Explore the vast range of titles available.

Background: To investigate the accuracy of augmented reality (AR) navigation using the Magic Leap head mounted device (HMD), pedicle screws were minimally invasively placed in four spine phantoms. Methods: AR navigation provided by a combination of a conventional navigation system integrated with the Magic Leap head mounted device (AR-HMD) was used. Forty-eight screws were planned and inserted into Th11-L4 of the phantoms using the AR-HMD and navigated instruments. Postprocedural CT scans were used to grade the technical (deviation from the plan) and clinical (Gertzbein grade) accuracy of the screws. The time for each screw placement was recorded. Results: The mean deviation between navigation plan and screw position was 1.9 ± 0.7 mm (1.9 [0.3–4.1] mm) at the entry point and 1.4 ± 0.8 mm (1.2 [0.1–3.9] mm) at the screw tip. The angular deviation was 3.0 ± 1.4° (2.7 [0.4–6.2]°) and the mean time for screw placement was 130 ± 55 s (108 [58–437] s). The clinical accuracy was 94% according to the Gertzbein grading scale. Conclusion: The combination of an AR-HMD with a conventional navigation system for accurate minimally invasive screw placement is feasible and can exploit the benefits of AR in the perspective of the surgeon with the reliability of a conventional navigation system.

Background Ankylosing spinal disorders (ASD) increase the risk of unstable cervical spine fractures, posing a significant mortality risk. Surgery is recommended for patients with neurological deficits, but the effectiveness of non-surgical treatment in those without deficits remains unclear. This study aimed to compare survival rates between surgical and non-surgical treatments of ASD-related cervical fractures in a matched cohort. Methods The study analyzed data from the Swedish Fracture Registry (SFR) on adult patients treated for ASD-related cervical spine fractures between January 2015 and December 2021. Preoperative variables included age, sex, trauma type, neurological function, fracture morphology, and treatment method. Propensity score matching was conducted to compare outcomes between treatment groups, ensuring balanced comparison groups regarding age, sex, type of trauma, time from injury to admission, fracture type, level of injury, and neurological function. Results In total, 357 adult patients with ASD-related cervical spine fractures were analyzed. Among them, 186 were treated surgically and 171 non-surgically. Treatment failure and conversion so surgical treatment was seen in 3.4% of the non-surgically treated patients. Most patients were male (80%), with a median age of 75 years. Fractures were mainly caused by low-energy trauma (69%). Most patients (92%) were ambulatory (Frankel grade D or E). In the unmatched analysis, surgically treated patients had significantly lower 1-year mortality rates (13% vs. 22%; p  < 0.001), but after matching, there were no longer any difference between the two groups (16% vs. 22%; p  = 0.44). These findings were also validated on Kaplan–Meier analysis. Multivariable logistic regression analysis identified high age as the only predictor for 30-day mortality (OR 1.14 [95% CI 1.09—1.22], p  < 0.001). Conclusion Following propensity score matching, surgical and conservative management result in similar mortality outcomes for neurologically intact patients with ASD fractures. Age, rather than treatment approach, emerged as a stronger predictor of overall mortality. Nonetheless, treatment decisions should also consider other clinical outcomes beyond mortality, emphasizing the need for an individualized approach until more robust evidence is available.

Objective: The precision of neuronavigation systems relies on the correct registration of the patient’s position in space and aligning it with radiological 3D imaging data. Registration is usually performed by the acquisition of anatomical landmarks or surface matching based on facial features. Another possibility is automatic image registration using intraoperative imaging. This could provide better accuracy, especially in rotated or prone positions where the other methods may be difficult to perform. The aim of this study was to validate automatic image registration (AIR) using intraoperative cone-beam computed tomography (CBCT) for cranial neurosurgical procedures and compare the registration accuracy to the traditional surface matching (SM) registration method based on preoperative MRI. The preservation of navigation accuracy throughout the surgery was also investigated. Methods: Adult patients undergoing intracranial tumor surgery were enrolled after consent. A standard SM registration was performed, and reference points were acquired. An AIR was then performed, and the same reference points were acquired again. Accuracy was calculated based on the referenced and acquired coordinates of the points for each registration method. The reference points were acquired before and after draping and at the end of the procedure to assess the persistency of accuracy. Results: In total, 22 patients were included. The mean accuracy was 6.6 ± 3.1 mm for SM registration and 1.0 ± 0.3 mm for AIR. The AIR was superior to the SM registration (p < 0.0001), with a mean improvement in accuracy of 5.58 mm (3.71–7.44 mm 99% CI). The mean accuracy for the AIR registration pre-drape was 1.0 ± 0.3 mm. The corresponding accuracies post-drape and post-resection were 2.9 ± 4.6 mm and 4.1 ± 4.9 mm, respectively. Although a loss of accuracy was identified between the preoperative and end-of-procedure measurements, there was no statistically significant decline during surgery. Conclusions: AIR for cranial neuronavigation consistently delivered greater accuracy than SM and should be considered the new gold standard for patient registration in cranial neuronavigation. If intraoperative imaging is a limited resource, AIR should be prioritized in rotated or prone position procedures, where the benefits are the greatest.

