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.

A prospective study to identify preoperative serum parameters for spinal implant infection detected by sonication fluid culture.

PURPOSE: Low-virulent microorganisms identified on pedicle screws by sonication fluid culture (SFC) are an important cause of implant loosening. While sonication of explanted material improves the detection rate, the risk of contamination exists and no standardized diagnostic criteria for chronic low-grade spinal implant-related infection (CLGSII) are stablished. Besides, the role of serum C-reactive protein (CRP) and procalcitonin (PCT) in CLGSII has not been adequately investigated. METHODS: Blood samples were collected prior to implant removal. To increase sensitivity, the explanted screws were sonicated and processed separately. Patients exhibiting at least one positive SFC were classified in the infection group (loose criteria). To increase specificity, the strict criteria only considered multiple positive SFC (≥ 3 implants and/or ≥ 50% of explanted devices) as meaningful for CLGSII. Factors which might promote implant infection were also recorded. RESULTS: Thirty-six patients and 200 screws were included. Among them, 18 (50%) patients had any positive SFCs (loose criteria), whereas 11 (31%) patients fulfilled the strict criteria for CLGSII. Higher serum protein level was the most accurate marker for the preoperative detection of CLGSSI, exhibiting an area under the curve of 0.702 (loose criteria) and 0.819 (strict criteria) for the diagnosis of CLGSII. CRP only exhibited a modest accuracy, whereas PCT was not a reliable biomarker. Patient history (spinal trauma, ICU hospitalization and/or previous wound-related complications) increased the likelihood of CLGSII. CONCLUSION: Markers of systemic inflammation (serum protein level) and patient history should be employed to stratify preoperative risk of CLGSII and decide the best treatment strategy.

Atlanto-occipital dislocation with concomitant severe traumatic brain injury: A retrospective study at a level 1 trauma center / Luxación atlantooccipital con traumatismo craneoencefálico grave concomitante: estudio retrospectivo en un centro de trauma de nivel 1

Background: Traumatic atlanto-occipital dislocation (AOD) is a life-threatening injury. Although traumatic brain injury (TBI) is associated with increased mortality in AOD patients, a detailed individual analysis of these patients is lacking in the literature. Methods: Patients ≥16 years old who were diagnosed of AOD with concomitant severe TBI from 2010 to 2020 were included in this retrospective study. We examined the epidemiology, injury mechanisms, associated injuries, and outcomes of these patients. Results: Eight patients were included. Six patients died before any intervention could be performed, and two patients underwent an occipito-cervical fixation, showing a notorious neurologic improvement on follow-up. Cardiorespiratory arrest (CRA) was a strong predictor of subsequent death. CT signs of diffuse axonal injury (DAI) were present in most patients and were confirmed by magnetic resonance imaging (MRI) in survivors. Although TBI was not the main cause of death, it was responsible for the delayed neurological improvement and deferred stabilization. The average sensitivity of the different used methodologies for AOD diagnosis ranged from 0.50 to 1.00, being the Basion Dens Interval (BDI) and the Condyle-C1 interval (CCI) sum the most reliable criteria. Non-survivors tended to show greater distraction measurements. The high incidence of condylar avulsion fractures suggests that their visualization on the initial CT study should heighten the suspicion for AOD. Conclusions: Our data suggest that patients with AOD and concomitant severe TBI might be salvageable patients. In those who survive beyond the first hospital days and show neurological improvement, surgical treatment should be performed as they can achieve an important neurologic recovery. (AU)

