Predictors for spinal deformity following resection of intramedullary tumor via posterior approach: a systematic review and meta-analysis.

PURPOSE: The present study aimed to identify the clinical predictive factors for worsened spinal deformity (SD) following surgical resection via posterior approach for primary intramedullary tumors. METHODS: A systematic search was performed using PubMed, Web of Science, and Scopus databases to extract potential references. Observational studies reporting predictive factors for worsened SD following surgical resection via posterior approach for primary intramedullary tumors were included. The odds ratio (OR) was calculated for dichotomous parameters. RESULTS: Four retrospective cohort studies were included in the meta-analysis. They were comprised of two groups of patients; those who developed SD (n = 87) and those who did not (n = 227). For patients with IMSCTs, age under 25 years as well as age under 13 years were the demographic variables associated with postoperative SD (odds ratio [OR] 3.92; p = 0.0002 and OR 4.22; p = 0.003). In both the fusion and the non-fusion subgroups, preoperative spinal deformity strongly predicted postoperative SD (OR 11.94; p < 0.001), with the risk highly elevated among the non-fusion patients (OR 24.64; p < 0.0002). Thoracolumbar junction involvement was also found to be a predictor of postoperative SD for patients with IMSCT (OR 2.89; p = 0.02). CONCLUSION: This study highlights the importance of considering age, preoperative spinal deformity, and thoracolumbar junction involvement as predictors of postoperative spinal deformity following surgical resection for IMSCT. These findings may provide guidance for the management of these patients, including the development of preoperative planning strategies and the selection of the most appropriate surgical approach for high-risk patients.

Impact of COVID-19 on incidence and treatment of intracranial aneurysms in Poland: a national study.

INTRODUCTION: The COVID-19 pandemic greatly disrupted the national healthcare system in Poland, resulting in the implementation of new protocols allowing only patients with severe diagnoses to receive immediate treatment. Given that an intracranial aneurysm (IA) is regarded as one of the most severe diagnoses, we planned to assess whether the current protocol has successfully provided the standard treatment for IAs. MATERIAL AND METHODS: Data on all IA cases treated from 2015 to 2020 was extracted from the JGP (a homogeneous group of patients) catalogue provided by the National Health Index of Poland (NFZ, Narodowy Fundusz Zdrowia). Poisson regression was used to determine the significance of the change in hospital admissions, and differences between proportions were analysed using the "N-1" Chi-squared test. RESULTS: A total of 21,801 IA patients treated during 2015-2020 were included in this study. The overall number of hospitalisations due to IAs fell in the open surgery group, but not in the endovascular cohort. Mortality rates following IA treatment increased significantly by 21% in 2020 compared to preceding years. The demographics changed as well; the patients were significantly younger during the pandemic. CONCLUSIONS: Our findings show that the current strategy for optimal care for patients diagnosed with IAs in Poland during the pandemic is failing to maintain high quality treatment. New methods to improve the current plan should be implemented to address future crises.

Association of long-term outcome of long cervical fusion with sagittal balance: the significance of T1 slope minus cervical lordosis.

INTRODUCTION: Retrospective study to assess correlation between the sagittal alignment of the cervical spine and the long-term outcomes of long cervical fusion due to cervical spondylotic myelopathy (CSM), with the emphasis on T1 slope minus cervical lordosis (T1S-CL). SUMMARY OF BACKGROUND DATA: Growing evidence shows that the sagittal profile can play a major role in the outcomes of treatment, but the role of its correction is yet to be established. MATERIAL AND METHODS: We conducted a retrospective analysis of 54 patients treated for CSM from 2006 to 2012. The neck pain-related disability was measured using NDI, the myelopathy was measured with the mJOA and Nurick scales. Six years after the surgery, standardised X-ray measurements were obtained, including C2-C7 lordosis (CL), C2-C7 sagittal vertical alignment (SVAC2-C7), T1 slope (T1S), and T1S minus CL (T1S-CL). The patients were divided based on the T1S-CL into two groups, using the threshold value of 16.5 degrees. RESULTS: A statistically significant improvement was noted in the mean NDI, mJOA, and median Nurick scale during the initial two years in both groups. The better aligned group had a better outcome measured with NDI at all follow-ups. The mJOA was significantly better in the better aligned group, but only preoperatively; at all follow-ups, the difference was not significant. T1S-CL had the strongest correlation with the NDI at the final follow-up. CONCLUSIONS: T1S-CL is an effective prognostic factor of the long term outcome after long cervical fusion in CSM treatment.

