Double concentric craniotomy: Safe and effective technique to achieve an en bloc resection of tumor involving both skull and duraa

AbstractIntroductionMany tumors can involve the skull. Meningiomas are one of the most common intracranial neoplasms and invasion of the bone was described in 49% of cases. Other neoplastic lesions that can arise in bone, or involve it, are metastases, hemangiomas, aggressive cutis carcinomas and sarcomas. Radical excision is the golden standard of treatment but elevating a bone flap when the tumor involves both the skull and the dura could represent a technical challenge.Presentation of caseWe report the technical details of our approach to remove a meningioma involving both skull and dura in a man aged 45. Patient underwent gross total excision and cranioplasty with PEEK custom made prothesis (Synthes™).DiscussionWe describe a double concentric craniotomy (DCC) technique where the tumor involving the bone is before left in situ, exposing normal dura, to perform afterwards en-bloc excision with minimal traction of brain surface.ConclusionDCC is a safe and effective technique to remove tumor involving both skull and dural structures under direct vision

The efficacy of trabecular titanium cages to Induce reparative bone activity after lumbar arthrodesis studied through the 18f-Naf PET/CT scan: observational clinical in-vivo study

Background: Titanium trabecular cages (TTCs) are emerging implants designed to achieve immediate and long-term spinal fixation with early osseointegration. However, a clear radiological and clinical demonstration of their efficacy has not yet been obtained. The purpose of this study was to evaluate the reactive bone activity of adjacent plates after insertion of custom-made titanium trabecular cages for the lumbar interbody with positron emission tomography (PET)/computed tomography (CT) 18F sodium fluoride (18F-NaF). Methods: This was an observational clinical study that included patients who underwent surgery for degenerative disease with lumbar interbody fusion performed with custom-made TTCs. Data related to the metabolic-reparative reaction following the surgery and its relationship with clinical follow-up from PET/CT performed at different weeks were evaluated. PET/CTs provided reliable data, such as areas showing abnormally high increases in uptake using a volumetric region of interest (VOI) comprising the upper (UP) and lower (DOWN) limits of the cage. Results: A total of 15 patients was selected for PET examination. Timing of PET/CTs ranged from one week to a maximum of 100 weeks after surgery. The analysis showed a negative correlation between the variables SUVmaxDOWN/time (r = −0.48, p = 0.04), ratio-DOWN/time (r = −0.53, p = 0.02), and ratio-MEAN/time (r = −0.5, p = 0.03). Shapiro−Wilk normality tests showed significant results for the variables ratio-DOWN (p = 0.002), ratio-UP (0.013), and ratio-MEAN (0.002). Conclusions: 18F-NaF PET/CT has proven to be a reliable tool for investigating the metabolic-reparative reaction following implantation of TTCs, demonstrating radiologically how this type of cage can induce reparative osteoblastic activity at the level of the vertebral endplate surface. This study further confirms how electron-beam melting (EBM)-molded titanium trabecular cages represent a promising material for reducing hardware complication rates and promoting fusion

Risk of Recurrence of Chronic Subdural Hematomas After Surgery: A Multicenter Observational Cohort Study

Background: Chronic Subdural Hematoma (CSDH) is a common condition in the elderly population. Recurrence rates after surgical evacuation range from 5 to 30%. Factors predicting recurrence remain debated and unclear. Objective: To identify factors associated with increased risk of recurrence. Methods: Cases of CSDHs that underwent surgical treatment between 2005 and 2018 in the Neurosurgery Units of two major Italian hospitals were reviewed. Data extracted from a prospectively maintained database included demographics, laterality, antithrombotic therapy, history of trauma, corticosteroid therapy, preoperative and postoperative symptoms, type of surgical intervention, use of surgical drain, and clinical outcomes. Results: A total of 1313 patients was analyzed. The overall recurrence rate was 10.1%. The risk of recurrence was not significantly different between patients with unilateral or bilateral CSDH (10.4 vs. 8.8%, p = 0.39). The risk of recurrence was higher in patients that underwent surgical procedure without postoperative drainage (16.1 vs. 5.4%, p < 0.01). No relationship was found between recurrence rates and therapy with antithrombotic drugs (p = 0.97). The risk of recurrence was increasingly higher considering craniostomy, craniectomy, and craniotomy (9.3, 11.3, and 18.9%, respectively, p = 0.013). Lower recurrence rates following Dexamethasone therapy were recorded (p = 0.013). Conclusion: No association was found between the risk of recurrence of CSDH after surgical evacuation and age, use of antithrombotic medication, or laterality. Burr-hole craniostomy was found to be associated with lower recurrence rates, when compared to other surgical procedures. Placement of surgical drain and Dexamethasone therapy were significantly associated with reduced risk of recurrence of CSDHs

Let me see: Correlation between 5-ala fluorescence and molecular pathways in glioblastoma: A single center experience

