Does reintervention improve survival in recurrent glioblastoma? Facing a temporal bias in the literature.

BACKGROUND: Glioblastoma (GBM) is the most frequent intraaxial malignant brain tumour, in which recurrence management is a frequent and demanding issue. Recently, reintervention has emerged as a useful tool for treatment. However, some new evidence has shown that most of the articles published could have overestimated its effects. We aimed to analyse the effect on survival of reintervention considering it as a time-dependent variable and to compare it with classic statistical analysis. METHODS: We performed a retrospective study with GBM patients between 2007 and 2017. We compared the overall survival (OS) between reintervention and non-reintervention groups with time-dependent statistical methods (Simon-Makuch and landmarking methods and time-dependent multivariable Cox analysis) and compared them with those obtained with non-dependent time variable analysis. RESULTS: A total of 183 patients were included in the analysis and 44 of them were reoperated. The standard analysis with Kaplan-Meier and multivariable Cox regression of the cohort showed an OS of 22.2 months (95% CI 12.56-16.06) in the reintervention group and 11.8 months (95% CI 9.87-13.67) in the non-reintervention group (p < .001); and an HR 0.649 (95% CI 0.434-0.97 p = .035) for reintervention, demonstrating an increase in OS. However, time-dependent analysis with the Simon-Makuch test and the landmarking method showed that the relationship was not consistent, as this increase in OS was not significant. Moreover, time-dependent multivariable Cox analysis did not show that reintervention improved OS in our cohort (HR 0.997 95% CI 0.976-1.018 p = 0.75). CONCLUSIONS: There has been a temporal bias in the literature that has led to an overestimation of the positive effect of reintervention in recurrent GBM. However, reintervention could still be useful in some selected patients, who should be individualized according to prognostic factors related to the patient, biology of the tumour, and characteristics of surgical procedure.

How I do it? Lumbar cortical bone trajectory fixation with image-guided neuronavigation.

BACKGROUND: Cortical bone trajectory was described in 2009 to reduce screw loosening in osteoporotic patients. Since then, it has demonstrated improvements in biomechanical and perioperative results compared to pedicle screws, and it have been described as a minimally invasive technique. METHOD: We describe our experience with the technique assisted by 3D neuronavigation and review some of the complications and tools to avoid them together with limitations and pitfalls. CONCLUSION: Cortical bone trajectory guided by 3D neuronavigation helps to reduce the need for radiation and incidence of complications.

[The 2013 Sixto Obrador Award. A triple-axis topographical model for surgical planning of craniopharyngiomas. Part I: historical review of the topographical diagnosis and classification schemes of craniopharyngiomas]. / Premio Sixto Obrador 2013. Modelo topográfico de 3 ejes para el tratamiento quirúrgico de los craneofaringiomas. Parte I: Evolución histórica del diagnóstico topográfico y métodos de clasificación de los craneofaringiomas.

INTRODUCTION AND OBJECTIVES: This study reviews the historical evolution of pathological, neuroradiological and surgical evidence that influenced the topographical concepts and classification schemes of craniopharyngiomas. MATERIAL AND METHODS: An extensive, systematic analysis of the surgical series of craniopharyngiomas reported in the literature was performed (n=145 series, 4,588 tumours) to describe the fundamental anatomical findings guiding the topographical classification schemes used for this tumour throughout history. These findings were compared with topographical relationships reported for well-described operated craniopharyngiomas (n=224 cases) as well as for non-operated cases studied in autopsies (n=201 cases). RESULTS: Two major variables define the topography of a craniopharyngioma: its position relative to the sellar diaphragm and its degree of invasion of the third ventricle floor. Suprasellar lesions displacing the third ventricle floor upwards (pseudointraventricular craniopharyngiomas) are amenable to safe, radical resection and must be differentiated from lesions developing primarily within the third ventricle floor (infundibulo-tuberal or not strictly intraventricular craniopharyngiomas). The latter group typically shows tight, circumferential adhesion to the third ventricle floor and represents approximately 40% of all cases. CONCLUSIONS: A triple-axis topographical model for craniopharyngiomas that includes the degree of hypothalamus invasion is useful in planning surgical approach and degree of resection. The group of infundibulo-tuberal craniopharyngiomas associates the highest risk of hypothalamic injury (50%). The endoscopically-assisted extended transsphenoidal approach provides a proper view to assess the topography of the craniopharyngioma and its degree of adherence to the hypothalamus.

