Cost-effectiveness of Intraoperative MRI for Treatment of High-Grade Gliomas

Cost utility analysis of adult patients with severe aplastic anemia: a single-center study

OBJECTIVE

There is a need for real-world studies in China to help address evidence gaps supporting precise clinical decision-making with respect to the ideal treatment options for patients with severe aplastic anemia (SAA). Accordingly, we objectively evaluated the efficacy of cyclosporine A (CsA) + antilymphocyte globulin (ALG) versus CsA + thrombopoietin receptor agonist (TPO-RA) for such patients.

METHODS

A cost-utility analysis (CUA) was conducted to compare the quality-adjusted life years (QALY) and total costs associated with the two treatment regimens. Patient utility values were derived from the European Quality-of-Life 5 Dimensions 3 Level Version (EQ-5D-3L) using the Japanese time trade-off conversion method.

RESULTS

Patients receiving the CsA + ALG regimen reported higher subjective well-being than those treated with the CsA + TPO-RA regimen from the time of hospital admission through 6 months of follow-up. In addition, the quality-of-life of patients in the CsA + ALG group was significantly higher than that of the patients in the CsA + TPO-RA group, with a difference of 0.08 QALY (P < 0.01). However, the total cost of the CsA + ALG regimen was nearly twice that of the CsA + TPO-RA regimen. The incremental cost per QALY gained with the CsA + ALG regimen relative to the CsA + TPO-RA regimen was 1.63 million yuan.

CONCLUSIONS

This study utilized CUA to comparatively assess the cost-effectiveness of CsA + ALG and CsA + TPO-RA regimens in the treatment of SAA. Although both regimens were found to be effective, the CsA + TPO-RA regimen presented a viable treatment option with assured therapeutic efficacy while reducing the financial burden, thereby offering greater benefits for patients with SAA and alleviating the societal healthcare costs.

Preoperative and intraoperative neuromonitoring and mapping techniques impact oncological and functional outcomes in supratentorial function-eloquent brain tumours: a systematic review and meta-analysis

Background

Supratentorial function-eloquent brain tumour surgeries challenge the balance between maximal tumour resection and preservation of neurological function. This study aims to evaluate the efficacy of preoperative and intraoperative mapping techniques on resection outcomes and post-operative deficits.

Methods

This systematic review and meta-analysis examined literature up to March 2023, sourced from PubMed, Embase, and Medline. Criteria for inclusion were studies on patients undergoing surgery for supratentorial brain tumours, comparing preoperative mapping only (POM), intraoperative neuromonitoring and mapping (IONM), and combined techniques (POM&IONM), excluding non-randomized controlled trials. Data extraction focused on rates of gross total resection (GTR) and focal neurological deficits (FNDs). The main outcomes, assessed through a random-effects model and Cochran's Q-test for subgroup analysis. The study protocol is published on PROSPERO CRD42024512306.

Findings

19 studies involving 992 patients were included. Systematic review with meta-analysis revealed a non-significantly higher average GTR rates for POM&IONM (49.13%) and POM (50.79%) compared to IONM alone (41.23%). Highest rates of GTR were achieved with tractography-guided resection in POM group (66.59% versus fMRI-20.00%, p = 0.0004), multimodal stimulation in IONM group (54.16% versus low frequency stimulation (LFS)-13.29%, p < 0.0001) and in POM&IONM group (65.88% versus LFS-37.77%, p = 0.0036). Within the same tumour histology-metastasis, high grade and low grade glioma-there are no differences in the GTR rates achieved in the different groups (p > 0.05). In language-eloquent tumours and in awake craniotomy techniques regardless of tumour functional eloquence, POM&IONM group had higher GTR when compared to IONM groups (language eloquent tumours-POM&IONM 43.31% versus IONM-15.09%, p = 0.022; awake craniotomy technique-POM&IONM-41.22% versus IONM-12.08%, p = 0.0006). Permanent FNDs were higher in the IONM group (IONM-73.0%; POM-29.6%; POM&IONM-33.7% of immediate postoperative deficits, p = 0.0010).

Interpretation

A combined POM&IONM approach is responsible for higher rates of GTR in patients with language eloquent tumours and in both awake and asleep craniotomy techniques regardless of the tumour functional eloquence. The tumour histology is not relevant for differences in GTR rates among different mapping and monitoring strategies. Permanent postoperative FNDs are more likely with standalone utilization of IONM.

Funding

Not applicable.

Comparing the Rates of Further Resection After Intraoperative MRI Visualisation of Residual Tumour Between Brain Tumour Subtypes: A 17-Year Single-Centre Experience

BACKGROUND

Maximal safe resection is the objective of most neuro-oncological operations. Intraoperative magnetic resonance imaging (iMRI) may guide the surgeon to improve the extent of safe resection. There is limited evidence comparing the impact of iMRI on the rates of further resection between tumour types.

AIM

To investigate the impact of iMRI on the rate of further resection following visualisation of residual tumour.

METHODS

A retrospective cohort study identified all intracranial tumour operations performed in the 1.5 T iMRI machine of a single centre (2007-2023). Patients were identified using SurgiNet and were grouped according to their histopathological diagnosis in accordance with the WHO 2021 classification. The primary outcome was the rate of reoperation due to iMRI visualisation of residual tumours.

RESULTS

A total of 574 cases were identified, including 152 low-grade gliomas (LGG), 108 high-grade gliomas (HGG), 194 pituitary neuroendocrine tumours (PitNETs), 15 metastases, and 6 meningiomas. Further resection following iMRI visualisation occurred in 45% of LGG cases, 47% of HGG cases, 29% of PitNET cases, and no meningioma or metastasis cases. Chi-square analysis showed that the rate of further resection after iMRI use across 2018-2023 was significantly higher than that across 2007-2012 (46% versus 33%, p = 0.036).

CONCLUSION

Intraoperative MRI for guiding further resection was most useful in cases of LGG and HGG, possibly reflecting the difficulty of differentiating these tumour types from normal brain tissue. In addition, there was increased reliance on iMRI over time, which may represent our surgeons becoming accustomed to its use.

Impact of intraoperative MRI on pediatric epilepsy surgery for focal cortical dysplasia

BACKGROUND

Complete resection is essential for achieving seizure freedom in children with drug-resistant epilepsy due to focal cortical dysplasia (FCD). However, identifying altered structures intraoperatively can be challenging, potentially leading to reoperations. This study assessed the impact of intraoperative MRI (iMRI).

