Lateral-type posterior fossa ependymomas in pediatric patients: a national collaborative study.

PURPOSE: To review a multicentric series of lateral-type posterior fossa ependymomas operated in the last ten years and to analyze the factors related to clinical evolution and tumor survival. METHODS: Descriptive, retrospective study. Active members of the Spanish Society of Pediatric Neurosurgery were invited to participate in this multicentric study. Clinical and radiological data were incorporated to an open database. The role of histologic grade, grade of resection, postoperative morbidities, and clinical follow-up was evaluated through bivariate associations (chi-square), Kaplan-Meier's curves (log-rank test), and multivariate analysis (binary logistic regression). RESULTS: Fourteen centers entered the study, and 25 cases with a minimum follow-up of 6 months were included. There were 13 boys and 12 girls with a mean age close to 3 years. Mean tumor volume at diagnosis was over 60 cc. A complete resection was achieved in 8 patients and a near-total resection in 5 cases. Fifteen tumors were diagnosed as ependymoma grade 2 and ten as ependymoma grade 3. Major morbidity occurred postoperatively in 14 patients but was resolved in twelve within 6 months. There were six cases of death and 11 cases of tumor progression along the observation period. Mean follow-up was 44.8 months. Major morbidity was significantly associated with histologic grade but not with the degree of resection. Overall and progression-free survival were significantly associated with complete surgical resection. At the last follow-up, 16 patients carried a normal life, and three displayed a mild restriction according to Lansky's scale. CONCLUSIONS: Lateral-type posterior fossa ependymomas constitute a specific pathologic and clinical tumor subtype with bad prognosis. Gross total resection is the goal of surgical treatment, for it significantly improves prognosis with no additional morbidity. Neurological deficits associated to lower cranial nerve dysfunction are common, but most are transient. Deeper genetic characterization of these tumors may identify risk factors that guide new treatments and stratification of adjuvant therapies.

Clinical improvement after cranioplasty and its relation to body position and cerebral hemodynamics.

Cranioplasty after decompressive craniectomy (DC) has been found to improve the neurological condition. The underlying mechanisms are still unknown. The aim of this study is to investigate the roles of the postural changes and atmospheric pressure (AP) in the brain hemodynamics and their relationship with clinical improvement. Seventy-eight patients were studied before and 72 h after cranioplasty with cervical and transcranial color Doppler ultrasound (TCCS) in the sitting and supine positions. Craniectomy size, shape, and force exerted by the AP (torque) were calculated. Neurological condition was assessed with the National Institutes of Health Stroke Scale (NIHSS) and the Barthel index. Twenty-eight patients improved after cranioplasty. Their time elapsed from the DC was shorter (214 vs 324 days), preoperative Barthel was worse (54 vs 77), internal carotid artery (ICA) mean velocity of the defect side was lower while sitting (14.4 vs 20.9 cm/s), and torque over the craniectomy was greater (2480.3 vs 1464.3 N*cm). Multivariate binary logistic regression showed the consistency of these changes. TCCS findings were no longer present postoperatively. Lower ICA (defect side) velocity in the sitting position correlates significantly with clinical improvement. Greater torque exerted by the AP might explain different susceptibilities to postural changes, corrected by cranioplasty.

Delayed extensive brain edema caused by the growth of a giant basilar apex aneurysm treated with basilar artery obliteration: a case report.

BACKGROUND: Partially thrombosed giant aneurysms at the basilar apex (BA) artery are challenging lesions with a poor prognosis if left untreated. Here we describe a rare case of extensive brain edema after growth of a surgically treated and thrombosed giant basilar apex aneurysm. CASE PRESENTATION: We performed a proximal surgical basilar artery occlusion on a 64-year-old female with a partially thrombosed giant BA aneurysm. MRI showed no ischemic lesions but showed marked edema adjacent to the aneurysm. She had a good recovery, but 3 months after surgical occlusion, her gait deteriorated together with urinary incontinence and worsening right hemiparesis. MRI showed that the aneurysm had grown and developed intramural hemorrhage, which caused extensive brain edema and obstructive hydrocephalus. She was treated by a ventriculoperitoneal shunt placement. Follow-up MRI showed progressive brain edema resolution, complete thrombosis of the lumen and shrinkage of the aneurysm. At 5 years follow-up the patient had an excellent functional outcome. CONCLUSIONS: Delayed growth of a surgically treated and thrombosed giant aneurysm from wall dissection demonstrates that discontinuity with the initial parent artery does not always prevent progressive enlargement. The development of transmural vascular connections between the intraluminal thrombus and adventitial neovascularization by the vasa vasorum on the apex of the BA seems to be a key event in delayed aneurysm growth. Extensive brain edema might translate an inflammatory edematous reaction to an abrupt enlargement of the aneurysm.

