Karawun: a software package for assisting evaluation of advances in multimodal imaging for neurosurgical planning and intraoperative neuronavigation.

PURPOSE: The neuroimaging research community-which includes a broad range of scientific, medical, statistical, and engineering disciplines-has developed many tools to advance our knowledge of brain structure, function, development, aging, and disease. Past research efforts have clearly shaped clinical practice. However, translation of new methodologies into clinical practice is challenging. Anything that can reduce these barriers has the potential to improve the rate at which research outcomes can contribute to clinical practice. In this article, we introduce Karawun, a file format conversion tool, that has become a key part of our work in translating advances in diffusion imaging acquisition and analysis into neurosurgical practice at our institution. METHODS: Karawun links analysis workflows created using open-source neuroimaging software, to Brainlab (Brainlab AG, Munich, Germany), a commercially available surgical planning and navigation suite. Karawun achieves this using DICOM standards supporting representation of 3D structures, including tractography streamlines, and thus offers far more than traditional screenshot or color overlay approaches. RESULTS: We show that neurosurgical planning data, created from multimodal imaging data using analysis methods implemented in open-source research software, can be imported into Brainlab. The datasets can be manipulated as if they were created by Brainlab, including 3D visualizations of white matter tracts and other objects. CONCLUSION: Clinicians can explore and interact with the results of research neuroimaging pipelines using familiar tools within their standard clinical workflow, understand the impact of the new methods on their practice and provide feedback to methods developers. This capability has been important to the translation of advanced analysis techniques into practice at our institution.

Pediatric pineoblastoma: A pooled outcome study of North American and Australian therapeutic data.

Background: Pineoblastoma is a rare brain tumor usually diagnosed in children. Given its rarity, no pineoblastoma-specific trials have been conducted. Studies have included pineoblastoma accruing for other embryonal tumors over the past 30 years. These included only occasional children with pineoblastoma, making clinical features difficult to interpret and determinants of outcome difficult to ascertain. Patients and Methods: Centrally or independently reviewed series with treatment and survival data from North American and Australian cases were pooled. To investigate associations between variables, Fisher's exact tests, Wilcoxon-Mann-Whitney tests, and Spearman correlations were used. Kaplan-Meier plots, log-rank tests, and Cox proportional hazards models were used in survival analyses. Results: We describe a pooled cohort of 178 pineoblastoma cases from Children's Oncology Group (n = 82) and institutional series (n = 96) over 30 years. Children <3 years of age have significantly worse survival compared to older children, with 5-year progression-free survival (PFS) and overall survival (OS) estimates of 13.5 ± 5.1% and 16.2 ± 5.3%, respectively, compared with 60.8 ± 5.6% and 67.3 ± 5.0% for ≥3 years old (both P < .0001). Multivariable analysis showed male sex was associated with worse PFS in children <3 years of age (hazard ratio [HR] 3.93, 95% CI 1.80-8.55; P = .0006), suggestive of sex-specific risks needing future validation. For children ≥3 years of age, disseminated disease at diagnosis was significantly associated with an inferior 5-year PFS of 39.2 ± 9.7% (HR 2.88, 95% CI 1.52-5.45; P = .0012) and 5-year OS of 49.8 ± 9.1% (HR 2.87, 95% CI 1.49-5.53; P = .0016). Conclusion: Given the rarity of this tumor, prospective, collaborative international studies will be vital to improving the long-term survival of these patients.

Assessment of intraoperative diffusion EPI distortion and its impact on estimation of supratentorial white matter tract positions in pediatric epilepsy surgery.