Antecedentes: La luxación atlantooccipital (AOD) traumática es una lesión potencialmente mortal. Aunque el traumatismo craneoencefálico (TCE) se asocia con un aumento de la mortalidad en los pacientes con AOD, no existe en la literatura un análisis individual detallado de estos pacientes. Métodos: En este estudio retrospectivo se incluyeron pacientes mayores de 16 años que fueron diagnosticados de AOD con TCE grave concomitante durante el periodo 2010-2020. Estudiamos la epidemiología, los mecanismos lesionales, así como las lesiones asociadas y los resultados de estos pacientes. Resultados: Se incluyeron ocho pacientes. Seis pacientes fallecieron antes de que se pudiera realizar cualquier intervención y dos pacientes fueron sometidos a una fijación occipitocervical, mostrando una notoria mejoría neurológica durante el seguimiento. La parada cardiorrespiratoria fue un predictor de muerte. En la TC inicial, signos de lesión axonal difusa estaban presentes en la mayoría de los pacientes y se confirmaron mediante imágenes de resonancia magnética en los supervivientes. Aunque el TCE no fue la principal causa de muerte, fue responsable de una mejoría neurológica tardía y por ello una estabilización diferida. La sensibilidad de las diferentes metodologías utilizadas para el diagnóstico de AOD osciló entre 0,50 y 1,00, siendo el intervalo Basion Dens y la suma del intervalo Condylo-C1 los criterios más fiables. Además, los no supervivientes presentaban mayores medidas de distracción. La alta incidencia de fracturas de cóndilo por avulsión sugiere que su visualización en el estudio de TC inicial debería aumentar la sospecha de AOD. Conclusiones: Nuestros datos sugieren que los pacientes con AOD y TCE grave concomitante podrían ser pacientes salvables. En aquellos que sobreviven más allá de los primeros días de...(AU)Palabras clave:Luxación atlantooccipitalColumna cervicalUnión craneocervicalFusión occipitocervicalTraumatismo craneoencefálico

Atlanto-occipital dislocation with concomitant severe traumatic brain injury: A retrospective study at a level 1 trauma center.

BACKGROUND: Traumatic atlanto-occipital dislocation (AOD) is a life-threatening injury. Although traumatic brain injury (TBI) is associated with increased mortality in AOD patients, a detailed individual analysis of these patients is lacking in the literature. METHODS: Patients ≥16 years old who were diagnosed of AOD with concomitant severe TBI from 2010 to 2020 were included in this retrospective study. We examined the epidemiology, injury mechanisms, associated injuries, and outcomes of these patients. RESULTS: Eight patients were included. Six patients died before any intervention could be performed, and two patients underwent an occipito-cervical fixation, showing a notorious neurologic improvement on follow-up. Cardiorespiratory arrest (CRA) was a strong predictor of subsequent death. CT signs of diffuse axonal injury (DAI) were present in most patients and were confirmed by magnetic resonance imaging (MRI) in survivors. Although TBI was not the main cause of death, it was responsible for the delayed neurological improvement and deferred stabilization. The average sensitivity of the different used methodologies for AOD diagnosis ranged from 0.50 to 1.00, being the Basion Dens Interval (BDI) and the Condyle-C1 interval (CCI) sum the most reliable criteria. Non-survivors tended to show greater distraction measurements. The high incidence of condylar avulsion fractures suggests that their visualization on the initial CT study should heighten the suspicion for AOD. CONCLUSIONS: Our data suggest that patients with AOD and concomitant severe TBI might be salvageable patients. In those who survive beyond the first hospital days and show neurological improvement, surgical treatment should be performed as they can achieve an important neurologic recovery.

Novel CT-based parameters assessing relative cross-sectional area to guide surgical management and predict clinical outcomes in patients with acute subdural hematoma.

INTRODUCTION: Acute subdural hematoma (aSDH) is one of the most devastating entities secondary to traumatic brain injury (TBI). Even though radiological computed tomography (CT) findings, such as hematoma thickness (HT), midline shift (MLS), and MLS/HT ratio, have an important prognostic role, they suffer from important drawbacks. We hypothesized that relative cross-sectional area (rCSA) of specific brain regions would provide valuable information about brain compression and swelling, thus being a key determining factor governing the clinical course. METHODS: We performed an 8-year retrospective analysis of patients with moderate to severe TBI with surgically evacuated, isolated, unilateral aSDH. We investigated the influence of aSDH rCSA and ipsilateral hemisphere rCSA along the supratentorial region on the subsequent operative technique employed for aSDH evacuation and patient's clinical outcomes (early death and Glasgow Outcome Scale [GOS] at discharge and after 1-year follow-up). Different conventional radiological variables were also assessed. RESULTS: The study included 39 patients. Lower HT, MLS, hematoma volume, and aSDH rCSA showed a significant association with decompressive craniectomy (DC) procedure. Conversely, higher ipsilateral hemisphere rCSA along the dorso-ventral axis and, specifically, ipsilateral hemisphere rCSA at the high convexity level were predictors for DC. CT segmentation analysis exhibited a modest relationship with early death, which was limited to the basal supratentorial subregion, but could not predict long-term outcome. CONCLUSION: rCSA is an objectifiable and reliable radiologic parameter available on admission CT that might provide valuable information to optimize surgical treatment.