METHODS

We conducted a single-center retrospective study at Alder Children's Hospital from 2013 to 2022. The study included all children diagnosed with FCD, analyzing demographics, iMRI use, the rate of continued iMRI-guided surgery and reoperations, histology, and seizure outcomes at 1-year follow-up.

RESULTS

Thirty-two pediatric patients (median age: 10 years, 21 males and 11 females) underwent surgery for FCD. Of them 8 (25 %) had FCD Type I, 19 (59.4 %) had FCD Type II, and 1 patient (3.1 %) had FCD Type III. iMRI was used in 27 patients (84.4 %), and 17 (63 %) of these patients required further iMRI-guided surgery. Four patients underwent reoperation in a separate session. At 1-year follow-up, seizure outcomes in the iMRI group were Engel I in 15 patients (71.4 %), Engel II in 4 (19 %), and Engel III and IV in 1 patient (4.8 %) each. Five patients (15.6 %) had superficially localized lesions and underwent surgery without iMRI. None of them required reoperation, and four (80 %) were seizure-free at 1 year. Seven patients were lost to follow-up.

CONCLUSION

iMRI plays a significant role in identifying residual epileptogenic tissue in surgery for FCD, influencing surgical decisions and leading to additional iMRI-guided resections. Most patients with iMRI-guided surgery achieved favorable seizure outcomes (Engel I) at 1 year of follow-up. Long-term follow-up is needed to validate these findings and to confirm sustained seizure control.

Characterization of Polarimetric Properties in Various Brain Tumor Types Using Wide-Field Imaging Mueller Polarimetry

Neuro-oncological surgery is the primary brain cancer treatment, yet it faces challenges with gliomas due to their invasiveness and the need to preserve neurological function. Hence, radical resection is often unfeasible, highlighting the importance of precise tumor margin delineation to prevent neurological deficits and improve prognosis. Imaging Mueller polarimetry, an effective modality in various organ tissues, seems a promising approach for tumor delineation in neurosurgery. To further assess its use, we characterized the polarimetric properties by analysing 45 polarimetric measurements of 27 fresh brain tumor samples, including different tumor types with a strong focus on gliomas. Our study integrates a wide-field imaging Mueller polarimetric system and a novel neuropathology protocol, correlating polarimetric and histological data for accurate tissue identification. An image processing pipeline facilitated the alignment and overlay of polarimetric images and histological masks. Variations in depolarization values were observed for grey and white matter of brain tumor tissue, while differences in linear retardance were seen only within white matter of brain tumor tissue. Notably, we identified pronounced optical axis azimuth randomization within tumor regions. This study lays the foundation for machine learning-based brain tumor segmentation algorithms using polarimetric data, facilitating intraoperative diagnosis and decision making.

Healthcare spending versus mortality in central nervous system cancer: Has anything changed?

Background

The financial implications of central nervous system (CNS) cancers are substantial, not only for the healthcare service and payers, but also for the patients who bear the brunt of direct, indirect, and intangible costs. This study sought to investigate the impact of healthcare spending on CNS cancer survival using recent US data.

Methods

This study used public data from the Disease Expenditure Project 2016 and the Global Burden of Disease Study 2019. The primary outcome was the annual healthcare spending trend from 1996 and 2016 on CNS tumors adjusted for disease prevalence, alongside morbidity and mortality. Secondary outcomes included drivers of change in healthcare expenditures for CNS cancers. Subgroup analysis was performed stratified by age group, expenditure type, and care type provided.

Results

There was a significant increase in total healthcare spending on CNS cancers from $2.72 billion (95% CI: $2.47B to $2.97B) in 1996 to $6.85 billion (95% CI: $5.98B to $7.57B) in 2016. Despite the spending increase, the mortality rate per 100 000 people increased, with 5.30 ± 0.47 in 1996 and 7.02 ± 0.47 in 2016, with an average of 5.78 ± 0.47 deaths per 100 000 over the period. The subgroups with the highest expenditure included patients aged 45 to 64, those with private insurance, and those receiving inpatient care.

Conclusions

This study highlights a significant rise in healthcare costs for CNS cancers without corresponding improvements in mortality rate, indicating a mismatch of healthcare spending, contemporary advances, and patient outcomes as it relates to mortality.

Observations from the first 100 cases of intraoperative MRI - experiences, trends and short-term outcomes

BACKGROUND

We sought to analyze, in well-defined clinical setting, the first 100 patients treated at the intraoperative MRI (iMRI) hybrid surgical theatre at our facility in a population-based setting to evaluate which pathologies are best approached with iMRI assisted surgeries, as this is not yet clearly defined.

METHODS

Patients undergoing surgery in the 3T iMRI hybrid surgical theatre at our neurosurgical department between December 2017 to May 2021 were included after informed consent. Demographic, clinical, surgical, histological, radiological and outcome parameters, as well as variables related to iMRI, were retrospectively collected and analyzed. Patients were subdivided into adult and pediatric cohorts.

RESULTS

Various neurosurgical procedures were performed; resection of tumors and epileptic foci, endoscopic skull base procedures including pituitary lesions, deep brain stimulation (DBS) and laser interstitial thermal therapy (LITT). In total, 41 patients were pediatric. An iMRI scan was carried out in 96% of cases and led to continuation of surgery in 50% of cases, mainly due to visualized remaining pathological tissue (95.2%). Median time to iMRI from intubation was 280 min and median total duration of surgery was 445 min. The majority of patients experienced no postoperative complications (70%), 13 patients suffered permanent postoperative deficits, predominantly visual.

CONCLUSION

Herein, we demonstrate the first 100 patients undergoing neurosurgery aided by iMRI at our facility since introduction. Indications for surgery differed between pediatric and adult patients. The iMRI was utilized for tumor surgeries, particularly adult low-grade gliomas and pediatric tumors, as well as for epilepsy surgery and DBS. In this heterogenous population, iMRI led to continuation of surgery in 50%. To establish the benefit in maximizing the extent of resection in these brain pathologies future studies are recommended.

CLINICAL TRIAL NUMBER

Not applicable.

