Surgical or endovascular management of ruptured intracranial aneurysms: an agreement study

J Neurosurg 131:25–31, 2019

Ruptured intracranial aneurysms (RIAs) can be managed surgically or endovascularly. In this study, the authors aimed to measure the interobserver agreement in selecting the best management option for various patients with an RIA.

METHODS The authors constructed an electronic portfolio of 42 cases of RIA in which an angiographic image along with a brief clinical vignette for each patient were displayed. Undisclosed to the responders was that the RIAs had been categorized as International Subarachnoid Aneurysm Trial (ISAT) (small, anterior-circulation, non–middle cerebral artery location, n = 18) and non-ISAT (n = 22) aneurysms; the non-ISAT group also included 2 basilar apex aneurysms for which a high number of endovascular choices was expected. The portfolio was sent to 132 clinicians who manage pa- tients with RIAs and circulated to members of an American surgical association. Judges were asked to choose between surgical and endovascular management, to indicate their level of confidence in the choice of treatment on a quantitative 0–10 scale, and to determine whether they would include the patient in a randomized trial in which both treatments are compared. Eleven clinicians were asked to respond twice at least 1 month apart. Responses were analyzed using kappa statistics.

RESULTS Eighty-five clinicians (58 cerebrovascular surgeons, 21 interventional neuroradiologists, and 6 interventional neurologists) answered the questionnaire. Overall, endovascular management was chosen more frequently (n = 2136 [59.8%] of 3570 answers). The proportions of decisions to clip were significantly higher for non-ISAT (50.8%) than for ISAT (26.2%) aneurysms (p = 0.0003). Interjudge agreement was only fair (kappa 0.210, 95% CI 0.158–0.276) for all cases and judges, despite high confidence levels (mean score > 8 for all cases). Agreement was no better within sub- groups of clinicians with the same specialty, years of experience, or location of practice or across capability groups (ability to clip or coil, or both). When agreement was defined as > 80% of responders choosing the same option, agreement occurred for only 7 of 40 cases, all of which were ISAT aneurysms, for which coiling was preferred.

CONCLUSIONS Agreement between clinicians regarding the best management option was infrequent but centered around coiling for some ISAT aneurysms. Surgical clipping was chosen more frequently for non-ISAT aneurysms than for ISAT aneurysms. Patients with such an aneurysm might be candidates for inclusion in randomized trials.

Amygdala and Hypothalamus: Historical Overview With Focus on Aggression

Neurosurgery, 85, 1: 11–30, 2019

Aggressiveness has a high prevalence in psychiatric patients and is a major health problem. Two brain areas involved in the neural network of aggressive behavior are the amygdala and the hypothalamus.

While pharmacological treatments are effective in most patients, some do not properly respond to conventional therapies and are considered medically refractory. In this population, surgical procedures (ie, stereotactic lesions and deep brain stimulation) have been performed in an attempt to improve symptomatology and quality of life.

Clinical results obtained after surgery are difficult to interpret, and the mechanisms responsible for postoperative reductions in aggressive behavior are unknown.

We review the rationale and neurobiological characteristics that may help to explain why functional neurosurgery has been proposed to control aggressive behavior.

Cavernous angiomas: deconstructing a neurosurgical disease

J Neurosurg 131:1–13, 2019

Cavernous angioma (CA) is also known as cavernoma, cavernous hemangioma, and cerebral cavernous malformation (CCM) (National Library of Medicine Medical Subject heading unique ID D006392). In its sporadic form, CA occurs as a solitary hemorrhagic vascular lesion or as clustered lesions associated with a developmental venous anomaly. In its autosomal dominant familial form (Online Mendelian Inheritance in Man #116860), CA is caused by a heterozygous germ-line loss-of-function mutation in one of three genes—CCM1/KRIT1, CCM2/Malcavernin, and CCM3/PDCD10—causing multifocal lesions throughout the brain and spinal cord.

