Generation and applications of synthetic computed tomography images for neurosurgical planning.

OBJECTIVE: CT and MRI are synergistic in the information provided for neurosurgical planning. While obtaining both types of images lends unique data from each, doing so adds to cost and exposes patients to additional ionizing radiation after MRI has been performed. Cross-modal synthesis of high-resolution CT images from MRI sequences offers an appealing solution. The authors therefore sought to develop a deep learning conditional generative adversarial network (cGAN) which performs this synthesis. METHODS: Preoperative paired CT and contrast-enhanced MR images were collected for patients with meningioma, pituitary tumor, vestibular schwannoma, and cerebrovascular disease. CT and MR images were denoised, field corrected, and coregistered. MR images were fed to a cGAN that exported a "synthetic" CT scan. The accuracy of synthetic CT images was assessed objectively using the quantitative similarity metrics as well as by clinical features such as sella and internal auditory canal (IAC) dimensions and mastoid/clinoid/sphenoid aeration. RESULTS: A total of 92,981 paired CT/MR images obtained in 80 patients were used for training/testing, and 10,068 paired images from 10 patients were used for external validation. Synthetic CT images reconstructed the bony skull base and convexity with relatively high accuracy. Measurements of the sella and IAC showed a median relative error between synthetic CT scans and ground truth images of 6%, with greater variability in IAC reconstruction compared with the sella. Aerations in the mastoid, clinoid, and sphenoid regions were generally captured, although there was heterogeneity in finer air cell septations. Performance varied based on pathology studied, with the highest limitation observed in evaluating meningiomas with intratumoral calcifications or calvarial invasion. CONCLUSIONS: The generation of high-resolution CT scans from MR images through cGAN offers promise for a wide range of applications in cranial and spinal neurosurgery, especially as an adjunct for preoperative evaluation. Optimizing cGAN performance on specific anatomical regions may increase its clinical viability.

Strategies to improve surgical technical competency: a systematic review.

BACKGROUND: A cornerstone of surgical residency training is an educational program that produces highly skilled and effective surgeons. Training structures are constantly being revised due to evolving program structures, shifting workforces, and variability in the clinical environment. This has resulted in significant heterogeneity in all surgical resident education, training tools utilized, and measures of training efficacy. METHODS: We systematically reviewed educational interventions for technical skills in neurosurgery published across PubMed, Embase, and Web of Science over four decades. We extracted general characteristics of each surgical training tool while categorizing educational interventions by modality and neurosurgical application. RESULTS: We identified 626 studies which developed surgical training tools across eight different training modalities: textbooks and literature (11), online resources (53), didactic teaching and one-on-one instruction (7), laboratory courses (50), cadaveric models (63), animal models (47), mixed reality (166), and physical models (229). While publication volume has grown exponentially, a majority of studies were cited with relatively low frequency. Most training programs were published in the development and validation phase with only 2.1% of tools implemented long-term. Each training modality expressed unique strengths and limitations, with limited data reported on the educational impact connected to each training tool. CONCLUSIONS: Numerous surgical training tools have been developed and implemented across residency training programs. Though many creative and cutting-edge tools have been devised, evidence supporting educational efficacy and long-term application is lacking. Increased utilization of novel surgical training tools will require validation of metrics used to assess the training outcomes and optimized integration with clinical practice.

Advances and Evolving Challenges in Spinal Deformity Surgery.

BACKGROUND: Surgical intervention is a critical tool to address adult spinal deformity (ASD). Given the evolution of spinal surgical techniques, we sought to characterize developments in ASD correction and barriers impacting clinical outcomes. METHODS: We conducted a literature review utilizing PubMed, Embase, Web of Science, and Google Scholar to examine advances in ASD surgical correction and ongoing challenges from patient and clinician perspectives. ASD procedures were examined across pre-, intra-, and post-operative phases. RESULTS: Several factors influence the effectiveness of ASD correction. Standardized radiographic parameters and three-dimensional modeling have been used to guide operative planning. Complex minimally invasive procedures, targeted corrections, and staged procedures can tailor surgical approaches while minimizing operative time. Further, improvements in osteotomy technique, intraoperative navigation, and enhanced hardware have increased patient safety. However, challenges remain. Variability in patient selection and deformity undercorrection have resulted in heterogenous clinical responses. Surgical complications, including blood loss, infection, hardware failure, proximal junction kyphosis/failure, and pseudarthroses, pose barriers. Although minimally invasive approaches are being utilized more often, clinical validation is needed. CONCLUSIONS: The growing prevalence of ASD requires surgical solutions that can lead to sustained symptom resolution. Leveraging computational and imaging advances will be necessary as we seek to provide comprehensive treatment plans for patients.