Effects of cranioplasty in cerebral blood perfusion using quantification with 99m-Tc HMPAO SPECT-CT.

BACKGROUND AND PURPOSE: Syndrome of the trephined or sinking skin flap syndrome is an underdiagnosed condition of craniectomized patients that usually improves after cranioplasty. Among the pathophysiological theories proposed, the changes of cerebral blood perfusion (CBP) caused by cranial defects might have a role in the neurological deficiencies observed. We aim to assess the regional cortex changes in CBP after cranioplasty with Technetium 99m hexamethylpropylene-amine oxime (99mTc-HMPAO) SPECT-CT. METHODS: Twenty-eight craniectomized patients subject to cranioplasty were studied with 99mTc-HMPAO SPECT-CT in three different times, before cranioplasty, a week, and 3 months after. The images were processed with quantification software comparing CBP of 24 cortical areas with a reference area, and with a database of controls. A mixed effects model and T-Student were used. RESULTS: CBP increased significantly in both hemispheres after cranioplasty, either using ratio (ß = .019, p-value = .030 first postsurgical SPECT-CT and ß = .021, p-value = .015 in the second study, vs. presurgical) or Z-score (ß = .220, p-value = .026 and ß = .279, p-value = .005, respectively). Nine areas of the damaged side had a significant lower CBP ratio and Z-score than the undamaged. Posterior cingulate showed an increased CBP ratio (p-value = .034) and Z-score (p-value = .028) in the first postsurgical SPECT-CT. These posterior cingulate changes represent a 4.83% increase in ratio and 91.04% in Z-Score (p-value = .035 and .040, respectively). CONCLUSION: CBP changes significantly in specific cortical areas after cranioplasty. Posterior cingulate changes might explain some improvements in attention impairments. SPECT-CT could be a useful tool to assess CBP changes in these patients and might be helpful in their clinical management.

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.

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.

Efficacy of percutaneous pedicle screws for thoracic and lumbar spine fractures compared with open technique.

BACKGROUND: The objective of this study is to compare percutaneous techniques (MIS) with the open technique in terms of angle correction, long-term maintenance and clinical results. METHODS: The authors collected a prospective database of thoraco-lumbar fractures treated with posterior stabilization without fusion from 2013 to 2019. The statistical analysis has been carried out retrospectively. The patients were classified into Open and MIS group. To compare the two population, samples, treatments and mitigate the differences between the groups, the propensity score (PS) matching was used. RESULTS: One hundred and eight patients with thoraco-lumbar fractures were included. After performing the PS, 21 patients were obtained in the open group and 28 in the MIS group. For operative and perioperative parameters there were no differences in number of patients with posterior decompression, number of instrumented segments, number of total screws, operative time and complications. Postoperative hemoglobin was similar in both groups. However, in the open group a greater loss of hemoglobin was observed; as well as, higher analgesia requirements and length of stay. No statistically significant differences were observed in neurological status in both groups in the preoperative, postoperative period and at follow-up. The Cobb angle showed no differences at admission comparing both groups. A similar angle correction was observed with both surgeries, but in open surgery there was a statistically significant loss of correction. CONCLUSIONS: We observed in this study that the MIS technique for the treatment of thoracolumbar fractures is as effective as the open technique in terms of angle correction; and demonstrated that is better in its maintenance over time. Clinical results were at least as good as with the open technique.

A Frontal Route to Middle and Posterior Cranial Fossa: Quantitative Study for the Lateral Transorbital Endoscopic Approach and Comparison with the Subtemporal Approach.