In this paper, the authors review the cardinal features of CA’s disease pathology and clinical radiological features. They summarize key aspects of CA’s natural history and broad elements of evidence-based management guidelines, including surgery. The authors also discuss evidence of similar genetic defects in sporadic and familial lesions, consequences of CCM gene loss in different tissues at various stages of development, and implications regarding the pathobiology of CAs.

The concept of CA with symptomatic hemorrhage (CASH) is presented as well as its relevance to clinical care and research in the field. Pathobiological mechanisms related to CA include inflammation and immune-mediated processes, angiogenesis and vascular permeability, microbiome driven factors, and lesional anticoagulant domains. These mechanisms have motivated the development of imaging and plasma biomarkers of relevant disease behavior and promising therapeutic targets.

The spectrum of discoveries about CA and their implications endorse CA as a paradigm for deconstructing a neurosurgical disease.


Three-year results from a randomized trial of lumbar discectomy with annulus fibrosus occlusion in patients at high risk for reherniation

Acta Neurochirurgica (2019) 161:1389–1396

A larger defect in the annulus fibrosus following lumbar discectomy is a well-known risk factor for reherniation. Procedures intended to prevent reherniation by sealing or occluding the annular defect warrant study in high-risk patients. This study sought to determine 3-year results of lumbar discectomy with a bone-anchored annular closure device (ACD) or lumbar discectomy only (controls) in patients at high risk for reherniation.

Methods This multicenter randomized trial enrolled patients with sciatica due to lumbar intervertebral disc herniation who failed conservative treatment. Patients with large annular defects after lumbar limited microdiscectomy were intraoperatively randomly assigned to receive ACD or control. Clinical and imaging follow-up was performed at routine intervals over 3 years. Main outcomes included rate of reherniations, reoperations, and endplate changes; leg and back pain scores on a visual analogue scale; Oswestry Disability Index (ODI); Physical Component Summary (PCS) and Mental Component Summary (MCS) scores from the SF-36; and adverse events adjudicated by a data safety monitoring board.

Results Among 554 randomized patients, the modified intent-to-treat population consisted of 272 patients in which ACD implantation was attempted and 278 receiving control; device implantation was not attempted in 4 patients assigned to ACD. Outcomes at 3 years favored ACD for symptomatic reherniation (14.8% vs. 29.5%; P < 0.001), reoperation (11.0% vs. 19.3%; P = 0.007), leg pain (21 vs. 30; P < 0.01), back pain (23 vs. 30; P = 0.01), ODI (18 vs. 23; P = 0.02), PCS (47 vs. 44; P < 0.01), and MCS (52 vs. 49; P < 0.01). The frequency of all-cause serious adverse events was comparable between groups (42.3% vs. 44.5%; P = 0.61).

Conclusions The addition of a bone-anchored ACD in patients with large annular defects following lumbar discectomy reduces the risk of reherniation and reoperation, and has a similar safety profile over 3-year follow-up compared with lumbar limited discectomy only.


The biophysical role of hemodynamics in the pathogenesis of cerebral aneurysm formation and rupture

Neurosurg Focus 47 (1):E11, 2019

The pathogenesis of intracranial aneurysms remains complex and multifactorial. While vascular, genetic, and epidemio- logical factors play a role, nascent aneurysm formation is believed to be induced by hemodynamic forces. Hemodynamic stresses and vascular insults lead to additional aneurysm and vessel remodeling. Advanced imaging techniques allow us to better define the roles of aneurysm and vessel morphology and hemodynamic parameters, such as wall shear stress, oscillatory shear index, and patterns of flow on aneurysm formation, growth, and rupture. While a complete understand- ing of the interplay between these hemodynamic variables remains elusive, the authors review the efforts that have been made over the past several decades in an attempt to elucidate the physical and biological interactions that govern aneurysm pathophysiology. Furthermore, the current clinical utility of hemodynamics in predicting aneurysm rupture is discussed.

Numerical Analysis of Bifurcation Angles and Branch Patterns in Intracranial Aneurysm Formation

Neurosurgery 85 (1): E31–E39. 2019

Hemodynamic factors, especially wall shear stress (WSS), are generally thought to play an important role in intracranial aneurysm (IA) formation. IAs frequently occur at bifurcation apices, where the vessels are exposed to the impact of WSS.