[The 2013 Sixto Obrador Award. A triple-axis topographical model for surgical planning of craniopharyngiomas. Part II: Anatomical and neuroradiological evidence to define triple-axis topography and its usefulness in predicting individual surgical risk]. / Premio Sixto Obrador 2013. Modelo topográfico de 3 ejes para el tratamiento quirúrgico de los craneofaringiomas. Parte II: Evidencias anatómicas y neurorradiológicas que definen el modelo de clasificación de 3 ejes y su utilidad para predecir el riesgo quirúrgico individual.

INTRODUCTION AND OBJECTIVES: This study evaluates the pathological and magnetic resonance imaging evidence to define the precise topographical relationships of craniopharyngiomas and to classify these lesions according to the risks of hypothalamic injury associated with their removal. MATERIAL AND METHODS: An extensive, systematic analysis of the topographical classification models used in the surgical series of craniopharyngiomas reported in the literature (n=145 series, 4,588 craniopharyngiomas) was performed. Topographical relationships of well-described operated craniopharyngiomas (n=224 cases) and of non-operated cases reported in autopsies (n=201 cases) were also analysed. Finally, preoperative and postoperative magnetic resonance imaging studies displayed in craniopharyngiomas reports (n=130) were compared to develop a triple-axis model for the topographical classification of these lesions with qualitative information regarding the associated risk of hypothalamic injury. RESULTS: The 2 major variables with prognostic value to define the topography of a craniopharyngioma are its position relative to the sellar diaphragm and its degree of invasion of the third ventricle floor. A multivariate diagnostic model including 5 variables -patient age, presence of hydrocephalus and/or psychiatric symptoms, the relative position of the hypothalamus and the mammillary body angle- makes it possible to differentiate suprasellar craniopharyngiomas displacing the third ventricle upwards (pseudointraventricular craniopharyngiomas) from either strictly intraventricular craniopharyngiomas or lesions developing primarily within the third ventricle floor (infundibulo-tuberal or not strictly intraventricular craniopharyngiomas). CONCLUSIONS: A triple-axis topographical model for craniopharyngiomas that includes the degree of hypothalamus invasion is useful in planning the surgical approach and degree of resection. Infundibulo-tuberal craniopharyngiomas represent 42% of all cases. These lesions typically show tight, circumferential adhesion to the third ventricle floor, with their removal being associated with a 50% risk of hypothalamic injury. The endoscopically-assisted extended transsphenoidal approach provides a proper view to assess the degree and extension of craniopharyngioma adherence to the hypothalamus.

Patients awaiting surgery for neurosurgical diseases during the first wave of the COVID-19 pandemic in Spain: a multicentre cohort study.