YouTube as a source of information for narcolepsy: A content-quality and optimization analysis.

YouTube is the world's most popular video-sharing site that in recent years has become an important platform for patients in finding educational information about their disease. The purpose of this study was to assess the quality and reliability of narcolepsy-related YouTube videos. We searched the key terms "Narcolepsy", "Narcolepsy-cataplexy," "Narcolepsy excessive daytime sleepiness" and "Narcolepsy excessive drowsiness" on YouTube. 80 videos were analyzed as they meet the inclusion criteria. Quantitative and qualitative metrics were recorded and the videos were scored using the DISCERN instrument by two independent raters. Our findings show that the majority of videos contained clear information (84%), symptoms (78%) and patient experience (69%). Most videos were published by an educational channel not representing a hospital or clinic (41%) or by a patient suffering from the disease (25%). Videos containing animations had a statistically significant correlation between average daily views (p = .0004) and the video power index (p = .0048), suggesting that this feature increased the popularity among viewers. The mean DISCERN score was 27 ± 8, indicating that the quality of narcolepsy related-videos is poor. Therefore, patients that use YouTube as an educational tool are currently not attaining a comprehensive understanding of the disease. For this reason, we have indicated the top 5 videos that physicians can recommend to their patients. Our paper highlights the gaps of knowledge concerning narcolepsy information on YouTube. Therefore, this information can be used to create better educational content in the future.

YouTube as a source of patient information for Coronavirus Disease (COVID-19): A content-quality and audience engagement analysis.

YouTube is the second most popular website in the world and is increasingly being used as a platform for disseminating health information. Our aim was to evaluate the content-quality and audience engagement of YouTube videos pertaining to the SARS (severe acute respiratory syndrome)-CoV-2 virus which causes the Coronavirus Disease 2019 (COVID-19), during the early phase of the pandemic. We chose the first 30 videos for seven different search phrases: "2019 nCoV," "SARS CoV-2," "COVID-19 virus," "coronavirus treatment," "coronavirus explained," "what is the coronavirus" and "coronavirus information." Video contents were evaluated by two independent medical students with more than 5 years of experience using the DISCERN instrument. Qualitative data, quantitative data and upload source for each video was noted for a quality and audience engagement analysis. Out of the total 210 videos, 137 met our inclusion criteria and were evaluated. The mean DISCERN score was 31.33 out of 75 possible points, which indicates that the quality of YouTube videos on COVID-19 is currently poor. There was excellent reliability between the two raters (intraclass correlation coefficient = 0.96). 55% of the videos discussed prevention, 49% discussed symptoms and 46% discussed the spread of the virus. Most of the videos were uploaded by news channels (50%) and education channels (40%). The quality of YouTube videos on SARS-CoV-2 and COVID-19 is poor, however, we have listed the top-quality videos in our article as they may be effective tools for patient education during the pandemic.

YouTube as a source of patient information on brain aneurysms: a content-quality and audience engagement analysis.

INTRODUCTION: The internet allows patients to access a vast amount of health information. We aimed to evaluate the credibility of YouTube videos that members of the public are accessing on brain aneurysms, and to evaluate what characteristics drive audience engagement. MATERIAL AND METHODS: The first 50 videos for each of the following search terms were taken for analysis: 'brain aneurysm', 'cerebral aneurysm' and 'intracranial aneurysm'. The quality of each video was evaluated by two neurosurgeons and two medical students independently using the Journal of the American Medical Association (JAMA) and the DISCERN instruments. Qualitative and quantitative video data was analysed for quality and audience engagement. Inter-rater agreement was ascertained. RESULTS: Out of a total of 150 videos, 70 met the inclusion criteria. The mean total DISCERN score was 36.5 ± 8.4 (out of 75 points), indicating that the videos were of poor quality. The mean JAMA score was 2.7 ± 0.7 (out of 4 points). Inter-rater agreement between the four raters was excellent (intraclass correlation coefficient 0.90 for DISCERN and 0.93 for JAMA). Most videos were uploaded by hospitals (50%) or educational health channels (30%). Videos had a higher number of average daily views when they included animation (P = 0.0093) and diagrams (P = 0.0422). CONCLUSIONS: YouTube is a poor source of patient information on brain aneurysms. Our quality and audience engagement analysis may help content creators (i.e. hospital staff and physicians) to create more holistic, educational and engaging medical videos concerning brain aneurysms. Physicians could usefully refer their patients to the highest quality videos that we have found.