[Competency-based Neurosurgery Residency Programme]. / El nuevo programa de Residencia en Neurocirugía basado en competencias.

A programme proposal for competency-based Neurosurgery training adapted to the specialization project is presented. This proposal has been developed by a group of neurosurgeons commissioned by the SENEC (Spanish Society of Neurosurgery) and could be modified to generate a final version that could come into force coinciding with the implementation of the specialization programme. This document aims to facilitate the test of the new programme included in the online version of our journal. DURATION OF THE PROGRAMME: Total training period is 6 years; initial 2 years belong to the surgery specialization and remaining 4 years belong to core specialty period. STRUCTURE OF THE PROGRAMME: It is a competency-based programmed based on the map used by the US Accreditation Council for Graduate Medical Education (ACGME) including the following domains of clinical competency: Medical knowledge, patient care, communication skills, professionalism, practice-based learning and improvement, health systems, interprofessional collaboration and professional and personal development. Subcompetencies map in the domains of Knowledge and Patient care (including surgical competencies) was adapted to the one proposed by AANS and CNS (annex 1 of the programme). A subcompetency map was also used for the specialization rotations. INSTRUCTION METHODS: Resident's training is based on personal study (self-learning) supported by efficient use of information sources and supervised clinical practice, including bioethical instruction, clinical management, research and learning techniques. EVALUATION METHODS: Resident evaluation proposal includes, among other instruments, theoretical knowledge tests, objective and structured evaluation of the level of clinical competency with real or standardised patients, global competency scales, 360-degree evaluation, clinical record audits, milestones for residents progress and self-assessment (annex 2). Besides, residents periodically assess the teaching commitment of the department's neurosurgeons and other professors participating in rotations, and annually assess the overall operation of the programme. Results of evaluations are registered, together with other relevant data, in the Resident's Book. PROGRAMME'S NATIONAL COMMITTEE: The creation of a Programme Committee directly attached to the SENEC (National Commission) that, aside from generating a final version of the programme, monitors its implementation (level of adherence and operation in the different departments), assumes the creation of test banks and the centralized administration of knowledge tests (in the middle of the residency and/or at the end of it) and centralizes information collected by tutors that could be used for re-accreditation of the services, is proposed.

[Variability in the management of aneurysmal subarachnoid haemorrhage in Spain: Analysis of the prospective multicenter database from the Working Group on Neurovascular Diseases of the Spanish Society of Neurosurgery]. / Variabilidad en el manejo de la hemorragia subaracnoidea aneurismática en España: análisis de la base de datos multicéntrica del Grupo de Trabajo de Patología Vascular de la Sociedad Española de Neurocirugía.