Intraoperative MRI: A Review of Applications Across Neurosurgical Specialties

Intraoperative MRI (iMRI) made its debut to great fanfare in the mid-1990s. However, the enthusiasm for this technology with seemingly obvious benefits for neurosurgeons has waned. We review the benefits and utility of iMRI across the field of neurosurgery and present an overview of the evidence for iMRI for multiple neurosurgical disciplines: tumor, skull base, vascular, pediatric, functional, and spine. Publications on iMRI have steadily increased since 1996, plateauing with approximately 52 publications per year since 2011. Tumor surgery, especially glioma surgery, has the most evidence for the use of iMRI contributing more than 50% of all iMRI publications, with increased rates of gross total resection in both adults and children, providing a potential survival benefit. Across multiple neurosurgical disciplines, the ability to use a multitude of unique sequences (diffusion tract imaging, diffusion-weighted imaging, magnetic resonance angiography, blood oxygenation level-dependent) allows for specialization of imaging for various types of surgery. Generally, iMRI allows for consideration of anatomic changes and real-time feedback on surgical outcomes such as extent of resection and instrument (screw, lead, electrode) placement. However, implementation of iMRI is limited by cost and feasibility, including the need for installation, shielding, and compatible tools. Evidence for iMRI use varies greatly by specialty, with the most evidence for tumor, vascular, and pediatric neurosurgery. The benefits of real-time anatomic imaging, a lack of radiation, and evaluation of surgical outcomes are limited by the cost and difficulty of iMRI integration. Nonetheless, the ability to ensure patients are provided by a maximal yet safe treatment that specifically accounts for their own anatomy and highlights why iMRI is a valuable and underutilized tool across multiple neurosurgical subspecialties.

Financing of Neurosurgical Care for Brain Tumors in Low- and Middle-Income Countries : A Scoping Review of Barriers and Strategies

BACKGROUND

Making neurosurgical care accessible to a larger portion of the population in low- and middle-income countries (LMICs) is integral due to the high mortality and morbidity associated with brain tumors. However, the high cost of care often makes it financially out of reach for many individuals. Therefore, this review aims to identify barriers to neurosurgical care of brain tumors in terms of financing in LMICs.

METHODS

Without restriction to language, a search of the literature was undertaken in a number of databases, including PubMed, Scopus, Google Scholar, and CINAHL, in order to find the most pertinent research involving financing of brain tumors in LMICs. The last day of the search was October 20, 2022. Following screening and data extraction, significant themes were found and categorized using thematic analysis.

RESULTS

A total of 28 studies were analyzed in this review. The review highlighted some of the barriers to providing surgical care of brain tumors in LMICs. In the cited studies, surgical expenses (41%), neuroimaging costs (30%), and care-related expenses (33%) were the primary concerns. Addressing these challenges involves cross-border collaboration (23%), transparent financing systems (46%), awake craniotomy (15%), cost-effective/reusable intra-operative supplies (8%), and optimizing resources in healthcare systems (8%).

CONCLUSIONS

This study explored barriers and challenges to financing neurosurgical care of brain tumors in LMICs. Government support and transparency in healthcare financing should be prioritized to ensure that all individuals have access to surgical care of brain tumors.

Pharmaceutical equivalent 5-aminolevulinic acid fluorescence guided resection of central nervous system tumors: feasibility, safeness and cost-benefit considerations

PURPOSE

5-aminolevulinic acid (5-ALA) fluorescence-guided resection (FGR) has been an essential tool in the 'standard of care' of malignant gliomas. Over the last two decades, its indications have been extended to other neoplasms, such as metastases and meningiomas. However, its availability and cost-benefit still pose a challenge for widespread use. The present article reports a retrospective series of 707 cases of central nervous system (CNS) tumors submitted to FGR with pharmacological equivalent 5-ALA and discusses financial implications, feasibility and safeness.

METHODS

From December 2015 to February 2024, a retrospective single institution series of 707 cases of 5-ALA FGR were analyzed. Age, gender, 5-ALA dosage, intraoperative fluorescence finding, diagnosis and adverse effects were recorded. Financial impact in the surgical treatment cost were also reported.

RESULTS

there was an additional cost estimated in $300 dollars for each case, increasing from 2,37 to 3,28% of the total hospitalization cost. There were 19 (2,69%) cases of asymptomatic photosensitive reaction and 2 (0,28%) cases of photosensitive reaction requiring symptomatic treatment. 1 (0,14%) patient had a cutaneous rash sustained for up to 10 days. No other complications related to the method were evident. In 3 (0,42%) cases of patients with intracranial hypertension, there was vomiting after administration.

CONCLUSION

FGR with pharmacological equivalent 5-ALA can be considered safe and efficient and incorporates a small increase in hospital expenses. It constitutes a reliable solution in avoiding prohibitive costs worldwide, especially in countries where commercial 5-ALA is unavailable.

Transoperative Magnetic Resonance Imaging in Awake Glioma Surgery: Experience in a Latin American Tertiary-Level Center

OBJECTIVE

Analyze the usefulness, efficacy, and safety of transoperative magnetic resonance imaging (tMRI) in glioma surgery in awake patients.

METHODS

Retrospective, single-center, analytical study of a cohort of patients who underwent awake surgery for gliomas by the same surgeon in a third-level Argentine center, in the period between 2012 and 2022. Only patients with pathology-confirmed gliomas, with 6-month follow-up, who had preoperative and postoperative volumetric magnetic resonance imaging, were included in this sample. Subsequently, we analyzed which patients received surgery with the tMRI protocol and the results using multivariate regression analysis.

RESULTS

A total of 71 patients were included. A tMRI study was performed on 22 (31%) of these patients. The use of tMRI increased the percentage of resection by 20% (P = 0.03), thereby increasing the possibility of gross total resection. However, using tMRI significantly extended surgical time by 84 minutes (P < 0.001). In 55% of the patients in whom tMRI was performed, the resection was continued after it. The use of tMRI did not increase the rate of infections or the development of surgically associated neurological deficits in the long term, despite the fact that 47% of the patients showed the development of a new deficit or worsening of a previous one during the intraoperative period.

CONCLUSIONS

The use of tMRI in awake glioma surgery proved to be a safe tool that contributes to increasing the degree of tumor resection, compared to the use of neurophysiological mapping and neuronavigation, at the expense of increased surgical times and costs. We consider tMRI in awake glioma surgery should be used in properly selected cases.

Bridging the Global Technology Gap in Neurosurgery: Disparities in Access to Advanced Tools for Brain Tumor Resection

BACKGROUND AND OBJECTIVES

The advent of advanced technologies has brought unprecedented precision and efficacy to neurosurgical procedures for brain tumor resection. Despite the remarkable progress, disparities in technology access across different nations persist, creating significant challenges in providing equitable neurosurgical care. The purpose of the following work was to comprehensively analyze the existing disparities in access to innovative neurosurgical technologies and the impact of such disparities on patient outcomes and research. We seek to shed light on the extent of the problem, the underlying causes, and propose strategies for mitigating these disparities.

METHODS

A systematic review of published articles, including clinical studies, reports, and healthcare infrastructure assessments, was conducted to gather data on the availability and utilization of advanced neurosurgical technologies in various countries.

