Quantification of cauda equina nerve root dispersion through radiomics features in weight-bearing MRI in normal subjects and spinal canal stenosis patients.

OBJECTIVE: To quantify the distribution of cauda equina nerve roots in supine and upright positions using manual measurements and radiomics features both in normal subjects and in lumbar spinal canal stenosis (LSCS) patients. METHODS: We retrospectively recruited patients who underwent weight-bearing MRI in supine and upright positions for back pain. 3D T2-weighted isotropic acquisition (3D-HYCE) sequences were used to develop a 3D convolutional neural network for identification and segmentation of lumbar vertebrae. Para-axial reformatted images perpendicular to the spinal canal and parallel to each vertebral endplate were automatically extracted. From each level, we computed the maximum antero-posterior (AP) and latero-lateral (LL) dispersion of nerve roots; further, radiomics features were extracted to quantify standardized metrics of nerve root distribution. RESULTS: We included 16 patients with LSCS and 20 normal subjects. In normal subjects, nerve root AP dispersion significantly increased from supine to upright position (p < 0.001, L2-L5 levels), and radiomics features showed an increase in non-uniformity. In LSCS subjects, in the upright position AP dispersion of nerve roots and entropy-related features increased caudally to the stenosis level (p < 0.001) and decreased cranially (p < 0.001). Moreover, entropy-related radiomics features negatively correlated with pre-operative Pain Numerical Rating Scale. Comparison between normal subjects and LSCS patients showed a difference in AP dispersion and increase of variance cranially to the stenosis level (p < 0.001) in the upright position. CONCLUSIONS: Nerve root distribution inside the dural sac changed between supine and upright positions, and radiomics features were able to quantify the differences between normal and LSCS subjects. CLINICAL RELEVANCE STATEMENT: The distribution of cauda equina nerve roots and the redundant nerve root sign significantly varies between supine and upright positions in normal subjects and spinal canal stenosis patients, respectively. Radiomics features quantify nerve root dispersion and correlates with pain severity. KEY POINTS: • Weight-bearing MRI depicts spatial distribution of the cauda equina in both supine and upright positions in normal subjects and spinal stenosis patients. • Radiomics features can quantify the effects of spinal stenosis on the dispersion of the cauda equina in the dural sac. • In the orthostatic position, dispersion of nerve roots is different in lumbar spinal stenosis patients compared to that in normal subjects; entropy-related features negatively correlated with pre-operative Pain Numerical Rating Scale.

CT-based radiomics can identify physiological modifications of bone structure related to subjects' age and sex.

PURPOSE: Radiomics of vertebral bone structure is a promising technique for identification of osteoporosis. We aimed at assessing the accuracy of machine learning in identifying physiological changes related to subjects' sex and age through analysis of radiomics features from CT images of lumbar vertebrae, and define its generalizability across different scanners. MATERIALS AND METHODS: We annotated spherical volumes-of-interest (VOIs) in the center of the vertebral body for each lumbar vertebra in 233 subjects who had undergone lumbar CT for back pain on 3 different scanners, and we evaluated radiomics features from each VOI. Subjects with history of bone metabolism disorders, cancer, and vertebral fractures were excluded. We performed machine learning classification and regression models to identify subjects' sex and age respectively, and we computed a voting model which combined predictions. RESULTS: The model was trained on 173 subjects and tested on an internal validation dataset of 60. Radiomics was able to identify subjects' sex within single CT scanner (ROC AUC: up to 0.9714), with lower performance on the combined dataset of the 3 scanners (ROC AUC: 0.5545). Higher consistency among different scanners was found in identification of subjects' age (R2 0.568 on all scanners, MAD 7.232 years), with highest results on a single CT scanner (R2 0.667, MAD 3.296 years). CONCLUSION: Radiomics features are able to extract biometric data from lumbar trabecular bone, and determine bone modifications related to subjects' sex and age with great accuracy. However, acquisition from different CT scanners reduces the accuracy of the analysis.