INTRODUCTION: In aneurysmal subarachnoid haemorrhage, endovascular or surgical exclusion of the aneurysm responsible for the bleeding is mandatory to prevent re-bleeding. In Spain there is no data regarding the frequency of usage of the two techniques, the moment treatment is performed, the existence of variability among the different centres treating these patients or the factors that determine the election of the therapeutic modality. OBJECTIVES: 1) To describe the variability in the use of endovascular treatment or surgery in the treatment of these patients among the participating centres. 2) To establish which factors are related to the election of treatment and outcome. MATERIALS AND METHODS: Of all the patients included in the database, we selected 2,150 cases suffering confirmed aneurysmal subarachnoid haemorrhage from 10 centres that included patients regularly during the period between 2004 and 2012 with a data completeness index over 95%. A descriptive analysis on mode of aneurysm treatment was performed. A multivariate analysis of the factors related to treatment modality of the aneurysm and outcome was performed using logistic regression. RESULTS: The ratio endovascular/surgical treatment was 1.32. There was high variability among centres regarding the frequency of endovascular treatment (32-80%). No treatment was given to 17% of the aneurysms, with this percentage being higher in the centres with lower rates of endovascular treatment. Lower volume centres treated aneurysms later. Age and poor clinical grade were factors related to the election of endovascular treatment, while middle cerebral artery location and unfavourable morphological criteria were factors of surgical treatment. The choice of treatment, guideline adherence and centre patient volume were not related to outcome. CONCLUSIONS: There is high variability in the election of treatment modality among centres in Spain. Endovascular treatment allows more patients to have their aneurysm treated. Guideline adherence is moderate.

Cranioplasty after decompressive craniectomy. A prospective series analyzing complications and clinical improvement.

BACKGROUND: Cranioplasty is carried out for cosmetic reasons and for protection, but it may also lead to some neurological improvement after the bone flap placement. Complications of cranioplasty are more frequent than expected for a scheduled neurosurgical procedure. We tried to identify factors associated with both complications and improvement after cranioplasty. METHODS: We prospectively studied the cranioplasties performed in our hospital from November 2009 to November 2013. Patients whose initial reason for bone removal was tumor infiltration were excluded. Demographic, clinical and radiological data were collected. The NIH Stroke Scale and Barthel Self-Care Index scores were obtained both before and within 72 h after cranioplasty. The outcome measures were the occurrences of complications and clinical improvement. RESULTS: Fifty-five cranioplasties were performed. The material used for the cranioplasty was autologous bone in 42 cases, polyetheretherketone (PEEK) in 7 and methacrylate in 6. The average size of the bone defect was 69.5 (19.5-149.5) cm2. The time elapsed between decompressive craniectomy and cranioplasty was 309 (25-1217) days. There were 10 complications (7 severe and 3 mild), an 18.2% complication rate. Statistically significant risk factors of complications were identified as a Barthel≤70 (Odds ratio [OR] 22; 2.5-192; P=0.005), age over 45 years (OR 13.5; 1.5-115; P=0.01) and early surgery (≤85 days; OR 8; 1.69-37.03, P=0.004). After multivariate analysis, Barthel≤70 and age over 45 years remained independent predictors of complications. Twenty-two (40%) of the 55 patients showed objective improvement. Early surgery (<85 days) increased the likelihood of improvement (OR 4.67; 1.05-20.83; P=0.035). Larger bone defects seemed to be related with improvement, but differences in defect size were not statistically significant (75.3 vs 65.6 cm2; P=0.1). CONCLUSIONS: The complication rate of cranioplasty is higher than for other elective neurosurgical procedures. Older age, poorer functional situation (worse Barthel index score) and early surgery (≤85 days) are independent risk factors for complications. However, cranioplasty produces clinical benefits beyond protection and esthetic improvement. Earlier surgery and larger bone defects seem to increase the likelihood of clinical improvement.

[Selection of medical graduates for residency posts. A comparative study of the methodologies used in different countries]. / La selección de los graduados en Medicina para los puestos de residencia. Estudio comparativo de los métodos usados en diferentes países.

INTRODUCTION: The design of an appropriate method for the selection of medical graduates for residency posts is extremely important, not only for the efficiency of the method itself (accurate identification of most competent candidates), but also for its influence on the study and teaching methodologies operating in medical schools. Currently, there is a great variation in the criteria used in different countries and there is no definitively appropriate method. The use of isolated or combined criteria, such as the marks obtained by students in medical schools, their performance in tests of theoretical knowledge and evaluations of clinical competence, or personal interviews, have a limited value for identifying those candidates who will perform better during the residency and later on during independent practice. OBJECTIVES: To analyse the variability in the methodologies used for the selection of residents employed in different countries, in particular those used in the United Kingdom and USA, where external agencies and medical schools make systematic analyses of curriculum development. The advantages and disadvantages of national or transnational licensing examinations on the process of convergence and harmonization of medical degrees and residency programmes through Europe are discussed. The present analysis is used to design a new and more efficient multi-criteria methodology for resident selection in Spain, which will be published in the next issue of this journal. CONCLUSIONS: Since the multi-criteria methods used in UK and USA appear to be most consistent, these have been employed for designing the new methodology that could be applied in Spain. Although many experts in medical education reject national examinations for awarding medical degrees or ranking candidates for residency posts, it seems that, when appropriately designed, they can be used to verify the level of competence of graduating students without necessarily distorting curriculum implementation or improvement.