RESULTS

Disparities in technology access in neurosurgery are evident, with high-income countries benefiting from widespread implementation, while low- and middle-income countries face significant challenges in technology adoption. These disparities contribute to variations in surgical outcomes and patient experiences. The root causes of these disparities encompass financial constraints, inadequate infrastructure, and insufficient training and expertise.

CONCLUSION

Disparities in access to advanced neurosurgical technology remain a critical concern in global neurosurgery. Bridging this gap is essential to ensure that all patients, regardless of their geographic location, can benefit from the advancements in neurosurgical care. A concerted effort involving governments, healthcare institutions, and the international community is required to achieve this goal, advancing the quality of care for patients with brain tumors worldwide.

Advancement of fluorescent aminopeptidase probes for rapid cancer detection-current uses and neurosurgical applications

Surgical resection is considered for most brain tumors to obtain tissue diagnosis and to eradicate or debulk the tumor. Glioma, the most common primary malignant brain tumor, generally has a poor prognosis despite the multidisciplinary treatments with radical resection and chemoradiotherapy. Surgical resection of glioma is often complicated by the obscure border between the tumor and the adjacent brain tissues and by the tumor's infiltration into the eloquent brain. 5-aminolevulinic acid is frequently used for tumor visualization, as it exhibits high fluorescence in high-grade glioma. Here, we provide an overview of the fluorescent probes currently used for brain tumors, as well as those under development for other cancers, including HMRG-based probes, 2MeSiR-based probes, and other aminopeptidase probes. We describe our recently developed HMRG-based probes in brain tumors, such as PR-HMRG, combined with the existing diagnosis approach. These probes are remarkably effective for cancer cell recognition. Thus, they can be potentially integrated into surgical treatment for intraoperative detection of cancers.

Two years of neurosurgical intraoperative MRI in Sweden - evaluation of use and costs

BACKGROUND

The 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.

METHODS

The 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.

RESULTS

Scanners 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%.

CONCLUSION

Our 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.

Current Aspects of Intraoperative High-Field (3T) Magnetic Resonance Imaging in Pediatric Neurosurgery: Experiences from a Recently Launched Unit at a Tertiary Referral Center

OBJECTIVE

To evaluate the neurosurgical and economic effectiveness of a newly launched intraoperative high-field (3T) magnetic resonance imaging (MRI) suite for pediatric tumor and epilepsy neurosurgery.

METHODS

Altogether, 148 procedures for 124 pediatric patients (mean age, 8.7 years; range, 0-18 years) within a 2.5-year period were undertaken in a 2-room intraoperative MRI (iopMRI) suite. Surgery was performed mainly for intractable epilepsy (n = 81; 55%) or pediatric brain tumors (n = 65; 44%) in the supine (n = 113; 76%) and prone (n = 35; 24%) positions. The mean time of iopMRI from draping to re-surgery was 50 minutes.

RESULTS

IopMRI was applied not in all but in 64 of 148 procedures (43%); in 45 procedures (31%), iopMRI was estimated unnecessary at the end of surgery based on the leading surgeon's decision. In the remaining 39 procedures (26%), ultra-early postoperative MRI was carried out after closure with the patient still sterile in the head coil. Of the 64 procedures with iopMRI, second-look surgery was performed in 26% (in epilepsy surgery in 17%, in tumor surgery in 9%). We did not encounter any infections, wound revisions, or position-related or anesthesiology-related complications.

CONCLUSIONS

We used iopMRI in less than half of pediatric tumor and epilepsy surgery for which it was scheduled initially. Therefore, high costs argue against its routine use in pediatric neurosurgery, although it optimized surgical results in one quarter of patients and met high safety standards.

Comparison meta-analysis of intraoperative MRI-guided needle biopsy versus conventional stereotactic needle biopsies

Background

MRI-guided needle biopsy (INB) is an emerging alternative to conventional frame-based or frameless stereotactic needle biopsy (SNB). Studies of INB have been limited to select case series, and comparative studies between INB and SNB remain a missing gap in the literature. We performed a meta-analysis to compare INB and SNB literature in terms of diagnostic yield, surgical morbidity and mortality, tumor size, and procedural time.

Methods

We identified 36 separate cohorts in 26 studies of SNB (including both frameless and frame-based biopsies, 3374 patients) and 27 studies of INB (977 patients). Meta-regression and meta-analysis by proportions were performed.

Results

Relative to publications that studied SNB, publications studying INB more likely involved brain tumors located in the eloquent cerebrum (79.4% versus 62.6%, P = 0.004) or are smaller in maximal diameter (2.7 cm in INB group versus 3.6 cm in the SNB group, P = .032). Despite these differences, the pooled estimate of diagnostic yield for INB was higher than SNB (95.4% versus 92.3%, P = .026). The pooled estimate of surgical morbidity was higher in the SNB group (12.0%) relative to the INB group (6.1%) (P = .004). Mortality after the procedure was comparable between INB and SNB (1.7% versus 2.3%, P = .288). Procedural time was statistically comparable at 90.3 min (INB) and 103.7 min (SNB), respectively (P = .526).

Conclusions

Our meta-analysis indicates that, relative to SNB, INB is more often performed for the challenging, smaller-sized brain tumors located in the eloquent cerebrum. INB is associated with lower surgical morbidity and improved diagnostic yield.

A Novel Portable, Mobile MRI: Comparison with an Established Low-Field Intraoperative MRI System

Background  MRI (magnetic resonance imaging) using low-magnet field strength has unique advantages for intraoperative use. We compared a novel, compact, portable MR imaging system to an established intraoperative 0.15 T system to assess potential utility in intracranial neurosurgery. Methods  Brain images were acquired with a 0.15 T intraoperative MRI (iMRI) system and a 0.064 T portable MR system. Five healthy volunteers were scanned. Individual sequences were rated on a 5-point (1 to 5) scale for six categories: contrast, resolution, coverage, noise, artifacts, and geometry. Results  Overall, the 0.064 T images (M = 3.4, SD = 0.1) had statistically higher ratings than the 0.15 T images (M = 2.4, SD = 0.2) ( p  < 0.01). All comparable sequences (T1, T2, T2 FLAIR and SSFP) were rated significantly higher on the 0.064 T and were rated 1.2 points (SD = 0.3) higher than 0.15 T scanner, with the T2 fluid-attenuated inversion recovery (FLAIR) sequences showing the largest increment on the 0.064 T with an average rating difference of 1.5 points (SD = 0.2). Scanning time for the 0.064 T system obtained images more quickly and encompassed a larger field of view than the 0.15 T system. Conclusions  A novel, portable 0.064 T self-shielding MRI system under ideal conditions provided images of comparable quality or better and faster acquisition times than those provided by the already well-established 0.15 T iMR system. These results suggest that the 0.064 T MRI has the potential to be adapted for intraoperative use for intracranial neurosurgery.

