Abstract: Background Minimally invasive intracranial drain placement is a common neurosurgical emergency procedure in patients with intracerebral hemorrhage (ICH). We aimed to retrospectively investigate the accuracy of conventional freehand (bedside) hemorrhage drain placement and to prospectively compare the accuracy of augmented/mixed reality-guided (AR) versus frame-based stereotaxy-guided (STX) and freehand drain placement in a phantom model. Methods A retrospective, single-center analysis evaluated the accuracy of drain placement in 73 consecutive ICH with a visual rating of postinterventional CT data. In a head phantom with a simulated deep ICH, five neurosurgeons performed four punctures for each technique: STX, AR, and the freehand technique. The Euclidean distance to the target point and the lateral deviation of the achieved trajectory from the planned trajectory at target point level were compared between the three methods. Results Analysis of the clinical cases revealed an optimal drainage position in only 46/73 (63%). Correction of the drain was necessary in 23/73 cases (32%). In the phantom study, accuracy of AR was significantly higher than the freehand method (P0.001 for both Euclidean and lateral distances). The Euclidean distance using AR (median 3 mm) was close to that using STX (median 1.95 mm; P=0.023).br

Abstract: BACKGROUND Neuraxial access is necessary for an array of procedures in anaesthesia, interventional pain medicine and neurosurgery. The commonly used anatomical landmark technique is challenging and requires practical experience. OBJECTIVE We aimed to evaluate the technical feasibility of an augmented reality-guided approach for neuraxial access and tested the hypothesis that its use would improve success as the primary outcome. As secondary outcomes, we measured accuracy and the procedural duration compared with the classical landmark approach. DESIGN A randomised phantom-based study. SETTING The three-dimensional image of a thoracolumbar phantom spine model with the surrounding soft tissue was created with a neurosurgical planning workstation and ideal trajectories to the epidural space on the levels T10-L1 were planned using a paramedian approach. Both the three-dimensional holographic image of the spine and the trajectories were transferred to an augmented reality-headset. Four probands (two anaesthesiologists, one neuroradiologist and one stereotactic neurosurgeon) performed 20 attempts, 10 each of either conventional landmark or augmented reality-guided epidural punctures, where anatomical level, side and sequence of modality were all randomised. OUTCOME MEASURES Accuracy was assessed by measuring Euclidean distance and lateral deviation from the predefined target point. Success of epidural puncture on the first attempt was compared between the conventional and the augmented reality-guided approaches. RESULTS Success was achieved in 82.5% of the attempts using augmented reality technique, compared with 40% with the conventional approach [P = 0.0002, odds ratio (OR) for success: 7.07]. Euclidean distance (6.1 vs. 12 mm, P 0.0001) and lateral deviation (3.7 vs. 9.2 mm, P 0.0001) were significantly smaller using augmented reality. Augmented reality-guided puncture was significantly faster than with the conventional landmark approach (52.5 vs. 67.5 s, P = 0.0015).br

Abstract: Purpose To assess whether high temporal/spatial resolution GRASP MRI acquired during routine clinical imaging can identify several degrees of renal function impairment referenced against renal dynamic scintigraphy. Methods This retrospective study consists of method development and method verification parts. During method development, patients subject to renal imaging using gadoterate meglumine and GRASP post-contrast MRI technique (TR/TE 3.3/1.6 ms; FoV320 × 320 mm; FA12°; Voxel1.1 × 1.1x2.5 mm) were matched into four equally-sized renal function groups (no-mild-moderate-severe impairment) according to their laboratory-determined estimated glomerular filtration rates (eGFR); 60|120 patients|kidneys were included. Regions-of-interest (ROIs) were placed on cortices, medullary pyramids and collecting systems of bilateral kidneys. Cortical perfusion, tubular concentration and collecting system excretion were determined as TimeCortex=Pyramid(sec), SlopeTubuli (sec−1), and TimeCollecting System (sec), respectively, and were measured by a combination of extraction of time intensity curves and respective quantitative parameters. For method verification, patients subject to GRASP MRI and renal dynamic scintigraphy (99mTc-MAG3, 100 MBq/patient) were matched into three renal function groups (no-mild/moderate-severe impairment). Split renal function parameters post 1.5-2.5 min as well as MAG3 TER were correlated with time intensity parameters retrieved using GRASP technique; 15|30 patients|kidneys were included. Results Method development showed differing values for TimeCortex=Pyramid(71|75|93|122 s), SlopeTubuli(2.6|2.1|1.3|0.5 s−1) and TimeCollecting System(90|111|129|139 s) for the four renal function groups with partial significant tendencies (several p-values 0.001). In method verification, 29/30 kidneys (96.7%) were assigned to the correct renal function group.brbrConclusion