Vertebral Fractures Associated with Spinal Sagittal Imbalance and Quality of Life in Acromegaly: A Radiographic Study with EOS 2D/3D Technology.

INTRODUCTION: Acromegaly is commonly complicated by arthropathy and skeletal fragility with high risk of vertebral fractures (VFs). OBJECTIVE: This study aimed to assess whether VFs may be associated with sagittal spine deformities, arthropathy, impaired quality of life (QoL), pain, and disability. METHODS: Thirty-eight patients with acromegaly (median age: 55 years, 20 males) and 38 matched control subjects were evaluated by a low-dose sagittal and coronal planes, X-ray imaging system (EOS®-2D/3D) for morphometric VFs, radiological signs of spine arthropathy, and spine deformities (Cobb thoracic index ≥40°, pelvic incidence minus lumbar lordosis ≥10°, pelvic tilt >20°, and sagittal vertical axis ≥4 cm) determining sagittal spine imbalance. Acromegalic patients were also evaluated by questionnaires for QoL (Acromegaly QoL Questionnaire [AcroQoL] and Short Form-36 [SF-36]) and pain and disability (Western Ontario and McMaster University [WOMAC]). RESULTS: Acromegalic patients showed higher prevalence of thoracic hyperkyphosis (i.e., Cobb thoracic index ≥40°; p = 0.04) and pelvic tilt >20° (p = 0.02) than control subjects. VFs were found in 34.2% of acromegalic patients (p = 0.003 vs. control subjects), in relationship with higher prevalence of hyperkyphosis (p = 0.03), pelvic tilt >20° (p = 0.04), sagittal vertical axis ≥4 cm (p = 0.03), and moderate/severe subchondral degeneration (p = 0.01). Moreover, patients with VFs had lower AcroQoL general health (p = 0.007) and SF-36 general health (p = 0.002) scores and higher WOMAC pain (p = 0.003) and global (p = 0.009) scores than patients who did not fracture. CONCLUSIONS: In acromegaly, VFs may be associated with spine deformities and sagittal imbalance, spine arthropathy, impaired QoL, and disability.

Microsurgical versus endoscopic trans-sphenoidal approaches for clivus chordoma: a pooled and meta-analysis.

Chordoma is a rare slow-growing neoplastic bone lesion. However, they show an invasive local growth and high recurrence rate, leading to an overall survival rate of 65% at 5 years and 35% at 10 years. We conducted a pooled and meta-analysis comparing recurrence rate, post-operative-complications, and survival in patients undergoing either microsurgical (MA) or endoscopic approaches (EA). Search of literature was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify surgical series of clivus chordomas published between January 1990 and March 2018 on Pubmed, Scopus, and Cochrane. Two different statistical analyses have been performed: a pooled analysis and a single-arm meta-analysis of overall recurrence rate and subgroup meta-analysis of complications in the subgroups open surgery and endoscopic surgery. After full-text screening, a total of 58 articles were included in the pooled analysis and 27 studies were included for the study-level meta-analysis. Pooled analysis-the extent of resection was the only association that remained significant (subtotal: HR = 2.18, p = 0.004; partial: HR = 4.40, p < 0.001). Recurrence was more prevalent among the surgical patients (45.5%) compared to endoscopic ones (23.7%). Meta-analysis-results of the cumulative meta-analysis showed an overall rate of recurrence of 25.6%. MA recurrence rate was 31.8% (99% CI 14-52.8), EA recurrence rate was 19.4% (5.4-39.2). CSF leak rate for the endoscopic group was 10.3% (99%CI 5-17.3) and 9.5% (99%CI 1.2-24.6) for the open surgery group. The partial removal versus total removal has an influence on recurrence rate (p < 0.001). MA recurrence rate was 31.8%; EA recurrence rate was 19.4%. The extent of resection is confirmed as a statistically significant factor affecting the risk for recurrence both with the pooled analysis and with the meta-analysis. Meta-analysis demonstrated that older patients tend to recur more than young patients, especially in surgical group.