OBJECTIVE: To elucidate the relationship between bifurcation geometry and WSS for IA formation.

METHODS: Twenty-one bifurcation models varying in branch angles and branch diameters were made with 3-dimensional computer-aided design software. In all models, the value of maximum WSS (WSSMAX), the area of high WSS (AREA), and the magnitude of wall shear force over AREA (|Fw |) were investigated by the steady-flow simulation of computational fluid dynamics.

RESULTS: On the basis of statistical analysis, WSSMAX tended to be high when the bifurcation angle and/or branch diameter was small. AREA and |F⃗ | significantly increase as the bifurcation and/or the branch angle became larger.

CONCLUSION: The magnitude of WSS strongly correlated with bifurcation geometry. In addition to high WSS, AREA and |F⃗ | were thought to affect IA formation. Observed bifurcation geometry may predict IA formation. Large branch angles and small branch may increase the risk of IA formation.

Iterative Surgical Resections of Diffuse Glioma With Awake Mapping: How to Deal With Cortical Plasticity and Connectomal Constraints?

Neurosurgery 85(1):105–116. 2019

In diffuse glioma, a multistage approach with iterative tailored surgical resections can be considered.
OBJECTIVE: To compare results of iterative intrasurgical brain mappings to investigate the potential and limitation of neuroplasticity at the individual stage, and to highlight to what extent it can influence the therapeutic strategy.
METHODS: Glioma patients who underwent 2 consecutive awake surgeries with cortical and subcortical stimulation were classified into group 1 (n = 23) if cortical mappings exhibited high level of plasticity (displacement of ≥2 sites) or into group 2 (n = 19) with low level of plasticity.
RESULTS: Clinical characteristics did not differ significantly between both groups. The borders of the tumors were mostly sharp in group 1 (82.6%) and rather indistinct in group 2 (84.2%), (P = .00001). Tumor remnants were more often cortical (± subcortical) in group 1 (39.1%) and more often purely subcortical in group 2 (68.4%; P = .009). In group 1, the time needed to recover independence was significantly shorter at reoperation (37.6 h vs 78.3 h after the first surgery, P = .00003) while this difference was not significant in group 2. The iterative extents of resection (EOR) remain comparable in group 1 (94% vs 92%, P = .40) but were significantly smaller in group 2 at reoperation (94% vs 88%, P = .05).
CONCLUSION: More efficient plasticity mechanisms are facilitated by cortical tumors with sharp borders, are associated with an increase of EOR at reoperation and with earlier functional recovery. Tumoral invasion of the white matter tracts represents the main limitation of neuroplasticity: this connectomal constraint limits EOR during second surgery.

Investigating the utility of intraoperative neurophysiological monitoring for anterior cervical discectomy and fusion: analysis of over 140,000 cases from the National (Nationwide) Inpatient Sample data set

J Neurosurg Spine 31:76–86, 2019

Intraoperative neurophysiological monitoring (IONM) is a useful adjunct in spine surgery, with proven benefit in scoliosis-correction surgery. However, its utility for anterior cervical discectomy and fusion (ACDF) is unclear, as there are few head-to-head comparisons of ACDF outcomes with and without the use of IONM. The authors sought to evaluate the impact of IONM on the safety and cost of ACDF.

METHODS This was a retrospective analysis of data from the National (Nationwide) Inpatient Sample of the Healthcare Cost and Utilization Project from 2009 to 2013. Patients with a primary procedure code for ACDF were identified, and diagnosis codes were searched to identify cases with postoperative neurological complications. The authors performed univariate and multivariate logistic regression for postoperative neurological complications with use of IONM as the in- dependent variable; additional covariates included age, sex, surgical indication, multilevel fusion, Charlson Comorbidity Index (CCI) score, and admission type. They also conducted propensity score matching in a 1:1 ratio (nearest neighbor) with the use of IONM as the treatment indicator and the aforementioned variables as covariates. In the propensity score–matched cohort, they compared neurological complications, length of stay (LOS), and hospital charges (in US dollars).