Double outlet left atrium: successful management of a rare entity.

Double-outlet left atrium is an extremely rare congenital ventriculo-atrial mal-alignment anomaly, wherein, the left atrium drains into both ventricles, through either a common atrioventricular valve or two separate atrioventricular valves. The only egress from the right atrium is through an inter-atrial communication. We present a 16-month-old male, diagnosed to have double outlet left atrium and describe its surgical management.

Dendrimer nanotherapy targeting of glial dysfunction improves inflammation and neurobehavioral phenotype in adult female Mecp2-heterozygous mouse model of Rett syndrome.

Rett syndrome is an X-linked neurodevelopmental disorder caused by mutation of Mecp2 gene and primarily affects females. Glial cell dysfunction has been implicated in in Rett syndrome (RTT) both in patients and in mouse models of this disorder and can affect synaptogenesis, glial metabolism and inflammation. Here we assessed whether treatment of adult (5-6 months old) symptomatic Mecp2-heterozygous female mice with N-acetyl cysteine conjugated to dendrimer (D-NAC), which is known to target glia and modulate inflammation and oxidative injury, results in improved behavioral phenotype, sleep and glial inflammatory profile. We show that unbiased global metabolomic analysis of the hippocampus and striatum in adult Mecp2-heterozygous mice demonstrates significant differences in lipid metabolism associated with neuroinflammation, providing the rationale for targeting glial inflammation in this model. Our results demonstrate that treatment with D-NAC (10 mg/kg NAC) once weekly is more efficacious than equivalently dosed free NAC in improving the gross neurobehavioral phenotype in symptomatic Mecp2-heterozygous female mice. We also show that D-NAC therapy is significantly better than saline in ameliorating several aspects of the abnormal phenotype including paw clench, mobility, fear memory, REM sleep and epileptiform activity burden. Systemic D-NAC significantly improves microglial proinflammatory cytokine production and is associated with improvements in several aspects of the phenotype including paw clench, mobility, fear memory, and REM sleep, and epileptiform activity burden in comparison to saline-treated Mecp2-hetereozygous mice. Systemic glial-targeted delivery of D-NAC after symptom onset in an older clinically relevant Rett syndrome model shows promise in improving neurobehavioral impairments along with sleep pattern and epileptiform activity burden. These findings argue for the translational value of this approach for treatment of patients with Rett Syndrome.

Experience with surgical correction of double outlet both ventricles.

Double outlet both ventricles is a rare abnormal ventriculo-arterial malformation in which both great arterial trunks are committed to both the ventricles, albeit now being recognized with increasing frequency. Patients with the lesion present with a spectrum of clinical manifestations. The size and location of the interventricular communication dictate the feasibility of biventricular repair. Literature on the malformation, however, is sparse. We report our experience with five patients, all of whom underwent successful surgical biventricular repair.

Impact of H3K27 trimethylation loss in meningiomas: a meta-analysis.