The effectiveness of correcting diffusion Echo Planar Imaging (EPI) distortion and its impact on tractography reconstruction have not been adequately investigated in the intraoperative MRI setting, particularly for High Angular Resolution Diffusion Imaging (HARDI) acquisition. In this study, we evaluated the effectiveness of EPI distortion correction using 27 legacy intraoperative HARDI datasets over two consecutive surgical time points, acquired without reverse phase-encoded data, from 17 children who underwent epilepsy surgery at our institution. The data was processed with EPI distortion correction using the Synb0-Disco technique (Schilling et al., 2019) and without distortion correction. The corrected and uncorrected b0 diffusion-weighted images (DWI) were first compared visually. The mutual information indices between the original T1-weighted images and the fractional anisotropy images derived from corrected and uncorrected DWI were used to quantify the effect of distortion correction. Sixty-four white matter tracts were segmented from each dataset, using a deep-learning based automated tractography algorithm for the purpose of a standardized and unbiased evaluation. Displacement was calculated between tracts generated before and after distortion correction. The tracts were grouped based on their principal morphological orientations to investigate whether the effects of EPI distortion vary with tract orientation. Group differences in tract distortion were investigated both globally, and regionally with respect to proximity to the resecting lesion in the operative hemisphere. Qualitatively, we observed notable improvement in the corrected diffusion images, over the typically affected brain regions near skull-base air sinuses, and correction of additional distortion unique to intraoperative open cranium images, particularly over the resection site. This improvement was supported quantitatively, as mutual information indices between the FA and T1-weighted images were significantly greater after the correction, compared to before the correction. Maximum tract displacement between the corrected and uncorrected data, was in the range of 7.5 to 10.0 mm, a magnitude that would challenge the safety resection margin typically tolerated for tractography-informed surgical guidance. This was particularly relevant for tracts oriented partially or fully in-line with the acquired diffusion phase-encoded direction. Portions of these tracts passing close to the resection site demonstrated significantly greater magnitude of displacement, compared to portions of tracts remote from the resection site in the operative hemisphere. Our findings have direct clinical implication on the accuracy of intraoperative tractography-informed image guidance and emphasize the need to develop a distortion correction technique with feasible intraoperative processing time.

Global Epidemiology of Craniosynostosis: A Systematic Review and Meta-Analysis.

OBJECTIVE: Craniosynostosis leads to craniofacial deformity and may result in raised intracranial pressure, neurocognitive deficits, and psychosocial issues if left untreated. The global epidemiology of craniosynostosis is unknown. We conducted a meta-analysis to estimate global birth prevalence. METHODS: PubMed, Embase, and Scopus were searched. Articles were screened by title and abstract and then full text. Meta-analysis of birth prevalence was conducted. Birth prevalence figures were combined with metrics detailing the number of births in 2019 to estimate the number of children worldwide born with craniosynostosis annually. RESULTS: Of 1378 resultant articles, 24 studies were included, including 20 providing data for craniosynostosis overall and 9 for nonsyndromic craniosynostosis. World Health Organization regions of included studies were 9 (37.5%) European Region, 8 (33.3%) Region of the Americas, 4 (16.7%) Western Pacific region, 2 (8.3%) African Region, and 1 (4.2%) Eastern Mediterranean Region. Lower middle-income countries represented only 4% of study manuscripts. The overall birth prevalence of craniosynostosis was 5.9 per 10,000 live births (20 studies; 95% confidence interval [CI]: 3.9, 8.4; I2 = 100%). The birth prevalence of nonsyndromic craniosynostosis was 5.2 per 10,000 live births (9 studies; 95% CI: 3.4, 7.3; I2 = 98%). The number of children born globally with craniosynostosis in 2019 was estimated to be 84,665 (95% CI: 55,965, 120,540), including 72,857 (95% CI: 47,637, 120,280) with nonsyndromic craniosynostosis. CONCLUSIONS: Craniosynostosis is a common condition that affects the neurocognitive and craniofacial skeletal development of children worldwide. Initiatives to scale up capacity for craniosynostosis epidemiologic research and clinical care are warranted, particularly in low- and middle-income countries.

One-Stage, Limited-Resection Epilepsy Surgery for Bottom-of-Sulcus Dysplasia.