RESULTS A total of 141,007 ACDF operations were identified. IONM was used in 9540 cases (6.8%). No significant association was found between neurological complications and use of IONM on univariate analysis (OR 0.80, p = 0.39) or multivariate regression (OR 0.82, p = 0.45). By contrast, age ≥ 65 years, multilevel fusion, CCI score > 0, and a non- elective admission were associated with greater incidence of neurological complication. The propensity score–matched cohort consisted of 18,760 patients who underwent ACDF with (n = 9380) or without (n = 9380) IONM. Rates of neurological complication were comparable between IONM and non-IONM (0.17% vs 0.22%, p = 0.41) groups. IONM and non-IONM groups had a comparable proportion of patients with LOS ≥ 2 days (19% vs 18%, p = 0.15). The use of IONM was associated with an additional $6843 (p < 0.01) in hospital charges.

CONCLUSIONS The use of IONM was not associated with a reduced rate of neurological complications following ACDF. Limitations of the data source precluded a specific assessment of the effectiveness of IONM in preventing neuro- logical complications in patients with more complex pathology (i.e., ossification of the posterior longitudinal ligament or cervical deformity).

Ruptured PICA aneurysms: presentation and treatment outcomes compared to other posterior circulation aneurysms

Acta Neurochirurgica (2019) 161:1325–1334

Aneurysms of the posterior inferior cerebellar artery (PICA) are relatively uncommon and evidence is sparse about patients presenting with ruptured PICA aneurysms. We performed an analysis of the Swiss SOS national registry to describe clinical presentation, treatment pattern, and neurological outcome of patients with ruptured PICA aneurysms compared with other ruptured posterior circulation (PC) aneurysms.

Methods This was a retrospective analysis of anonymized data from the Swiss SOS registry (Swiss Study on Aneurysmal Subarachnoid Hemorrhage; 2009–2014). Patients with ruptured PC aneurysms were subdivided into a PICA and non-PICA group. Clinical, radiological, and treatment-related variables were identified, and their impact on the neurological outcome was determined in terms of modified Rankin score at discharge and at 1 year of follow-up for the two groups.

Results Data from 1864 aneurysmal subarachnoid hemorrhage patients were reviewed. There were 264 patients with a ruptured PC aneurysm. Seventy-four PICA aneurysms represented 28% of the series; clinical and radiological characteristics at admission were comparable between the PICA and non-PICA group. Surgical treatment was accomplished in 28% of patients in the PICA group and in the 4.8% of patients in the non-PICA group. No statistically significant difference was found between the two groups in terms of complications after treatment. Hydrocephalus requiring definitive shunt was needed in 21.6% of PICA patients (p = 0.6); cranial nerve deficit was present in average a quarter of the patients in both PICA and non-PICA group with no statistical difference (p = 0.3). A more favorable outcome (66.2%) was reported in the PICA group at discharge (p < 0.05) but this difference faded over time with a similar neurological outcome at 1-year follow-up (p = 0.09) between both PICA and non- PICA group. The Kaplan-Meyer estimation showed no significant difference in the mortality rate between both groups (p = 0.08).

Conclusions In the present study, patients with ruptured PICA aneurysms had a favorable neurological outcome in more than two thirds of cases, similar to patients with other ruptured PC aneurysms. Surgical treatment remains a valid option in a third of cases with ruptured PICA aneurysms.

Peritumoral Edema/Tumor Volume Ratio: A Strong Survival Predictor for Posterior Fossa Metastases

Neurosurgery, Volume 85, Issue 1, July 2019, Pages 117–125

Twenty percent of all brain metastases (BM) occur in the posterior fossa (PF). Radiotherapy sometimes associated with surgical resection remains the therapeutic option, while Karnovsky performance status and graded prognostic assessment (GPA) are the best preoperative survival prognostic factors.

OBJECTIVE: To explore the prognostic role of peritumoral brain edema in the PF, which has never been explored though its role in supratentorial BM has been debated.

