The preoperative incidence of raised intracranial pressure in nonsyndromic sagittal craniosynostosis is underestimated in the literature

Intracranial Pressure Patterns in Children with Sagittal Craniosynostosis

BACKGROUND

Elevated intracranial pressure (ICP) in sagittal craniosynostosis has a wide spectrum of reported incidence, and patterns are not well understood across infancy and childhood. Characterizing the natural history of ICP in this population may clarify risks for neurocognitive delay and inform treatment decisions.

METHODS

Infants and children with sagittal craniosynostosis and unaffected control subjects were prospectively evaluated with spectral-domain optical coherence tomography from 2014 to 2021. Elevated ICP was determined based on previously validated algorithms using retinal optical coherence tomography parameters.

RESULTS

Seventy-two patients with isolated sagittal craniosynostosis and 25 control subjects were evaluated. Overall, 31.9% ( n = 23) of patients with sagittal craniosynostosis had evidence of ICP greater than or equal to 15 mmHg, and 27.8% ( n = 20) of patients had ICP greater than or equal to 20 mmHg. Children with sagittal craniosynostosis younger than 6 months were more likely to have normal ICP (88.6% <15 mmHg; 91.4% <20 mmHg) than those aged between 6 and 12 months (54.5%, P = 0.013; 54.5%, P = 0.005) than those older than 12 months (46.2%, P < 0.001; 53.8%, P = 0.001). ICP was directly correlated with severity of scaphocephaly ( P = 0.009). No unaffected control subjects at any age exhibited retinal thickening suggestive of elevated ICP.

CONCLUSION

Elevated ICP is rare in isolated sagittal craniosynostosis younger than 6 months, but it becomes significantly more common after 6 months of age, and may correlate with severity of scaphocephaly.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

The Craniofacial Collaboration UK: Developmental Outcomes in 7- and 10-Year-Old Children With Sagittal Synostosis

The Craniofacial Collaboration UK (CC-UK) protocol is a shared agreement across the 4 UK Highly Specialist Craniofacial Centres (HSCCs) to conduct robust neurodevelopmental and psychosocial clinical screening for children with craniosynostosis. This agreement allows for the analysis of outcomes of a homogenous sample of children with single suture craniosynostosis (SSC), a frequent limitation of the existing research. The current study is the latest analysis of CC-UK data on behavioral, cognitive, and psychosocial outcomes. The focus of this analysis is 7- and 10-year-olds with nonsyndromic sagittal synostosis (SS) who have undergone primary corrective surgery and completed routine clinical screening at 1 of the 4 HSCCs since the introduction of the CC-UK protocol. Due to changes in clinical pathways, only data from 3 HSCCs is included to preserve homogeneity. Results show that the majority of children with SS fall within the average range across behavioral and neurodevelopmental domains. A notable exception was a task involving perceptual reasoning and visuomotor skills (Block Design). Although this difference was small and the mean score remained within the average range, it suggests some increased risk of subtle difficulty with such skills for children with SS. Across other measures, there was no consistent evidence of any significantly increased risk of poorer outcomes, in line with findings of previous CC-UK papers. Understanding the psychological phenotype of SS is a key research priority for parents and clinicians, and the current study is another step toward achieving this goal.

Cranial bone thickness and density anomalies quantified from CT images can identify chronic increased intracranial pressure

PURPOSE

The diagnosis of chronic increased intracranial pressure (IIP)is often based on subjective evaluation or clinical metrics with low predictive value. We aimed to quantify cranial bone changes associated with pediatric IIP using CT images and to identify patients at risk.

METHODS

We retrospectively quantified local cranial bone thickness and mineral density from the CT images of children with chronic IIP and compared their statistical differences to normative children without IIP adjusting for age, sex and image resolution. Subsequently, we developed a classifier to identify IIP based on these measurements. Finally, we demonstrated our methods to explore signs of IIP in patients with non-syndromic sagittal craniosynostosis (NSSC).

RESULTS

We quantified a significant decrease of bone density in 48 patients with IIP compared to 1,018 normative subjects (P < .001), but no differences in bone thickness (P = .56 and P = .89 for age groups 0-2 and 2-10 years, respectively). Our classifier demonstrated 83.33% (95% CI: 69.24%, 92.03%) sensitivity and 87.13% (95% CI: 84.88%, 89.10%) specificity in identifying patients with IIP. Compared to normative subjects, 242 patients with NSSC presented significantly lower cranial bone density (P < .001), but no differences were found compared to patients with IIP (P = .57). Of patients with NSSC, 36.78% (95% CI: 30.76%, 43.22%) presented signs of IIP.

CONCLUSION

Cranial bone changes associated with pediatric IIP can be quantified from CT images to support earlier diagnoses of IIP, and to study the presence of IIP secondary to cranial pathology such as non-syndromic sagittal craniosynostosis.

Understanding the influence of surgical parameters on craniofacial surgery outcomes: a computational study

Sagittal craniosynostosis (SC) is a congenital condition whereby the newborn skull develops abnormally owing to the premature ossification of the sagittal suture. Spring-assisted cranioplasty (SAC) is a minimally invasive surgical technique to treat SC, where metallic distractors are used to reshape the newborn's head. Although safe and effective, SAC outcomes remain uncertain owing to the limited understanding of skull-distractor interaction and the limited information provided by the analysis of single surgical cases. In this work, an SC population-averaged skull model was created and used to simulate spring insertion by means of the finite-element analysis using a previously developed modelling framework. Surgical parameters were varied to assess the effect of osteotomy and spring positioning, as well as distractor combinations, on the final skull dimensions. Simulation trends were compared with retrospective measurements from clinical imaging (X-ray and three-dimensional photogrammetry scans). It was found that the on-table post-implantation head shape change is more sensitive to spring stiffness than to the other surgical parameters. However, the overall end-of-treatment head shape is more sensitive to spring positioning and osteotomy size parameters. The results of this work suggest that SAC surgical planning should be performed in view of long-term results, rather than immediate on-table reshaping outcomes.

Dosage-dependent effects of FGFR2W290R mutation on craniofacial shape and cellular dynamics of the basicranial synchondroses

Craniosynostosis is a common yet complex birth defect, characterized by premature fusion of the cranial sutures that can be syndromic or nonsyndromic. With over 180 syndromic associations, reaching genetic diagnoses and understanding variations in underlying cellular mechanisms remains a challenge. Variants of FGFR2 are highly associated with craniosynostosis and warrant further investigation. Using the missense mutation FGFR2W290R , an effective mouse model of Crouzon syndrome, craniofacial features were analyzed using geometric morphometrics across developmental time (E10.5-adulthood, n = 665 total). Given the interrelationship between the cranial vault and basicranium in craniosynostosis patients, the basicranium and synchondroses were analyzed in perinates. Embryonic time points showed minimal significant shape differences. However, hetero- and homozygous mutant perinates and adults showed significant differences in shape and size of the cranial vault, face, and basicranium, which were associated with cranial doming and shortening of the basicranium and skull. Although there were also significant shape and size differences associated with the basicranial bones and clear reductions in basicranial ossification in cleared whole-mount samples, there were no significant alterations in chondrocyte cell shape, size, or orientation along the spheno-occipital synchondrosis. Finally, shape differences in the cranial vault and basicranium were interrelated at perinatal stages. These results point toward the possibility that facial shape phenotypes in craniosynostosis may result in part from pleiotropic effects of the causative mutations rather than only from the secondary consequences of the sutural defects, indicating a novel direction of research that may shed light on the etiology of the broad changes in craniofacial morphology observed in craniosynostosis syndromes.

Papilloedema: a highly specific predictor of raised intracranial pressure in a complex neurosurgical paediatric cohort

PURPOSE

Papilloedema is recognised as an indicator of raised intracranial pressure, although there is a paucity of literature describing the utility of fundoscopy in screening for raised ICP in children with craniofacial synostosis, particularly young children. We sought to investigate the association of optic disc morphology with ICP in children, and to define the sensitivity and specificity of papilloedema as a clinical indicator of raised ICP and determine if age, or underlying conditions impact the findings.