OBJECTIVE: To determine whether 1-stage, limited corticectomy controls seizures in patients with MRI-positive, bottom-of-sulcus dysplasia (BOSD). METHODS: We reviewed clinical, neuroimaging, electrocorticography (ECoG), operative, and histopathology findings in consecutively operated patients with drug-resistant focal epilepsy and MRI-positive BOSD, all of whom underwent corticectomy guided by MRI and ECoG. RESULTS: Thirty-eight patients with a median age at surgery of 10.2 (interquartile range [IQR] 6.0-14.1) years were included. BOSDs involved eloquent cortex in 15 patients. Eighty-seven percent of patients had rhythmic spiking on preresection ECoG. Rhythmic spiking was present in 22 of 24 patients studied with combined depth and surface electrodes, being limited to the dysplastic sulcus in 7 and involving the dysplastic sulcus and gyral crown in 15. Sixty-eight percent of resections were limited to the dysplastic sulcus, leaving the gyral crown. Histopathology was focal cortical dysplasia (FCD) type IIb in 29 patients and FCDIIa in 9. Dysmorphic neurons were present in the bottom of the sulcus but not the top or the gyral crown in 17 of 22 patients. Six (16%) patients required reoperation for postoperative seizures and residual dysplasia; reoperation was not correlated with ECoG, neuroimaging, or histologic abnormalities in the gyral crown. At a median 6.3 (IQR 4.8-9.9) years of follow-up, 33 (87%) patients are seizure-free, 31 off antiseizure medication. CONCLUSION: BOSD can be safely and effectively resected with MRI and ECoG guidance, corticectomy potentially being limited to the dysplastic sulcus, without need for intracranial EEG monitoring and functional mapping. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that 1-stage, limited corticectomy for BOSD is safe and effective for control of seizures.

Communication Empowerment Framework: An integrative framework to support effective communication and interaction between carers and people living with dementia.

OBJECTIVES: To demonstrate the power of integrating three theoretical perspectives (Mentalization Theory, Perceptual Control Theory and the Communicative Impact model), which jointly illuminate the communication challenges and opportunities faced by family carers of people with dementia. To point the way to how this framework informs the design and delivery of carer communication and interaction training. METHOD: Conceptual synthesis based on a narrative review of relevant literature, supported by examples of family carers. RESULTS: We use the conceptual models to show how the capacity to mentalize ("holding mind in mind") offers a greater sense of control over internal and external conflicts, with the result that they can be deescalated in pursuit of mutual goals. CONCLUSIONS: The integrative conceptual framework presented here highlights specific psychological and relational mechanisms that can be targeted through carer training to enhance communication with a person living with dementia.

Second-hit DEPDC5 mutation is limited to dysmorphic neurons in cortical dysplasia type IIA.

Focal cortical dysplasia (FCD) causes drug-resistant epilepsy and is associated with pathogenic variants in mTOR pathway genes. How germline variants cause these focal lesions is unclear, however a germline + somatic "2-hit" model is hypothesized. In a boy with drug-resistant epilepsy, FCD, and a germline DEPDC5 pathogenic variant, we show that a second-hit DEPDC5 variant is limited to dysmorphic neurons, and the somatic mutation load correlates with both dysmorphic neuron density and the epileptogenic zone. These findings provide new insights into the molecular and cellular correlates of FCD determining drug-resistant epilepsy and refine conceptualization of the epileptogenic zone.

Outcome of vein of Galen malformation presenting in the neonatal period.

OBJECTIVE: Vein of Galenaneurysmal malformation (VGAM) is a rare but important congenital malformation presenting to neonatal intensive care units (NICUs), and with a change from surgical to endovascular management, survival for this condition has improved. However, there is little reported about the medical management decisions of infants with this condition and the associated long-term neurodevelopmental outcomes. We aim to report a single centre experience of both acute treatment and long-term outcomes of VGAM for those infants admitted to our NICU soon after birth. DESIGN: Retrospective cohort study over a 15-year period from 2001 to 2015 inclusive. SETTING: A quaternary NICU at The Royal Children's Hospital, Melbourne, Australia. PARTICIPANTS: 24 newborn infants referred for management of VGAM. There were no eligibility criteria set for this study; all presenting infants were included. INTERVENTIONS: None. MAIN OUTCOMES MEASURES: Clinical neuroimaging data were gathered. Surviving children were formally assessed with a battery of tests administered by a neuropsychologist and occupational therapist/physiotherapist at various ages across early to middle childhood. RESULTS: Fifteen neonates with VGAM did not survive beyond their NICU admission. 10 of these were not offered endovascular intervention. Of the nine surviving infants, only one had a normal neurodevelopmental outcome. CONCLUSIONS: The mortality of VGAM presenting in the neonatal period was high, and rates of normal neurodevelopmental outcome for survivors were low. These findings contribute to our understanding of which neonates should be treated and highlights the importance of providing clinical neurodevelopmental follow-up to survivors beyond their infant years.