METHODS: A total of 120 patients diagnosed with PF metastasis who underwent surgical resection were included retrospectively in this analysis. Clinical data were retrieved from electronic patient medical files. The tumor volumes and their associated edema were calculated via manual delineation; subsequently the edema/tumor volume ratio was determined.

RESULTS: In multivariate analysis with Cox multivariate proportional hazard model, the edema to tumor volumes ratio (hazard ratio [HR]: 1.727, 95% confidence interval [CI] 1.427- 2.083; P < .0001) was identified as a new strong independent prognosis factor on overall survival (OS) whereas edema volume alone was not (P = .469). Moreover, BM complete resection (HR: 0.447, 95% CI 0.277-0.719; P < .001), low (0-1) World Health Organization status at diagnosis (HR: 2.109, 95% CI 1.481-3.015; P < .0001), high GPA class at diagnosis (HR: 1.77, 95% CI 0.9-2.9; P < .04), and postoperative brain irradiation (HR: 2.019, 95% CI 1.213-3.361; P < .007] were all confirmed as independent predictive factors for survival.

CONCLUSION: The edema/tumor ratio appears to greatly influence OS in patients suffering from PF metastases unlike the extent of edema alone. This easily determined as well as strong prognostic factor could be used as an interesting tool in clinical practice to help the management of these patients.

Augmented reality–assisted pedicle screw insertion

J Neurosurg Spine 31:139–146, 2019

Augmented reality (AR) is a novel technology that has the potential to increase the technical feasibility, accuracy, and safety of conventional manual and robotic computer-navigated pedicle insertion methods. Visual data are directly projected to the operator’s retina and overlaid onto the surgical field, thereby removing the requirement to shift attention to a remote display. The objective of this study was to assess the comparative accuracy of AR-assisted pedicle screw insertion in comparison to conventional pedicle screw insertion methods.

METHODS Five cadaveric male torsos were instrumented bilaterally from T6 to L5 for a total of 120 inserted pedicle screws. Postprocedural CT scans were obtained, and screw insertion accuracy was graded by 2 independent neuroradiologists using both the Gertzbein scale (GS) and a combination of that scale and the Heary classification, referred to in this paper as the Heary-Gertzbein scale (HGS). Non-inferiority analysis was performed, comparing the accuracy to freehand, manual computer-navigated, and robotics-assisted computer-navigated insertion accuracy rates reported in the literature. User experience analysis was conducted via a user experience questionnaire filled out by operators after the procedures.

RESULTS The overall screw placement accuracy achieved with the AR system was 96.7% based on the HGS and 94.6% based on the GS. Insertion accuracy was non-inferior to accuracy reported for manual computer-navigated pedicle insertion based on both the GS and the HGS scores. When compared to accuracy reported for robotics-assisted computer-navigated insertion, accuracy achieved with the AR system was found to be non-inferior when assessed with the GS, but superior when assessed with the HGS. Last, accuracy results achieved with the AR system were found to be superior to results obtained with freehand insertion based on both the HGS and the GS scores. Accuracy results were not found to be inferior in any comparison. User experience analysis yielded “excellent” usability classification.

CONCLUSIONS AR-assisted pedicle screw insertion is a technically feasible and accurate insertion method.


Morphological Variables Associated With Ruptured Middle Cerebral Artery Aneurysms

Neurosurgery, Volume 85, Issue 1, July 2019, Pages 75–83

Geometric factors of intracranial aneurysms and surrounding vasculature could affect the risk of aneurysm rupture. However, large-scale assessments of morphological parameters correlated with intracranial aneurysm rupture in a location-specific manner are scarce.

OBJECTIVE: To investigate the morphological characteristics associated with ruptured middle cerebral artery (MCA) aneurysms.