[The method of selection of the residents in Spain. Analysis of the examination MIR and offer of a new methodology]. / El método de selección de los residentes en España. Análisis del examen MIR y propuesta de una nueva metodología.

INTRODUCTION: The method for selecting medical graduates for residency positions has a strong influence on teaching and learning strategies in medical schools. The methodology currently used in Spain does not seem appropriate for ranking the candidates or improving curriculum development. Thus, and taking into account the most consistent methodologies used in the United Kingdom and USA, we have designed a new method to be used in our country. OBJECTIVES: To analyze the limitations of the methodology used in Spain, and propose a new one aimed to improve the accuracy of selection itself and avoiding the negative influence of the current method on curricular development. In addition, we emphasize the necessity of improving teaching and learning in the clinical context to assure that graduating students reach an adequate level of clinical competence. CONCLUSIONS: The method for selecting candidates to residency post currently used in Spain, which relies mainly on testing theoretical knowledge, should be changed for an alternative methodology taking into account student,s performance through the course and assessing his/her ability for clínical contextualization of knowledge and level of clinical competence.

[Intracranial dural arteriovenous fistulae. Experience after 81 cases and literature review]. / Fístulas durales arteriovenosas intracraneales. Experiencia con 81 casos y revisión de la literatura.

OBJECTIVES: To analyse the clinical, radiological and therapeutic variables of intracranial dural arteriovenous fistulae (DAVF) treated at our institution, and to assess the validity of the Borden and Cognard classifications and their correlation with the presenting symptoms. MATERIAL AND METHODS: The DAVF identified were retrospectively analysed. They were classified according to their location, drainage pattern and the Borden and Cognard classifications. We recorded the different treatments, their complications and efficacy. RESULTS: There were 81DAVF identified between 1975 and 2012. The cavernous sinus (CS) location was the most frequent one. The Borden and Cognard classifications showed an interobserver Kappa index of 0.72 and 0.76 respectively. The odds ratio of aggressive presentation in the presence of cortical venous drainage (CVD) was 19.3 (2.8-132.4). No location, once adjusted by venous drainage pattern, showed significant association with an aggressive presentation. Endovascular transarterial treatment of cavernous sinus DAVF achieved symptomatic improvement of 78%, with a complication rate of 5%. The DAVF of non-CS locations, with CVD, treated surgically were angiographically shown cured in 100% of the cases, with no treatment-related complications. CONCLUSIONS: The presence of CVD was significantly associated with aggressive presentations. The Borden and Cognard classifications showed little interobserver variability. Endovascular treatment for CS DAVF is safe and relatively effective. Surgical treatment of non-CS DAVF with CVD is safe, effective and the first choice treatment in our environment.

Tumefactive multiple sclerosis requiring emergency craniotomy: case report and literature review.

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, characterized by focal neurological dysfunction with a relapsing and remitting course. Tumor-like presentation of MS (or "tumefactive"/"pseudotumoral" presentation) has been described before with a certain frequency; it consists of a large single plaque (>2cm) with presence of edema and mass effect and it is hard to distinguish from a brain tumor. However, we present a very rare case of a 53-year-old woman with a right temporal mass that turned out to be a MS plaque, who deteriorated within hours (brain herniation with loss of consciousness and unilateral mydriasis) and required an emergency craniotomy. We also present a review of the literature. It appears that only 4 cases of emergency craniotomy/craniectomy required in a patient with a tumor-like MS plaque have been reported before.

Multicentric and collaborative study of Spanish neurosurgical management of pediatric craniopharyngiomas: S-PedCPG.co.