Treatment of patients with glioma during the COVID-19 pandemic: what we learned and what we take home for the future.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) has changed the way in which cancer is treated. Patients with high-grade glioma (HGG) are believed to be in a vulnerable category. The aim of this study was to describe the experience of a hub cancer center and the measures that were put in place for treatment of patients with newly diagnosed and recurrent glioma. METHODS: To prevent in-hospital contagion and preserve the safety of health professionals and patients, specific protocols and strict regulations were introduced. Physical distancing, use of surgical masks, and diligent hand hygiene were adopted. Each case was discussed in a multidisciplinary board meeting before treatment. All patient candidates for surgical procedures were tested for SARS-CoV-2 with a nasopharyngeal swab and a chest CT scan. Indications for surgery were the radiological suspicion of HGG in patients with a good performance status and/or the rapid and progressive occurrence of neurological deficits. Adjuvant treatments were performed only in cases of HGG. This therapy consisted of conventional fractional radiotherapy (RT; 60 Gy/30 fractions) with concomitant and adjuvant temozolomide chemotherapy (TMZCHT) in younger patients; in elderly patients, a short course of RT was employed (40.5 Gy/15 fractions). For recurrent HGG, treatments were assessed after a careful evaluation of the patient's general condition, neurological status, and risk of early impairment in neurological status if not treated. During simulation CT for the RT plan, each patient underwent a chest CT study. In cases in which an imaging study was suspicious for COVID-19 pneumonia, the patient was immediately isolated and rapidly underwent nasopharyngeal swab testing. RESULTS: Between March 1 and April 30, 2020, 23 HGGs were treated, and these cases are included in the present evaluation. Fifteen patients harboring newly diagnosed glioblastoma (GBM) underwent resection followed by a regimen of chemotherapy and RT, and 3 patients with newly diagnosed anaplastic oligodendroglioma underwent surgery followed by adjuvant RT. Five patients were treated for recurrent GBM, and they received surgery plus adjuvant RT. One patient in whom the simulation CT study was suspicious for COVID pneumonia was tested with a nasopharyngeal swab, which proved positive for SARS-CoV-2 infection. No patients contracted COVID-19 during hospitalization for surgery or during RT treatment. Corticosteroid therapy was administered to all patients beginning on the 1st day of RT. CONCLUSIONS: The authors' experience during the COVID-19 pandemic showed that patients with HGG can be treated in the most effective manner without a compromise in safety. Careful selection criteria and a multidisciplinary evaluation are pivotal to assessing the optimal therapeutic strategy.

Neurosurgical digital teaching in low-middle income countries: beyond the frontiers of traditional education.

OBJECTIVE: Neurosurgical training is usually based on traditional sources of education, such as papers, books, direct surgical experience, and cadaveric hands-on courses. In low-middle income countries, standard education programs are often unavailable, mainly owing to the lack of human and economic resources. Introducing digital platforms in these settings could be an alternative solution for bridging the gap between Western and poor countries in neurosurgical knowledge. METHODS: The authors identified from the Internet the main digital platforms that could easily be adopted in low-middle income countries. They selected free/low-cost mobile content with high educational impact. RESULTS: The platforms that were identified as fulfilling the characteristics described above are WFNS Young Neurosurgeons Forum Stream, Brainbook, NeuroMind, UpSurgeOn, The Neurosurgical Atlas, Touch surgery, The 100 UCLA Subjects in Neurosurgery, Neurosurgery Survival Guide, EANS (European Association of Neurosurgical Societies) Academy, Neurosurgical.TV, 3D Neuroanatomy, The Rhoton Collection, and Hinari. These platforms consist of webinars, 3D interactive neuroanatomy and neurosurgery content, videos, and e-learning programs supported by neurosurgical associations or journals. CONCLUSIONS: Digital education is an emerging tool for contributing to the spread of information in the neurosurgical community. The continuous improvement in the quality of content will rapidly increase the scientific validity of digital programs. In conclusion, the fast and easy access to digital resources could contribute to promote neurosurgical education in countries with limited facilities.