Can sectioning the posterior communicating artery be predicted with computed tomography angiography in the microsurgical clipping of basilar apex aneurysms?

BACKGROUND: Microsurgical clipping is a viable option for managing high-riding basilar apex aneurysms (BAXs) using a transsylvian approach. Cutting the posterior communicating artery (PCoA) at the perforator-free zone provides sufficient exposure of BAX, although it is not always safe. The aim was to qualitatively predict sectioning of the interfering PCoA by using preoperative computed tomographic angiography (CTA). METHODS: A virtual trajectory from the lesser sphenoid wing to the neck of the aneurysm was simulated on CTA in 19 consecutive patients operated on BAX aneurysms from 2013 to 2018. The angles on CTA resembled the typical view through the extended pterional craniotomy. Next, the ipsilateral PCoA was tracked from the internal carotid to its end at the posterior cerebral artery in the trajectory. RESULTS: The opticocarotid and carotid-oculomotor window served as the corridors for entering the interpeduncular fossa in 16 patients (84.2%) and in 3 patients (15.8%), respectively. The PCoA was intentionally cut during nine surgeries and preserved in 10 of them. The PCoA was cut more often when positioned toward the cranial base and more medially in the corridor; both the Kernel density analysis and the data points representing the position of the PCoA supported this finding (p < 0.01). The CTA-based position of either ends of the PCoA in the trajectory did not differ between cut and not-cut groups (p = 0.19-0.96). Aneurysm projection, rupture, size, PCoA diameter, length, and other distances on CTA were not related to the sectioning of PCoA (p > 0.05). CONCLUSIONS: The probability of PCoA sectioning is higher when the PCoA is positioned medially and closer to the cranial base. If the anatomical course of the PCoA is recognized beforehand, it can contraindicate surgery. Preoperative CTA-based planning facilitates the surgery of BAX aneurysms. Therefore, CTA can make microsurgical clipping planning more predictable for the neurosurgeon and safer for the patient.

Does Spinal Cord Stimulation Due to Failed Back Surgery Syndrome Lead to Permanent Occupational Disability?

OBJECTIVE: Spinal cord stimulation (SCS) is a recommended treatment method for patients afflicted by failed back surgery syndrome (FBSS). Although SCS is shown to be clinically effective, not many patients return to work (RTW). The aim of this study is to assess the RTW rate of these patients. MATERIALS AND METHODS: We prospectively evaluated 102 patients with FBSS, managed by low frequency SCS at a single institution in Poland. RTW rate was the main endpoint in the study. Additionally, we browsed the first 300 records in Google and extracted the suggested RTW time post-SCS implantation. RESULTS: Mean follow-up was 8.5 years. 79.4% of patients were actively working at the baseline. Fifteen patients were sick leave benefit claimants (15/81; 18.5%) and six were permanently disabled (6/81; 7.4%). In the follow-up, 40 did not change their work status. Only 2 of 21 patients resumed work and the total RTW rate was 9.5%. On the other hand, 38 of 81 patients (46.9%), who actively worked before SCS, gained disability status. Out of entire group, 20.6% (21 of 102) were not working at the baseline and 55.9% (57 of 102) were not working in the follow-up. Neither factor influenced RTW rate. In the second stage of the study, internet data search yielded a mean RTW time of 6.1 weeks. CONCLUSIONS: Unlike the well-analyzed effectiveness of SCS, RTW remains an underutilized outcome measure. The RTW rate in our series was the second lowest in the reviewed literature. We demonstrated that half of the patients with an implanted SCS either did not resume their work or left their job.

YouTube as a source of patient information for stroke: A content-quality and an audience engagement analysis.