Trimethylation of lysine 27 on histone 3 (H3K27me3) loss has been implicated in worse prognoses for patients with meningiomas. However, there have been challenges in measuring H3K27me3 loss, quantifying its impact, and interpreting its clinical utility. We conducted a systematic review across Pubmed, Embase, and Web of Science to identify studies examining H3K27me3 loss in meningioma. Clinical, histopathological, and immunohistochemistry (IHC) characteristics were aggregated. A meta-analysis was performed using a random-effects model to assess prevalence of H3K27me3 loss and meningioma recurrence risk. Study bias was characterized using the NIH Quality Assessment Tool and funnel plots. Nine publications met inclusion criteria with a total of 2376 meningioma cases. The prevalence of H3K27me3 loss was 16% (95% CI 0.09-0.27), with higher grade tumors associated with a significantly greater proportion of loss. H3K27me3 loss was more common in patients who were male, had recurrent meningiomas, or required adjuvant radiation therapy. Patients were 1.70 times more likely to have tumor recurrence with H3K27me3 loss (95% CI 1.35-2.15). The prevalence of H3K27me3 loss in WHO grade 2 and 3 meningiomas was found to be significantly greater in tissue samples less than five years old versus tissue of all ages and when a broader definition of IHC staining loss was applied. This analysis demonstrates that H3K27me3 loss significantly associates with more aggressive meningiomas. While differences in IHC and tumor tissue age have led to heterogeneity in studying H3K27me3 loss, a robust prognostic signal is present. Our findings suggest an opportunity to improve study design and standardize tissue processing to optimize clinical viability of this epigenetic marker.

A Scoping Review of the Application of BREAST-Q in Surgical Research.

Background: Collection of patient-reported outcome (PRO) data can facilitate cost-effective, evidence-based, and patient-centered care. The BREAST-Q has become the gold standard tool to measure PRO data in breast surgery. The last review of its application indicated that it was underutilized. Considering the evolution in breast surgery, the purpose of this study was to perform a scoping review of BREAST-Q application since 2015 and identify emerging trends and potential persistent gaps to guide patient-centered practice and future research in breast surgery. Methods: We performed an electronic literature review to identify publications published in English that used the BREAST-Q to assess patient outcomes. We excluded validation studies, review papers, conference abstracts, discussions, comments, and/or responses to previously published papers. Results: We identified 270 studies that met our inclusion criteria. Specific data was extracted to examine the evolution of the BREAST-Q application and examine clinical trends and research gaps. Discussion: Despite a significant increase in BREAST-Q studies, gaps in the understanding of the patient experience remain. The BREAST-Q is uniquely designed to measure quality of life and satisfaction with outcome and care. The prospective collection of center-specific data for every type of breast surgery will generate important information for the provision of patient-centered and evidence-based care.

Integration of Veterans Affairs Medical Centers Into Neurosurgical Residency Programs.

Veterans Affairs (VA) medical centers serve as a unique training environment for US residency programs. In this study, we aim to explore the scope and details of VA integration into neurosurgery resident training. We used data from the Accreditation Council for Graduate Medical Education database to provide an overview of neurosurgery training programs with an active VA affiliation and developed a multi-institutional survey to gather information related to rotation design, operative volume, expectations, and core training values. Of the 116 neurosurgery residency programs, 40 have an active affiliation with a VA medical center (34%). Residents most frequently rotated at the VA during their third postgraduate year, with an average rotation length of 7.5 months (range 2-21). Nearly all programs reported a weekly mix of clinic and operative days (96%), with residents longitudinally following patients throughout their rotations. Attending neurosurgeons from VA-affiliated programs reported operative experience (100%), independent decision-making (89%), and continuity of care (81%) as core values of VA neurosurgery rotations. Surgical volume varied between programs with an average of 13.4 ± 6.4 (SD) cases per month per rotating resident. A significant portion of neurosurgery residency programs in the United States incorporate VA rotations into resident training. Although rotation details vary from program-to-program, shared values include a strong operative experience, independent decision-making, and continuity of care. This analysis provides a comprehensive assessment of VA rotation structure across the country, which is valuable for programs considering implementing a VA rotation into their training program or modifying an existing rotation.

Application of radiomics to meningiomas: A systematic review.