This article addresses the question of experiential dimensions of space in sound, in electroacoustic music and sound arts practices in particular. We suggest that these practices are limited by the generalized way that spatial audio techniques are communicated, and we attempt to develop a tentative method that would allow for discussing and sharing spatial aspects in sonic environments. These modes of articulation would permit for a translation of the experience into other modalities. Reporting from a series of workshops, we outline a three-phase method that moves through stages of listening, describing, and recreating and imagining the sonic spaces. In the final stage a speculative design approach unveils that shared sonic spatial experiences are essentially relational. In the discussion, topics of expectations, biases, and language; concepts such as memory and imagination; and the methods mapping, and speculative design are addressed. Through the explorations presented in this article it becomes evident that different artistic musical practices show the same need to develop articulations allowing the integrating and communication of spatial relationships. The dichotomy between the development of new technologies for spatial audio and that of conceptual frameworks for understanding and communicating spatial sonic knowledge can be aligned and potentially even reinforce each other.

Departing from the artistic research project Goodbye Intuition (GI) hosted by the Norwegian Academy of Music in Oslo, this article discusses the aesthetics of improvising with machines. Playing with a system such as the one described in this article, with limited intelligence and no real cognitive skills, will obviously reveal the weaknesses of the system, but it will also convey part of the preconditions and aesthetic frameworks that the human improviser brings to the table. If we want the autonomous system to have the same kind of freedom we commonly value in human players’ improvisational practice, are we prepared to accept that it may develop in a direction that departs from our original aesthetical ambitions? The analyses is based on some of the documented interplay between the musicians in a group in workshops and laboratories. The question of what constitutes an ethical relationship in this kind of improvisation is briefly discussed. The aspect of embodiment emerges as a central obstacle in the development of musical improvisation with machines.

BackgroundHybrid operating rooms (hybrid-ORs) combine the functionalities of a conventional surgical theater with the advanced imaging technologies of a radiological suite. Hybrid-ORs are usually equipped with CBCT devices providing both 2D and 3D imaging capability that can be used for both interventional radiology and image guided surgical applications. Across all fields of surgery, the use of hybrid-ORs is gaining in traction, and neurosurgery is no exception. We hence aimed to comprehensively review the use of hybrid-ORs, the associated advantages, and disadvantages specific to the field of neurosurgery.Materials and methodsElectronic databases were searched for all studies on hybrid-ORs from inception to May 2022. Findings of matching studies were pooled to strengthen the current body of evidence.ResultsSeventy-four studies were included in this review. Hybrid-ORs were mainly used in endovascular surgery (n = 41) and spine surgery (n = 33). Navigation systems were the most common additional technology employed along with the CBCT systems in the hybrid-ORs. Reported advantages of hybrid-ORs included immediate assessment of outcomes, reduced surgical revision rate, and the ability to perform combined open and endovascular procedures, among others. Concerns about increased radiation exposure and procedural time were some of the limitations mentioned.ConclusionIn the field of neurosurgery, the use of hybrid-ORs for different applications is increasing. Hybrid-ORs provide preprocedure, intraprocedure, and end-of-procedure imaging capabilities, thereby increasing surgical precision, and reducing the need for postoperative imaging and correction surgeries. Despite these advantages, radiation exposure to patient and staff is an important concern.

Objective Gross total resection is strived for in intramedullary spinal cord lesion surgery. Intraoperative neurophysiological monitoring (IONM) is the gold standard, but there is no consensus on the optimal IONM workflow. This study details our institutional workflow. Methods We retrospectively reviewed all adults who underwent intramedullary resection at Karolinska University Hospital, 2007–2021 ( n  = 70). Continuous multimodal IONM (somatosensory-evoked potentials (SSEP), motor-evoked potentials (MEP) and epidural D-waves) was conducted by an in-room neurophysiologist. Alarm thresholds were preset (≥ 50% SSEP amplitude drop/10% latency rise; ≥ 80% MEP reduction; ≥ 50% D-wave loss) and triggered a standardized four-step rescue protocol (halt manipulation, raise MAP to 80–90 mm Hg, topical papaverine, observation). Motor/sensory function, modified McCormick (mMC) grade, pain, and sphincter control were documented pre-operatively, at 3 months, and ≥ 12 months. Results Seventy patients were included. Most harboured ependymoma (51%), hemangioblastoma (18%) and cavernoma (8.5%). A neurophysiologist was present during every procedure. A ≥ 50% intra-operative SSEP-amplitude decrease was not followed by a sensory deficit (OR:3.0, 95% CI 0.86–10.6; p  = 0.085) or mMC deterioration (OR:1.6, 0.33–7.5; p  = 0.57) at either short- or long-term follow-up. In contrast, complete SSEP loss markedly increased the risk of postoperative sensory deficit (3-months-OR:25.2, 4.7–135; p  < 0.001; long-term-OR 11.0, 2.8–43.8; p  < 0.001) and poorer mMC grade (3-months-OR:7.8, 2.0–31; p  = 0.004; long-term-OR:11.0, 2.8–43.8; p  < 0.001). Loss of MEPs predicted a decline in mMC at long-term follow-up (OR:4.0, 1.06–15.1; p  = 0.041). Conclusions Live data from continuous intraoperative neurophysiological monitoring, expertly interpreted in the OR, could potentially be used to make surgical and anesthesiologic adjustments with the goal of minimizing the risk of negative neurological outcomes. Significant associations were found between decreased or lost IONM signals and poorer sensorimotor function and mMC score at short- and long-term follow-up. Implementation of the IONM workflow is suggested in all intramedullary surgery.