METHOD

Retrospective analysis of all patients undergoing ICP monitoring at a designated paediatric neurosurgical and craniofacial unit in the United Kingdom between October 2009 and October 2018. The fundoscopy findings and ICP monitoring data were analysed for 31 children with craniosynostosis and 29 children without craniosynostosis.

RESULTS

All children who had papilloedema had raised ICP confirmed with monitoring. Across the 60-patient cohort, confirmed papilloedema on fundoscopy had Positive Predictive Value (PPV) of 1.00, Negative Predictive Value (NPV) of 0.64 with sensitivity 48% and specificity 100% for the presence of raised ICP (p =  < 0.0001). In the craniosynostosis group, PPV was 1.00, NPV was 0.39, sensitivity 48% and specificity 100% (p =  < 0.03). There is no correlation between severity of optic disc swelling using Frisen grading and elevation of ICP. Age did not affect the presence of papilloedema in those with raised ICP.

CONCLUSION

The presence of papilloedema is a strong indicator of raised ICP in a child, regardless of underlying aetiology. Detailed fundoscopy can prevent the need for further investigations including imaging-related radiation and invasive CSF pressure monitoring.

Late-Presenting Sagittal Craniosynostosis: An Update to a Standardized Treatment Protocol

BACKGROUND

The authors previously published their protocol to treat patients who present with sagittal craniosynostosis after the age of 1 year. The purpose of this article is to present a follow-up and update of this cohort to evaluate outcomes of their treatment protocol.

METHODS

Patients with isolated sagittal craniosynostosis who presented after the age of 1 year between July of 2013 and April of 2021 were included.

RESULTS

A total of 108 patients met inclusion criteria. The average age at presentation was 5.2 ± 3.4 years, and 79 patients (73.1%) were male. The indications for imaging were head shape (54.6%), headache (14.8%), trauma (9.3%), seizure (4.6%), papilledema (2.8%), and other (13.9%). Of the 108 patients, 12 (11.1%) underwent surgery following their initial consultation: five for papilledema, four for elevated intracranial pressure, two for severely scaphocephalic head shapes, and one for abnormal funduscopic findings. Two of these patients underwent additional reconstructive surgery, one for the recurrence of papilledema and headache and the other for progressive scaphocephaly. The average length of time between operations was 4.9 years. Of the 96 patients who were managed conservatively, four (4.2%) underwent surgery at an average of 1.2 ± 0.5 years later (average age, 4.4 ± 1.5 years) for brain growth restriction ( n = 2), aesthetic concerns ( n = 1), and refractory headaches ( n = 1). The average follow-up of all patients with craniofacial surgery was 2.7 ± 2.3 years (median, 2.1 years; interquartile range, 3.7 years).

CONCLUSIONS

Patients with late-presenting sagittal craniosynostosis require surgical correction less often than younger patients, likely because of milder phenotype. Few patients in the conservative treatment arm ultimately required surgery (4%).

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

A Subdural Hygroma Necessitating a Subdural-Peritoneal Shunt in a Pediatric Patient Following Total Cranial Vault Remodeling Surgery

Sagittal synostosis is a common non-syndromic synostosis treated with open or endoscopic cranial vault remodeling. Early intervention is recommended to avoid restricted brain growth, increased intracranial pressure, and resultant developmental delay. Common complications such as failure or reconstruction, cerebrospinal fluid leak, blood loss, and stroke are well-reported in the literature. Here, we present a rare case of the development of a subdural hygroma following cranial vault remodeling in a seven-month-old male, necessitating the insertion of a subdural-peritoneal shunt.

Flexible endoscope-assisted suture release and barrel stave osteotomy for the correction of sagittal synostosis

OBJECTIVE

Early suturectomy with a rigid endoscope followed by orthotic cranial helmet therapy is an accepted treatment option for single-suture craniosynostosis. To the authors' knowledge, flexible endoscope-assisted suture release (FEASR) has not been previously described. Presented herein is their experience with FEASR for the treatment of isolated sagittal craniosynostosis.

METHODS

A retrospective analysis of the health records of patients who had undergone FEASR between March 2018 and December 2020 was performed. Patients under the age of 6 months who had been diagnosed with isolated sagittal synostosis were considered eligible for FEASR. Exclusion criteria included syndromic synostosis or multiple-suture synostosis. The cephalic index, the primary measure of the cosmetic endpoint, was calculated at prespecified intervals: immediately preoperatively and 6 weeks and 12 months postoperatively. Parental satisfaction with the cosmetic outcome was determined throughout the clinical follow-up and documented according to a structured questionnaire for the first 12 months.

RESULTS

A total of 18 consecutive patients met the criteria for study inclusion. The mean patient age at the time of surgery was 3.4 months (range 2-6 months). All patients underwent a wide craniectomy with no need to convert to an open procedure. The mean craniectomy width was 3.61 cm. Estimated blood loss ranged from 5 to 30 ml. The mean operative time was 75 minutes. No intraoperative complications were observed. The average length of stay was 2.6 days. The mean cephalic index was 67.7 preoperatively, 77.1 at 6 weeks postoperatively, and 76.3 at 1 year postoperatively. The mean percentage change in the cephalic index from preoperatively to the 12-month follow-up was 10.44 (p < 0.001). The mean follow-up was 17 months (range 12-28 months). All parents were satisfied with the cosmetic outcome of the procedure. No patients developed symptoms of raised intracranial pressure (ICP) or needed invasive ICP monitoring during the follow-up period. No patients required reoperation.

CONCLUSIONS

In this modest single-hospital series, the authors demonstrated the feasibility of FEASR in treating sagittal synostosis with favorable cosmetic outcomes. The morbidity profile and resource utilization of the procedure appear similar to those of procedures conducted via traditional rigid endoscopy.

Scaphocephaly and increased intra-cranial pressure in non-operated adults: A controlled anthropological study on 21 skulls

AIM AND SCOPE

The prevalence of increased intra-cranial pressure (ICP) in patients with scaphocephaly is controversial. Here, based on anthropological material, we aimed to determine whether adults with non-operated sagittal synostosis show indirect signs of increased ICP.

MATERIALS AND METHODS

Thirty-eight dry skulls (21 skulls with sagittal craniosynostosis and 17 controls) were selected from the collections of the National Museum of Natural History (Paris, France). All skulls registered as 'fused sagittal suture' or 'scaphocephaly' in the registry of the Museum were included. All had total fusion of the sagittal suture. Controls were selected within skulls of similar origin (France), without visible craniofacial anomalies. The 38 skulls were CT-scanned using a standard medical CT-scan with a protocol dedicated to dry bone imaging. Eight radiological signs associated with raised ICP were assessed: (1) calvaria and (2) skull base thinning, (3) dorsum sellae erosion, (4) sella turcica lengthening, (5) copper beaten skull, (6) suture diastasis, (7) persistent metopic suture, and (8) small frontal sinus. Scaphocephaly was assessed based on head circumference, cranial index, intra-cranial volume, fronto-nasal angle, and inter-zygomatic distance. Linear and non-linear logistic models were used to compare groups.

RESULTS

19/21 skulls with sagittal synostosis were significantly scaphocephalic. None of the criteria for ICP were significantly different in skulls with scaphocephaly relative to controls. Nevertheless, 5 individual skulls with scaphocephaly had ≥ 3 signs in favor of a history of raised ICP. We do not report the significant prevalence of indirect signs of raised ICP in adults with scaphocephaly. These results do not allow ruling out a history of early raised ICP or of minor prolonged raised ICP. Even though our findings support the fact that scaphocephaly is not significantly associated with prolonged raised ICP, individual cases (5/21) with clear signs in favor of a history of brain compression indicate that scaphocephaly correction should be considered as a functional procedure until the production of clear evidence. Cognitive assessments of non-operated adult patients with scaphocephaly could contribute to tackle this recurring question in craniofacial surgery.