BACKGROUND: Stroke is the second leading cause of death worldwide following ischemic heart disease, and the fifth in the United States. The video-sharing database, YouTube, is the second most popular visited website with more than 2 billion users, thus it's increasingly being used as a medium for delivering health information. AIM: We aimed to evaluate the quality, reliability and audience engagement of stroke-related YouTube videos. METHODS: In October 2019 we conducted a search on YouTube using 5 keywords: stroke, brain attack, hemorrhagic stroke, ischemic stroke and transient ischemic attack. We selected the first 30 videos from each search query for further analysis. The validated DISCERN instrument was used (a score of 0-5 per question) to assess the videos by four independent raters. We then recorded qualitative data and quantitative data for each video. RESULTS: After sorting through 150 stroke videos, a total of 101 unique YouTube videos met our inclusion criteria. We found that the mean overall quality of YouTube videos according to DISCERN is of fair quality. Most videos (65.3%) were uploaded by hospitals, mentioned the symptoms of stroke (66.3%), had a doctor speaking (60.4%) and contained diagrams (20.8%). CONCLUSION: YouTube is a useful source of gathering information about treatment choices for patients and their families as the quality of YouTube videos is fair. The audience engagement suggestions in our paper may help content creators improve the appeal of YouTube videos.

Extent of anterior clinoidectomy for clipping of carotid-ophthalmic aneurysms predicted on three-dimensional computerised tomography angiography.

AIM OF STUDY: We aimed to verify the value of computerised tomography angiography (CTA) on predicting the extent of anterior clinoidectomy that is optimal for particular carotid-ophthalmic aneurysms (COAs). CLINICAL RATIONALE FOR STUDY: The anterior clinoid process (ACP) often impedes the complex microsurgery of COA. Complete removal of the ACP ensures safe clipping; however, it also may increase the risk of severe complications. The probability of performing a successful partial anterior clinoidectomy could be evaluated by preoperative CTA. MATERIALS AND METHODS: 28 patients with either a ruptured (n=4) or unruptured COA were included in this prospective, single-centre, observational study. One aneurysm was giant, two were large, and the rest were smaller. Successful aneurysm clipping was the aim in all cases. The anterior clinoidectomy was preoperatively planned on multiplanar three-dimensional reconstructions of CTA images (3D-CTA) which resembled the typical view of a frontotemporal craniotomy. Finally, the predicted clinoidectomy was compared to the extent of the actual clinoidectomy. RESULTS: 21 aneurysms (75%) projected superolateral or superior. The ACP was completely and selectively resected in 25% (7 of 28) and 67.9% of patients (19 of 28) respectively. Optic nerve (ON) unroofing was always performed in the case of total anterior clinoidectomy, but accompanied only 8 of 19 selective clinoidectomies (p = 0.03). The extent of the actual clinoidectomy was predicted by the 3D-CTA-based preoperative planning in 17 of 27 cases (63.0%). Particularly, prediction of the osteotomy was correct in 85.7% of complete, 62.5% of selective lateral, and 57.1% of medial clinoidectomy. None of the radiological and clinical factors determined the correlation between the planned and the actual extent of ACP removal. There was one incomplete occlusion among 23 obtained follow-up CTAs. CONCLUSIONS: The predictive value of 3D-CTA on the extent of anterior clinoidectomy still remains unsatisfactory; it is limited by the individual variability of COA and its surrounding structures. CLINICAL IMPLICATIONS: Currently, the role of 3D-CTA planning is restricted to educational purposes only.

Reliability of diffusion tensor tractography of facial nerve in cerebello-pontine angle tumours.

AIM OF THE STUDY: This study aimed to verify the accuracy of preoperative visualisation of the facial nerve (FN) by magnetic resonance-based (MR) diffusion tensor imaging-fibre tracking (DTI-FT) with neuronavigation system integration in patients with cerebello-pontine angle (CPA) tumours. CLINICAL RATIONALE FOR THE STUDY: Complete excision with preservation of the FN remains the critical goal of today's vestibular schwannoma (VS) surgery. DTI-FT of the FN with neuronavigation is yet to be fully evaluated, and could make surgery safer. MATERIALS AND METHODS: This was a prospective cohort study in which 38 consecutive patients with a CPA tumour (32 VSs, five meningiomas and one epidermoid cyst) were operated on via the retrosigmoid route from 2013 to 2019. The course of the FN was simulated before surgery using StealthViz and the images were transferred to the Medtronic S7 neuronavigation system. The FN location reconstructed by DTI-FT was verified during the surgery. RESULTS: MR acquisition was inappropriate in three patients (7.9%). DTI-FT correctly predicted the course of the FN in 31 of the 38 patients; the discordance rate was 18.4%. The accuracy of DTI-FT was 81.6% (95% CI: 65.67-92.26), sensitivity 88.57% (95% CI: 73.26-96.80) and positive predictive value was 91.18% (95% CI: 90.17-92.09). The reliability of the neuronavigation-integrated visualisation of the FN did not depend on the tumour size (p = 0.85), but the method was more accurate when the nerve was compact in shape (p = 0.03, area under curve (AUC) 0.87, 95% CI: 0.60-1.00) and in females (p = 0.04, AUC 0.78, 95% CI: 0.56-1.00). Following surgery, 86.5% of the patients presented with useful facial function (House-Brackmann grades I-III). Correct simulation of the FN did not prevent postoperative facial palsy (p = 0.35). CONCLUSIONS: The accuracy of DTI-FT of the FN integrated with neuronavigation remains unsatisfactory. This method does not provide any clinical benefit over non-integrated DTI-FT in terms of nerve function preservation. CLINICAL IMPLICATIONS: Due to the low reliability of the predictions, further technical advances in predicting the course of the FN are awaited by clinicians. However, DTI-FT images in the operating theatre would make tumour excision more comfortable for the surgeon.