BackgroundIntraoperative MRI (iMRI) has emerged as a useful tool in glioma surgery to safely improve the extent of resection. However, iMRI requires a dedicated operating room (OR) with an integrated MRI scanner solely for this purpose. Due to physical or economical restraints, this may not be feasible in all centers. The aim of this study was to investigate the feasibility of using a non-dedicated MRI scanner at the radiology department for iMRI and to describe the workflow with special focus on time expenditure and surgical implications.MethodsIn total, 24 patients undergoing glioma surgery were included. When the resection was deemed completed, the wound was temporarily closed, and the patient, under general anesthesia, was transferred to the radiology department for iMRI, which was performed using a dedicated protocol on 1.5 or 3 T scanners. After performing iMRI the patient was returned to the OR for additional tumor resection or final wound closure. All procedural times, timestamps, and adverse events were recorded.ResultThe median time from the decision to initiate iMRI until reopening of the wound after scanning was 68 (52–104) minutes. Residual tumors were found on iMRI in 13 patients (54%). There were no adverse events during the surgeries, transfers, transportations, or iMRI-examinations. There were no wound-related complications or infections in the postoperative period or at follow-up. There were no readmissions within 30 or 90 days due to any complication.ConclusionPerforming intraoperative MRI using an MRI located outside the OR department was feasible and safe with no adverse events. It did not require more time than previously reported data for dedicated iMRI scanners. This could be a viable alternative in centers without access to a dedicated iMRI suite.

BackgroundThe current shortage of radiology staff in healthcare provides a challenge for departments all over the world. This leads to more evaluation of how the radiology resources are used and a demand to use them in the most efficient way. Intraoperative MRI is one of many recent advancements in radiological practice. If radiology staff is performing intraoperative MRI at the operation ward, they may be impeded from performing other examinations at the radiology department, creating costs in terms of exams not being performed. Since this is a kind of cost whose importance is likely to increase, we have studied the practice of intraoperative MRI in Sweden.MethodsThe study includes data from the first four hospitals in Sweden that installed MRI scanners adjacent to the operating theaters. In addition, we included data from Karolinska University Hospital in Solna where intraoperative MRI is carried out at the radiology department.ResultsScanners that were moved into the operation theater and doing no or few other scans were used 11–12% of the days. Stationary scanners adjacent to the operation room were used 35–41% of the days. For scanners situated at the radiology department doing intraoperative scans interspersed among all other scans, the proportion was 92%.ConclusionOur study suggests that performing exams at the radiology department rather than at several locations throughout the hospital may be an efficient approach to tackle the simultaneous trends of increasing demands for imaging and increasing staff shortages at radiology departments.

Introduction Spinal navigation solutions have been slower to develop compared to cranial ones. To facilitate greater adoption and use of spinal navigation, the relatively cumbersome registration processes need to be improved upon. This study aims to validate a new solution for automatic image registration and compare it to a traditional Surface Matching method. Method Adult patients undergoing spinal surgery requiring navigation were enrolled after providing consent. A registration matrix—Universal AIR (= Automatic Image Registration)—was placed in the surgical field and used for automatic registration based on intraoperative 3D imaging. A standard Surface Matching method was used for comparison. Accuracy measurements were obtained by comparing planned and acquired coordinates on the vertebrae. Results Thirty-nine patients with 42 datasets were included. The mean accuracy of Universal AIR registration was 1.20 ± 0.42 mm, while the mean accuracy of Surface Matching registration was 1.94 ± 0.64 mm. Universal AIR registration was non-inferior to Surface Matching registration. Post hoc analysis showed a significantly greater accuracy for Universal AIR registration. In Surface Matching, but not automatic registration, user-related errors such as incorrect identification of the vertebral level were seen. Conclusion Automatic image registration for spinal navigation using Universal AIR and intraoperative 3D imaging provided improved accuracy compared to Surface Matching registration. In addition, it minimizes user errors and offers a standardized workflow, making it a reliable registration method for navigated spinal procedures.