Pediatric Neuroschistosomiasis: A Case Report and Review of the Literature.

Neuroschistosomiasis is a rare but severe manifestation of Schistosoma infection. Diagnosis is challenging and surgical biopsy is often required to confirm diagnosis and exclude malignancy. We present a pediatric case of presumed pseudotumoral cerebral schistosomiasis secondary to Schistosoma mansoni with an excellent therapeutic response to empirical praziquantel and corticosteroid treatment.

Australian Clinical Consensus Guideline: The diagnosis and acute management of childhood stroke.

Stroke is among the top 10 causes of death in children and survivors carry resulting disabilities for decades, at substantial cost to themselves and their families. Children are not currently able to access reperfusion therapies, due to limited evidence supporting safety and efficacy and long diagnostic delays. The Australian Clinical Consensus Guideline for the Diagnosis and Acute Management of Childhood Stroke was developed to minimize unwarranted variations in care and document best evidence on the risk factors, etiologies, and conditions mimicking stroke that differ from adults. Clinical questions were formulated to inform systematic database searches from 2007 to 2017, limited to English and pediatric studies. SIGN methodology and the National Health and Medical Research Council system were used to screen and classify the evidence. The Grades of Recommendation, Assessment, Development, and Evaluation system (GRADE) was used to grade evidence as strong or weak. The Guideline provides more than 60 evidence-based recommendations to assist prehospital and acute care clinicians in the rapid identification of childhood stroke, choice of initial investigation, to confirm diagnosis, determine etiology, selection of the most appropriate interventions to salvage brain at risk, and prevent recurrence. Recommendations include advice regarding the management of intracranial pressure and congenital heart disease. Implementation of the Guideline will require reorganization of prehospital and emergency care systems, including the development of regional stroke networks, pediatric Code Stroke, rapid magnetic resonance imaging and accreditation of primary pediatric stroke centers with the capacity to offer reperfusion therapies. The Guideline will allow auditing to benchmark timelines of care, access to acute interventions, and outcomes. It will also facilitate the development of an Australian childhood stroke registry, with data linkage to international registries, to allow for accurate data collection on stroke incidence, treatment, and outcomes.

Formulaic Sequences as a Regulatory Mechanism for Cognitive Perturbations During the Achievement of Social Goals.

This paper explores two questions central to understanding the nature of formulaic sequences: (1) What are they for? and (2) What determines how many there are? The "Communicative Impact" model draws into a single account how language is shaped by cognitive processing on the one hand and socio-interactional function on the other: Formulaic sequences play a range of coordinated roles in neutralizing unanticipated perturbations in the cognitive management of language, so the speaker's socio-interactional goals can still be achieved. One role involves compensatory actions to sustain fluency. However, these actions are themselves context-sensitive, so the balance of types of formulaic sequence will vary according to situation. The model applies equally to temporary cognitive pressure and chronic problems such as dementia and limited linguistic competency in a foreign language.

Three patterns of fronto-orbital remodeling for metopic synostosis: comparison of cranial growth outcomes.