Morphometric Analysis of the Lumbar Vertebrae Concerning the Optimal Screw Selection for Transpedicular Stabilization.

Transpedicular stabilization is a frequently used spinal surgery for fractures, degenerative changes, or neoplastic processes. Improper screw fixation may cause substantial vascular or neurological complications. This study seeks to define detailed morphometric measurements of the pedicle (height, width, and surface area) in the aspects of screw length and girth selection and the trajectory of its implantation, i.e., sagittal and transverse angle of placement. The study was based on CT examinations of 100 Caucasian patients (51 women and 49 men) aged 27-75 with no anatomical, degenerative, or post-traumatic spine changes. The results were stratified by gender and body side, and they were counter compared with the available literature database. Pedicle height decreased from L1 to L4, ranging from 15.9 to 13.3 mm. Pedicle width increased from L1 to L5, extending from 6.1 to 13.2 mm. Pedicle surface area increased from L1 to L5, ranging from 63 to 140 mm2. Distance from the point of entry into the pedicle to the anterior surface of the vertebral body, defining the maximum length of a transpedicular screw, varied from 54.0 to 50.2 mm. Variations concerning body sides were inappreciable. A transverse angle of screw trajectory extended from 20° to 32°, shifting caudally from L1 to L5, with statistical differences in the L3-L5 segments. A sagittal angle varied from 10° to 12°, without such definite relations. We conclude that the L1 and L2 segments display the most distinct morphometric similarities, while the greatest differences, in both genders, are noted for L3, L4, and L5. The findings enable the recommendation of the following screw diameters: 4 mm for L1-L2, 5 mm for L3, 6 mm for L4-L5, and the length of 50 mm. We believe the study has extended clinical knowledge on lumbar spine morphometry, essential in the training physicians engaged in transpedicular stabilization.

The "Optimum Volume" of Acrylic Cement Filling for Treating Vertebral Compression Fractures: A Morphometric Study of Thoracolumbar Vertebrae.

Percutaneous vertebroplasty is a treatment option in vertebral compression fractures (VCF). The aim of the study was to propose the mathematical calculation of the "optimum volume" of acrylic cement filling of the vertebral body, depending on the severity of a fracture. Two hundred computed tomography (CT) scans of vertebral columns in healthy adult Caucasians were analyzed. Vertebral body width (VBW), vertebral body depth (VBD), vertebral body height (VBH), and vertebral body volume (VBV) were measured. The "optimum volume" of cement injections in mild (25% collapse) and moderate (40% collapse) VCF were calculated. We found that moving caudally from Th11 to L2, the mean values of the examined parameters increased: VBH from 22.6 to 26.0 mm, VBW from 34.0 to 39.5 mm, VBD from 28.1 to 30.9 mm, and VBV from 17.1 to 24.8 cm3. The calculated hypothetical "optimum volume" of cement injection increased from 7.4 to 10.0 cm3 in mild VCF and from 5.9 to 7.8 cm3 in moderate VCF, with some variability depending on the vertebral level and gender. These values are akin to those present in other past studies. We conclude that morphometric measurements, based on CT images, are a reliable source of practical anatomical savvy, which may be of help in spine surgery.

Neurosurgery residency burnout: what can prevent this?

Burnout is an occupational phenomenon indicating that the work and the workplace are responsible. We here discuss how a supportive resident-mentor relationship, and a positive working environment, could help to prevent resident burnout. A positive resident-mentor relationship can be achieved by understanding the mentor, the mentee, and the generational differences of each individual. A positive working environment depends on a healthy work-life balance and the atmosphere in the department. The benefits of preventing burnout include not only happier physicians but also fewer medical errors and better medical care. The universal reminders and proven suggestions in our paper could help address the burnout problem among working physicians worldwide.