Hypofractionated stereotactic radiation therapy in skull base meningiomas.

To investigate the role of hypo-fractionated stereotactic radiation treatment (HSRT) in the management of skull base meningioma. Twenty-six patients were included in the study and treated with a dose of 30 Gy in 5 fractions with volumetric modulated arc therapy (RapidArc). Eighteen patients were symptomatic before treatment. Endpoints were local toxicity and relief from symptoms. Tumors were located in anterior skull base in 4/27 cases, in middle skull base in 12/27 and in posterior skull base in 11/27. HSRT was performed as first treatment in 17 (65 %) patients, in 9 (35 %) patients it followed a previous partial resection. Median follow up was 24.5 months (range 5-57 months). clinical remission of symptoms, complete or partial, was obtained in the vast majority of patients after treatment. Out of the 18 symptomatic patients, partial remission occurred in 9 (50 %) patients and complete remission in 9 (50 %). All asymptomatic patients retained their status after treatment. No severe neurologic toxicity grade III-IV was recorded. No increase of meningioma in the same site of treatment occurred; 16 (62 %) patients had stable disease and 9 (38 %) patients had tumor reduction. The mean tumor volume after treatment was 10.8 ± 17.8 cm(3) compared with 13.0 ± 19.1 cm(3) before treatment (p = 0.02). The mean actuarial OS was 54.4 ± 2.8 months. The 1- and 2-years OS was 92.9 ± 0.7 %. HSRT proved to be feasible for these patients not eligible to full surgery or to ablative radiation therapy. Local control and durability of results suggest for a routine application of this approach in properly selected cases.

Predictive Factors of Long-Term Neurologic Outcome and Progression-Free Survival in Intramedullary Spinal Cord Tumors: A 10-year Single-Center Cohort Study and Review of the Literature.

BACKGROUND: Intramedullary spinal cord tumors (IMSCTs) are a rare subgroup of neoplasms, encompassing both benign, slow-growing masses, and malignant lesions; radical surgical excision represents the cornerstone of treatment for such pathologies regardless of histopathology, which, on the other hand, is a known predictor of survival and neurologic outcome postsurgery. The present study aims to investigate the relevance of other factors in predicting survival and long-term functional outcomes. METHODS: We conducted a review of current literature on functional outcomes of IMSCTs, as well as a 10-years prospective analysis of a wide cohort of patients with diagnosis of IMSCTs who underwent surgical resection at our institution. RESULTS: Our series encompasses 60 patients with IMSCTS, among which 36 ependymomas, 6 cavernous angiomas, 5 hemangioblastomas, 6 WHO Grade I-IV astrocytomas, 3 intramedullary spinal metastases and 4 miscellaneous tumors. GTR was achieved in 76,67% of patients, with high preoperative McCormick grade, syringomyelia and changes at neurophysiologic monitoring being the strongest predictors at multivariate analysis (P = 0.0027, P = 0.0017 and P = 0.001 respectively). CONCLUSIONS: Consistently with literature, preoperative neurologic function is the most important factor predicting long-term functional outcome (0.17, CI 0.069-0.57 with P = 0.0018), advocating for early surgery in the management of IMSCTs, whereas late complications such as myelopathy and neuropathic pain were present regardless of preoperative function.

Proposal of a new score system (Cervical Surgical Score) for management of degenerative cervical myelopathy.