BACKGROUND: The authors compared cranial growth across three patterns of fronto-orbital remodeling for metopic synostosis. METHODS: The authors reviewed all patients who underwent fronto-orbital remodeling for isolated metopic synostosis between 2006 and 2009. Inclusion criteria consisted of patients with preoperative, short-term postoperative (4 to 12 months), and long-term postoperative (>36 months) three-dimensional photographs. Patients were categorized by fronto-orbital remodeling pattern: group 1, retrocoronal; group 2, partial coronal; and group 3, precoronal. Head circumference, minimum frontal breadth (ft-ft), and maximum cranial length were measured by three-dimensional photographs, converted to standard Z scores, and compared. RESULTS: Thirty-one patients met inclusion criteria (group 1, n=12; group 2, n=10; and group 3, n=9). Group 1 presented with the greatest phenotypic severity. From preoperative to short-term postoperative assessment, head circumference Z scores rose for group 1 but dropped for groups 2 and 3, and the three groups demonstrated equivalent increases in minimum frontal breadth Z scores. From short-term to long-term postoperatively, the three groups demonstrated similar stability in head circumference Z scores but decreased minimum frontal breadth Z scores. From preoperatively to long-term postoperatively, head circumference Z scores rose for group 1 but fell for groups 2 and 3 (change in Z score, 0.5, -0.5, and -0.7, respectively; p=0.06) and the three groups demonstrated equivalent drops in minimum frontal breadth Z scores. Across preoperative to short-term postoperative and preoperative to long-term postoperative assessment, group 1 displayed the least drop in maximum cranial length Z scores. CONCLUSIONS: Retrocoronal patterns of fronto-orbital remodeling provide long-term gains in head circumference percentile and the least growth impairment in cranial length. Irrespective of osteotomy design, expansion in frontal breadth relapses significantly over time. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Pediatric dural arteriovenous malformations.

Pediatric dural arteriovenous malformations (dAVMs) are rare lesions that have a high mortality rate and require complex management. The authors report 3 cases of pediatric dAVMs that presented with macrocrania and extracranial venous distension. Dural sinus thrombosis developed in 2 of the cases prior to any intervention, which is an unusual occurrence for this particular disease. All 3 cases were treated using staged endovascular embolization with a favorable outcome in 1 case and a poor outcome in the other 2 cases. Complications developed in all cases and included dural sinus thrombosis, parenchymal hemorrhage, intracranial venous hypertension, and seizures. The strategies and challenges used in managing these patients will be presented and discussed, along with a review of the literature. While outcomes remain poor, the authors conclude that prompt treatment with endovascular embolization provides the best results for children with these lesions. A well-established venous collateral circulation draining directly to the internal jugular veins may further improve the rate of favorable outcome after embolization.

Total cranial vault remodeling for isolated sagittal synostosis: part I. Postoperative cranial suture patency.

BACKGROUND: Total vault reconstruction addresses all phenotypic aspects of scaphocephaly. The clinical implications of remodeling across open cranial sutures, however, remain unclear. The purpose of this study was to assess patency of unaffected sutures following total vault remodeling for isolated sagittal synostosis. METHODS: The authors reviewed routine postoperative computed tomographic scans of patients who underwent total vault remodeling for isolated sagittal synostosis between 2004 and 2008. Sutural patency was scored by a single reviewer as follows: 0 = closed, 1 = partial, and 2 = open. Individual suture scores were tallied for a total sutural patency score. Computed tomographic scans were stratified by postoperative time and craniofacial surgeon. RESULTS: Forty-two patients met the inclusion criteria. Individual sutural closure rates were 42.6, 38.3, 74.5, and 74.5 percent for right coronal, left coronal, right lambdoidal, and left lambdoidal sutures, respectively. Lambdoidal sutures had a significantly higher rate of closure than coronal sutures (OR(Closure), 4.3; 95 percent CI, 2.3 to 8.0; p < 0.001); lambdoidal patency significantly changed over time (χ2 = 9.9, p = 0.04). Across craniofacial surgeons, coronal and lambdoidal patency were equivalent. The total sutural patency score did not significantly correlate with postoperative time, surgical age, preoperative cephalic index, or craniofacial surgeon. CONCLUSIONS: Total vault remodeling for isolated sagittal synostosis results in a high degree of secondary craniosynostosis. Lambdoidal sutures are especially prone to closure, with their patency diminishing over time. At this time, radiographic fusion of adjacent sutures following surgery has not been related to any difference in head shape. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Longitudinal study of the neurodevelopmental characteristics of treated and untreated nonsyndromic craniosynostosis in infancy.