METHODS: Five hundred sixty-one patients with 638 MCA aneurysms diagnosed between 1990 and 2016 who had available computed tomography angiography (CTA) were included in this study. CTAs were evaluated using the Vitrea Advanced Visualization software for 3-dimensional (3D) reconstruction. Morphological parameters examined in each model included aneurysm projection, wall irregularity, presence of a daughter dome, presence of hypoplastic or aplastic A1 arteries and hypoplastic or fetal posterior communicating arteries (PCoA), aneurysm height and width, neck diameter, bottleneck factor, aspect and size ratio, height/width ratio, and diameters and angles of surrounding parent and daughter vessels. Univariable and multivariable statistical analyses were performed to determine the association of morphological characteristics with rupture of MCA aneurysms. Logistic regression was used to build a predictive MCA score.

RESULTS: Greater bottleneck and size ratio, and irregular, multilobed, temporally projecting MCA aneurysms are associated with higher rupture risk, whereas higher M1/M2 ratio, larger width, and the presence of an ipsilateral or bilateral hypoplastic PCoA were inversely associated with rupture. The MCA score had good predictive capacity with area under the receiver operating curve = 0.88.
CONCLUSION: These practical morphological parameters specific to MCA aneurysms are easy to assess when examining 3D reconstructions of unruptured aneurysms and could aid in risk evaluation in these patients.

Universal fluorescence module for intraoperative fluorescein angiography

Acta Neurochirurgica (2019) 161:1343–1348

Even in specialized centers, suboptimal aneurysm clipping can be as high as 12%. Intraoperative fluorescence angiography with indocyanine green and, more recently, fluorescein sodium have been shown to be a good method for intraop- erative flow assessment. However, the cost with the apparatus it entails limits its widespread use.

We have developed a low-cost universal fluorescence module (FM) designed to visualize fluorescein and perform intraoperative angiography. The purpose of this paper is to describe this device as well as to present our early experience with its use in the treatment of cerebral aneurysms.

Method A FM was designed and built using a cyan-blue narrow bandpass (460 to 490 nm) excitation filter and a yellow-orange longpass (blocking wavelengths under 520 nm) barrier filter mounted on a 3D-printed holding tray in a specific disposition to perfectly match the light source and the objective lens of the surgical microscope. It allowed switching from white light to fluorescence mode in a simple and sterile fashion. Its perfect attachment to the microscope was possible by reusing the lens fittings extracted from used original drape sets that would otherwise be discarded. Four patients underwent aneurysm clipping using the FM at two institutions from April to September 2018.

Results A bright green fluorescence against a dark background was observed after intravenous bolus of fluorescein. Blood vessels became obviously distinct from non-contrast-filled structures such as clipped aneurysms and the brain. Vascular anatomy could be appreciated without any distortion, including perforating arteries.

Conclusions Intraoperative fluorescence angiography was successfully performed with the use of this universal FM after intra- venous injection of fluorescein sodium. This simple and low-cost device may be useful in resource-limited centers, where other sorts of intraoperative angiography are not available.

Pediatric Supratentorial Ependymoma: Surgical, Clinical, and Molecular Analysis

Neurosurgery 85:41–49, 2019

Pediatric supratentorial ependymomas (SEs) have distinct molecular and behavioral differences from their infratentorial counterparts.

OBJECTIVE: To present our experience with pediatric SEs over a 24-yr period.

METHODS: Clinical, operative, and radiographic information was abstracted retrospectively. Our primary outcomes were progression-free survival (PFS) and overall survival (OS). Detection of C11or f95-RELA rearrangement was performed using interphase fluorescence in situ hybridization (iFISH).

RESULTS: Seventy-three patients were identified (41 female, 32 male); median age was 6.7 yrs (range, 1 mo-18.8 yr); median follow-up was 8.3 yrs (range, 2.0-26.3). Fifty-eight (79.5%) of 73 patients underwent gross total resection (GTR); no patient with subtotal resection had greater than 1 cm3 of residual tumor; 42 patients (57.5%) experienced subsequent disease progression with 17 patients ultimately dying of their disease. Median PFS was 3.7 yrs. Molecular analysis was available for 51 patients (70%). On bivariate analysis, PFS and OS were not statistically affected by age, tumor grade, or extent of resection, although there was a clinically significant trend for the latter in favor of aggressive resection on PFS (P = .061). Children with RELA fusion had significantly higher PFS (P = .013) than those without, although there was no difference in OS when compared with those with no C11orf95-RELA fusion or C11orf95 gene rearrangement alone.

