The international spine registry SPINE TANGO: status quo and first results

With an official life time of over 5years, Spine Tango can meanwhile be considered the first international spine registry. In this paper we present an overview of frequency statistics of Spine Tango for demonstrating the genesis of questionnaire development and the constantly increasing activity in the registry. Results from two exemplar studies serve for showing concepts of data analysis applied to a spine registry. Between 2002 and 2006, about 6,000 datasets were submitted by 25 centres. Descriptive analyses were performed for demographic, surgical and follow-up data of three generations of the Spine Tango surgery and follow-up forms. The two exemplar studies used multiple linear regression models to identify potential predictor variables for the occurrence of dura lesions in posterior spinal fusion, and to evaluate which covariates influenced the length of hospital stay. Over the study period there was a rise in median patient age from 52.3 to 58.6years in the Spine Tango data pool and an increasing percentage of degenerative diseases as main pathology from 59.9 to 71.4%. Posterior decompression was the most frequent surgical measure. About one-third of all patients had documented follow-ups. The complication rate remained below 10%. The exemplar studies identified "centre of intervention” and "number of segments of fusion” as predictors of the occurrence of dura lesions in posterior spinal fusion surgery. Length of hospital stay among patients with posterior fusion was significantly influenced by "centre of intervention”, "surgeon credentials”, "number of segments of fusion”, "age group” and "sex”. Data analysis from Spine Tango is possible but complicated by the incompatibility of questionnaire generations 1 and 2 with the more recent generation 3. Although descriptive and also analytic studies at evidence level 2++ can be performed, findings cannot yet be generalised to any specific country or patient population. Current limitations of Spine Tango include the low number and short duration of follow-ups and the lack of sufficiently detailed patient data on subgroup levels. Although the number of participants is steadily growing, no country is yet represented with a sufficient number of hospitals. Nevertheless, the benefits of the project for the whole spine community become increasingly visibl

The diagnostic value of a treadmill test in predicting lumbar spinal stenosis

Lumbar spinal stenosis is a frequent indication for spinal surgery. The predictive quality of treadmill testing and MRI for diagnostic verification is not yet clearly defined. Aim of the current study was to assess correlations between treadmill testing and MRI findings in the lumbar spine. Twenty-five patients with lumbar spinal stenosis were prospectively examined. Treadmill tests were performed and the area of the dural sac and neuroforamina was examined with MRI for the narrowest spinal segment. VAS and ODI were used for clinical assessment. The median age of the patients was 67years. In the narrowest spinal segment the median area of the dural sac was 91mm2. The median ODI was 66 per cent. The median walking distance in the treadmill test was 70m. The distance reached in the treadmill test correlated with the area of the dural sac (Spearman's ρ=0.53) and ODI (ρ=−0.51), but not with the area of the neuroforamina and VAS. The distance reached in the treadmill test predicts the grade of stenosis in MRI but has a limited diagnostic importance for the level of clinical symptoms in lumbar spinal stenosi

Letter to the editor concerning ‘‘Relationship between sedimentation sign and morphological grade in symptomatic lumbar spinal stenosis’’ (by Laudato PA, Kulik G, Schizas C (2015) Eur Spine J; 24(10):2264–2268)

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch

Robust Tumor Segmentation with Hyperspectral Imaging and Graph Neural Networks

Segmenting the boundary between tumor and healthy tissue during surgical cancer resection poses a significant challenge. In recent years, Hyperspectral Imaging (HSI) combined with Machine Learning (ML) has emerged as a promising solution. However, due to the extensive information contained within the spectral domain, most ML approaches primarily classify individual HSI (super-)pixels, or tiles, without taking into account their spatial context. In this paper, we propose an improved methodology that leverages the spatial context of tiles for more robust and smoother segmentation. To address the irregular shapes of tiles, we utilize Graph Neural Networks (GNNs) to propagate context information across neighboring regions. The features for each tile within the graph are extracted using a Convolutional Neural Network (CNN), which is trained simultaneously with the subsequent GNN. Moreover, we incorporate local image quality metrics into the loss function to enhance the training procedure's robustness against low-quality regions in the training images. We demonstrate the superiority of our proposed method using a clinical ex vivo dataset consisting of 51 HSI images from 30 patients. Despite the limited dataset, the GNN-based model significantly outperforms context-agnostic approaches, accurately distinguishing between healthy and tumor tissues, even in images from previously unseen patients. Furthermore, we show that our carefully designed loss function, accounting for local image quality, results in additional improvements. Our findings demonstrate that context-aware GNN algorithms can robustly find tumor demarcations on HSI images, ultimately contributing to better surgery success and patient outcome.Comment: 11 pages, 6 figure

Increased intraoperative epidural pressure in lumbar spinal stenosis patients with a positive nerve root sedimentation sign

Purpose: The sedimentation sign (SedSign) has been shown to discriminate well between selected patients with and without lumbar spinal stenosis (LSS). The purpose of this study was to compare the pressure values associated with LSS versus non-LSS and discuss whether a positive SedSign may be related to increased epidural pressure at the level of the stenosis. Methods: We measured the intraoperative epidural pressure in five patients without LSS and a negative SedSign, and in five patients with LSS and a positive SedSign using a Codman™ catheter in prone position under radioscopy. Results: Patients with a negative SedSign had a median epidural pressure of 9mmHg independent of the measurement location. Breath and pulse-synchronous waves accounted for 1-3mmHg. In patients with monosegmental LSS and a positive SedSign, the epidural pressure above and below the stenosis was similar (median 8-9mmHg). At the level of the stenosis the median epidural pressure was 22mmHg. A breath and pulse-synchronous wave was present cranial to the stenosis, but absent below. These findings were independent of the cross-sectional area of the spinal canal at the level of the stenosis. Conclusions: Patients with LSS have an increased epidural pressure at the level of the stenosis and altered pressure wave characteristics below. We argue that the absence of sedimentation of lumbar nerve roots to the dorsal part of the dural sac in supine position may be due to tethering of affected nerve roots at the level of the stenosis

