. Patients who received excessive hemostasis had a longer operative time (P = 0.000). A flaccid cranial defect was a protective factor for postoperative EDFC (odds ratio = 0.130, P = 0.044), whereas presence of ventriculoperitoneal shunt could induce EDFC formation (odds ratio = 9.598, P = 0.020). Postoperative subgaleal drainage was correlated to the size of cranial defect (standardized ß = 0.347, P = 0.000). Timing of cranioplasty and use of prophylactic antibiotics were not related to sSSI. CONCLUSIONS: Surgeons should lower the hemostasis standard for cranioplasty, as this would promote wound healing and reduce operative time, which subsequently decreases SSI rate.

Bilateral External Ventricular Drains Increase Ventriculostomy-Associated Cerebrospinal Fluid Infection in Low Modified Graeb Score Intraventricular Hemorrhage.

BACKGROUND: Ventriculostomy-associated cerebrospinal fluid infection (VAI) is a major complication limiting the use of an external ventricular drain (EVD) in treating patients with intraventricular hemorrhage (IVH). Risk factors of VAI are still under wide discussion. METHODS: We performed a retrospective review of 84 patients with IVH who underwent EVD at our center between January 2012 and January 2017. Preoperative clinical parameters, surgeon status, number of catheters and catheter-days, subgaleal tunneling distance, frequency of urokinase flush, and prophylactic antibiotics were compared between the infective and noninfective groups. RESULTS: The overall rate of VAI was 31.0%. Univariate analysis showed a higher modified Graeb Score (mGS), higher proportion of bilateral catheters, and longer hospital stay in patients with VAI. Binary logistic analysis of all clinical factors identified high mGS (≥16) as an independent risk factor for VAI (odds ratio, 3.242; P = 0.026). Among operative and postoperative factors, the use of bilateral catheters significantly contributed to VAI (odds ratio, 4.211; P = 0.031), but a subgroup comparison showed an increased VAI rate only in the low mGS group (mGS <15). No VAI occurred in patients with a single EVD in the low mGS group. Catheter-days and multiple urokinase flushes were not related to VAI. CONCLUSIONS: Patients with a high mGS are vulnerable to VAI. Bilateral EVD may be an appropriate treatment option for patients with a high mGS, but might increase the risk of infection in those with a low mGS.

Neuroendoscopic endonasal management of cerebrospinal fluid rhinorrhea.

Neuroendoscopic endonasal approach has gained popularity in managing traumatic, spontaneous, and especially iatrogenic cerebrospinal fluid (CSF) rhinorrhea. The authors examined 8 patients presenting with CSF rhinorrhea between December 2012 and June 2014: 5 patients had iatrogenic leak, 2 patients had traumatic leak, and 1 patient had a spontaneous onset of CSF rhinorrhea. Sites of the CSF leaks were detected through computed tomographic cisternography and magnetic resonance imaging in the patients with traumatic and spontaneous leaks. All patients received neuroendoscopic endonasal surgery for the CSF leak. The largest defect was 22 mm in maximum diameter. Endoscopic supraciliary "keyhole" approach was performed in 1 patient after confirmation of a frontal sinus leak using the endoscopic endonasal approach. The success rate was 100% in the first attempt. Follow-up period ranged from 3 to 24 months, and no recurrence was reported. Identifying the leak site and choosing the appropriate surgical technique remain the most important factor in surgical success.