Robustness of the wide-field imaging Mueller polarimetry for brain tissue differentiation and white matter fiber tract identification in a surgery-like environment: an ex vivo study

During neurooncological surgery, the visual differentiation of healthy and diseased tissue is often challenging. Wide-field imaging Muller polarimetry (IMP) is a promising technique for tissue discrimination and in-plane brain fiber tracking in an interventional setup. However, the intraoperative implementation of IMP requires realizing imaging in the presence of remanent blood, and complex surface topography resulting from the use of an ultrasonic cavitation device. We report on the impact of both factors on the quality of polarimetric images of the surgical resection cavities reproduced in fresh animal cadaveric brains. The robustness of IMP is observed under adverse experimental conditions, suggesting a feasible translation of IMP for in vivo neurosurgical applications.

Intraoperative MRI use in transsphenoidal surgery for pituitary tumors: Trends and healthcare utilization

BACKGROUND

Intraoperative magnetic resonance imaging (iMRI) use in transsphenoidal approach (TSA) for pituitary tumors (PTs) has been reported to improve the extent of resection (EOR). The aim of this study is to report the trends and the impact of iMRI on healthcare utilization in patients who underwent TSA for PTs.

MATERIALS AND METHODS

MarketScan database were queried using the ICD-9/10 and CPT-4, from 2004 to 2020. We included patients ≥ 18 years of age PTs with > 1 year follow-up. Outcomes were length of stay (LOS), discharge disposition, hospital/emergency room (ER) re-admissions, outpatient services, medication refills and corresponding payments.

RESULTS

A cohort of 10,192 patients were identified from the database, of these 141 patients (1.4%) had iMRI used during the procedure. Use of iMRI for PTs remained stable (2004-2007: 0.85%; 2008-2011: 1.6%; 2012-2015:1.4% and 2016-2019: 1.46%). No differences in LOS (median 3 days each), discharge to home (93% vs. 94%), complication rates (7% vs. 13%) and payments ($34604 vs. $33050) at index hospitalization were noted. Post-discharge payments were not significantly different without and with iMRI use at 6-months ($8315 vs. $ 7577, p = 0.7) and 1-year ($13,654 vs. $ 14,054, p = 0.70), following the index procedure.

CONCLUSION

iMRI use during TSA for PTs remained stable with no impact on LOS, complications, discharge disposition and index payments. Also, there was no difference in combined index payments at 6-months, and 1-year after the index procedure in patients with and without iMRI use for PTs.

Advances in the intraoperative delineation of malignant glioma margin

Surgery plays a critical role in the treatment of malignant glioma. However, due to the infiltrative growth and brain shift, it is difficult for neurosurgeons to distinguish malignant glioma margins with the naked eye and with preoperative examinations. Therefore, several technologies were developed to determine precise tumor margins intraoperatively. Here, we introduced four intraoperative technologies to delineate malignant glioma margin, namely, magnetic resonance imaging, fluorescence-guided surgery, Raman histology, and mass spectrometry. By tracing their detecting principles and developments, we reviewed their advantages and disadvantages respectively and imagined future trends.

Review of Intraoperative Adjuncts for Maximal Safe Resection of Gliomas and Its Impact on Outcomes

Maximal safe resection is the mainstay of treatment in the neurosurgical management of gliomas, and preserving functional integrity is linked to favorable outcomes. How these modalities differ in their effectiveness on the extent of resection (EOR), survival, and complications remains unknown. A systematic literature search was performed with the following inclusion criteria: published between 2005 and 2022, involving brain glioma surgery, and including one or a combination of intraoperative modalities: intraoperative magnetic resonance imaging (iMRI), awake/general anesthesia craniotomy mapping (AC/GA), fluorescence-guided imaging, or combined modalities. Of 525 articles, 464 were excluded and 61 articles were included, involving 5221 glioma patients, 7(11.4%) articles used iMRI, 21(36.8%) used cortical mapping, 15(24.5%) used 5-aminolevulinic acid (5-ALA) or fluorescein sodium, and 18(29.5%) used combined modalities. The heterogeneity in reporting the amount of surgical resection prevented further analysis. Progression-free survival/overall survival (PFS/OS) were reported in 18/61(29.5%) articles, while complications and permanent disability were reported in 38/61(62.2%) articles. The reviewed studies demonstrate that intraoperative adjuncts such as iMRI, AC/GA mapping, fluorescence-guided imaging, and a combination of these modalities improve EOR. However, PFS/OS were underreported. Combining multiple intraoperative modalities seems to have the highest effect compared to each adjunct alone.

Innovations in the Diagnosis and Surgical Management of Low-Grade Gliomas

Low-grade gliomas are a broad category of tumors that can manifest at different stages of life. As a group, their prognosis has historically been considered to be favorable, and surgery is a mainstay of treatment. Advances in the molecular characterization of individual lesions has led to newer classification systems, a better understanding of the biological behavior of different neoplasms, and the identification of previously unrecognized entities. New prospective genetic and molecular data will help delineate better treatment paradigms and will continue to change the taxonomy of central nervous system tumors in the coming years. Advances in the field of radiomics will help predict the molecular profile of a particular tumor through noninvasive testing. Similarly, more precise methods of intraoperative tumor tissue analysis will aid surgical planning. Improved surgical outcomes propelled by novel surgical techniques and intraoperative adjuncts and emerging forms of medical treatment in the field of immunotherapy have enriched the management of these lesions. We review the contemporary management and innovations in the treatment of low-grade gliomas.

Intraoperative MRI versus intraoperative ultrasound in pediatric brain tumor surgery: is expensive better than cheap? A review of the literature

PURPOSE

The extent of brain tumor resection (EOR) is a fundamental prognostic factor in pediatric neuro-oncology in association with the histology. In general, resection aims at gross total resection (GTR). Intraoperative imaging like intraoperative US (iOUS) and MRI have been developed in order to find any tumoral remnant but with different costs. Aim of our work is to review the current literature in order to better understand the differences between costs and efficacy of MRI and iOUS to evaluate tumor remnants intraoperatively.

METHODS

We reviewed the existing literature on PubMed until 31st December 2021 including the sequential keywords "intraoperative ultrasound and pediatric brain tumors", "iUS and pediatric brain tumors", "intraoperative magnetic resonance AND pediatric brain tumors", and "intraoperative MRI AND pediatric brain tumors.