BACKGROUND: Quantitative imaging analysis through radiomics is a powerful technology to non-invasively assess molecular correlates and guide clinical decision-making. There has been growing interest in image-based phenotyping for meningiomas given the complexities in management. METHODS: We systematically reviewed meningioma radiomics analyses published in PubMed, Embase, and Web of Science until December 20, 2021. We compiled performance data and assessed publication quality using the radiomics quality score (RQS). RESULTS: A total of 170 publications were grouped into 5 categories of radiomics applications to meningiomas: Tumor detection and segmentation (21%), classification across neurologic diseases (54%), grading (14%), feature correlation (3%), and prognostication (8%). A majority focused on technical model development (73%) versus clinical applications (27%), with increasing adoption of deep learning. Studies utilized either private institutional (50%) or public (49%) datasets, with only 68% using a validation dataset. For detection and segmentation, radiomic models had a mean accuracy of 93.1 ± 8.1% and a dice coefficient of 88.8 ± 7.9%. Meningioma classification had a mean accuracy of 95.2 ± 4.0%. Tumor grading had a mean area-under-the-curve (AUC) of 0.85 ± 0.08. Correlation with meningioma biological features had a mean AUC of 0.89 ± 0.07. Prognostication of the clinical course had a mean AUC of 0.83 ± 0.08. While clinical studies had a higher mean RQS compared to technical studies, quality was low overall with a mean RQS of 6.7 ± 5.9 (possible range -8 to 36). CONCLUSIONS: There has been global growth in meningioma radiomics, driven by data accessibility and novel computational methodology. Translatability toward complex tasks such as prognostication requires studies that improve quality, develop comprehensive patient datasets, and engage in prospective trials.

Automated detection of schizophrenia using deep learning: a review for the last decade.

Schizophrenia (SZ) is a devastating mental disorder that disrupts higher brain functions like thought, perception, etc., with a profound impact on the individual's life. Deep learning (DL) can detect SZ automatically by learning signal data characteristics hierarchically without the need for feature engineering associated with traditional machine learning. We performed a systematic review of DL models for SZ detection. Various deep models like long short-term memory, convolution neural networks, AlexNet, etc., and composite methods have been published based on electroencephalographic signals, and structural and/or functional magnetic resonance imaging acquired from SZ patients and healthy patients control subjects in diverse public and private datasets. The studies, the study datasets, and model methodologies are reported in detail. In addition, the challenges of DL models for SZ diagnosis and future works are discussed.

Machine Learning in the Classification of Pediatric Posterior Fossa Tumors: A Systematic Review.

Background: Posterior fossa tumors (PFTs) are a morbid group of central nervous system tumors that most often present in childhood. While early diagnosis is critical to drive appropriate treatment, definitive diagnosis is currently only achievable through invasive tissue collection and histopathological analyses. Machine learning has been investigated as an alternative means of diagnosis. In this systematic review and meta-analysis, we evaluated the primary literature to identify all machine learning algorithms developed to classify and diagnose pediatric PFTs using imaging or molecular data. Methods: Of the 433 primary papers identified in PubMed, EMBASE, and Web of Science, 25 ultimately met the inclusion criteria. The included papers were extracted for algorithm architecture, study parameters, performance, strengths, and limitations. Results: The algorithms exhibited variable performance based on sample size, classifier(s) used, and individual tumor types being investigated. Ependymoma, medulloblastoma, and pilocytic astrocytoma were the most studied tumors with algorithm accuracies ranging from 37.5% to 94.5%. A minority of studies compared the developed algorithm to a trained neuroradiologist, with three imaging-based algorithms yielding superior performance. Common algorithm and study limitations included small sample sizes, uneven representation of individual tumor types, inconsistent performance reporting, and a lack of application in the clinical environment. Conclusions: Artificial intelligence has the potential to improve the speed and accuracy of diagnosis in this field if the right algorithm is applied to the right scenario. Work is needed to standardize outcome reporting and facilitate additional trials to allow for clinical uptake.

Non-pharmacological interventions for sleep promotion in hospitalized children.