OBJECTIVES: The large number of infected patients requiring mechanical ventilation has led to the postponement of scheduled neurosurgical procedures during the first wave of the COVID-19 pandemic. The aims of this study were to investigate the factors that influence the decision to postpone scheduled neurosurgical procedures and to evaluate the effect of the restriction in scheduled surgery adopted to deal with the first outbreak of the COVID-19 pandemic in Spain on the outcome of patients awaiting surgery. DESIGN: This was an observational retrospective study. SETTINGS: A tertiary-level multicentre study of neurosurgery activity between 1 March and 30 June 2020. PARTICIPANTS: A total of 680 patients awaiting any scheduled neurosurgical procedure were enrolled. 470 patients (69.1%) were awaiting surgery because of spine degenerative disease, 86 patients (12.6%) due to functional disorders, 58 patients (8.5%) due to brain or spine tumours, 25 patients (3.7%) due to cerebrospinal fluid (CSF) disorders and 17 patients (2.5%) due to cerebrovascular disease. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was mortality due to any reason and any deterioration of the specific neurosurgical condition. Second, we analysed the rate of confirmed SARS-CoV-2 infection. RESULTS: More than one-quarter of patients experienced clinical or radiological deterioration. The rate of worsening was higher among patients with functional (39.5%) or CSF disorders (40%). Two patients died (0.4%) during the waiting period, both because of a concurrent disease. We performed a multivariate logistic regression analysis to determine independent covariates associated with maintaining the surgical indication. We found that community SARS-CoV-2 incidence (OR=1.011, p<0.001), degenerative spine (OR=0.296, p=0.027) and expedited indications (OR=6.095, p<0.001) were independent factors for being operated on during the pandemic. CONCLUSIONS: Patients awaiting neurosurgery experienced significant collateral damage even when they were considered for scheduled procedures.

Long term outcome and fusion rate of transdiscal fixation for L5-S1 high grade spondylolisthesis.

OBJECTIVE: High grade spondylolisthesis (HGS) is a quite rare entity and many techniques are available to address this condition. In 1994 Abdu et al. proposed a transdiscal fixation approach that achieved a good clinical outcome. We analyse outcome and fusion achieved in patients treated by transdiscal fixation after 1-year follow-up. METHODS: We reviewed patients operated through transdiscal fixation since 2014 with a follow-up of at least 1 year, and compared preoperative and postoperative clinical measures (ODI, VAS and EQ-5D) and postoperative complications. Also, we analyzed the degree of fusion on CT scan with Lenke and Birdwell criteria. RESULTS: Twelve patients were included in the study with a mean follow-up of 49.4 months (range 12.8-84.1 months). Three cases presented a Meyerding grade IV spondylolisthesis and 9 cases grade III. At 1-year follow-up mean postoperative ODI, VAS and EQ5D scores improved (ODI 13.2 (range 0-30) vs 49.83 (range 15-71.1); p = .005). Equally this improvement was seen in the last follow-up (ODI 9.28 (range 0-35) vs 49.83 (range 15-71.1); p = .005). CT scan showed fusion grade A in 5 patients (41.6%), another 5 as grade B (41.6%) in Lenke classification. According to the Birdwell criteria 4 patients were classified as grade I (33.3%), 7 patients grade II (58.3%). None showed complications postoperatively or radiolucency in follow-up. CONCLUSIONS: Transdiscal fixation shows a good clinical outcome that is maintained throughout a long time period and provides a reliable and suitable fusion.

Simulation with 3D Neuronavigation for Learning Cortical Bone Trajectory Screw Placement.

BACKGROUND AND OBJECTIVE: Learning a new technique in neurosurgery is a big challenge especially for trainees. In recent years, simulations and simulators got into the focus as a teaching tool. Our objective is to propose a simulator for placement of cortical bone trajectory (CBT) screws to improve results and reduce complications. METHODS: We have created a platform consisting of a sawbone navigated with a 3D fluoroscope to familiarize our trainees and consultants with CBT technique and later implement it in our department. Objective Structured Assessment of Technical Skills (OSATS) and Physician Performance Diagnostic Inventory Scale (PPDI) were obtained before and after the use of the simulator by the five participants in the study. Patients who were operated on after the implementation of the technique were retrospectively reviewed. RESULTS: During the simulation, there were 4 cases of pedicle breach out of 24 screws inserted (16.6%). After having completed simulation, participants demonstrated an improvement in OSATS and PPDI (p = 0.039 and 0.042, respectively). Analyzing the answers to the different items of the tests, participants mainly improved in the knowledge (p = 0.038), the performance (p = 0.041), and understanding of the procedure (p = 0.034). In our retrospective series, eight patients with L4-L5 instability were operated on using CBT, improving their Oswestry Disability Index (ODI) score (preoperative ODI 58.5 [SD 16.7] vs. postoperative ODI 31 [SD 13.4]; p = 0.028). One intraoperative complication due to a dural tear was observed. In the follow-up, we found a case of pseudoarthrosis and a facet joint violation, but no other complications related to misplacement, pedicle fracture, or hardware failure. CONCLUSION: The simulation we have created is useful for the implementation of CBT. In our study, consultants and trainees have valued very positively the learning obtained using the system. Moreover, simulation facilitated the learning of the technique and the understanding of surgical anatomy. We hope that simulation helps reducing complications in the future.