RESULTS

A total of 300 papers were screened through analysis of title and abstract; 254 were excluded. After selection, a total of 23 articles were used for this systematic review. Among the 929 patients described, a total of 349(38%) of the cases required an additional resection after an iMRI scan. GTR was measured on 794 patients (data of 69 patients lost), and it was achieved in 552(70%) patients. In case of iOUS, GTR was estimated in 291 out of 379 (77%) cases. This finding was confirmed at the post-operative MRI in 256(68%) cases.

CONCLUSIONS

The analysis of the available literature demonstrates that expensive equipment does not always mean better. In fact, for the majority of pediatric brain tumors, iOUS is comparable to iMRI in estimating the EOR.

Intelligent Ultra-Light Deep Learning Model for Multi-Class Brain Tumor Detection

The diagnosis and surgical resection using Magnetic Resonance (MR) images in brain tumors is a challenging task to minimize the neurological defects after surgery owing to the non-linear nature of the size, shape, and textural variation. Radiologists, clinical experts, and brain surgeons examine brain MRI scans using the available methods, which are tedious, error-prone, time-consuming, and still exhibit positional accuracy up to 2–3 mm, which is very high in the case of brain cells. In this context, we propose an automated Ultra-Light Brain Tumor Detection (UL-BTD) system based on a novel Ultra-Light Deep Learning Architecture (UL-DLA) for deep features, integrated with highly distinctive textural features, extracted by Gray Level Co-occurrence Matrix (GLCM). It forms a Hybrid Feature Space (HFS), which is used for tumor detection using Support Vector Machine (SVM), culminating in high prediction accuracy and optimum false negatives with limited network size to fit within the average GPU resources of a modern PC system. The objective of this study is to categorize multi-class publicly available MRI brain tumor datasets with a minimum time thus real-time tumor detection can be carried out without compromising accuracy. Our proposed framework includes a sensitivity analysis of image size, One-versus-All and One-versus-One coding schemes with stringent efforts to assess the complexity and reliability performance of the proposed system with K-fold cross-validation as a part of the evaluation protocol. The best generalization achieved using SVM has an average detection rate of 99.23% (99.18%, 98.86%, and 99.67%), and F-measure of 0.99 (0.99, 0.98, and 0.99) for (glioma, meningioma, and pituitary tumors), respectively. Our results have been found to improve the state-of-the-art (97.30%) by 2%, indicating that the system exhibits capability for translation in modern hospitals during real-time surgical brain applications. The method needs 11.69 ms with an accuracy of 99.23% compared to 15 ms achieved by the state-of-the-art to earlier to detect tumors on a test image without any dedicated hardware providing a route for a desktop application in brain surgery.

Use of intraoperative MRI for resection of intracranial tumors: A nationwide analysis of short-term outcomes

OBJECTIVE

Recent evidence supports the use of intraoperative MRI (iMRI) during resection of intracranial tumors due to its demonstrated efficacy and clinical benefit. Though many single-center investigations have been conducted, larger nationwide outcomes have yet to be characterized.

METHODS

We used the American College of Surgeons National Surgical Quality Improvement Program database to examine baseline characteristics and 30-day postoperative outcomes among patients undergoing craniotomy for tumor resection with and without iMRI. Comparisons between outcomes were accomplished after propensity matching using chi-square tests for categorical variables and Welch two-sample t-tests for continuous variables.

RESULTS

A total of 38,003 patients met inclusion criteria. Of this population, 54 (0.1%) received iMRI, while 37,949 (99.9%) did not receive iMRI. After propensity score matching, the resulting groups consisted of an iMRI group (n = 54) and a matched non-iMRI group (n = 54). Procedures involving iMRI were associated with significantly increased operation length compared to those without (p < 0.01). Length of hospital stay was higher in patients without iMRI, with this difference trending towards significance (p = 0.05) in the unmatched comparison. Patients undergoing craniotomy without iMRI had a higher rate of readmission (p = 0.04). There was no significant difference in occurrence of other adverse events between the two patient groups.

CONCLUSION

Despite increasing operative length, iMRI is not associated with higher infection rate and may have a clinical benefit associated with reducing readmissions and a trend towards reducing inpatient length of stay. Additional nationwide analyses including more iMRI patients would provide further insight into the strength of these findings.

Intraoperative MR Imaging during Glioma Resection

One of the major issues in the surgical treatment of gliomas is the concern about maximizing the extent of resection while minimizing neurological impairment. Thus, surgical planning by carefully observing the relationship between the glioma infiltration area and eloquent area of the connecting fibers is crucial. Neurosurgeons usually detect an eloquent area by functional MRI and identify a connecting fiber by diffusion tensor imaging. However, during surgery, the accuracy of neuronavigation can be decreased due to brain shift, but the positional information may be updated by intraoperative MRI and the next steps can be planned accordingly. In addition, various intraoperative modalities may be used to guide surgery, including neurophysiological monitoring that provides real-time information (e.g., awake surgery, motor-evoked potentials, and sensory evoked potential); photodynamic diagnosis, which can identify high-grade glioma cells; and other imaging techniques that provide anatomical information during the surgery. In this review, we present the historical and current context of the intraoperative MRI and some related approaches for an audience active in the technical, clinical, and research areas of radiology, as well as mention important aspects regarding safety and types of devices.

Comparison of fluorescein sodium, 5-ALA, and intraoperative MRI for resection of high-grade gliomas: A systematic review and network meta-analysis

High grade gliomas (HGGs) are aggressive brain tumors associated with poor prognosis despite advances in surgical treatment and therapy. Navigated tumor resection has yielded improved outcomes for patients. We compare 5-ALA, fluorescein sodium (FS), and intraoperative MRI (IMRI) with no image guidance to determine the best intraoperative navigation method to maximize rates of gross total resection (GTR) and outcomes. A frequentist network meta-analysis was performed following standard PRISMA guidelines (PROSPERO registration CRD42021268659). Surface-under-the-cumulative ranking (SUCRA) analysis was executed to hierarchically rank modalities by the outcomes of interest. Heterogeneity was measured by the I² statistic. Publication bias was assessed by funnel plots and the use of Egger's test. Statistical significance was determined by p < 0.05. Twenty-three studies were included for analysis with a total of 2,643 patients. Network meta-analysis comparing 5-ALA, IMRI, and FS was performed. The primary outcome assessed was the rate of GTR. Analysis revealed the superiority of all intraoperative navigation to control (no navigation). SUCRA analysis revealed the superiority of IMRI + 5-ALA, IMRI alone, followed by FS, and 5-ALA. Overall survival (OS) and progression free survival (PFS) were also examined. FS (vs. control) was associated with improved OS, while IMRI was associated with improved PFS (vs. control, FS, and 5-ALA). Intraoperative navigation using IMRI, FS, and 5-ALA lead to greater rates of GTR in HGGs. FS and 5-ALA also yielded improvement in OS and PFS. Further studies are needed to evaluate differences in survival benefit, operative duration, and cost.