BACKGROUND: Healthy sleep is an important component of childhood development. Changes in sleep architecture, including sleep stage composition, quantity, and quality from infancy to adolescence are a reflection of neurologic maturation. Hospital admission for acute illness introduces modifiable risk factors for sleep disruption that may negatively affect active brain development during a period of illness and recovery. Thus, it is important to examine non-pharmacologic interventions for sleep promotion in the pediatric inpatient setting. OBJECTIVES: To evaluate the effect of non-pharmacological sleep promotion interventions in hospitalized children and adolescents on sleep quality and sleep duration, child or parent satisfaction, cost-effectiveness, delirium incidence, length of mechanical ventilation, length of stay, and mortality. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, three other databases, and three trials registers to December 2021. We searched Google Scholar, and two websites, handsearched conference abstracts, and checked reference lists of included studies. SELECTION CRITERIA: Randomized controlled trials (RCTs) or quasi-RCTs, including cross-over trials, investigating the effects of any non-pharmacological sleep promotion intervention on the sleep quality or sleep duration (or both) of children aged 1 month to 18 years in the pediatric inpatient setting (intensive care unit [ICU] or general ward setting). DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial eligibility, evaluated risk of bias, extracted and synthesized data, and used the GRADE approach to assess certainty of evidence. The primary outcomes were changes in both objective and subjective validated measures of sleep in children; secondary outcomes were child and parent satisfaction, cost-effectiveness ratios, delirium incidence or delirium-free days at time of hospital discharge, duration of mechanical ventilation, length of hospital stay, and mortality. MAIN RESULTS: We included 10 trials (528 participants; aged 3 to 22 years) in inpatient pediatric settings. Seven studies were conducted in the USA, two in Canada, and one in Brazil. Eight studies were funded by government, charity, or foundation grants. Two provided no information on funding. Eight studies investigated behavioral interventions (massage, touch therapy, and bedtime stories); two investigated physical activity interventions. Duration and timing of interventions varied widely. All studies were at high risk of performance bias due to the nature of the intervention, as participants, parents, and staff could not be masked to group assignment. We were unable to perform a quantitative synthesis due to substantial clinical heterogeneity. Behavioral interventions versus usual care Five studies (145 participants) provided low-certainty evidence of no clear difference between multicomponent relaxation interventions and usual care on objective sleep measures. Overall, evidence from single studies found no clear differences in daytime or nighttime sleep measures (33 participants); any sleep parameter (48 participants); or daytime or nighttime sleep or nighttime arousals (20 participants). One study (34 participants) reported no effect of massage on nighttime sleep, sleep efficiency (SE), wake after sleep onset (WASO), or total sleep time (TST) in adolescents with cancer. Evidence from a cross-over study in 10 children with burns suggested touch therapy may increase TST (391 minutes, interquartile range [IQR] 251 to 467 versus 331 minutes, IQR 268 to 373; P = 0.02); SE (76, IQR 53 to 90 versus 66, IQR 55 to 78; P = 0.04); and the number of rapid eye movement (REM) periods (4.5, IQR 2 to 5 versus 3.5, IQR 2 to 4; P = 0.03); but not WASO, sleep latency (SL), total duration of REM, or per cent of slow wave sleep. Four studies (232 participants) provided very low-certainty evidence on subjective measures of sleep. Evidence from single studies found that sleep efficiency may increase, and the percentage of nighttime wakefulness may decrease more over a five-day period following a massage than usual care (72 participants). One study (48 participants) reported an improvement in Children's Sleep Habits Questionnaire scores after discharge in children who received a multicomponent relaxation intervention compared to usual care. In another study, mean sleep duration per sleep episode was longer (23 minutes versus 15 minutes), and time to fall asleep was shorter (22 minutes versus 27 minutes) following a bedtime story versus no story (18 participants); and children listening to a parent-recorded story had longer SL than when a parent was present (mean 57.5 versus 43.5 minutes); both groups reported longer SL than groups who had a stranger-recorded story, and those who had no story and absent parents (94 participants; P < 0.001). In one study (34 participants), 87% (13/15) of participants felt they slept better following massage, with most parents (92%; 11/12) reporting they wanted their child to receive a massage again. Another study (20 participants) reported that parents thought the music, touch, and reading components of the intervention were acceptable, feasible, and had positive effects on their children (very low-certainty evidence). Physical activity interventions versus usual care One study (29 participants) found that an enhanced physical activity intervention may result in little or no improvement in TST or SE compared to usual care (low-certainty evidence). Another study (139 participants), comparing play versus no play found inconsistent results on subjective measures of sleep across different ages (TST was 49% higher for the no play groups in 4- to 7-year olds, 10% higher in 7- to 11-year olds, and 22% higher in 11- to 14-year olds). This study also found inconsistent results between boys and girls (girls in the first two age groups in the play group slept more than the no play group). No study evaluated child or parent satisfaction for behavioral interventions, or cost-effectiveness, delirium incidence or delirium-free days at hospital discharge, length of mechanical ventilation, length of hospital stay, or mortality for either behavioral or physical activity intervention. AUTHORS' CONCLUSIONS: The included studies were heterogeneous, so we could not quantitatively synthesize the results. Our narrative summary found inconsistent, low to very low-certainty evidence. Therefore, we are unable to determine how non-pharmacologic sleep promotion interventions affect sleep quality or sleep duration compared with usual care or other interventions. The evidence base should be strengthened through design and conduct of randomized trials, which use validated and highly reliable sleep assessment tools, including objective measures, such as polysomnography and actigraphy.