Elevated Intracranial Pressure in Patients with Craniosynostosis by Optical Coherence Tomography

BACKGROUND

Craniosynostosis may lead to elevated intracranial pressure, which may be implicated with impaired neurocognitive development. However, accurately measuring intracranial pressure is challenging, and patterns in craniosynostosis patients are poorly characterized. Spectral-domain optical coherence tomography may enable noninvasive assessment of intracranial pressure in pediatric patients with craniosynostosis.

METHODS

Pediatric patients with craniosynostosis undergoing surgical intervention between 2014 and 2019 prospectively underwent optical coherence tomographic evaluation. Intracranial pressure was directly measured intraoperatively in a subset of cases. Optical coherence tomographic parameters were compared to directly measured intracranial pressure and used for pattern assessment.

RESULTS

Optical coherence tomography was performed in 158 subjects, among which 42 underwent direct intracranial pressure measurement during an initial cranial procedure. Maximal retinal nerve fiber layer thickness, maximal retinal thickness, and maximal anterior projection optical coherence tomographic parameters were positively correlated with intracranial pressure (p ≤ 0.001), with all parameters showing significantly higher values in patients with intracranial pressure thresholds of 15 mmHg (p < 0.001) and 20 mmHg (p ≤ 0.007). Patients with maximal retinal nerve fiber layer thickness and maximal anterior projection exceeding set thresholds in optical coherence tomography of either eye demonstrated 77.3 percent sensitivity and 95.0 percent specificity for detecting intracranial pressure above 15 mmHg, and 90.0 percent sensitivity and 81.3 percent specificity for detecting intracranial pressure above 20 mmHg. Patients with associated syndromes or multiple suture involvement and patients aged 9 months or older were significantly more likely to have elevated intracranial pressure above 15 mmHg (p ≤ 0.030) and above 20 mmHg (p ≤ 0.035).

CONCLUSIONS

Spectral-domain optical coherence tomography can noninvasively detect elevated intracranial pressure in patients with craniosynostosis with reliable sensitivity and specificity. This technology may help guide decisions about the appropriate type and timing of surgical treatment.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, I.

Intraoperative Measurement of Intracranial Pressure During Cranial Vault Remodeling in Children with Craniosynostosis

Purpose  In this study, we analyzed the utility of intracranial pressure (ICP) monitoring intraoperatively for deciding height reduction and need for cerebrospinal fluid (CSF) diversion during cranial vault remodeling in children with multisutural craniosynostosis (CS).

Methods  This is a retrospective observational study of children who underwent surgery for CS and ICP monitoring during surgery. The ICP was monitored using an external ventricular drainage catheter. The ICP monitoring was continued during the entire procedure.

Results  A total of 28 (19 boys) children with the involvement of two or more sutures underwent ICP monitoring during surgery. The commonest pattern of suture involvement was bicoronal seen in 16 (57.1%) children followed by pancraniosynostoses in eight (28.6%) cases. The mean opening ICP was 23 mm Hg, which dropped to 10.9 mm Hg after craniotomy. The ICP increased transiently to 19.5 mm Hg after height reduction, and the mean ICP at closure was 16.2 mm Hg. The ICP recordings helped in undoing the height reduction in two children and ventriculoperitoneal shunt after surgery in two children.

Conclusions  Intraoperative monitoring of ICP helps in deciding the type of cranial vault remodeling and the need for CSF diversion after surgery.

The use of OCT to detect signs of intracranial hypertension in patients with sagittal suture synostosis: Reference values and correlations

PURPOSE

To obtain pediatric normative reference values and determine whether optical coherence tomography (OCT) corresponds better with clinical signs of intracranial hypertension (ICH) compared to the traditional screening method fundoscopy in a large cohort of one type of single suture craniosynostosis.

METHODS

Control subjects without optic nerve diseases and isolated sagittal synostosis patients aged 3-10 years who underwent fundoscopy and OCT were included in this prospective cohort study. Normative reference values were obtained through bootstrap analysis. Main outcome was the association between peripapillary total retinal thickness (TRT) and total retinal volume (TRV) and appearance on fundoscopy. Signs and symptoms suggestive of ICH, including skull growth arrest, fingerprinting, and headache, were scored.

RESULTS

Sixty-four healthy controls and 93 isolated sagittal synostosis patients were included. Normative cut-off values for mean TRT are < 256 μm and > 504 μm and for mean TRV < 0.21 mm³ and > 0.39 mm³. TRT was increased in 16 (17%) and TRV in 15 (16%) of 93 patients, compared to only 4 patients with papilledema on fundoscopy (4%). Both parameters were associated with papilledema on fundoscopy (OR = 16.7, p = 0.02, and OR = 18.2, p = 0.01). Skull growth arrest was significantly associated with abnormal OCT parameters (OR = 13.65, p < 0.01).

CONCLUSIONS

The established cut-off points can be applied to screen for ICH in pediatrics. The present study detected abnormalities with OCT more frequent than with fundoscopy, which were associated with skull growth arrest. Therefore, a combination of OCT, fundoscopy, and skull growth arrest can improve clinical decision-making in craniosynostosis.

Elevated intracranial pressure with craniosynostosis: a multivariate model of age, syndromic status, and number of involved cranial sutures

OBJECTIVE

Children with multiple prematurely fused cranial sutures and those undergoing surgical correction later in life appear to experience worse neurocognitive outcomes, but it is unclear whether higher intracranial pressure (ICP) is implicated in this process. The purpose of this study was to elucidate the effect of age at intervention and number of involved cranial sutures on ICP, as well as to assess which cranial suture closure may be more associated with elevated ICP.

METHODS

The prospective craniofacial database at the authors' institution was queried for patients undergoing initial corrective surgery for craniosynostosis in whom intraoperative measurement of ICP was obtained prior to craniectomy. Age, involved sutures, and syndromic status were analyzed in the context of measured ICP by using multiple linear regression.

RESULTS

Fifty patients met the inclusion criteria. Age at procedure (p = 0.028, β = +0.060 mm Hg/month) and multiple-suture involvement (p = 0.010, β = +4.175 mm Hg if multisuture) were both significantly implicated in elevated ICP. The actual number of major sutures involved was significantly correlated to ICP (p = 0.001; β = +1.687 mm Hg/suture). Among patients with single-suture involvement, there was an overall significant difference of median ICP across the suture types (p = 0.008), with metopic having the lowest (12.5 mm Hg) and sagittal having the highest (16.0 mm Hg). Patients with multiple-suture involvement had significantly higher ICP (p = 0.003; 18.5 mm Hg). Patients with craniofacial syndromes were 79.3 times more likely to have multiple-suture involvement (p < 0.001). Corrective surgery for craniosynostosis demonstrated significant intraoperative reduction of elevated ICP (all p < 0.050).

CONCLUSIONS

Syndromic status, older age at intervention for craniosynostosis, and multiple premature fusion of cranial sutures were associated with significantly higher ICP.

Craniosynostosis Surgery for Increased Intracranial Pressure

INTRODUCTION

Craniosynostosis is the premature fusion of 1 or more cranial sutures. The presentation may vary, and there are differing opinions regarding surgical indications and timing. Though increased intracranial pressure (ICP) is a well-established risk of craniosynostosis, its response to treatment is not uniform. This study aims to identify the signs and symptoms indicative of increased ICP that are most likely to improve after craniosynostosis surgery.

METHODS

Pre- and post-operative data were retrospectively collected from patients at our institution with syndromic and non-syndromic craniosynostosis from January 2009 to June 2020. Demographics, symptoms (headache, nausea, emesis, and lethargy), signs (visual disturbances and papilledema), and imaging characteristics (copper beaten changes), if available, were analyzed.