Impact of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients: a nationwide study in Spain.

OBJECTIVE: To assess the effect of the first wave of the SARS-CoV-2 pandemic on the outcome of neurosurgical patients in Spain. SETTINGS: The initial flood of COVID-19 patients overwhelmed an unprepared healthcare system. Different measures were taken to deal with this overburden. The effect of these measures on neurosurgical patients, as well as the effect of COVID-19 itself, has not been thoroughly studied. PARTICIPANTS: This was a multicentre, nationwide, observational retrospective study of patients who underwent any neurosurgical operation from March to July 2020. INTERVENTIONS: An exploratory factorial analysis was performed to select the most relevant variables of the sample. PRIMARY AND SECONDARY OUTCOME MEASURES: Univariate and multivariate analyses were performed to identify independent predictors of mortality and postoperative SARS-CoV-2 infection. RESULTS: Sixteen hospitals registered 1677 operated patients. The overall mortality was 6.4%, and 2.9% (44 patients) suffered a perioperative SARS-CoV-2 infection. Of those infections, 24 were diagnosed postoperatively. Age (OR 1.05), perioperative SARS-CoV-2 infection (OR 4.7), community COVID-19 incidence (cases/105 people/week) (OR 1.006), postoperative neurological worsening (OR 5.9), postoperative need for airway support (OR 5.38), ASA grade ≥3 (OR 2.5) and preoperative GCS 3-8 (OR 2.82) were independently associated with mortality. For SARS-CoV-2 postoperative infection, screening swab test <72 hours preoperatively (OR 0.76), community COVID-19 incidence (cases/105 people/week) (OR 1.011), preoperative cognitive impairment (OR 2.784), postoperative sepsis (OR 3.807) and an absence of postoperative complications (OR 0.188) were independently associated. CONCLUSIONS: Perioperative SARS-CoV-2 infection in neurosurgical patients was associated with an increase in mortality by almost fivefold. Community COVID-19 incidence (cases/105 people/week) was a statistically independent predictor of mortality. TRIAL REGISTRATION NUMBER: CEIM 20/217.

Intrachiasmatic craniopharyngioma: Assessment of visual outcome with optical coherence tomography after complete surgical removal.

BACKGROUND: Optic chiasm invasion by a craniopharyngioma (CP) is exceptional. Surgical treatment of intrachiasmatic CPs associates a high risk of chiasm injury, which should be properly addressed before surgery. CASE DESCRIPTION: We present a 46-year-old woman admitted to the hospital with low visual acuity (0.1 in the right eye and 0.5 in the left) and a severe defect in her visual fields, in addition to headaches, diabetes insipidus, and a long-term depressive disorder. Her visual deficit progressed from a right homonymous temporal inferior quadrantanopia to an almost complete loss of vision in both eyes that only spared the upper nasal quadrants. Brain MRI showed a rounded third ventricle tumor with a potbelly expansion of the optic chiasm, suggesting chiasm invasion by the tumor. Optical coherence tomography (OCT) showed the thinning of the retinal nerve fiber layer (RNFL) in the superior and temporal wedges of the right eye and in the temporal wedge of the left one. The tumor was completely removed by employing a frontotemporal craniotomy and a translamina terminalis approach. Histological analysis showed a squamous-papillary CP. Postoperatively, a significant worsening of the visual defect was evidenced on the perimetry, which was related to a marked RNFL atrophy measured with OCT, as compared to the preoperative study. The poor long-term visual outcome in this patient correlated well with the results of postoperative OCT. CONCLUSIONS: Preoperative analysis of retinal atrophy with optic coherence tomography allows a reliable assessment of the patient's visual outcome in CPs involving the optic chiasm.