Background: Despite the aggressiveness of multimodal treatment, glioblastoma (GBM) is still a challenge for neurosurgeons, neurooncologists, and radiotherapists. A surgical approach is still a cornerstone in GBM therapeutic management, as the extent of resection is strongly related both to overall survival and progression-free survival. From this perspective, the use of photodynamic molecules could represent an interesting tool to achieve maximal and safe resection. Being able to trace the lesion’s edges, indeed, could allow to improve the extent of resection and to minimize residual tumor while sparing normal tissue. The use of 5-aminolevulinic acid (5-ALA) as a photodynamic tracer is well established due to its strict correlation both with cellularity and metabolic activity of the GBM cell clones. Objective: Our study aims to define whether a different molecular asset of GBM (especially investigating IDH 1/2 mutation, proliferation index, and MGMT promoter methylation) results in different fluorescence expression, possibly because of differences in metabolic pathways due to different genotypes. Methods: Patients undergoing surgery for GBM removal at our Institute (Dep. Of Neurosurgery, Ospedale Città della Salute e della Scienza, University of Turin, Italy) were retrospectively reviewed. Patients with histological diagnosis confirmation and to whom 5-ALA was given before surgery were included. The whole surgical procedure was recorded and then analyzed by three different people (a medical student, a resident, and a senior surgeon with an interest in neurooncology and experience in using 5-ALA) and a score was assigned to the different degrees of intraoperative fluorescence. The degree of fluorescence was then matched with the genotype. Results: A trend of grade 2 fluorescence (i.e., ”strong”) was observed in the IDH 1/2 wild-type (WT) genotype, suggesting a more intense metabolic activity in this particular subgroup, while, no or weak fluorescence was observed more often in the IDH 1/2 mutated tumors, suggesting a lower metabolic activity. No relations were found between fluorescence grade and MGMT promoter methylation or, interestingly, cellularity. As a secondary analysis, more epileptogenicity of the IDH 1/2 mutated GBM was noticed, similarly to other recent literature. Conclusion: Our results do not support the use of 5-ALA as a diagnostic tool, or a way to substitute the molecular profiling, but confirm 5-ALA as a powerful metabolic tracer, able to easily detect the pathological cells, especially in the IDH WT genotype, and in this perspective, further studies will be necessary to better describe the metabolic activity of GBM cells

Clinical outcomes, MRI evaluation and predictive factors of indirect decompression with lateral transpsoas approach for lumbar interbody fusion: a multicenter experience

Introduction: Evaluating the effects of indirect decompression obtained through lateral lumbar interbody fusion (LLIF) by clinical improvements and radiological parameters on MRI scans. Identifying predictors of better decompression and clinical outcome. Materials and methods: From 2016 to 2019, patients who underwent single- or double-level indirect decompression LLIF were consecutively reviewed. Radiological signs of indirect decompression were evaluated in preoperative and follow-up MRI studies and were subsequently correlated to clinical data, expressed as axial/radicular pain (VAS back/leg), index of disability (Oswestry Disability Index) and clinical severity of lumbar stenosis (Swiss Spinal Stenosis Questionnaire). Results: 72 patients were enrolled. The mean follow-up was 24 months. Differences in vertebral canal area (p < 0.001), height of the foramina (p < 0.001), thickness of the yellow ligament (p = 0.001) and anterior height of the interbody space (p = 0.02) were observed. Older age (p = 0.042), presence of spondylolisthesis (p = 0.042), presence of intra-articular facet effusion (p = 0.003) and posterior height of the implanted cage (p = 0.020) positively affected the increase of the canal area. Change in root canal area (p < 0.001), height of the implanted cage (p = 0.020) and younger age (p = 0.035) were predictive factors of root pain relief, while increased vertebral canal area (p = 0.020) and height of the interbody fusion cage (p = 0.023) positively affected the severity of clinical stenosis. Conclusions: LLIF indirect decompression showed both clinical and radiological improvements. Presence and degree of spondylolisthesis, presence of intra-articular facet effusion, age of the patient and height of the cage were predictive factors of major clinical improvements

A high-performance matrix-matrix multiplication methodology for CPU and GPU architectures

Current compilers cannot generate code that can compete with hand-tuned code in efficiency, even for a simple kernel like matrix–matrix multiplication (MMM). A key step in program optimization is the estimation of optimal values for parameters such as tile sizes and number of levels of tiling. The scheduling parameter values selection is a very difficult and time-consuming task, since parameter values depend on each other; this is why they are found by using searching methods and empirical techniques. To overcome this problem, the scheduling sub-problems must be optimized together, as one problem and not separately. In this paper, an MMM methodology is presented where the optimum scheduling parameters are found by decreasing the search space theoretically, while the major scheduling sub-problems are addressed together as one problem and not separately according to the hardware architecture parameters and input size; for different hardware architecture parameters and/or input sizes, a different implementation is produced. This is achieved by fully exploiting the software characteristics (e.g., data reuse) and hardware architecture parameters (e.g., data caches sizes and associativities), giving high-quality solutions and a smaller search space. This methodology refers to a wide range of CPU and GPU architectures