RESULTS

One hundred fifty-three children with craniosynostosis were identified, and 56 with preoperative symptoms met inclusion criteria. Older age was significantly correlated with the number of symptoms improved postoperatively (P = 0.015). Papilledema, headache, nausea, and irritability (if present preoperatively) were the features most likely to improve after craniosynostosis repair. Optic nerve or disc anomalies, feeding difficulties, seizures, and need for glasses were least likely to improve.

CONCLUSIONS

Older children undergoing craniosynostosis surgery had a greater number of improved symptoms. Classical features of increased ICP were more likely to improve than developmental difficulties and multifactorial causes. These findings may be useful when considering craniosynostosis repair in a symptomatic child.

Giant pattern VEPs in children

Our aim is to elaborate the clinical significance of giant amplitude pattern reversal visual evoked potentials (VEPs) in children. 'Giant' amplitude VEPs exceed the upper 97.5^th centile, 90% CI for age. We scrutinised 2750 pattern VEPs recorded to international standards between Jan 2015 and 2017 from children aged 16 years and under, attending a specialist children's hospital. Twenty seven children, median age 6yrs, (range 1-16 yrs), were identified with giant VEPs (P100 amplitude range 65-163 μV). Most, 22/27 (81%), had conditions associated with a risk of raised ICP. Sixteen of these twenty two children had craniosynostosis; six multi-sutural and eight single suture disease. Others had Idiopathic Intracranial Hypertension, arachnoid cyst, NF1 with shunted hydrocephalus, chronic infantile neurological cutaneous and articular (CINCA) syndrome, nephrotic cystinosis and obstructive sleep apnoea. Five children presented with a range of conditions, some associated with seizures some symptomatic, but as yet undiagnosed. Frequent structural associations were optical coherence tomography measures of optic disc maximum anterior axial horizontal retinal thickness projection >160 μm and neuro-radiological findings of CSF effacement and copper beaten appearance. Ultrasonography measures of optic nerve sheath diameters varied, but in one child took 2 years to resolve after treatment for raised ICP. Optic disc gradings by fundoscopy were mostly normal, as were visual acuities. Raised ICP was confirmed by gold standard ICP bolt measurements in five of seven children tested. These data suggest that rICP should be considered if a child has sustained giant amplitude VEPs at normal latency.

Non-traumatic pediatric intracranial hypertension: key points for different etiologies, diagnosis, and treatment

Intracranial hypertension can be an acute life-threatening event or slowly deteriorating condition, leading to a gradual loss of neurological function. The diagnosis should be taken in a timely fashioned process, which mandates expedite measures to save brain function and sometimes life. An optimal management strategy is selected according to the causative etiology with a core treatment paradigm that can be utilized in various etiologies. Distinct etiologies are intracranial bleeds caused by traumatic brain injury, spontaneous intracranial hemorrhage (e.g., neonatal intraventricular hemorrhage), or the rare pediatric hemorrhagic stroke. The other primary pediatric etiologies for elevated intracranial pressure are intracranial mass (e.g., brain tumor) and hydrocephalus related. Other unique etiologies in the pediatric population are related to congenital diseases, infectious diseases, metabolic or endocrine crisis, and idiopathic intracranial pressure. One of the main goals of treatment is to alleviate the growing pressure and prevent the secondary injury to brain parenchyma due to inadequate blood perfusion and eventually inadequate parenchymal oxygenation and metabolic state. Previous literature discussed essential characteristics of the treatment paradigm derived mainly from pediatric brain traumatic injuries' treatment methodology. Yet, many of these etiologies are not related to trauma; thus, the general treatment methodology must be tailored carefully for each patient. This review focuses on the different possible non-traumatic etiologies that can lead to intracranial hypertension with the relevant modification of each etiology's treatment paradigm based on the current literature.

Pre-operative imaging and post-operative appearance of standard paediatric neurosurgical approaches: a training guide for neuroradiologists

A short-cut narrative review was conducted according to the SANRA guidelines to identify studies describing normal and abnormal postoperative radiological features of the most common paediatric neurosurgical procedures. Rather than focusing on the original pathology addressed by neurosurgical means, this review explored three main areas of operative neurosurgery: ventricular access, supratentorial & infratentorial craniotomies, and posterior fossa/craniocervical junction decompression. A total of twenty-three landmark papers were included for review based on their relevance to address the research question and serve as a practical guide for paediatric neuroradiology trainees and fellows. Accurate in text referencing of the ClinicalTrials.gov identifier, and weblink, has also been provided for all trials discussed in the results section. All the above is complemented by relevant iconography meant to describe a wide range of postoperative changes and early complications. Finally, the review is enriched by a discussion touching upon haemostatic agents, intentionally retained foreign bodies and the future of machine learning for neuroradiology reporting. Overall, the information presented in a systematic fashion will not only help trainees and fellows to deepen these topics and expand their knowledge in preparation for written and oral boards, but will also represent a useful resource for everyone including trained neuroradiologists and neurosurgeons themselves.

Early Recognition of Raised Intracranial Pressure in Craniosynostosis Using Optical Coherence Tomography

OBJECTIVE

Craniosynostosis can be associated with raised intracranial pressure (ICP), which can pose deleterious effects on the brain and vision if untreated. Estimating ICP in children is challenging, whilst gold standard direct intracranial measurement of ICP is invasive and carries risk. This systematic review aims to evaluate the role of optical coherence tomography (OCT), a noninvasive imaging technique, for detecting raised ICP in children with craniosynostosis.

METHODS

The authors conducted a systematic review of the literature published from inception until 19 August, 2019 in the Cochrane Central Register of Controlled Trials, PubMed, MEDLINE, and EMBASE. Eligible studies evaluated the role of OCT in detecting raised ICP in children aged 0 to 16 years with craniosynostosis. Main outcome measures were sensitivity and specificity of OCT parameters for raised ICP. Quality assessment was performed using the National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-sectional Studies.

RESULTS

Out of 318 records identified, data meeting the inclusion criteria were obtained from 3 studies. The quality of 2 studies was poor whilst 1 was fair. Optical coherence tomography demonstrated higher sensitivity and specificity for detecting raised ICP compared to fundus examination, clinical history, radiological testing, and visual field testing.

CONCLUSIONS

This systematic review demonstrated a lack of quality evidence for OCT as a screening tool for children with craniosynostosis. Further research is required to clarify the strength of OCT in this role and to determine which OCT parameters are most appropriate.

Comparison of 2 Sagittal Craniosynostosis Repair Techniques: Spring-Assisted Surgery Versus Endoscope-Assisted Craniectomy With Helmet Molding Therapy

INTRODUCTION

This study compares anthropometric outcomes of 2 sagittal synostosis repair techniques: spring-assisted surgery and endoscope-assisted craniectomy with molding helmet therapy.

METHODS

Patients undergoing spring-assisted surgery (n = 27) or endoscope-assisted craniectomy with helmet therapy (n = 40) at separate institutions were retrospectively reviewed. Pre- and 1-year postoperative computed tomography (CT) or laser scans were analyzed for traditional cranial index (CI), adjusted cranial index (aCI), and cranial vault volume (CVV). Nine patient-matched scans were analyzed for measurement consistency.

RESULTS

The spring-assisted group was older at both time points (P < .050) and spring-assisted group CVV was larger preoperatively and postoperatively (P < .01). However, the change in CVV did not differ between the groups (P = .210). There was no difference in preoperative CI (helmet vs spring: 70.1 vs 71.2, P = .368) between the groups. Postoperatively, helmet group CI (77.0 vs 74.3, P = .008) was greater. The helmet group also demonstrated a greater increase in CI (6.9 vs 3.1, P < .001). The proportion of patients achieving CI of 75 or greater was not significantly different between the groups (helmet vs spring: CI, 65% vs 52%, P = .370). There was no detectable bias in CI between matched CT and laser scans. Differences were identified between scan types in aCI and CVV measurements; subsequent analyses used corrected CVV and aCI measures for laser scan measures.