BACKGROUND: Skull base lesions within the middle cranial fossa (MCF) remain challenging. Recent reports suggest that transorbital endoscopic approaches (TOEAs) might be particularly suitable to access the MCF and expose the lateral wall of the cavernous sinus and the Meckel's cave. METHODS: The present study was developed to compare the nuances of the subtemporal approach (STA) with those of the lateral TOEA (LTOEA) to the MCF and posterior cranial fossa (PCF) in cadaveric specimens. After orbital craniectomy, interdural opening of the cavernous sinus lateral wall (CSlw), exposure of the Gasserian ganglion, and extradural elevation of the temporal lobe was performed. Next, anterior endoscopic petrosectomy was performed and the PCF was accessed. We quantitatively analyzed and compared the angles of attack and distances between LTOEA and STA to different structures at the CSlw, petrous apex (PA), and PCF. RESULTS: Cadaveric dissection through the LTOEA completely exposed the CSlw and PA. LTOA exhibited larger distances than the STA to all targets. Importantly, these differences were greater at the PA and its surrounding key anatomic landmarks. The horizontal and vertical angles of attack allowed by the LTOA were smaller both for the CSlw and PA. However, these differences were not significant for the vertical angle of attack at the CSlw. CONCLUSIONS: LTOEA provides a direct ventral route to the medial aspect of MCF, PA, and PCF. Although TOEAs are versatile approaches, the unfamiliar surgical anatomy and limited instrument maneuverability demand extensive cadaveric dissection before moving to the clinical setting.

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.

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.

Racemose Fourth Ventricle Neurocysticercosis Excision Through Telovelar Approach and Hydrodissection.

Intraventricular neurocysticercosis is associated with more severe complications and a worse overall outcome.1,2 Fourth ventricle neurocysticercosis (FVNCC) often presents with cerebrospinal fluid obstruction and hydrocephalus by means of direct mechanical occlusion of ventricular outlets by the cysts or due to an ependymal inflammatory response. Unfortunately, there is little consensus on the optimal management for FVNCC. If possible, surgical removal of cysticerci rather than medical therapy and/or shunt surgery is recommended.3 Endoscopic removal of cysts is described to be an effective treatment modality.4 However, endoscopic removal of inflamed or adherent ventricular cysticerci is associated with increased risk of complications.5 Although microdissection through a posterior fossa telovelar approach is a valid method for FVNCC,6,7 scarce reports describe the therapeutic decision making and provide a surgical video of adherent FVNCC cyst resection. Video 1 shows a 40-year-old female born in Honduras who presented with progressive headache. Computed tomography revealed ventriculomegaly and transependymal flow. Magnetic resonance imaging demonstrated obstructive hydrocephalus secondary to a multiloculated cystic mass within the fourth ventricle. According to the diagnostic criteria, probable racemose FVNCC was suspected.8 Magnetic resonance imaging raised suspicion that the cysts could be densely adherent to surrounding structures,9 precluding endoscopic removal. We performed a combined microscopic and endoscopic approach, which permitted removal of the cysts through a telovelar approach and hydrodissection technique without damaging nearby structures and treatment of the associated hydrocephalus through an endoscopic third ventriculostomy, allowing complete resolution of symptoms and avoidance of cerebrospinal fluid shunting.

Hemodynamic alterations following a cerebellar arteriovenous malformation resection: Case report and densitometric quantitative analysis from CT imaging / Alteraciones hemodinámicas tras la resección de una malformación arteriovenosa cerebelosa: caso clínico y análisis cuantitativo densitométrico de las imágenes de tomografía computarizada cerebral

BackgroundCerebellar 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.MethodsWe 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.ResultsImportantly, 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.ConclusionsThis 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 (AU)