Intraoperative MRI for newly diagnosed supratentorial glioblastoma: a multicenter-registry comparative study to conventional surgery

OBJECTIVE

Intraoperative MRI (iMRI) is used in the surgical treatment of glioblastoma, with uncertain effects on outcomes. The authors evaluated the impact of iMRI on extent of resection (EOR) and overall survival (OS) while controlling for other known and suspected predictors.

METHODS

A multicenter retrospective cohort of 640 adult patients with newly diagnosed supratentorial glioblastoma who underwent resection was evaluated. iMRI was performed in 332/640 cases (51.9%). Reviews of MRI features and tumor volumetric analysis were performed on a subsample of cases (n = 286; 110 non-iMRI, 176 iMRI) from a single institution.

RESULTS

The median age was 60.0 years (mean 58.5 years, range 20.5-86.3 years). The median OS was 17.0 months (95% CI 15.6-18.4 months). Gross-total resection (GTR) was achieved in 403/640 cases (63.0%). Kaplan-Meier analysis of 286 cases with volumetric analysis for EOR (grouped into 100%, 95%-99%, 80%-94%, and 50%-79%) showed longer OS for 100% EOR compared to all other groups (p < 0.01). Additional resection after iMRI was performed in 104/122 cases (85.2%) with initial subtotal resection (STR), leading to a 6.3% mean increase in EOR and a 2.2-cm3 mean decrease in tumor volume. For iMRI cases with volumetric analysis, the GTR rate increased from 54/176 (30.7%) on iMRI to 126/176 (71.5%) postoperatively. The EOR was significantly higher in the iMRI group for intended GTR and STR groups (p = 0.02 and p < 0.01, respectively). Predictors of GTR on multivariate logistic regression included iMRI use and intended GTR. Predictors of shorter OS on multivariate Cox regression included older age, STR, isocitrate dehydrogenase 1 (IDH1) wild type, no O 6-methylguanine DNA methyltransferase (MGMT) methylation, and no Stupp therapy. iMRI was a significant predictor of OS on univariate (HR 0.82, 95% CI 0.69-0.98; p = 0.03) but not multivariate analyses. Use of iMRI was not associated with an increased rate of new permanent neurological deficits.

CONCLUSIONS

GTR increased OS for patients with newly diagnosed glioblastoma after adjusting for other prognostic factors. iMRI increased EOR and GTR rate and was a significant predictor of GTR on multivariate analysis; however, iMRI was not an independent predictor of OS. Additional supporting evidence is needed to determine the clinical benefit of iMRI in the management of glioblastoma.

Applying machine learning to optical coherence tomography images for automated tissue classification in brain metastases

Purpose

A precise resection of the entire tumor tissue during surgery for brain metastases is essential to reduce local recurrence. Conventional intraoperative imaging techniques all have limitations in detecting tumor remnants. Therefore, there is a need for innovative new imaging methods such as optical coherence tomography (OCT). The purpose of this study is to discriminate brain metastases from healthy brain tissue in an ex vivo setting by applying texture analysis and machine learning algorithms for tissue classification to OCT images.

Methods

Tumor and healthy tissue samples were collected during resection of brain metastases. Samples were imaged using OCT. Texture features were extracted from B-scans. Then, a machine learning algorithm using principal component analysis (PCA) and support vector machines (SVM) was applied to the OCT scans for classification. As a gold standard, an experienced pathologist examined the tissue samples histologically and determined the percentage of vital tumor, necrosis and healthy tissue of each sample. A total of 14.336 B-scans from 14 tissue samples were included in the classification analysis.

Results

We were able to discriminate vital tumor from healthy brain tissue with an accuracy of 95.75%. By comparing necrotic tissue and healthy tissue, a classification accuracy of 99.10% was obtained. A generalized classification between brain metastases (vital tumor and necrosis) and healthy tissue was achieved with an accuracy of 96.83%.

Conclusions

An automated classification of brain metastases and healthy brain tissue is feasible using OCT imaging, extracted texture features and machine learning with PCA and SVM. The established approach can prospectively provide the surgeon with additional information about the tissue, thus optimizing the extent of tumor resection and minimizing the risk of local recurrences.

The Neurosurgeon's Armamentarium for Gliomas: An Update on Intraoperative Technologies to Improve Extent of Resection

Maximal safe resection is the standard of care in the neurosurgical treatment of high-grade gliomas. To aid surgeons in the operating room, adjuvant techniques and technologies centered around improving intraoperative visualization of tumor tissue have been developed. In this review, we will discuss the most advanced technologies, specifically fluorescence-guided surgery, intraoperative imaging, neuromonitoring modalities, and microscopic imaging techniques. The goal of these technologies is to improve detection of tumor tissue beyond what conventional microsurgery has permitted. We describe the various advances, the current state of the literature that have tested the utility of the different adjuvants in clinical practice, and future directions for improving intraoperative technologies.

Intraoperative imaging technology to maximise extent of resection for glioma: a network meta-analysis

BACKGROUND

Multiple studies have identified the prognostic relevance of extent of resection in the management of glioma. Different intraoperative technologies have emerged in recent years with unknown comparative efficacy in optimising extent of resection. One previous Cochrane Review provided low- to very low-certainty evidence in single trial analyses and synthesis of results was not possible. The role of intraoperative technology in maximising extent of resection remains uncertain. Due to the multiple complementary technologies available, this research question is amenable to a network meta-analysis methodological approach.

OBJECTIVES

To establish the comparative effectiveness and risk profile of specific intraoperative imaging technologies using a network meta-analysis and to identify cost analyses and economic evaluations as part of a brief economic commentary.

SEARCH METHODS

We searched CENTRAL (2020, Issue 5), MEDLINE via Ovid to May week 2 2020, and Embase via Ovid to 2020 week 20. We performed backward searching of all identified studies. We handsearched two journals, Neuro-oncology and the Journal of Neuro-oncology from 1990 to 2019 including all conference abstracts. Finally, we contacted recognised experts in neuro-oncology to identify any additional eligible studies and acquire information on ongoing randomised controlled trials (RCTs).