CONCLUSIONS

Both techniques had equivalent proportions of patients achieving normal CI, comparable effects on cranial volume, and similar operative characteristics. The study suggests that there may be greater improvement in CI in the helmet group. However, further research should be performed.

Occult Scaphocephaly: A Forme Fruste Phenotype of Sagittal Craniosynostosis

INTRODUCTION

Latent cranial suture fusions may present with mild or absent phenotypic changes that make the clinical diagnosis challenging. Recent reports describe patients with sagittal synostosis and a normal cranial index (CI), a condition termed normocephalic sagittal craniosynostosis (NSC). The goal of this study is to evaluate the shape and intracranial volume (ICV) in a cohort of NSC patients using quantitative cranial shape analysis (CSA).

METHODS

We identified 19 patients (7.5 ± 2.28 years) between 2011 and 2016, who presented to our hospital with NSC. Cranial index and CSA were measured from the computed tomography image. Cranial shape analysis calculates the distances between the patient's cranial shape and its closest normal shape. Intracranial volume was measured and compared to an established age-matched normative database.

RESULTS

Cranial index revealed 15 (78.9%) patients within the mesocephalic range and 4 patients (21.1%) in the brachycephalic range. Detailed CSA identified 15 (78.9%) patients with subtle phenotypic changes along the scaphocephalic spectrum (ie, subtle anterior and posterior elongation with inter-parietal narrowing) and 1 patient (5.3%) with isolated overdevelopment on the posterior part of the right parietal bone. Three patients (15.8%) had a CSA close to normal. Mean ICV was 1410.5 ± 192.77cc; most patients (78.9%) fell within ±2 standard deviations.

CONCLUSION

Quantitative CSA revealed that most of the patients with NSC had cranial shape abnormalities, consistent with a forme fruste scaphocephaly that could not be otherwise recognized by clinical observation or CI. Given these findings, we propose the term occult scaphocephaly to describe this condition. The associated incidence of intracranial hypertension is unknown.

Intracranial pressure, brain morphology and cognitive outcome in children with sagittal craniosynostosis

BACKGROUND

Patients with sagittal craniosynostosis are at increased risk of developing raised intracranial pressure (ICP) and neurocognitive deficiencies such as reduced attention, planning, speech, behavioural and learning disabilities.

AIM

To determine if the existing literature supports a correlation between elevated ICP and negative cognitive outcome in patients with sagittal craniosynostosis. Secondly, to investigate if the risk of developing neurocognitive deficiencies can be explained by changes in brain morphology in this patient category.

METHODS

Systematic literature review in PubMed.

RESULTS

A total of 190 publications were reviewed to determine a possible correlation between raised ICP and cognitive outcome, of which four were included in the study. No significant association was found. Forty-four publications on brain morphology in sagittal craniosynostosis were identified, of which 11 were included in the review. Clear evidence of morphologic changes in multiple areas of the brains of sagittal craniosynostosis patients was found in the literature.

CONCLUSION

The existing literature does not support an association between increased ICP and negative global cognitive outcome measures in patients with sagittal craniosynostosis. Brain morphology is altered in areas related to neurocognition and language in the same patient group. These changes might play a role in the development of neurocognitive deficiencies, though no definitive link is yet established, and further investigation is warranted.

Intracranial pressure patterns in children with craniosynostosis utilizing optical coherence tomography

BACKGROUND

Better understanding the incidence and patterns of elevated intracranial pressure (ICP) in patients with craniosynostosis may facilitate more timely intervention to alter neurocognitive outcomes. Spectral-domain optical coherence tomography (OCT) of the retina can non-invasively diagnose elevated ICP, and has demonstrated high sensitivity and specificity among patients with craniosynostosis. This study sought to characterize patterns of elevated ICP among patients with craniosynostosis.

METHODS

Quantitative retinal parameters were prospectively assessed in both eyes of patients with craniosynostosis using spectral-domain OCT. Based on retinal OCT thresholds associated with elevated ICP (> 15 mmHg), subjects were assigned an OCT diagnosis of elevated or non-elevated ICP which was analyzed relative to clinical characteristics and craniosynostosis patterns.

RESULTS

Eighty subjects (aged 0.2-18 years) with craniosynostosis were enrolled; among these, 67 (84%) were nonsyndromic. OCT evaluation was performed at initial vault expansion in 56 (70%) patients. Among this subset, 27 (48%) patients had peri-papillary changes suggestive of elevated ICP, reflecting a 44% incidence in nonsyndromic and 83% in syndromic patients. The median age at initial vault expansion was higher among those with elevated ICP (11.1 months) than those without (7.8 months; p = 0.04.) Multi-suture synostosis was associated with changes consistent with elevated ICP in 9 (75%) patients compared with 18 (41%) with single suture synostosis (p = 0.05).

CONCLUSIONS

OCT of the retina produces a potentially sensitive indicator of ICP in craniosynostosis patients. Elevated ICP may be associated with number of involved sutures and older patient presentation, and refining appropriate "cutoffs" will be important as the technology becomes more widespread.

A systematic quantitative morpho-volumetric analysis in infants with sagittal craniosynostosis and relationship with the severity of scaphocephalic deformity

PURPOSE

Among patients with isolated sagittal synostosis (ISS), the head shape varies considerably in relation to the severity of the abnormality. This study aimed to quantify skull base morphometry and intracranial volume to investigate their relationships with the severity of scaphocephaly.

METHODS

We studied 66 infants with ISS identifying three groups according to the morphological severity of cranial deformity (group I: mild deformity; group II: moderate deformity; group III: severe deformity), by combining two scaphocephaly severity indices as descriptors of the relation of three morphological measurements (length, width and height) We perform a quantitative analysis using high-resolution CT images calculating following parameters: cranial fossae dimensions, supratentorial (ICV) and infratentorial (PCFV) cranial volume, supratentorial (WBV) and infratentorial (PCFBV) brain volume, ICV/WBV, PCFV/PCFBV, supratentorial and infratentorial cerebrospinal fluid (CSF).

RESULTS

In all subgroups, anterior and middle skull base lengths were increased, while posterior hemifossae lengths were unchanged. In mild subgroup, ICV/WBV was significantly different and ICV, WBV and CSF supratentorial volume increased (p < 0.05). In moderate and severe subgroups, FCPV/FCPBV was significantly different and CSF infratentorial volume was reduced (p < 0.05); FCPBV was increased only in the severe subgroup (p < 0.05).

CONCLUSION

This morpho-volumetric study provides new insights in understanding the compensatory changes occurring in infants at different stages of scaphocephaly severity. In particular, our study suggests that patients with severe deformity might have an earlier depletion of reserve mechanisms with a reduced compliance of the overall skull during encephalic growth and these patients might require early surgical cranial expansion.

A population-specific material model for sagittal craniosynostosis to predict surgical shape outcomes

Sagittal craniosynostosis consists of premature fusion (ossification) of the sagittal suture during infancy, resulting in head deformity and brain growth restriction. Spring-assisted cranioplasty (SAC) entails skull incisions to free the fused suture and insertion of two springs (metallic distractors) to promote cranial reshaping. Although safe and effective, SAC outcomes remain uncertain. We aimed hereby to obtain and validate a skull material model for SAC outcome prediction. Computed tomography data relative to 18 patients were processed to simulate surgical cuts and spring location. A rescaling model for age matching was created using retrospective data and validated. Design of experiments was used to assess the effect of different material property parameters on the model output. Subsequent material optimization-using retrospective clinical spring measurements-was performed for nine patients. A population-derived material model was obtained and applied to the whole population. Results showed that bone Young's modulus and relaxation modulus had the largest effect on the model predictions: the use of the population-derived material model had a negligible effect on improving the prediction of on-table opening while significantly improved the prediction of spring kinematics at follow-up. The model was validated using on-table 3D scans for nine patients: the predicted head shape approximated within 2 mm the 3D scan model in 80% of the surface points, in 8 out of 9 patients. The accuracy and reliability of the developed computational model of SAC were increased using population data: this tool is now ready for prospective clinical application.