BACKGROUND: To date, no shared algorithms with the aim of guiding surgical strategy in complex cases of degenerative cervical myelopathy (DCM) exist. Our purpose is to present the Cervical Surgical Score (CSS) which could help in identifying complex DCM cases, suggesting a surgical strategy. METHODS: We created the CSS based on multidisciplinary and literature-focused discussions, based on eight parameters including number of levels of cervical pathology and myelopathy, type and predominance of compression and grade of clinical myelopathy. We prospectively enrolled surgical DCM patients in a 15-months period, collecting clinical and radiological data. During outpatient clinic a specific surgical indication was offered to DCM patients. To validate the score, each outpatient clinic surgical indication was compared a posteriori to the one that resulted from multidisciplinary CSS scoring, focusing on patients for which both an anterior and posterior approach were considered suitable. RESULTS: A total of 100 patients operated on for DCM at our Institution between December 2021 and February 2023 were prospectively enrolled. In 53% of patients the pathology was present at more than two levels. According to CSS calculation, 14% of patients resulted in the "grey zone", where both an anterior and posterior approach were deemed feasible. Among them, in 42.8% of cases the CSS allowed a modification of the originally planned surgery. Looking at outcome, an improvement of m-JOA score in 62% of patients was disclosed. CONCLUSIONS: This preliminary study showed the reliability and usefulness of CSS in detecting complex DCM cases, requiring further analysis by expert spine surgeons, suggesting a surgical strategy.

Instrumented fusion surgery in elderly patients (over 75 years old): clinical and radiological results in a series of 53 patients.

OBJECTIVE: To evaluate the clinical and radiological outcomes of elderly (>75 years old) patients who underwent spinal instrumented fusion surgery. METHODS: Patients underwent lumbar pedicle screw fixation and fusion for degenerative spondylolisthesis. Clinical and radiological outcomes were assessed. RESULTS: 53 patients were studied. Pre-operative VAS was 7.8, ODI was 47.6 %. 254 screws were placed (36 single level; 13 double levels and 4 cases three-levels). No mortality occurred. At 18 months follow-up VAS was 4.1, ODI was 21.8 %. A stable fusion was observed in 41 patients (78.8 %); in four cases there was minimal sign of instability and seven patients underwent a second surgery due to screw mobilization. CONCLUSION: Spinal fixation and fusion in patients older than 75 years old grants good results in terms of quality of life but the rate of morbidity is higher than standard spine surgery. Rate of fusion especially is still a critical point.

Single-Stage Posterior Transpedicular Corpectomy and 360-Degree Reconstruction for Thoracic and Lumbar Burst Fractures: Technical Nuances and Outcomes.

BACKGROUND: We evaluate the feasibility of a single-stage posterior corpectomy and circumferential arthrodesis with the aid of spinal navigation for the treatment of traumatic thoracolumbar burst fractures. METHODS: This was a single-center, retrospective study. Demographics, clinical, and radiologic data of 19 patients who underwent surgery at our institution for thoracolumbar burst fractures between 2016 and 2019 were collected. All patients enrolled in the present study underwent surgery by means of posterior fixation and transpedicular corpectomy with the aid of an intraoperative image-guided neuronavigation system. RESULTS: Postoperative correction of the vertebral height ratio was achieved in all cases, with an average increase of 23.6% (p = 0.0005). No statistical differences (p = 0.9) were found comparing 1- and 3-month postoperative CT scans, in relation to vertebral height ratio. A statistically significant difference was found between the pre- and postoperative kyphotic angles for the thoracolumbar and lumbar segments (p = 0.0018 and 0.005, respectively), but no difference was found between kyphotic angles at the 3-month follow-up. A unilateral approach was performed on 15 patients (79%), while 4 cases (21%) required a bilateral laminectomy. We did not observe any significant intraoperative complication. CONCLUSION: Single-stage posterior corpectomy and fixation is a safe and effective approach for thoracic and lumbar burst fractures. It provides excellent 360-degree reconstruction in a single surgical stage with satisfactory results in terms of kyphosis reduction, biomechanical stability, and reduced invasiveness. Spinal navigation represents a fundamental tool to overcome some anatomical limits of the presented technique.

Minimally invasive microsurgical decompression of the lumbar spine using a novel robotised digital microscope: A preliminary experience.