SELECTION CRITERIA

RCTs evaluating people of all ages with presumed new or recurrent glial tumours (of any location or histology) from clinical examination and imaging (computed tomography (CT) or magnetic resonance imaging (MRI), or both). Additional imaging modalities (e.g. positron emission tomography, magnetic resonance spectroscopy) were not mandatory. Interventions included fluorescence-guided surgery, intraoperative ultrasound, neuronavigation (with or without additional image processing, e.g. tractography), and intraoperative MRI.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the search results for relevance, undertook critical appraisal according to known guidelines, and extracted data using a prespecified pro forma.

MAIN RESULTS

We identified four RCTs, using different intraoperative imaging technologies: intraoperative magnetic resonance imaging (iMRI) (2 trials, with 58 and 14 participants); fluorescence-guided surgery with 5-aminolevulinic acid (5-ALA) (1 trial, 322 participants); and neuronavigation (1 trial, 45 participants). We identified one ongoing trial assessing iMRI with a planned sample size of 304 participants for which results are expected to be published around winter 2020. We identified no published trials for intraoperative ultrasound. Network meta-analyses or traditional meta-analyses were not appropriate due to absence of homogeneous trials across imaging technologies. Of the included trials, there was notable heterogeneity in tumour location and imaging technologies utilised in control arms. There were significant concerns regarding risk of bias in all the included studies. One trial of iMRI found increased extent of resection (risk ratio (RR) for incomplete resection was 0.13, 95% confidence interval (CI) 0.02 to 0.96; 49 participants; very low-certainty evidence) and one trial of 5-ALA (RR for incomplete resection was 0.55, 95% CI 0.42 to 0.71; 270 participants; low-certainty evidence). The other trial assessing iMRI was stopped early after an unplanned interim analysis including 14 participants; therefore, the trial provided very low-quality evidence. The trial of neuronavigation provided insufficient data to evaluate the effects on extent of resection. Reporting of adverse events was incomplete and suggestive of significant reporting bias (very low-certainty evidence). Overall, the proportion of reported events was low in most trials and, therefore, issues with power to detect differences in outcomes that may or may not have been present. Survival outcomes were not adequately reported, although one trial reported no evidence of improvement in overall survival with 5-ALA (hazard ratio (HR) 0.82, 95% CI 0.62 to 1.07; 270 participants; low-certainty evidence). Data for quality of life were only available for one study and there was significant attrition bias (very low-certainty evidence).

AUTHORS' CONCLUSIONS

Intraoperative imaging technologies, specifically 5-ALA and iMRI, may be of benefit in maximising extent of resection in participants with high-grade glioma. However, this is based on low- to very low-certainty evidence. Therefore, the short- and long-term neurological effects are uncertain. Effects of image-guided surgery on overall survival, progression-free survival, and quality of life are unclear. Network and traditional meta-analyses were not possible due to the identified high risk of bias, heterogeneity, and small trials included in this review. A brief economic commentary found limited economic evidence for the equivocal use of iMRI compared with conventional surgery. In terms of costs, one non-systematic review of economic studies suggested that, compared with standard surgery, use of image-guided surgery has an uncertain effect on costs and that 5-ALA was more costly. Further research, including completion of ongoing trials of ultrasound-guided surgery, is needed.

Resection and survival data from a clinical trial of glioblastoma multiforme-specific IRDye800-BBN fluorescence-guided surgery

Supra-maximum surgical tumor resection without neurological damage is highly valuable for treatment and prognosis of patients with glioblastoma multiforme (GBM). We developed a GBM-specific fluorescence probe using IRDye800CW (peak absorption/emission, 778/795 nm) and bombesin (BBN), which (IRDye800-BBN) targets the gastrin-releasing peptide receptor, and evaluated the image-guided resection efficiency, sensitivity, specificity, and survivability. Twenty-nine patients with newly diagnosed GBM were enrolled. Sixteen hours preoperatively, IRDye800-BBN (1 mg in 20 ml sterile water) was intravenously administered. A customized fluorescence surgical navigation system was used intraoperatively. Postoperatively, enhanced magnetic resonance images were used to assess the residual tumor volume, calculate the resection extent, and confirm whether complete resection was achieved. Tumor tissues and nonfluorescent brain tissue in adjacent noneloquent boundary areas were harvested and assessed for diagnostic accuracy. Complete resection was achieved in 82.76% of patients. The median extent of resection was 100% (range, 90.6-100%). Eighty-nine samples were harvested, including 70 fluorescence-positive and 19 fluorescence-negative samples. The sensitivity and specificity of IRDye800-BBN were 94.44% (95% CI, 85.65-98.21%) and 88.24% (95% CI, 62.25-97.94%), respectively. Twenty-five patients were followed up (median, 13.5 [3.1-36.0] months), and 14 had died. The mean preoperative and immediate and 6-month postoperative Karnofsky performance scores were 77.9 ± 11.8, 71.3 ± 19.2, and 82.6 ± 14.7, respectively. The median overall and progression-free survival were 23.1 and 14.1 months, respectively. In conclusion, GBM-specific fluorescent IRDye800-BBN can help neurosurgeons identify the tumor boundary with sensitivity and specificity, and may improve survival outcomes.

Cost-Effectiveness of Intraoperative CT Scanning in Cochlear Implantation in Fee-for-Service and Bundled Payment Models

OBJECTIVE

Electrode array tip fold-over is a complication of cochlear implant surgery that results in poor hearing outcomes and often leads to revision surgery. However, tip fold-over can be corrected immediately if identified through intraoperative computed tomography, which also potentially provides information about final intracochlear positioning. Our objective was to provide the first economic analysis of intraoperative computed tomography by generating models in fee-for-service and bundled payment reimbursement structures of payer and institutional cost-effectiveness of this technology used in cochlear implantation over 1, 5, and 10-year time periods.

METHODS

Cost data specific to a commerically available intraoperative computed tomography machine was obtained from the manufacturer, Xoran Technologies. Institutional tip fold-over rate was obtained from already published data. Medicare reimbursement rate for cochlear implantation was obtained from institutional accountants. Private payer reimbursement for and cost of revision cochlear implantation were estimated based on available data.

RESULTS AND CONCLUSION

At large volume centers, cost-effectiveness of this technology is possible in both fee-for-service and bundled payment reimbursement structures at various time points dependent on payer mix. Even low volume cochlear implantation centers (<150 per year) can financially benefit from intraoperative computed tomography in bundled payment models at 5- and 10-year periods regardless of payer mix. This model demonstrates key factors at play in determining cost-effectiveness of this technology including institutional factors and payer type and suggests this technology can align incentives both to improve patient care and outcomes with institutional and payer financial well-being.