PURPOSE: Nonsyndromic craniosynostosis (NSC) are a group of congenital disorders sharing premature fusion of one or more of the cranial sutures that restricts and distorts growth of the skull and underlying brain. This study examined the neurodevelopmental sequelae of NSC both prior to and following reconstructive cranial surgery. METHODS: Sixty-four consecutive referrals with mixed forms of untreated NSC aged 4 to 16 months (M = 8.9, SD = 2.9) comprised the pre-operative cohort. Forty-four of these patients aged 6 to 32 months (M = 21.2, SD = 4.5) underwent post-operative developmental evaluation. Neurodevelopmental function was assessed with the mental (Mental Development Index) and motor (Psychomotor Development Index) scales of the Bayley Scales of Infant Development-2nd edition. RESULTS: Children with untreated NSC displayed significantly lower mental (M = 97.5) and motor (M = 87.7) scores than normative expectations, with the distribution of scores also differing significantly from the normative distribution. Post-operatively, children continued to display significantly lower mental (M = 89.5) and motor (M = 88.0) abilities, with mental abilities falling significantly lower than pre-operative levels. An increased prevalence of severe motor delay was found, and no child displayed accelerated development. Subgroup comparisons revealed no differences in mental or motor skills between the primary diagnostic subtypes (sagittal and metopic synostosis) both prior to and following corrective surgery. CONCLUSIONS: NSC is associated with an increased incidence of developmental delay in both treated and untreated conditions. Timing of surgery appears unrelated to developmental outcome.

Delayed sagittal sinus tear: a complication of spring cranioplasty for sagittal craniosynostosis.

Spring cranioplasty is now a well-established surgical technique in the treatment of sagittal craniosynostosis. It is widely regarded as a less invasive modality compared with operations such as cranial vault remodeling. Indeed, very few complications have been described in the literature in association with spring cranioplasty. We present a case of delayed sagittal sinus tear with hemorrhage following spring cranioplasty in a 4-month-old patient with sagittal craniosynostosis. Likely causes of the injury are discussed highlighting sagittal sinus injury as a potential risk of spring cranioplasty.

Analysis of morbidity and mortality in surgical management of craniosynostosis.

Multidisciplinary care involving plastic surgery and neurosurgery is generally accepted as optimal to manage craniosynostosis to avoid complications and to identify patients at risk. We conducted a retrospective 30-year review of craniosynostosis surgery at a single major craniofacial institute to establish the rate and predictors of complications. Medical records of 796 consecutive patients who underwent primary surgery for craniosynostosis from 1981 to 2010 at our institute were analyzed for complications. Complications were defined as intraoperative and postoperative adverse events requiring changed management. Reoperation was defined as a repeat transcranial procedure. Multivariate logistic regression was used to identify predictors for complications or revision. Across the years, the procedures evolved from technically simple to complex, which increased complications but better outcomes. Complications occurred in 111 patients (14%), and 33 (5.4%) needed major revision. Multivariate analysis identified multisuture and syndromic craniosynostosis, more recent surgeries, younger age (<9 months), spring-assisted cranioplasty, longer surgery, and greater transfusion as predictors of complications. Patients with syndromic and multisutural craniosynostosis and those operated on younger than 9 months had increased risk of major revision surgery for regression to phenotype. Our experience over 30 years indicates that pediatric transcranial craniosynostosis surgery can be safely carried out in our tertiary referral center. There were no deaths from primary surgery, and complication and reoperation rates mirror those of other published studies. Syndromic and complex craniosynostosis predicted both complications and need for major revision. Spring cranioplasty was associated with higher complications. Overall results support a recommended age for craniosynostosis surgery between 9 and 12 months.