BACKGROUND: The operative microscope (OM) represents, to date, the standard for neurosurgical procedures. However, new technologies have been proposed during the latest years to overcome its limitations, from high-quality exoscopes to complex robotised visualisation systems. We report our preliminary experience with a novel digital robotised microscope, the BHS RoboticScope (RS), for minimally invasive spinal surgery. METHODS: We employed the RS in five consecutive patients who underwent bilateral lumbar spine decompression through a monolateral approach. Patient outcomes, device technical characteristics and the surgeon's personal perspectives have been evaluated. RESULTS: No complications occurred. All procedures were concluded without switching to the microscope. Image quality, lightning, depth perception and freedom of movement were judged satisfactory as compared to the standard microscope. CONCLUSION: The easy maneuverability and the high quality of pictures provided by the RS device improve the surgeon's comfort in deep fields, representing an effective option for minimally invasive spinal procedures.

Lumbar adjacent segment degeneration after spinal fusion surgery: a systematic review and meta-analysis.

INTRODUCTION: Adjacent segment degeneration is among the most recognized long-term complications of lumbar surgery for degenerative spine pathologies with a relevant impact in spine surgical and clinical practice. It is reported a incidence of clinical adjacent segment disease between 5-30% of patients undergoing spinal fusion. We aimed to evaluate the main clinical and surgical risk factors for developing adjacent segment disease. EVIDENCE ACQUISITION: A systematic review and meta-analysis of the pertinent literature was performed, according to PRISMA and PICO guidelines, focusing on clinical and radiological adjacent segment disease. We exclusively included studies reporting demographic and clinical data, and surgical details published from 30 September 2015 to 30 September 2020. The effect of considered risk factors on the presence of adjacent segment disease was explored with a random-effects model. EVIDENCE SYNTHESIS: A total of 15 scientific publications, corresponding to 6253 patients, met the inclusion criteria for the qualitative and quantitative analysis. 720 of the patients developed a clinical and/or radiological adjacent syndrome disease, and 473 have been surgically managed. Ten articles qualified for the comparative geographical analysis. Advanced age and obesity are relevant risk factors for developing lumbar adjacent segment degeneration. Our data also reported a higher prevalence of adjacent segment degeneration in Western populations than in Eastern populations. The interbody fusion has a protective role toward lumbar adjacent segment degeneration. CONCLUSIONS: This study highlighted multifactorial issues regarding adjacent segment disease: clinical, anatomical, biomechanical, and radiological features. In view of increasing life expectancy and spinal surgery procedures, extensive multicenter studies will be needed to define the correct management of the adjacent segment disease.

Multimodal Intraoperative Neurophysiological Monitoring in Intramedullary Spinal Cord Tumors: A 10-Year Single Center Experience.

OBJECTIVE: The study aimed at evaluating the efficacy and the ability of D-wave monitoring combined with somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) to predict functional outcomes in intramedullary spinal cord tumor (IMSCT) surgery. METHODS: Between December 2011 and December 2020, all patients harboring IMSCT who underwent surgery at our institution were prospectively collected in a surgical spinal registry and retrospectively analyzed. Patient charts and surgical and histological reports were analyzed. The multimodal IONM included SSEPs, MEPs, and-whenever possible-D-waves. All patients were evaluated using the modified McCormick and Frankel grade at admission and 3, 6, and 12 months of follow-up. RESULTS: Sixty-four patients were enrolled in the study. SSEP and MEP monitoring was performed in all patients. The D-wave was not recordable in seven patients (11%). Significant IONM changes (at least one evoked potential modality) were registered in 26 (41%) of the 64 patients. In five cases (8%) where the SSEPs and MEPs lost and the D-wave permanently dropped by about 50%, patients experienced a permanent deterioration of their neurological status. Multimodal IONM (SSEP, MEP, and D-wave neuromonitoring) significantly predicted postoperative deficits (p = 0.0001), with a sensitivity of 100.00% and a specificity of 95.65%. However, D-waves demonstrated significantly higher sensitivity (100%) than MEPs (62.5%) and SSEPs (71.42%) alone. These tests' specificities were 85.10%, 13.89%, and 17.39%, respectively. Comparing the area under ROC curves (AUCs) of these evoked potentials in 53 patients (where all three modalities of IONM were registered) using the pairwise t-test, D-wave monitoring appeared to have higher accuracy and ability to predict postoperative deficits with strong statistical significance compared with MEP and SSEP alone (0.992 vs. 0.798 vs. 0.542; p = 0.018 and p < 0.001). CONCLUSION: The use of multimodal IONM showed a statistically significant greater ability to predict postoperative deficits compared with SSEP, MEP, and D-wave monitoring alone. D-wave recording significantly increased the accuracy and clinical value of neurophysiological monitoring in IMSCT tumor resection.