Abstract: Background and purpose: The role of surgery in the treatment of intracerebral haemorrhage (ICH) remains controversial. Whereas open surgery has failed to show any clinical benefit, recent studies have suggested that minimal invasive procedures can indeed be beneficial, especially when they are applied at an early time point. This retrospective study therefore evaluated the feasibility of a free-hand bedside catheter technique with subsequent local lysis for early haematoma evacuation in patients with spontaneous supratentorial ICH. Methods: Patients with spontaneous supratentorial haemorrhage of a volume of >30 mL who were treated with bedside catheter haematoma evacuation were identified from our institutional database. The entry point and evacuation trajectory of the catheter were based on a 3D-reconstructed CT scan. The catheter was inserted bedside into the core of the haematoma, and urokinase (5,000 IE) was administered every 6 h for a maximum of 4 days. Evolution of haematoma volume, perihaemorrhagic edema, midline-shift, adverse events and functional outcome were analyzed. Results: A total of 110 patients with a median initial haematoma volume of 60.6 mL were analyzed. Haematoma volume decreased to 46.1 mL immediately after catheter placement and initial aspiration (with a median time to treatment of 9 h after ictus), and to 21.0 mL at the end of urokinase treatment. Perihaemorrhagic edema decreased significantly from 45.0 mL to 38.9 mL and midline-shift from 6.0 mm to 2.0 mm. The median NIHSS score improved from 18 on admission to 10 at discharge, and the median mRS at discharge was 4; the latter was even lower in patients who reached a target volume ≤ 15 mL at the end of local lysis. The in-hospital mortality rate was 8.2%, and catheter/local lysis-associated complications occurred in 5.5% of patients. Conclusion: Bedside catheter aspiration with subsequent urokinase irrigation is a safe and feasible procedure for treating spontaneous supratentorial ICH, and can immediately reduce the mass effects of haemorrhage. Additional controlled studies that assess the long-term outcome and generalizability of our findings are therefore warranted. Clinical trial registration: [www.drks.de], identifier [DRKS00007908]

Abstract: n the past, changes of the Apparent Diffusion Coefficient in glioblastoma multiforme have been shown to be related to specific genes and described as being associated with survival. The purpose of this study was to investigate diffusion imaging parameters in combination with genome-wide expression data in order to obtain a comprehensive characterisation of the transcriptomic changes indicated by diffusion imaging parameters. Diffusion-weighted imaging, molecular and clinical data were collected prospectively in 21 patients. Before surgery, MRI diffusion metrics such as axial (AD), radial (RD), mean diffusivity (MD) and fractional anisotropy (FA) were assessed from the contrast enhancing tumour regions. Intraoperatively, tissue was sampled from the same areas using neuronavigation. Transcriptional data of the tissue samples was analysed by Weighted Gene Co-Expression Network Analysis (WGCNA) thus classifying genes into modules based on their network-based affiliations. Subsequent Gene Set Enrichment Analysis (GSEA) identified biological functions or pathways of the expression modules. Network analysis showed a strong association between FA and epithelial-to-mesenchymal-transition (EMT) pathway activation. Also, patients with high FA had a worse clinical outcome. MD correlated with neural function related genes and patients with high MD values had longer overall survival. In conclusion, FA and MD are associated with distinct molecular patterns and opposed clinical outcomes

Abstract: Although the free water content within the perilesional T2 hyperintense region should differ between glioblastomas (GBM) and brain metastases based on histological differences, the application of classical MR diffusion models has led to inconsistent results regarding the differentiation between these two entities. Whereas diffusion tensor imaging (DTI) considers the voxel as a single compartment, multicompartment approaches such as neurite orientation dispersion and density imaging (NODDI) or the recently introduced diffusion microstructure imaging (DMI) allow for the calculation of the relative proportions of intra- and extra-axonal and also free water compartments in brain tissue. We investigate the potential of water-sensitive DTI, NODDI and DMI metrics to detect differences in free water content of the perilesional T2 hyperintense area between histopathologically confirmed GBM and brain metastases. Respective diffusion metrics most susceptible to alterations in the free water content (MD, V-ISO, V-CSF) were extracted from T2 hyperintense perilesional areas, normalized and compared in 24 patients with GBM and 25 with brain metastases. DTI MD was significantly increased in metastases (p = 0.006) compared to GBM, which was corroborated by an increased DMI V-CSF (p = 0.001), while the NODDI-derived ISO-VF showed only trend level increase in metastases not reaching significance (p = 0.060). In conclusion, diffusion MRI metrics are able to detect subtle differences in the free water content of perilesional T2 hyperintense areas in GBM and metastases, whereas DMI seems to be superior to DTI and NODDI

Abstract: Purpose To evaluate the diagnostic accuracy of epilepsy-dedicated 3 Tesla MRI including post-processing by correlating MRI, histopathology, and postsurgical seizure outcomes. Methods 3 Tesla-MRI including a magnetization-prepared two rapid acquisition gradient echo (MP2RAGE) sequence for post-processing using the morphometric analysis program MAP was acquired in 116 consecutive patients with drug-resistant focal epilepsy undergoing resection surgery. The MRI, histopathology reports and postsurgical seizure outcomes were recorded from the patient's charts. Results The MRI and histopathology were concordant in 101 and discordant in 15 patients, 3 no hippocampal sclerosis/gliosis only lesions were missed on MRI and 1 of 28 focal cortical dysplasia (FCD) type II associated with a glial scar was considered a glial scar only on MRI. In another five patients, MRI was suggestive of FCD, the histopathology was uneventful but patients were seizure-free following surgery. The MRI and histopathology were concordant in 20 of 21 glioneuronal tumors, 6 cavernomas, and 7 glial scars. Histopathology was negative in 10 patients with temporal lobe epilepsy, 4 of them had anteroinferior meningoencephaloceles. Engel class IA outcome was reached in 71% of patients. Conclusion The proposed MRI protocol is highly accurate. No hippocampal sclerosis/gliosis only lesions are typically MRI negative. Small MRI positive FCD can be histopathologically missed, most likely due to sampling errors resulting from insufficient harvesting of tissue