The molecular pattern of histopathological progression to anaplastic meningioma - A case report.

Meningiomas (MGs) are the most frequent primary tumours of the central nervous system (CNS) and exhibit a large spectrum of histological types and clinical phenotypes. The WHO classification of CNS tumours established strict diagnostic criteria of the benign (Grade 1), atypical (Grade 2) and anaplastic (Grade 3) subtypes. Combined with the resection rate, WHO grading has the most crucial role as the prognostic factor. Additionally, such biomarkers as Ki-67/MIB-1, progesterone receptors and phosphor-histone H3 were correlated with MG progression. Recently, it was suggested that the aggressive behaviour of some MGs is attributed to molecular alterations, regardless of their histopathology. The analysis of loss of heterozygosity (LOH) at chromosomes 1, 9, 10, 14 and 22 was performed. The presented case of WHO Grade 2 MG initially exhibited LOH at chromosomes 10, 14 and 22. In the first recurrence, the tumour genetic profiling revealed additional LOH at chromosome 1p and atypical histopathology. During the second recurrence, an aggressive phenotype was observed and tumour progressed to an anaplastic form. Considering the appearance of the tumour relapses, the set of molecular changes overtook the histopathological progression. The genetic and histopathological imbalance in the tumour progression in secondary anaplastic MGs has not been previously described. The evolution of genetic and histopathological changes was presented in the same patient. In the future, the individualised therapy of potentially more aggressive forms of MGs could be based on certain chromosome aberrations.

Diffusion tensor tractography imaging in pediatric epilepsy - A systematic review.

PURPOSE: Recent years brought several experimental and clinical reports applying diffusion tensor tractography imaging (DTI) of the brain in epilepsy. This study was aimed to evaluate current evidence for adding the DTI sequence to the standard diagnostic magnetic resonance imaging (MRI) protocol in pediatric epilepsy. MATERIAL AND METHODS: Rapid and qualitative systematic review (RAE, Rapid Evidence Assessment), aggregating relevant studies from the recent 7 years. The PubMed database was hand searched for records containing terms "tractography AND epilepsy." Only studies referring to children were included; studies were rated using "final quality of evidence." RESULTS: Out of 144 screened records, relevant 101 were aggregated and reviewed. The synthesis was based on 73 studies. Case-control clinical studies were the majority of the material and comprised 43.8% of the material. Low 'confirmability' and low 'applicability' referred to 18 and 17 articles (29.5% and 27.9%), respectively. The sufficient quality of evidence supported performing DTI in temporal lobe epilepsy, malformations of cortical development and prior to a neurosurgery of epilepsy. CONCLUSIONS: The qualitative RAE provides an interim estimate of the clinical relevance of quickly developing diagnostic methods. Based on the critical appraisal of current knowledge, adding the DTI sequence to the standard MRI protocol may be clinically beneficial in selected patient groups with childhood temporal lobe epilepsy or as a part of planning for an epilepsy surgery.

Recurrence-associated chromosomal anomalies in meningiomas: Single-institution study and a systematic review with meta-analysis.

Complete removal of a meningioma (MG) does not guarantee relapse-free survival. Alterations on several chromosomes responsible for MG recurrence were suggested, although their role was not validated by a systematic review. Following the analysis of own 161 cases, all previously published data has been collected for evidence synthesis. Based on own series, WHO grade >I (odds ratio (OR)=92.0; 95%CI: 19.1-443.5) and a combination of loss of heterozygosity (LOH) on 1p and 14q (OR=10.2; 95%CI: 19-55.7) were the independent recurrence-specific prognosticators. The deleterious role of LOH on 1p/14q was demonstrated in a subset of parasagittal and falcine MGs. A total of 742 cases and 10 studies were pooled for the Individual Patient Data and Aggregate Data models of meta-analysis, respectively. The prognostic role of WHO classification (OR=90.4) and anomaly of chromosome 14 (OR=3.5) was confirmed. LOH on 14 showed lesser impact on recurrence than suggested by the WHO grading (area under the curve 0.65 for LOH vs. 0.74 for WHO). Fixed effect model of meta-analysis provided high summarized OR values for 1p (OR=5.4; 95%CI: 3.6-8.1) and 14q (OR=7.6; 95%CI: 4.3-13.6), and low for chromosome 22 (OR=1.6; 95%CI: 1.1-2.4). Final appraisal of recurrence-associated chromosomal alterations indicated that arms 1p and 14q deserve attention while predicting MG recurrence.