PURPOSE: To present a descriptive analysis of pediatric craniopharyngiomas (PedCPG) treated in various Spanish hospitals, defining factors related to recurrence and performing a critical analysis of the results. METHODS: We undertook a multicenter retrospective review of PedCPG treated between 2000 and 2017. Data collected included epidemiological variables, clinical and radiological characteristics, goal of first surgery, rate of recurrence and its approach, adjuvant treatment, complications and permanent morbidity. Associations were studied between progression and number of progressions and independent variables. RESULTS: The study involved 69 children from 8 Spanish hospitals. Most of the tumors invaded several intracranial compartments at diagnosis, with the hypothalamus involved in 41.3% of cases. The first treatment strategy was usually gross total resection (GTR) (71%), with some patients treated with radiotherapy or intracystic chemotherapy. The progression rate after first surgery was 53% in a mean follow-up of 88.2 months (range 7-357). In the GTR group 38.8% of tumors recurred, 40% in the group of subtotal resection or biopsy and 93.3% in the cyst fenestration±Ommaya reservoir group. Mortality was 7.2%. Follow-up period, size of the tumor and goal of first surgery were significantly related with progression. CONCLUSIONS: Our results in terms of disease control, hormonal or visual impairment and mortality were acceptable, but there are several areas for improvement. Our short-term goals should be to create a national register of PedCPG, reach a consensus about a treatment algorithm, and improve diagnosis of hypothalamic dysfunction to avoid preventable morbidity.

Surgery for acute subdural hematoma: the value of pre-emptive decompressive craniectomy by propensity score analysis.

BACKGROUND: Acute subdural hematomas (ASDH) are found frequently following traumatic brain injury (TBI) and they are considered the most lethal type of mass lesions. The decision to perform a procedure to evacuate ASDH and the approach, either via craniotomy or decompressive craniectomy (DC), remains controversial. METHODS: We reviewed a prospectively collected series of 343 moderate to severe TBI patients in whom ASDH was the main lesion (ASDH volumes ≥10 cc). Patients with early comfort measures (early mortality prediction >50% and not ICP monitored), bilateral ASDH or the presence of another intracranial hematoma with volumes exceeding two times the volume of the ASDH were excluded. Among them, 112 were managed conservatively, 65 underwent ASDH evacuation by craniotomy and 166 by DC (103 pre-emptive DC, 63 obligatory DC). We calculated the average treatment effect by propensity score (PS) analysis using the following covariates: age, year, hypoxia, shock, pupils, major extracranial injury, motor score, midline shift, ASDH volume, swelling, intraventricular and subarachnoid hemorrhage presence. Then, multivariable binary regression and ordinal logistic regression analysis were performed to estimate associations between predictors and mortality and 12 months-GOS respectively. The patients' inverse probability weights were included as an independent variable in both regression models. RESULTS: The main variables associated with outcome were year, age, falls from patient´s own height, hypoxia, early deterioration, pupillary abnormalities, basal cistern effacement, compliance to ICP monitoring guidelines and type of surgical approach (craniotomy and pre-emptive DC). CONCLUSIONS: According to sliding dichotomy analysis, we found that patients in the intermediate or worst bands of unfavorable outcome prognosis seemed to achieve better than expected outcome if they underwent pre-emptive DC rather than craniotomy.

Pathogenesis of spinal intramedullary lipomas: two case reports.

BACKGROUND: Spinal lipomas not associated with dysraphism are rare and have an unknown natural history. In this report, we describe two cases; they showed recurrence during long-term follow-up, which makes us doubt a benign malformative etiology. CASE REPORTS: Two patients, a 19-year-old South American woman and a 14-year-old boy with spinal lipomas, underwent surgical resection. The lipomas were not associated with dysraphism and were located in the cervicothoracic and craniocervical junctions. In both cases, we decided to operate due to clinical progression; the former had a progressive natural course, and the latter experienced clinical worsening after recurrence from previous surgeries. The surgery took place with the assistance of neurophysiological monitoring and intraoperative ultrasound; a partial resection and medullary decompression were done, following the more recent recommendations. DISCUSSION: The natural history of these lesions is currently unknown due to their rarity and the heterogeneity in the long-term follow-up of previously reported cases. Although previous reports describe good outcomes after surgical resection, long follow-ups, especially in young subjects, may show differences in these outcomes with progression and recurrence. We contribute to this last piece of evidence by describing two more cases of progression and recurrence. LESSONS: Long-term close follow-up should be done in young subjects with spinal lipomas, as they are more prone to an aggressive course. Metabolism and hormonal changes may be behind this progression. Reoperation must be considered if neurological decline is detected.