The cognitive-phenomenological assessment of delusions and hallucinations at the early intervention in psychosis service stage: The results of a quality improvement project.

AIM: Clinical assessments are vital for gaining an understanding of a patients' presenting problem. A priority for Early Intervention in Psychosis Service staff is understanding and supporting their patients' experiences of hallucinations and/or delusions. We aimed to identify what cognitive-phenomenology dimensions of hallucinations and delusions EIPS staff were assessing with their patients. METHODS: We developed a brief checklist of cognitive-phenomenological dimensions of hallucinations and delusions called the Lived Experience Symptom Survey (LESS) based on relevant literature. As part of a Quality Improvement Project, we reviewed the health records of a sub-sample of EIPS patients using the LESS identifying whether each dimension was present or absent. RESULTS: We found that all patients had been asked about the content of their hallucinations and/or delusions, and the majority had been asked about the valence of this content. Despite patients having experienced psychosis for almost 2 years on average, less than half of patients were asked about the potential or actual harm associated with these symptoms. All other cognitive-phenomenological dimensions were assessed inconsistently. CONCLUSIONS: The assessment of hallucination and delusions in our EIPS was inconsistent and incomprehensive. These findings require replication in other EIPS' but may point to a need for guidelines and training around how to conduct a thorough assessment of hallucinations and delusions for current and future EIPS staff. Improved assessment of these symptoms will aid the development of risk assessments and treatment plans.

Large collateral from the right coronary artery in a case of coarctation of the aorta with bilateral subclavian artery aneurysms in an adult.

Here, we present a case of a 26-year-old gentleman who presented with a rare combination of bilateral huge subclavian artery aneurysms, coarctation of the aorta with a large coronary artery collateral and a bovine aortic arch. Various mediastinal collaterals have been described in previous cases of coarctation of the aorta, but the association of coronary collaterals is a rare occurrence. To the best of our knowledge, this case has not been reported in literature yet.

Isolated ventricular inversion with hypoplastic right ventricle and pulmonary stenosis in an adolescent with situs solitus: a rare combination.

Isolated ventricular inversion with situs solitus is a severe and rare congenital cardiac malformation characterised by an atrioventricular discordance but with ventriculo-arterial concordance. Here, we present the rare case of an adolescent with isolated ventricular inversion and hypoplasia of the left-sided morphological right ventricle and pulmonary stenosis, a first of its kind to be reported in the literature.

Chemogenetics as a neuromodulatory approach to treating neuropsychiatric diseases and disorders.

Chemogenetics enables precise, non-invasive, and reversible modulation of neural activity via the activation of engineered receptors that are pharmacologically selective to endogenous or exogenous ligands. With recent advances in therapeutic gene delivery, chemogenetics is poised to support novel interventions against neuropsychiatric diseases and disorders. To evaluate its translational potential, we performed a scoping review of applications of chemogenetics that led to the reversal of molecular and behavioral deficits in studies relevant to neuropsychiatric diseases and disorders. In this review, we present these findings and discuss the potential and challenges for using chemogenetics as a precision medicine-based neuromodulation strategy.