The lumbar adjacent-level syndrome: analysis of clinical, radiological, and surgical parameters in a large single-center series.

OBJECTIVE: The development of specific clinical and neurological symptoms and radiological degeneration affecting the segment adjacent to a spinal arthrodesis comprise the framework of adjacent-level syndrome. Through the analysis of a large surgical series, this study aimed to identify possible demographic, clinical, radiological, and surgical risk factors involved in the development of adjacent-level syndrome. METHODS: A single-center retrospective analysis of adult patients undergoing lumbar fusion procedures between January 2014 and December 2018 was performed. Clinical, demographic, radiological, and surgical data were collected. Patients who underwent surgery for adjacent-segment disease (ASD) were classified as the ASD group. All patients were evaluated 1 month after the surgical procedure clinically and radiologically (with lumbar radiographs) and 3 months afterward with CT scans. The last follow-up was performed by telephone interview. The median follow-up for patients included in the analysis was 67.2 months (range 39-98 months). RESULTS: A total of 902 patients were included in this study. Forty-nine (5.4%) patients required reoperation for ASD. A significantly higher BMI value was observed in the ASD group (p < 0.001). Microdiscectomy and microdecompression procedures performed at the upper or lower level of an arthrodesis without fusion extension have a statistically significant impact on the development of ASD (p = 0.001). Postoperative pelvic tilt in the ASD group was higher than in the non-ASD group. Numeric rating scale, Core Outcome Measures Index, and Oswestry Disability Index scores at the last follow-up were significantly higher in patients in the ASD group and in patients younger than 65 years. CONCLUSIONS: Identifying risk factors for the development of adjacent-level syndrome allows the implementation of a prevention strategy in patients undergoing lumbar arthrodesis surgery. Age older than 65 years, high BMI, preexisting disc degeneration at the adjacent level, and high postoperative pelvic tilt are the most relevant factors. In addition, patients older than 65 years achieve higher levels of clinical improvement and postsurgical satisfaction than do younger patients.

Towards a common language in neurosurgical outcome evaluation: the NEON (NEurosurgical Outcome Network) proposal.

BACKGROUND: The aim of this study was to achieve a consensus on the minimum set of outcome measures and predictors to be used in the neurosurgical practice and on the timing of outcome assessment. METHODS: A consensus building approach was employed. All neurosurgical departments in Lombardy (Italy) were invited to participate by the Carlo Besta Neurologic Institute IRCCS Foundation. Three workshops were organized during which a multidisciplinary group called Neurosurgical Outcome Network (NEON) was created and the methodology to select outcome measures, predictors, and timing of outcome assessment was established. Eight working groups were created for the different neurosurgical diseases (neuro-oncological, skull base, vascular, traumatic, spinal, peripheral nervous system, malformation, functional) and 8 workshops were organized to identify the outcome measures and predictors specific for each of the neurosurgical diseases based on the experts' clinical practice and the existing literature. RESULTS: A total of 20 neurosurgical departments participated in this study. Specific outcome measures, predictors and the timing of outcome assessment were identified for each of the 8 neurosurgical diseases. Moreover, a list of variables common to all pathologies were identified by the NEON group as further data to be collected. CONCLUSIONS: A consensus on the minimum set of outcome measures and predictors and the timing of outcome assessments for 8 neurosurgical diseases was achieved by a group of neurosurgeons of the Lombardy region, called NEON. These sets could be used in future studies for a more homogeneous data collection and as a starting point to reach further agreement also at national and international level.

Evaluation of the rate of decompression in anterior cervical corpectomy using an intra-operative computerized tomography scan (O-Arm system).