Meningiomas Originated at the Falcotentorial Region: Analysis of Topographic and Diagnostic Features Guiding an Optimal Surgical Planning.

BACKGROUND: Meningiomas arising at the pineal region are a rare entity and still represent a great neurosurgical challenge given their deep location and critical neuroanatomic relationships. The optimal surgical approach to treat these lesions is still under debate. Our objective is to review the topographic and diagnostic features of these lesions, which can help to guide an optimal surgical outcome. METHODS: We present 2 clinical cases of falcotentorial meningiomas successfully treated at our institution (2016-2017) with different surgical approaches. A literature review is performed, and a description of the classification, anatomic relationships, clinical features, diagnosis, and different surgical options and outcomes of these lesions is presented. RESULTS: The first patient was treated via a supracerebellar infratentorial approach, and the second patient was treated via a parieto-occipital interhemispheric approach. In both tumors, a gross total resection was achieved with no permanent neurologic deficits. In the literature review, gross total resection rates range from 33% to 100%, with no differences regarding the type of meningioma or the surgical approach performed. Permanent neurologic morbidity varies from 0% to 50%, and mortality rates range from 0% to 23%. The distortion and displacement of the vein of Galen and straight sinus represent the most important feature in the decision of optimal surgical approach. CONCLUSIONS: Pineal region meningiomas represent very infrequent, challenging lesions, and their description in the literature is scarce. The systematic topographic classification of these tumors and evaluation of the neuroanatomic structures involved are crucial to guide a safe and optimal surgical approach and achieve satisfactory outcomes.

Subcutaneous tissue metastasis from glioblastoma multiforme: A case report and review of the literature. / Metástasis en tejido celular subcutáneo de glioblastoma multiforme: caso clínico y revisión de la literatura.

Glioblastoma multiforme is the most common primary brain tumor, despite an aggressive clinical course, less than 2% of patients develop extraneural metastasis. We present a 72-year-old male diagnosed with a right temporal glioblastoma due to headache. He underwent total gross resection surgery and after that the patient was treated with adyuvant therapy. Five months after the patient returned with trigeminal neuralgia, and MRI showed an infratemporal cranial mass which infiltrates masticator space, the surrounding bone, the temporal muscle and superior cervical and parotid lymph nodes. The patient underwent a new surgery reaching partial resection of the temporal lesion. After that the patient continued suffering from disabling trigeminal neuralgia, that's why because of the bad clinical situation and the treatment failure we decided to restrict therapeutic efforts. The patient died 3 weeks after the diagnosis of extracranial metastasis.

Morphometrical evaluation of decompression obtained through corpectomy. Heading towards to posterior approaches. / Evolución morfométrica de descompresión obtenida tras corpectomía. Dirigiéndonos hacia abordajes posteriores.

INTRODUCTION: We analysed the decompression obtained by dorsal or dorsolumbar corpectomy measured by Cobb angle and the spinal area prior to and after surgery and compared the evolution of the technique over the last five years of the study. MATERIAL AND METHOD: A retrospective review of patients operated between 2005 and 2015 through anterior or posterior approaches was performed. RESULTS: 24 patients were studied and a significant improvement was observed between the preoperative and postoperative morphometrical measurement (4.18° correction of the kyphosis and an increase of 130.8mm2 in the spinal canal, p<.001 in both cases) and in clinical parameters (45.8% of patients improved in ASIA, and Karnofsky showed 13 points of improvement, p<.001 in both cases). However, there was no correlation between clinical and morphological parameters. We also observed that in the last five years of the study posterior approaches were more frequently used with good results. CONCLUSIONS: Dorsal corpectomy allows significant spinal decompression, with neurological improvement but this does not correlate with the measurement of decompression. Thanks to technical improvements, less invasive techniques (posterior approaches and MISS) allow good clinical results, which are similar to those obtained by anterior techniques.