AntecedentesLas malformaciones arteriovenosas cerebelosas (MAVc) son lesiones raras, con una historia natural agresiva. Los mecanismos por los que un paciente puede empeorar clínicamente después de la resección de una MAV supratentorial incluyen una alteración aguda en la hemodinámica cerebral, que es una causa conocida de hiperemia, edema y/o hemorragia postoperatorios. Sin embargo, estos fenómenos no se han descrito en las MAVc. Además, la fisiopatología subyacente de este edema y la hemorragia tras la resección de una MAV sigue siendo controvertida.MétodosExponemos el caso de una paciente que presentó un deterioro neurológico abrupto después de la resección quirúrgica de una MAVc. El drenaje ventricular externo para tratar la hidrocefalia solo revirtió parcialmente el deterioro de la paciente. Las imágenes secuenciales de la tomografía computarizada (TC) posquirúrgicas revelaron compresión del cuarto ventrículo secundaria a edema cerebeloso, que fue concomitante con un nuevo deterioro neurológico. En las imágenes de la TC se realizó un análisis densitométrico para revelar la naturaleza de estos cambios, así como su evolución en el tiempo.ResultadosNuestro análisis demostró un aumento en la densidad media del cerebelo en unidades Hounsfield en el intervalo de valores que corresponden a hiperemia. Estos cambios fueron dinámicos y cuando se resolvió la hiperemia y la densidad cerebelosa volvió a los niveles basales, el cuarto ventrículo se volvió a expandir y la paciente se recuperó neurológicamente.ConclusionesEste estudio demuestra la utilidad del análisis cuantitativo de imágenes de la TC en el contexto de las alteraciones hemodinámicas posteriores a la resección de una MAV. El análisis densitométrico de la TC demostró que los cambios hiperémicos, pero no los isquémicos, variaron con el tiempo de evolución y eran responsables del swelling y la hemorragia que condicionaban el estado neurológico y la evolución del paciente (AU)

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.

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.

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.

Case Report: SARS-CoV-2 Infection-Are We Redeemed? A Report of Candida Spondylodiscitis as a Late Complication.

Background: We describe a case of candida spondylodiscitis secondary to coronavirus disease (COVID-19). Case report: A 47-year-old man diagnosed with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) required prolonged admission to the intensive care unit (ICU). Four months later, he was diagnosed with thoracic candida spondylodiscitis. Medical management was insufficient, so he eventually underwent surgery. Discussions: Fungal infections seem to be more likely in patients with COVID-19, but it is unknown whether they are directly attributed to COVID-19 or other surrounding factors. Regardless of the answer, the diagnosis is complicated, and the mortality rate is high. Lessons: COVID-19 is posing a challenge to the society, and new and unexpected diseases that had once disappeared have risen again. It is our duty to suspect them and to treat them in the most effective way possible.

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.

Implant Microbial Colonization Detected by Sonication as a Cause for Spinal Device Failure: A Prospective Study.

STUDY DESIGN: A prospective single center observational study. OBJECTIVES: The aim of this study was to examine the potential role of sonication in the diagnosis of low-grade infections and its association with pedicle screw (PS) loosening, and to describe risk factors and radiological findings associated with spinal implant infection. SUMMARY OF BACKGROUND DATA: Although PS loosening has mainly been attributed to mechanical overload, implant colonization and biofilm formation have recently been suggested. Culturing of sonication fluid implants is promising in the field of spine instrumentation infection, but little data are available. METHODS: We prospectively included all patients who were subjected to implant removal. PS loosening was assessed with computed tomography (CT) scan. Different clinical and radiological parameters which could serve as indicators of implant infection were studied. RESULTS: Thirty-eight patients were included in the study and 11 of them (29%) had a positive sonication result. Patients with spinal implant infection were associated with screw loosening (P = 0.005). Particularly, those screws with a positive microbiological culture showed signs of screw loosening in the preoperative CT scan (P < 0.001). Our results also showed that radiological screw loosening at L1-L3 level, and loosened larger constructs were associated with screw microbial colonization. The most common isolated microorganisms were coagulase-negative staphylococci and Cutibacterium acnes. An implant-based multivariate analysis indicated that screw loosening, the absence of prophylactic cefazolin, ICU hospitalization, screw breakage, and L1-L3 spine level were independent risk factors for implant-associated infection. Our model exhibited a high predictive power with an area under the curve of 0.937. CONCLUSION: As clinical presentation of deep implant chronic infection is unspecific, consideration of these factors enables preoperative prediction and risk stratification of implant colonization, thus helping patient's management.Level of Evidence: 3.