Getting It on Record: Issues and Strategies for Ethnographic Practice in Recording Studios

The recording studio has been somewhat neglected as a site for ethnographic fieldwork in the field of ethno-musicology and, moreover, the majority of published studies tend to overlook the specific concerns faced by the researcher within these contexts. Music recording studios can be places of creativity, artistry, and collaboration, but they often also involve challenging, intimidating, and fractious relations. Given that recording studios are, first and foremost, concerned with documenting musicians’ performances, we discuss the concerns of getting studio interactions “on record” in terms of access, social relations, and methods of data collection. This article reflects on some of the issues we faced when conducting our fieldwork within British music recording facilities and makes suggestions based on strategies that we employed to address these issues

The glioblastoma multiforme tumor site promotes the commitment of tumor-infiltrating lymphocytes to the TH17 lineage in humans

Although glioblastoma multiforme (GBM) is not an invariably cold tumor, checkpoint inhibition has largely failed in GBM. In order to investigate T cell-intrinsic properties that contribute to the resistance of GBM to endogenous or therapeutically enhanced adaptive immune responses, we sorted CD4(+) and CD8(+) T cells from the peripheral blood, normal-appearing brain tissue, and tumor bed of nine treatment-naive patients with GBM. Bulk RNA sequencing of highly pure T cell populations from these different compartments was used to obtain deep transcriptomes of tumor-infiltrating T cells (TILs). While the transcriptome of CD8(+) TILs suggested that they were partly locked in a dysfunctional state, CD4(+) TILs showed a robust commitment to the type 17 T helper cell (T(H)17) lineage, which was corroborated by flow cytometry in four additional GBM cases. Therefore, our study illustrates that the brain tumor environment in GBM might instruct T(H)17 commitment of infiltrating T helper cells. Whether these properties of CD4(+) TILs facilitate a tumor-promoting milieu and thus could be a target for adjuvant anti-T(H)17 cell interventions needs to be further investigated

Age-adjusted Charlson comorbidity index in recurrent glioblastoma: a new prognostic factor?

BACKGROUND: For recurrent glioblastoma (GB) patients, several therapy options have been established over the last years such as more aggressive surgery, re-irradiation or chemotherapy. Age and the Karnofsky Performance Status Scale (KPSS) are used to make decisions for these patients as these are established as prognostic factors in the initial diagnosis of GB. This study’s aim was to evaluate preoperative patient comorbidities by using the age-adjusted Charlson Comorbidity Index (ACCI) as a prognostic factor for recurrent GB patients. METHODS: In this retrospective analysis we could include 123 patients with surgery for primary recurrence of GB from January 2007 until December 2016 (43 females, 80 males, mean age 57 years (range 21–80 years)). Preoperative age, sex, ACCI, KPSS and adjuvant treatment regimes were recorded for each patient. Extent of resection (EOR) was recorded as a complete/incomplete resection of the contrast-enhancing tumor part. RESULTS: Median overall survival (OS) was 9.0 months (95% CI 7.1–10.9 months) after first re-resection. Preoperative KPSS > 80% (P < 0.001) and EOR (P = 0.013) were associated with significantly improved survival in univariate analysis. Including these factors in multivariate analysis, preoperative KPSS < 80 (HR 2.002 [95% CI: 1.246–3.216], P = 0.004) and EOR are the only significant prognostic factor (HR 1.611 [95% CI: 1.036–2.505], P = 0.034). ACCI was not shown as a prognostic factor in univariate and multivariate analyses. CONCLUSION: For patients with surgery for recurrent glioblastoma, the ACCI does not add further information about patient’s prognosis besides the well-established KPSS and extent of resection

Safe Brain Tumor Resection Does not Depend on Surgery Alone - Role of Hemodynamics

Aim of this study was to determine if perioperative hemodynamics have an impact on perioperative infarct volume and patients' prognosis. 201 cases with surgery for a newly diagnosed or recurrent glioblastoma were retrospectively analyzed. Clinical data and perioperative hemodynamic parameters, blood tests and time of surgery were recorded. Postoperative infarct volume was quantitatively assessed by semiautomatic segmentation. Mean diastolic blood pressure (dBP) during surgery (rho -0.239, 95% CI -0.11 - -0.367, p = 0.017), liquid balance (rho 0.236, 95% CI 0.1-0.373, p = 0.017) and mean arterial pressure (MAP) during surgery (rho -0.206, 95% CI -0.07 - -0.34, p = 0.041) showed significant correlation to infarct volume. A rank regression model including also age and recurrent surgery as possible confounders revealed mean intraoperative dBP, liquid balance and length of surgery as independent factors for infarct volume. Univariate survival analysis showed mean intraoperative dBP and MAP as significant prognostic factors, length of surgery also remained as significant prognostic factor in a multivariate model. Perioperative close anesthesiologic monitoring of blood pressure and liquid balance is of high significance during brain tumor surgery and should be performed to prevent or minimize perioperative infarctions and to prolong survival