OBJECT: The purpose of this study was to evaluate the efficacy of intra-operative computerized tomography (CT) scanning in the analysis of bone removal accuracy during anterior cervical corpectomy, in order to allow any necessary immediate correction in the event of inadequate bone removal. METHODS: From September 2009 to December 2010 we performed an intra-operative (CT) scan using the O-Arm(™) Image system to assess the rate of central and lateral decompression in all patients treated for cervical spondylotic myelopathy by anterior cervical corpectomy and fusion. RESULTS: Out of a population of 187 patients admitted to our department, with a diagnosis of myelopathy due to spondylotic degenerative cervical stenosis, 15 patients underwent a surgical treatment with anterior cervical corpectomy and fusion. There were nine males (60%) and six females (40%); the mean age was 52.4 years, ranging from 41 to 57 years. The pre-operative radiologic investigations (MRI and CT scans) revealed in the nine patients (60%) the extent of the compression to one vertebral body (C4 one case, C5 four cases, C6 four cases), while in the six cases (40%) the compression regarded two vertebral body (C3 and C4 one case, C4 and C5 two cases, C5 and C6 three cases). During surgery, when the decompression was judged completely, a CT scan was performed: in 11 cases (73.3%) the decompression was considered adequate, while in four cases (26.7%) it was deemed insufficient and the surgical strategy was changed in order to optimize the bone removal. In these cases an additional scan was taken to prove the efficacy of decompression, achieved in all patients. CONCLUSION: Intra-operative CT scan performed during cervical corpectomy is a really useful tool in helping to ensure complete bone removal and the adequacy of surgery. The O-arm(™) Image system grants optimal image quality, allowing correctly assessing the rate of decompression and, in any case of doubt, allows an intra-operative evaluation of the final correct positioning of the graft.

Epidemiology, natural course, and preventive measures of osteoporotic vertebral fractures: WFNS Spine Committee Recommendations.

INTRODUCTION: This review aims to search for up-to-date information on epidemiology, natural course, and preventive measures of osteoporotic spine fractures. EVIDENCE ACQUISITION: We reviewed the literature of the last ten years using keywords "natural course and osteoporotic vertebral fractures," "epidemiology and osteoporotic vertebral fractures" and "prevention and osteoporotic vertebral fractures." We then discussed the search results to reach an agreement in two consensus meetings on January and February 2021 of the World Federation of Neurosurgical Societies (WFNS) Spine Committee. Finally, we utilized the Delphi method to administer the questionnaire to preserve a high degree of validity. We summarized seven papers on the natural course, 15 articles on epidemiology, and 84 papers on preventing osteoporotic vertebral fractures. Finally, the consensus results after voting are presented. EVIDENCE SYNTHESIS: Natural course of acute osteoporotic vertebral fractures is benign; many patients may have sufficient pain relief during the first three months with conservative treatment. At the end of one year of conservative treatment, 40% may still have pain with VAS-scores ≥4. Since the populations are aging, the incidence of OVF continues to rise. Although the prevalence varies across the globe, the highest rates are from North America and some countries of Asia. Preventive treatment of OVF must involve an active lifestyle, adequate nutrition, prevention of immobilization with physical therapy, and pharmacological therapy. Oral calcium and vitamin D are first-line interventions to prevent the bone mass loss, especially in postmenopausal women. There are many pharmacological treatment options; the decision must be made by fracture risk assessment (clinical factors + BMD + BMI) alone or along with DXA (dual-energy X-ray absorptiometry) or history of previous fragility fractures. The indication of one respect to the others is based on patient preference, compliance, and risk of discontinuation related to adverse events and administration method. CONCLUSIONS: The incidence of osteoporotic vertebral fractures increases with age and other factors. The natural course shows that most patients benefit from conservative therapy without any surgical intervention during the first three months. Preventive measures must include active lifestyle, adequate nutrition, prevention of immobilization with physical therapy, oral calcium, and vitamin D intake, and pharmacological therapy after fracture risk assessment.