Validation of Grading Scores and Outcome Prognostic Factors in Intracranial Meningiomas in Elderly Patients.

OBJECTIVE: Meningiomas are the most frequent benign intracranial tumors and they are becoming more frequent because of the aging population and advances in diagnostics and neurosurgical treatment. Therefore, there will be an increase of this disease in the coming years. METHODS: We performed a retrospective analysis of patients older than 70 years who underwent surgery for intracranial meningiomas, and we established risk factors related to outcome, morbidity, and mortality. We compared 3 previously described scores (Geriatric Scoring System [GSS], Clinico-Radiological Grading System [CRGS], and Sex, Karnofsky, ASA, Location and Edema [SKALE] score). RESULTS: We identified 110 patients older than 70 years. In the univariate analysis, postoperative Karnofsky Performance Status (KPS) was related to the presence of edema (P = 0.036), tumor size (P = 0.043), previous neurologic impairment (P = 0.012), and preoperative American Society of Anesthesiologists (ASA) physical status classification (P = 0.029). In the multivariable logistic regression model, ASA classification (odds ratio, 0.324; P = 0.04) and preoperative KPS (odds ratio, 1.042; P = 0.05) were also statistically significant. In all cases, better survival curves in the Kaplan-Meier survival test appear in patients with lower scores (CRGS, P = 0.015; GSS, P = 0.014; SKALE, P < 0.001). Also, morbidity measured as postoperative KPS correlated with these scores (CRGS, P < 0.001; SKALE, P < 0.001; GSS, P < 0.001). However, only SKALE correlated with perioperative morbidity, mortality, and 1-year mortality. CONCLUSIONS: Meningioma resection in patients older than 70 years is safe, with an acceptable rate of mortality and morbidity. Patients who should undergo surgery must be selected in relation to their comorbidities, such as ASA classification or preoperative KPS. However, SKALE could be a useful tool as an initial approach.

Usefulness of Reintervention in Recurrent Glioblastoma: An Indispensable Weapon for Increasing Survival.

BACKGROUND: Glioblastoma is the most frequent primary brain tumor and despite of complete treatment survival is still poor. The aim of this study is to define the utility of reoperation for improving survival in patients with recurrent glioblastoma, and determine other prognostic factors associated with longer survival. METHODS: We performed a retrospective analysis of those patients who underwent surgery and compared those who were operated two or more times and those who received surgery only once. We studied overall survival (OS), progression-free survival (PFS), and clinical variables that could be related with higher survival. RESULTS: A total of 121 patients were eligible for the study, of whom 31 (25%) underwent reoperation. The reoperation group had a mean and median increase survival of 10.5 and 16.4 months in OS and 3.5 and 2.7 months for PFS compared with the non-reoperation group (P < 0.001 and 0.01, respectively). Although complications were higher in patients that underwent reintervention (19.3%) there was no statistical difference with complication rate in first surgery (12.4%, χ2 = 1.86; P = 0.40). Cox multivariable analysis revealed that age (hazard ratio [HR] 1.03; 95% confidence interval [CI], 1.006-1.055; P = 0.013), reoperation (HR, 0.48; 95% CI, 0.285-0.810; P = 0.006), extent of resection >95% (HR, 0.547; 95% CI, 0.401-0.748; P < 0.001), and complete adjuvant therapy (HR, 0.389; 95% CI, 0.208-0.726; P = 0.003) were correlated with a higher OS. CONCLUSIONS: Reoperation and the extent of resection (EOR) are the only surgical variables that neurosurgeons can modify to improve survival in our patients. Higher EOR and reoperation rates in patients who can be candidates for second surgery, will increase OS and PFS.