Serum assessment of traumatic axonal injury: the correlation of GFAP, t-Tau, UCH-L1, and NfL levels with diffusion tensor imaging metrics and its prognosis utility.

OBJECTIVE: Diagnosis of traumatic axonal injury (TAI) is challenging because of its underestimation by conventional MRI and the technical requirements associated with the processing of diffusion tensor imaging (DTI). Serum biomarkers seem to be able to identify patients with abnormal CT scanning findings, but their potential role to assess TAI has seldomly been explored. METHODS: Patients with all severities of traumatic brain injury (TBI) were prospectively included in this study between 2016 and 2021. They underwent blood extraction within 24 hours after injury and imaging assessment, including DTI. Serum concentrations of glial fibrillary acidic protein, total microtubule-associated protein (t-Tau), ubiquitin C-terminal hydrolase L1 (UCH-L1), and neurofilament light chain (NfL) were measured using an ultrasensitive Simoa multiplex assay panel, a digital form of enzyme-linked immunosorbent assay. The Glasgow Outcome Scale-Extended score was determined at 6 months after TBI. The relationships between biomarker concentrations, volumetric analysis of corpus callosum (CC) lesions, and fractional anisotropy (FA) were analyzed by nonparametric tests. The prognostic utility of the biomarker was determined by calculating the C-statistic and an ordinal regression analysis. RESULTS: A total of 87 patients were included. Concentrations of all biomarkers were significantly higher for patients compared with controls. Although the concentration of the biomarkers was affected by the presence of mass lesions, FA of the CC was an independent factor influencing levels of UCH-L1 and NfL, which positioned these two biomarkers as better surrogates of TAI. Biomarkers also performed well in determining patients who would have had unfavorable outcome. NfL and the FA of the CC are independent complementary factors related to outcome. CONCLUSIONS: UCH-L1 and NfL seem to be the biomarkers more specific to detect TAI. The concentration of NfL combined with the FA of the CC might help predict long-term outcome.

Primary melanoma of the cauda equina: Case report and review of the literature.

The authors report the case of an 82 year-old woman with a primary malignant melanoma of the cauda equina resembling lumbar schwannoma in the MRI study. Melanocytic neoplasms are very rare but they should be included in the differential diagnosis of lesions involving the spinal nerves. The treatment of choice for these lesions is complete resection followed by radiotherapy. The outcomes reported in the literature are variable and are associated with the age of presentation, histopathological findings, extent of surgical resection and absence of metastatic lesions.

Hemodynamic alterations following a cerebellar arteriovenous malformation resection: Case report and densitometric quantitative analysis from CT imaging.

BACKGROUND: Cerebellar arteriovenous malformations (cAVMs) are rare and challenging lesions with an aggressive natural history. The mechanisms whereby a patient can worsen clinically after a supratentorial AVM resection include an acute alteration in cerebral hemodynamics, which is a known cause of postoperative hyperemia, edema and/or hemorrhage. These phenomena has not been described for cAVMS. Moreover, the underlying pathophysiology of edema and hemorrhage after AVM resection still remains controversial. METHODS: We report a patient that presented an abrupt neurological deterioration after cAVM surgical resection. Emergent external ventricular drainage to treat incipient hydrocephalus only partially reverted the patient's deterioration. Consecutive post-surgery CT images revealed fourth ventricle compression secondary to cerebellar swelling that concurred with a new neurological deterioration. Densitometric analysis was performed in these CT images to reveal the nature of these changes as well as their evolution over time. RESULTS: Importantly, we demonstrated a dynamic increase in the cerebellum mean density at the interval of Hounsfield values which correspond to hyperemia values. These changes were dynamic, and when hyperemia resolved and cerebellar density returned to basal levels, the fourth ventricle re-expanded and the patient neurologically recovered. CONCLUSIONS: This study demonstrated the utility of quantitative CT image analysis in the context of hemodynamic alterations following cAVM resection. Densitometric CT analysis demonstrated that hyperemic changes, but not ischemic ones, were time-dependent and were responsible for swelling and hemorrhage that conditioned neurological status and patient's evolution.