The economic impact of open versus endoscope-assisted craniosynostosis surgery

OBJECTIVE

Open and endoscope-assisted repair are surgical options for sagittal craniosynostosis, with limited research evaluating each technique's immediate and long-term costs. This study investigates the cost-effectiveness of open and endoscope-assisted repair for single, sagittal suture craniosynostosis.

METHODS

The authors performed a retrospective cohort study of patients undergoing single, sagittal suture craniosynostosis repair (open in 17 cases, endoscope-assisted in 16) at less than 1 year of age at Monroe Carell Jr. Children's Hospital at Vanderbilt (MCJCHV) between August 2015 and August 2017. Follow-up data were collected/analyzed for 1 year after discharge. Surgical and follow-up costs were derived by merging MCJCHV financial data with each patient's electronic medical record (EMR) and were adjusted for inflation using the healthcare Producer Price Index. Proxy helmet costs were derived from third-party out-of-pocket helmet prices. To account for variable costs and probabilities, overall costs were calculated using TreeAge tree diagram software.

RESULTS

Open repair occurred in older patients (mean age 5.69 vs 2.96 months, p < 0.001) and required more operating room time (median 203 vs 145 minutes, p < 0.001), more ICU days (median 3 vs 1 day, p < 0.001), more hospital days (median 4 vs 1 day, p < 0.001), and more frequently required transfusion (88% vs 6% of cases). Compared to patients who underwent open surgery, patients who underwent endoscopically assisted surgery more often required postoperative orthotic helmets (100% vs 6%), had a similar number of follow-up clinic visits (median 3 vs 3 visits, p = 0.487) and CT scans (median 3 vs 2 scans), and fewer emergency department visits (median 1 vs 3 visits). The TreeAge diagram showed that, overall, open repair was 73% more expensive than endoscope-assisted repair ($31,314.10 vs $18,081.47). Sensitivity analysis identified surgical/hospital costs for open repair (mean $30,475, SEM $547) versus endoscope-assisted repair (mean $13,746, SEM $833) (p < 0.001) as the most important determinants of overall cost. Two-way sensitivity analysis comparing initial surgical/hospital costs confirmed that open repair remains significantly more expensive under even worst-case initial repair scenarios ($3254.81 minimum difference). No major surgical complications or surgical revisions occurred in either cohort.

CONCLUSIONS

The results of this study suggest that endoscope-assisted craniosynostosis repair is significantly more cost-effective than open repair, based on markedly lower costs and similar outcomes, and that the difference in initial surgical/hospital costs far outweighs the difference in subsequent costs associated with helmet therapy and outpatient management, although independent replication in a multicenter study is needed for confirmation due to practice and cost variation across institutions. Longer-term results will also be needed to examine whether cost differences are maintained.

Intracranial volume versus static and pulsatile intracranial pressure values in children with craniosynostosis

OBJECTIVE

Reduced intracranial volume (ICV) and raised intracranial pressure (ICP) are assumed to be principal pathophysiological mechanisms in childhood craniosynostosis. This study examined the association between ICV and ICP and whether ICV can be used to estimate the ICP.

METHODS

The authors analyzed ICV and ICP measurements from children with craniosynostosis without concurrent hydrocephalus and from age-matched individuals without craniosynostosis who underwent diagnostic ICP measurement.

RESULTS

The study included 19 children with craniosynostosis (mean age 2.2 ± 1.9 years) and 12 reference individuals without craniosynostosis (mean age 2.5 ± 1.6 years). There was no difference in ICV between the patient and reference cohorts. Both mean ICP (17.1 ± 5.6 mm Hg) and mean wave amplitude (5.9 ± 2.6 mm Hg) were higher in the patient cohort. The results disclosed no significant association between ICV and ICP values in the patient or reference cohorts, and no association was seen between change in ICV and ICP values after cranial vault expansion surgery (CVES) in 5 children in whom ICV and ICP were measured before and after CVES.

CONCLUSIONS

In this cohort of children with craniosynostosis, there was no significant association between ICV and ICP values prior to CVES and no significant association between change in ICV and ICP values after CVES in a subset of patients. Therefore, ICV could not reliably estimate the ICP values. The authors suggest that intracranial hypertension in childhood craniosynostosis may not be caused by reduced ICV alone but rather by a distorted relationship between ICV and the volume of intracranial content (brain tissue, CSF, and blood).

A comparison of endoscopic strip craniectomy and pi craniectomy for treatment of sagittal craniosynostosis

OBJECTIVE

Sagittal craniosynostosis is managed with a wide variety of operative strategies. The current investigation compares the clinical outcomes of two widely performed techniques: pi craniectomy and minimally invasive endoscopic strip craniectomy (ESC) followed by helmet therapy.

METHODS

This IRB-approved retrospective study examined patients diagnosed with nonsyndromic, single-suture sagittal craniosynostosis treated with either pi craniectomy or ESC. Included patients had a minimum postoperative follow-up of 5 months.

RESULTS

Fifty-one patients met the inclusion criteria (pi 21 patients, ESC 30 patients). Compared to patients who underwent ESC, the pi patients were older at the time of surgery (mean age 5.06 vs 3.11 months). The mean follow-up time was 23.2 months for ESC patients and 31.4 months for pi patients. Initial cranial index (CI) was similar between the groups, but postoperatively the ESC patients experienced a 12.3% mean increase in CI (from 0.685 to 0.767) compared to a 5.34% increase for the pi patients (from 0.684 to 0.719), and this difference was statistically significant (p < 0.001). Median hospital length of stay (1 vs 2 days) and operative duration (69.5 vs 93.3 minutes) were significantly less for ESC (p < 0.001 for both). The ESC patients showed a trend toward better results when surgery was done at younger ages. Craniectomy width in ESC cases was positively associated with CI improvement (slope of linear regression = 0.69, p = 0.026).

CONCLUSIONS

While both techniques effectively treated sagittal craniosynostosis, ESC showed superior results compared to pi craniectomy. ESC showed a trend for better outcomes when done at younger ages, although the trend did not reach statistical significance. A wider craniectomy width (up to 2 cm) was associated with better outcomes than smaller craniectomy widths among the ESC patients.

The Incidence of Chiari Malformations in Patients with Isolated Sagittal Synostosis

Background:

We report the incidence of Chiari malformation I (CMI) in a cohort of 377 patients with isolated sagittal synostosis (ISS), which is to the best of our knowledge the largest such series reported to date.

Methods:

A retrospective review of patients seen at a single institution from 2007 to 2017 was completed. ISS, Chiari malformations (CMI and CMII) and hydrocephalus were diagnosed by a senior neuroradiologist (G.Z.). Patients who met the inclusion criteria were divided into early (group A) and late (group B) presenting groups, as well as operated (group I) and unoperated (group II) groups. The patients were further subdivided into group AI (early operated), group AII (early unoperated), group BI (late operated), and group BII (late unoperated). Once identified, patient notes were examined for the following data sets: date of birth, age of presentation, age at last follow-up, other systemic conditions as well as molecular testing results. Surgical interventions, ophthalmological, and other relevant data were recorded. Statistical analysis was run in the form of a chi-square test to identify a significant difference between each subgroup. A literature review of the incidence of Chiari malformations in patients with ISS was conducted.