The correlation of clinical and chromosomal alterations of benign meningiomas and their recurrences.

Meningiomas (MGs) are the frequent benign intracranial tumors. Their complete removal does not always guarantee relapse-free survival. Recurrence-associated chromosomal anomalies in MGs haves been proposed as prognostic factors in addition to the World Health Organisation (WHO) grading, tumor size and resection rate. The aim of this study was to evaluate the frequency of deletions on chromosomes in sporadic MGs and to correlate them with the clinical findings and tumor behaviour. Along with survival, the tumor recurrence was the main endpoint. Chromosomal loss of heterozygosity (LOH) was studied. 46 benign MGs were subjected to the analysis, complete tumor resection was intended and no early mortalities were observed. Incomplete removal was related to parasagittal location and psammomatous hisptopathology (p<0.01). Chromosomal alterations were present in 82.6% of cases; LOH at 22q (67.4%) and 1p (34.8%) were the most frequent and associated with male sex (p=0.04). Molecular findings were not specific for any of the histopathologic grade. Tumor recurrence (14 of 46) correlated with tumor size (≥35mm), LOH at 1p, 14q, coexistence of LOH at 1p/14q, 10q/14q, 'complex karyotype' status (≥2 LOHs excluding 22q), patient age (younger <35), and Simpson grading of resection rate (≥3 of worse prognosis). The last 3 variables were independent significant prognostic factors in multivariate analysis and of the same importance in recurrence prediction (Receiver Operating Characteristic curves comparison p>0.05). Among the cases of recurrence, tumor progression was observed in 3 of 14. In 2 cases, LOH on 1p and/or coexistence of LOH 1p/14q correlated with anaplastic transformation.

Colour contrasting between tissues predicts the resection in 5-aminolevulinic acid-guided surgery of malignant gliomas.

Due to the various intensities of 5-aminolevulinic acid (5-ALA) fluorescence, neurosurgeons tend to be uncertain about which tissues to resect. This study aimed to reveal the shortcomings of the human visual perception of fluorescence, particularly the factors guiding the tissue removal and the correlation of fluorescence with contrast enhancement (CE) on magnetic resonance imaging (MRI). Various colour features [CIE L*a*b* colour space, colour difference described by ΔE and contrast ratio (CR)] of total 206 noticed fluorescent areas and their surroundings were measured from the video recordings of 21 primary high grade glioma (HGG) surgeries. The position of a fluorescent region was related to the corecorded navigational image. Following early postoperative MRI, 17 additional regions of corresponding to CE remnants were identified, their colour features were compared to the resected CEs. The targeted video post-processing method was designed, based on the results. There were no complications attributed to 5-ALA use and the median survival was <10 months. 82.5 % of recognised fluorescent areas were removed. Colour spaces of the resected regions and their backgrounds did not overlap. Opposite to the separate colour components (p > 0.05), the distant background colour (p < 0.05) and higher CR and ΔE (p < 0.01) determined the resection of a fluorescent region. Noneloquent location and CR both independently increased the resection rate in logistic regression. However, greater area under the receiver operating characteristic curve (AUC) in case of CR (AUC = 0.78; 95 % CI 0.71-0.83) determined its dominant role in neurosurgeon's fluorescence perception. CE regions presented with a significantly more saturated shade of violet (consistently higher a* and b*) than other tumour parts (p < 0.05). Regions corresponding to tumour remnants had a significantly lower a* component value (p = 0.02) as well as a lower ΔE than the matched background (AUC = 0.73; 95 % CI 0.65-0.80). In order to increase the resection rate, ΔE > 60 was needed. These results directed essential improvements in the 5-ALA fluorescence visualisation toward enhanced resection rate. The conventional filtering, unadjusted to the 5-ALA colour space converted some background shades to colours resembling relevant fluorescence. This is one of the first studies to demonstrate that perceived colours, their contrasting and CR are of significance in the decision-making during HGG 5-ALA fluorescence-guided surgery. Irrespective of the shortcomings of conventional video filtering, further development of a tailored post-processed contrast stretching will allow to achieve safe and radical tumour resection.