Traumatic axonal injury: is the prognostic information produced by conventional MRI and DTI complementary or supplementary?

OBJECTIVE: A traumatic axonal injury (TAI) diagnosis has traditionally been based on conventional MRI, especially on those sequences with a higher sensitivity to edema and blood degradation products. A more recent technique, diffusion tensor imaging (DTI), can infer the microstructure of white matter (WM) due to the restricted diffusion of water in organized tissues. However, there is little information regarding the correlation of the findings obtained by both methods and their use for outcome prognosis. The main objectives of this study were threefold: 1) study the correlation between DTI metrics and conventional MRI findings; 2) evaluate whether the prognostic information provided by the two techniques is supplementary or complementary; and 3) determine the incremental value of the addition of these variables compared to a traditional prognostic model. METHODS: The authors studied 185 patients with moderate to severe traumatic brain injury (TBI) who underwent MRI with DTI study during the subacute stage. The number and volume of lesions in hemispheric subcortical WM, corpus callosum (CC), basal ganglia, thalamus, and brainstem in at least four conventional MRI sequences (T1-weighted, T2-weighted, FLAIR, T2* gradient recalled echo, susceptibility-weighted imaging, and diffusion-weighted imaging) were determined. Fractional anisotropy (FA) was measured in 28 WM bundles using the region of interest method. Nonparametric tests were used to evaluate the colocalization of macroscopic lesions and FA. A multivariate logistic regression analysis was performed to assess the independent prognostic value of each neuroimaging modality after adjustment for relevant clinical covariates, and the internal validation of the model was evaluated in a contemporary cohort of 92 patients. RESULTS: Differences in the lesion load between patients according to their severity and outcome were found. Colocalization of macroscopic nonhemorrhagic TAI lesions (not microbleeds) and lower FA was limited to the internal and external capsule, corona radiata, inferior frontooccipital fasciculus, CC, and brainstem. However, a significant association between the FA value and the identification of macroscopic lesions in distant brain regions was also detected. Specifically, lower values of FA of some hemispheric WM bundles and the splenium of the CC were related to a higher number and volume of hyperintensities in the brainstem. The regression analysis revealed that age, motor score, hypoxia, FA of the genu of the CC, characterization of TAI lesions in the CC, and the presence of thalamic/basal ganglia lesions were independent prognostic factors. The performance of the proposed model was higher than that of the IMPACT (International Mission on Prognosis and Analysis of Clinical Trials in TBI) model in the validation cohort. CONCLUSIONS: Very limited colocalization of hyperintensities (none for microbleeds) with FA values was discovered. DTI and conventional MRI provide complementary prognostic information, and their combination can improve the performance of traditional prognostic models.

Intracranial Pressure Monitoring in Patients With Severe Traumatic Brain Injury: Extension of the Recommendations and the Effect on Outcome by Propensity Score Matching.