CONCLUSION: In our series, GTR may be associated with better PFS, but did not impact OS. Surprisingly, RELA fusion was not found to be a negative prognostic factor, raising the possibility that the deleterious effects may be overcome by aggressive resection.

Effectiveness of anterior cervical discectomy with or without interbody fusion and arthroplasty in the treatment of cervical disc herniation; a double-blinded randomised controlled trial

The Spine J Volume 19, Issue 6, Pages 965–975. 2019

Motion preserving anterior cervical disc arthroplasty (ACDA) in patients with cervical radiculopathy was introduced to prevent symptomatic adjacent disc degeneration as compared to anterior cervical discectomy and fusion (ACDF). Prior reports suggest that ACDF is not more effective than anterior cervical discectomy (ACD) alone for the treatment of cervical radiculopathy.

Purpose: To evaluate whether patients with cervical radiculopathy due to a herniated disc benefit more from undergoing ACDA, ACDF, or ACD in terms of clinical outcome measured by the Neck Disability Index (NDI).

Study design: Double-blinded randomized controlled trial

Methods: One hundred-nine patients with one level herniated disc were randomized to one of the following treatments: ACDA, ACDF with intervertebral cage, ACD without fusion. Clinical and radiological outcome was measured by NDI, Visual Analogue Scale (VAS) neck pain, VAS arm pain, SF36, EQ-5D, patients’ self-reported perceived recovery, radiographic cervical curvature, and adjacent segment degeneration (ASD) parameters at baseline and until two years after surgery. BBraun Medical paid €298.837 to cover the costs for research nurses.

Results: The NDI declined from 41 to 47 points at baseline to 19±15 in the ACD group, 19± 18 in the ACDF group, and 20±22 in the ACDA group after surgery (p=0.929). VAS arm and neck pain declined to half its baseline value and decreased below the critical value of 40 mm. Quality of life, measured by the EQ-5D, increased in all three groups. ASD parameters were comparable in all three groups as well. No statistical differences were demonstrated between the treatment groups.

Conclusions: The hypothesis that ACDA would lead to superior clinical outcome in comparison to ACDF or ACD could not be confirmed during a two-year follow-up time period. Single level ACD without implanting an intervertebral device may be a reasonable alternative to ACDF or ACDA.

MRI combined with PET-CT of different tracers to improve the accuracy of glioma diagnosis

Neurosurg Rev (2019) 42:185–195

Based on studies focusing on positron emission tomography (PET)-computed tomography (CT) combined with magnetic resonance imaging (MRI) in the diagnosis of glioma, we conducted a systematic review and meta-analysis evaluating the pros and cons and the accuracy of different examinations. PubMed and Cochrane Library were searched. The search was conducted until April 2017. Two reviewers independently conducted the literature search according to the criteria set initially. Based on the exclusion criteria, 15 articles are included in this study.

Of all studies that used MRI examination, there are five involving 18F-fluorodeoxyglucose- PET, five involving 11C-methionine-PET, five involving 18F-fluoro-ethyl-tyrosine-PET, and three involving 18Ffluorothymidine- PET. Due to the limitations such as lack of data, small sample size, and unrepresentative studies, we use a non-quantitative methodology.

MRI examination can provide the anatomy information of glioma more clearly. PET-CT examinations based on tumor metabolism using different tracers have more advantages in determining the degree of glioma malignancy and boundaries. However, information provided by PET-Craneotomía of different tracers is not the same. With respect to the novel hybrid MRI/PET examination equipment proposed in recent years, the combination of MRI and PET-CT can definitively improve the diagnostic accuracy of glioma.

Somatotopy and Organization of Spinothalamic Tracts in the Human Cervical Spinal Cord

Neurosurgery, Volume 84, Issue 6, June 2019, Pages E311–E317

Understanding spinothalamic tract anatomy may improve lesioning and outcomes in patients undergoing percutaneous cordotomy.