Results:

Three hundred seventy-seven patients constitute the study’s total cohort (272 were males and 105 females). This cohort was divided into patients who underwent surgical repair of ISS (group 1: n = 200), and patients who did not (group 2: n = 177). The entire cohort was also divided into early (group A: n = 161) and late (group B: n = 216) presenting craniosynostosis. In the total cohort, 22/377 (5.8%) patients with CMI were identified. CMI was found in 14/200 (7.0%) patients in group I, and 8/177 (4.5%) patients in group II. CMI was found in 2/161 (1%) patients in group A, and 20/216 (9.2%) patients in group B. The incidence of CMI in group AI (early operated) was 2/151 (1.3%), in group AII (early unoperated) was 0/10, in group BI (late operated) was 11/49 (21%), and in group BII (late unoperated) was 9/167 (5.4%). Chi-square analysis revealed a significant difference between the incidence of CMI in the early-presenting (group A) and late-presenting (group B) groups (P = 0.001) and between the late-presenting operated (BI) and late-presenting unoperated (BII) groups (P = 0.001). The incidence of hydrocephalus was 1.6% (6/377) in the total cohort. However, all patients diagnosed with hydrocephalus came from group II (no surgical ISS correction). The incidence of hydrocephalus in group II was 3.3% (6/177). The incidence of hydrocephalus in group BII (late unoperated ISS) was 3.0% (5/167). The incidence of hydrocephalus in group AII (early unoperated ISS) was 9.0% (1/11).

Conclusions:

We noted the highest incidence of CMI—21%—in group BI (late-presenting operated). We noted hydrocephalus in group II (nonoperated), with the highest incidence of hydrocephalus found in the group BII (late-presenting unoperated) subgroup. We therefore recommend patients with ISS receive funduscopic examination to screen for raised intracranial pressure (ICP) associated with CMI and hydrocephalus, especially patients with late-presenting ISS.

Practical Computed Tomography Scan Findings for Distinguishing Metopic Craniosynostosis from Metopic Ridging

Background:

Premature fusion of the metopic suture (ie, metopic craniosynostosis) can be difficult to discriminate from physiological closure of the metopic suture with ridging (MR). Yet, MCS is treated surgically, whereas MR is treated nonsurgically. Often, the diagnosis can be made by physical examination alone, but in difficult cases, a computed tomography (CT) scan can add additional diagnostic information.

Methods:

We de-identified, randomized, and analyzed the CT scans of patients with MCS (n = 52), MR (n = 20) and age-matched normative controls (n = 52) to identify specific findings helpful in distinguishing between MCS and MR. Four expert clinicians were blinded to the clinical diagnosis and assessed each CT for features of the orbits, frontal bones, and inner table of calvaria.

Results:

Although no single feature was diagnostic of MCS, we identified several signs that were correlated with MCS, MR, or controls. Features such as “posteriorly displaced frontal bone” and “frontal bone tangent to mid-orbit or medial” demonstrated higher correlation with MCS than MR and the addition of other features improves the accuracy of diagnosis as did inclusion of the interfrontal divergence angle.

Conclusion:

The presence of a closed metopic suture in addition to other CT scan findings may improve the accuracy of diagnosing MCS, MR, and normocephaly.

Intracranial volume (ICV) in isolated sagittal craniosynostosis: a retrospective case-matched-control study

PURPOSE

Children with sagittal craniosynostosis (SC) are at risk of developing raised intracranial pressure (ICP). This is thought to result from cephalocranial disproportion-the restriction of normal cerebral development by a small cranial vault. It remains unclear whether intracranial volume (ICV) is altered in SC. This study offers a novel volumetric analysis of the scaphocephalic skull, comparing supratentorial (ST) volume, infratentorial (IT) volume, and total ICV of patients with sagittal synostosis to normal controls.

METHODS

ICVs of 32 consecutive patients undergoing total calvarial vault remodelling (TCVR) for isolated SC were compared to 32 age- and sex-matched normal controls. ICV was measured with manual techniques on head computerised tomographic (CT) scans using OsiriX software. A paired t test was used to compare data between cases and controls.

RESULTS

Mean total ICV, ST volume and IT volume were larger in SC than in controls, except in females > 6 months of age. There was no statistical significance. Regression analysis demonstrated larger ICVs in diseased children than in controls younger than 10 months, at which age trend lines intersected and the reverse became true for older children. This likely represents an evolving risk of cephalocranial disproportion beyond 10 months of age. The IT/ST volume ratio was conserved in scaphocephaly, and very closely approximated that of controls.

CONCLUSIONS

Sagittal craniosynostosis appears to be associated with a larger cranial vault at less than 10 months and a smaller vault at greater than 10 months, although statistical significance was not achieved.

Physiologic closure time of the metopic suture in South Australian infants from 3D CT scans

Metopic synostosis is a craniofacial condition characterised by the premature fusion of the metopic suture. This early fusion restricts frontal bone growth [17] and has significant impacts on the developing infant during a critical phase of rapid growth and development [4]. Diagnosis of the condition is usually achieved by clinical assessment, followed by a three-dimensional computed tomography (3D CT) scan, verifying premature metopic suture fusion.

PURPOSE

This retrospective study aims to investigate the timing of metopic suture fusion in the developing infant in an Australian subpopulation.

METHODS

The study evaluates metopic suture fusion in 258 cranial 3D CT scans of children aged 0-24 months over a 5-year period (2011-2016), scanned at Women's and Children's Hospital.

RESULTS

The findings suggest that the age range over which physiologic metopic suture fusion occurs is larger than previously reported.

CONCLUSIONS

The approximate range for physiologic fusion was found to be 3-19 months and patients with fusion within this range can be considered normal. Complete suture fusion is expected by 19 months. Additionally, results indicate suture fusion prior to 3 months is abnormal and diagnostically indicative of metopic synostosis.

Short- and Long-Term Outcomes by Procedure Type for Nonsagittal Single-Suture Craniosynostosis

BACKGROUND

Minimally invasive approaches for the treatment of single-suture craniosynostosis are sometimes touted as equivalent to cranial vault reconstruction. While techniques for sagittal synostosis have been reviewed previously, evidence regarding open and less invasive surgical techniques for metopic, coronal, and lambdoid synostosis has yet to be reviewed.

METHODS

Systematic searches were performed using Embase.com and PubMed. Included studies reported short- or long-term outcomes, compared at least 2 standard techniques, discussed single-suture coronal, metopic, or lambdoid craniosynostosis, and enrolled at least 20 study participants. Two authors screened titles and abstracts, and also performed full text review and data extraction. Given heterogeneous outcomes, qualitative synthesis was performed after data extraction.

RESULTS

The search strategy yielded 2348 articles. Of these, 313 were removed as duplicates, and 1935 were excluded during title/abstract review. After full text review of 100 articles, 19 were selected for data extraction. The heterogeneity of outcomes precluded meta-analysis and required qualitative synthesis. While short-term outcomes indicated decreased morbidity of minimally invasive techniques, only 2 articles presented long-term reoperation rates. One study reported higher reoperation rates in the less invasive technique, and the second reported no reoperations in the median follow-up period of 33 months.

CONCLUSION

Studies comparing long-term outcomes between different surgical techniques for single-suture craniosynostosis remain deficient. The development of standardized outcome measures is essential, and prospective, multicenter studies are necessary to assess the long-term efficacy of these procedures.

Analysis of clinical outcomes for treatment of sagittal craniosynostosis: a comparison of endoscopic suturectomy and cranial vault remodeling

The authors compared the effectiveness of two main surgical techniques used for treating sagittal craniosynostosis (SC): endoscopic suturectomy (ES) and cranial vault remodeling (CVR). The safety, head growth, and aesthetic results following ES and CVR were compared by reviewing the charts of more than 200 patients. By comparing the effectiveness of these two treatments, this study will help guide selection of the optimal surgical treatment for patients with SC.

Subjective Assessment of Head and Facial Appearance in Children with Craniosynostoses after Surgical Treatment

BACKGROUND

Craniosynostoses are congenital defects in the construction of the skull involving premature fusion of one or more cranial sutures. Premature fusion of sutures causes characteristic skull deformation(s). This affect the structure and thus the appearance of the entire head and face. The aim of this study was to analyze parents' subjective assessments of head and facial appearance in children with craniosynostoses before and after surgery. Parents also assessed the interpersonal relationship of their children with peers and adults (after surgery).