BACKGROUND: Intracranial pressure (ICP) monitoring is recommended for patients with traumatic brain injury (TBI) with a Glasgow Coma Scale (GCS) <9 on admission and revealing space-occupying lesions or swelling on computed tomography. However, previous studies that have evaluated its effect on outcome have shown conflicting results. OBJECTIVE: To study the effect of ICP monitoring on outcome after adjustment of patient's characteristics imbalance and determine the potential benefit on patients with higher GCS that deteriorates early or in the absence of computed tomography results suggesting high ICP. METHODS: We searched for adult patients with TBI admitted between 1996 and 2020 with a GCS <9 on admission or deterioration from higher scores within 24 hours after TBI. Patients were divided into groups if they fulfilled strict (Brain Trauma Foundation guidelines) or extended criteria (patients who worsened after admission or without space-occupying lesions) for ICP monitoring. Propensity score analyses based on nearest neighbor matching was performed. RESULTS: After matching, we analyzed data from 454 patients and 184 patients who fulfilled strict criteria or extended criteria for ICP monitoring, respectively. A decreased on in-hospital mortality was detected in monitored patients following strict and extended criteria . Those patients with a higher baseline risk of poor outcome showed higher odds of favorable outcome if they were monitored. CONCLUSION: ICP monitoring in patients with severe TBI within 24 hours after injury following strict and extended criteria was associated with a decreased in-hospital mortality. The identification of patients with a higher risk of an unfavorable outcome might be useful to better select cases that would benefit more from ICP monitoring.

The influence of aneurysm morphology on the volume of hemorrhage after rupture.

OBJECTIVE: Factors determining the risk of rupture of intracranial aneurysms have been extensively studied; however, little attention is paid to variables influencing the volume of bleeding after rupture. In this study the authors aimed to evaluate the impact of aneurysm morphological variables on the amount of hemorrhage. METHODS: This was a retrospective cohort analysis of a prospectively collected data set of 116 patients presenting at a single center with subarachnoid hemorrhage due to aneurysmal rupture. A volumetric assessment of the total hemorrhage volume was performed from the initial noncontrast CT. Aneurysms were segmented and reproduced from the initial CT angiography study, and morphology indexes were calculated with a computer-assisted approach. Clinical and demographic characteristics of the patients were included in the study. Factors influencing the volume of hemorrhage were explored with univariate correlations, multiple linear regression analysis, and graphical probabilistic modeling. RESULTS: The univariate analysis demonstrated that several of the morphological variables but only the patient's age from the clinical-demographic variables correlated (p < 0.05) with the volume of bleeding. Nine morphological variables correlated positively (absolute height, perpendicular height, maximum width, sac surface area, sac volume, size ratio, bottleneck factor, neck-to-vessel ratio, and width-to-vessel ratio) and two correlated negatively (parent vessel average diameter and the aneurysm angle). After multivariate analysis, only the aneurysm size ratio (p < 0.001) and the patient's age (p = 0.023) remained statistically significant. The graphical probabilistic model confirmed the size ratio and the patient's age as the variables most related to the total hemorrhage volume. CONCLUSIONS: A greater aneurysm size ratio and an older patient age are likely to entail a greater volume of bleeding after subarachnoid hemorrhage.

Hemodynamic alterations following a cerebellar arteriovenous malformation resection: Case report and densitometric quantitative analysis from CT imaging.

BACKGROUND: Cerebellar arteriovenous malformations (cAVMs) are rare and challenging lesions with an aggressive natural history. The mechanisms whereby a patient can worsen clinically after a supratentorial AVM resection include an acute alteration in cerebral hemodynamics, which is a known cause of postoperative hyperemia, edema and/or hemorrhage. These phenomena has not been described for cAVMS. Moreover, the underlying pathophysiology of edema and hemorrhage after AVM resection still remains controversial. METHODS: We report a patient that presented an abrupt neurological deterioration after cAVM surgical resection. Emergent external ventricular drainage to treat incipient hydrocephalus only partially reverted the patient's deterioration. Consecutive post-surgery CT images revealed fourth ventricle compression secondary to cerebellar swelling that concurred with a new neurological deterioration. Densitometric analysis was performed in these CT images to reveal the nature of these changes as well as their evolution over time. RESULTS: Importantly, we demonstrated a dynamic increase in the cerebellum mean density at the interval of Hounsfield values which correspond to hyperemia values. These changes were dynamic, and when hyperemia resolved and cerebellar density returned to basal levels, the fourth ventricle re-expanded and the patient neurologically recovered. CONCLUSIONS: This study demonstrated the utility of quantitative CT image analysis in the context of hemodynamic alterations following cAVM resection. Densitometric CT analysis demonstrated that hyperemic changes, but not ischemic ones, were time-dependent and were responsible for swelling and hemorrhage that conditioned neurological status and patient's evolution.