OBJECTIVE: To investigate somatotopy and anatomical organization of spinothalamic tracts in the human cervical spinal cord.

METHODS: Patients with intractable cancer pain undergoing cordotomy underwent preoperative and postoperative quantitative sensory testing for sharp pain and heat pain on day 1 and 7 after cordotomy. Intraoperative sensory stimulation was performed with computed tomography (CT) imaging to confirm the location of the radiofrequency electrode during cordotomy. Postoperative magnetic resonance (MR) imaging was performed to define the location of the lesion.

RESULTS: Twelve patientswere studied, and intraoperative sensory stimulation combined with CT imaging revealed a somatotopy where fibers from the legs were posterolateral to fibers from the hand. Sharpness detection thresholds were significantly elevated in the area of maximum pain on postoperative day 1 (P = .01). Heat pain thresholds for all areas were not elevated significantly on postoperative day 1, or postoperative day 7. MR imaging confirmed that the cordotomy lesion was in the anterolateral quadrant, and in this location the lesion had a sustained effect on sharp pain but a transient impact on heat pain.

CONCLUSION: In the high cervical spinal cord, spinothalamic fibers mediating sharp pain for the arms are located ventromedial to fibers for the legs, and these fibers are spatially distinct from fibers that mediate heat pain.

Petrosal Meningiomas: Factors Affecting Outcome and the Role of Intraoperative Multimodal Assistance to Microsurgery

Neurosurgery, Volume 84, Issue 6, June 2019, Pages 1313–1324

Petrous meningiomas (PMs) represent a subset of posterior fossa tumors accounting for ∼8% of all intracranial meningiomas. Surgical treatment of PMs is challenging because of their relationships with vital neurovascular structures of the cerebellopontine angle.

OBJECTIVE: To investigate independent pre- and intraoperative predictors of PM surgery outcome.

METHODS:We reviewed the surgical and outcome data of patients who underwent microsurgical resection of PMs from 1997 to 2016. From 2007 onward, a multimodal intraoperative protocol consisting of intraoperative neuromonitoring (IONM), endoscopy, and indocyanine green (ICG) videoangiography was applied. Outcome variables included extent of resection, Karnofsky performance status (KPS), overall survival, and progression-free survival (PFS).

RESULTS: A total of 54 patients were included. Independent predictors of gross total resection (GTR) included retromeatal location (P < .0175; odds ratio [OR] 4.05), absence of brainstem compression (P < .02; OR 3.55), and histological WHO grade I (P < .001; OR 3.47). Nongiant size (P < .012; OR 4.38), and WHO grade I (P < .0001; OR 7.7) were independent predictors of stable or improved KPS. The use of multimodal intraoperative tools to assist surgery independently predicted GTR (P < .002; OR 6.8) and good KPS (P < .018; OR 4.23). Nongiant size (P = .01) and WHO grade I (P = .002) were significantly associated with increased PFS.

CONCLUSION: Notwithstanding the limitations of a retrospective study, our results suggest that support of microsurgery by a combination of IONM, endoscopy, and ICG videoangiography may improve patient outcome in PM surgery.

Could propranolol be beneficial in adult cerebral cavernous malformations?

Neurosurgical Review (2019) 42:403–408

Surgery is the only therapeutic option for cerebral cavernous malformations (CCM) and is proposed, whenever possible, after haemorrhagic events, neurological symptoms, or epilepsy, radiosurgery being a controversial alternative in some cases. However, there is no treatment for non-accessible lesions, such as brainstem CCM, multiple CCM, or those located in functional areas.

Propranolol, a non-selective beta-blocker used as first-line treatment for infantile haemangiomas, has proved spectacularly effective in a few cases of adult patients with CCM.

We herein review the histological, in vitro data and clinical findings that support the idea of propranolol as a potential treatment for CCM. Since one retrospective study has not been conclusive, we support the idea that prospective trials are necessary.