METHODS

This study was conducted among parents of 230 children treated in Poland, in two multidisciplinary centers. Detailed statistical analysis was conducted among children who had undergone surgery. Independent variables were age (at survey) of the child (three years and less, four years, and five years and more) and type of craniosynostosis (isolated and syndromic). A chi-square independence test was used. Data was collected using surveys.

RESULTS

In the opinion of most parents, the appearance of their child's head and face after surgery did not differ or differed only slightly from that of their peers. The results of subjective assessment of appearance of children's face and head after reconstructive treatment remains comparable in three subgroups of patients according to the age. It seems that specific head shape according to the type of craniosynostosis does not have an impact on relations with peers and adults.

CONCLUSION

Surgical treatment of children with craniosynostoses improves the appearance of their head and face. This improvement seems not to depend on the type of isolated craniosynostosis, and is constant over time.

Staged Raising of a Coronal Flap for Fronto-Orbital Advancement and Remodeling in Saethre-Chotzen Syndrome Complicated by Sinus Pericranii

This article reports the surgical management of a 3-month-old girl with Saethre-Chotzen syndrome, who presented with bicoronal synostosis and a large midline sinus pericranii with abnormal cerebral venous drainage via scalp veins. Raised intracranial pressure was demonstrated on monitoring, indicating the need for calvarial expansion necessitating a coronal access incision. A 2-staged delayed raising of the coronal flap was performed to reduce the potential risk of cerebral venous infarction. Monitoring for clinical sequelae and a computerised tomography venogram followed each of these procedures, demonstrating successful redirection of the venous drainage of the brain posteriorly. Finally, a successful fronto-orbital advancement and remodeling procedure was performed with no complications.

Proof of Concept Study for the Design, Manufacturing, and Testing of a Patient-Specific Shape Memory Device for Treatment of Unicoronal Craniosynostosis

Treatment of unicoronal craniosynostosis is a surgically challenging problem, due to the involvement of coronal suture and cranial base, with complex asymmetries of the calvarium and orbit. Several techniques for correction have been described, including surgical bony remodeling, early strip craniotomy with orthotic helmet remodeling and distraction. Current distraction devices provide unidirectional forces and have had very limited success. Nitinol is a shape memory alloy that can be programmed to the shape of a patient-specific anatomy by means of thermal treatment.In this work, a methodology to produce a nitinol patient-specific distractor is presented: computer tomography images of a 16-month-old patient with unicoronal craniosynostosis were processed to create a 3-dimensional model of his skull and define the ideal shape postsurgery. A mesh was produced from a nitinol sheet, formed to the ideal skull shape and heat treated to be malleable at room temperature. The mesh was afterward deformed to be attached to a rapid prototyped plastic skull, replica of the patient initial anatomy. The mesh/skull construct was placed in hot water to activate the mesh shape memory property: the deformed plastic skull was computed tomography scanned for comparison of its shape with the initial anatomy and with the desired shape, showing that the nitinol mesh had been able to distract the plastic skull to a shape close to the desired one.The shape-memory properties of nitinol allow for the design and production of patient-specific devices able to deliver complex, preprogrammable shape changes.

Complications following intracranial pressure monitoring in children: a 6-year single-center experience

OBJECTIVE Intracranial pressure (ICP) monitoring is an important tool in the neurosurgeon's armamentarium and is used for a wide range of indications. There are many different ICP monitors available, of which fiber-optic intraparenchymal devices are very popular. Here, the authors document their experience performing ICP monitoring from 2005 to 2015 and specifically complication rates following insertion of the Microsensor ICP monitor. METHODS A retrospective case series review of all patients who underwent ICP monitoring over a 10-year period from 2005 to 2015 was performed. RESULTS There were 385 separate operations with an overall complication rate of 8.3% (32 of 385 cases). Hardware failure occurred in 4.2% of cases, the CSF leakage rate was 3.6%, the postoperative hemorrhage rate was 0.5%, and there was 1 case of infection (0.3% of cases). Only patients with hardware problems required further surgery as a result of their complications, and no patient had any permanent morbidity or mortality from the procedure. Younger patients (p = 0.001) and patients with pathologically high ICP (13% of patients with high ICP vs 6.5% of patients with normal ICP; p = 0.04) were significantly more likely to have complications. There was no significant difference in the complication rates between general neurosurgical patients and craniofacial patients (7.6% vs 8.8%, respectively; p = 0.67). CONCLUSIONS Intraparenchymal ICP monitoring is a safe procedure associated with low complications and morbidity in the pediatric craniofacial and neurosurgical population and should be offered to appropriate patients to assess ICP with the reassurance of the safety record reported in this study.

Osseous Convexity at the Anterior Fontanelle: A Presentation of Metopic Fusion?

BACKGROUND

Craniosynostosis, or a premature fusion of 1 or more cranial vault sutures, results in characteristic head shape deformities. In previous reports, an osseous prominence at the anterior fontanelle has been suggestive of adjacent suture fusion and local elevation in intracranial pressure (ICP). This prominence has been termed the "volcano" sign, and has been described in the anterior fusion of the sagittal suture and serves as an indication for surgery.

METHODS

Two patients presented for head shape evaluation with mild metopic ridging and anterior fontanellar osseous convexities consistent with the volcano sign. Low-dose computed tomography imaging was performed in both patients due to concern for underlying craniosynostosis with elevated locoregional ICP.

RESULTS

In both patients, imaging was significant for a localized, superior forehead metopic fusion, as well as a bony, convex prominence at the site of the ossified anterior fontanelle. There were no other clinical or radiologic signs or symptoms to suggest elevated ICP. Surgery was not indicated in either patient.

CONCLUSIONS

Here the authors present 2 patients with osseous convexities at the site of the closed anterior fontanelle without signs or symptoms of elevated ICP, or classic signs of metopic synostosis. The authors hypothesize that this pattern may be due to a form of mechanically induced premature fusion of a normal metopic suture that is focused superiorly at the bregma, with minimal resultant restriction of overall skull growth. This is in contrast to metopic synostosis, which primarily has a sutural pathology and leads to characteristic findings of hypotelorism and trigonocephaly.

The value of three-dimensional photogrammetry in isolated sagittal synostosis: Impact of age and surgical technique on intracranial volume and cephalic index─a retrospective cohort study

PURPOSE

The aim of this study was to compare the outcome of intracranial volume (ICV) and cephalic index (CI) between two different techniques for surgical therapy of sagittal synostosis.

MATERIAL AND METHODS

Between 2011 and 2015, all patients scheduled for surgical therapy of sagittal synostosis were consecutively enrolled. All patients younger than 6 months underwent early extended strip craniectomy (ESC group), and patients older than 6 months underwent late modified pi-procedure (MPP group). To measure ICV and CI, data acquisition was performed via three-dimensional photogrammetry, 1 day before (T0) and between 10 and 12 weeks after surgery (T1). Results were compared with an age-matched reference group of healthy children. Perioperative parameters, as duration of surgery and the amount of blood loss of both surgical procedures were analyzed.

RESULTS

A total of 85 patients were enrolled. Of the patients, 48 underwent an extended strip craniotomy with parietal osteotomies and biparietal widening and 37 patients underwent a late modified pi-procedure. There was no significant difference between the ESC group and the MPP group regarding the efficacy of improving CI (p > 0.05). Both techniques were able to normalize CI and to improve head shape. ICV was normal compared to age-matched norm-groups with both techniques, pre- and postoperatively. However, duration of the surgical procedure and calculated blood loss were significantly lower in the ESC group (p < 0.05).

CONCLUSION

ESC and MPP were effective techniques to normalize cephalic index (CI) and improve head shape at their recommended time of surgery. Measurement of ICV and CI with 3D photogrammetry is a valid method to objectively evaluate patients before and after surgery without exposing pediatric patients to ionizing radiation.