Maternal and childhood medical history and the risk of childhood brain tumours: a case-control study in Ontario, Canada.

BACKGROUND: Studies to date have yielded inconclusive results as to whether maternal medical history during pregnancy, and a child's early-life medical history contribute to the development of childhood brain tumours (CBTs). This study examined associations between maternal and childhood medical history and the risk of CBTs. METHODS: The Childhood Brain Tumour Epidemiology Study of Ontario (CBREO) examined children 0-15 years of age with newly diagnosed CBTs from 1997 to 2003. Multivariable logistic regression analysis determined associations for prenatal medications and childhood medical history, adjusted for child's demographics, and maternal education. Analyses were stratified by histology. A latency period analysis was conducted using 12- and 24-month lead times. RESULTS: Maternal intake of immunosuppressants during the prenatal period was significantly associated with glial tumours (OR 2.73, 95% CI 1.17-6.39). Childhood intake of anti-epileptics was significantly associated with CBTs overall, after accounting for 12-month (OR 8.51, 95% CI 3.35-21.63) and 24-month (OR 6.04, 95% CI 2.06-17.70) lead time before diagnosis. No associations for other medications were found. CONCLUSIONS: This study underscores the need to examine potential carcinogenic effects of the medication classes highlighted and of the indication of medication use. Despite possible reverse causality, increased CBT surveillance for children with epilepsy might be warranted.

Childhood head trauma and the risk of childhood brain tumours: A case-control study in Ontario, Canada.

Head trauma in early childhood has been hypothesized as a potential risk factor for childhood brain tumours (CBTs). However, head trauma has not been extensively studied in the context of CBTs and existing studies have yielded conflicting results. A population-based and hospital-based case-control study of children 0 to 15 years with newly diagnosed CBTs from 1997 to 2003 recruited across Ontario through paediatric oncology centres was conducted. Controls were frequency-matched with cases by age, sex and geographical region. The association was assessed based on multivariable logistic regressions, accounting for child's age, sex, ethnicity, highest level of maternal education and maternal pack-years of smoking during the pregnancy. Analyses were conducted separately based on age of first head trauma, sex and histology. A latency period analysis was conducted. Overall, based on 280 cases and 919 controls, CBTs were not significantly associated with previous history of head trauma (OR 1.34, 95% CI 0.96, 1.86), head trauma severity, number of head injuries, or head or neck X-rays or computed tomography (CT) examinations. Results were consistent across sexes and histological subtypes. However, head trauma within the first year of life was significantly associated with CBTs (OR 2.00, 95% CI 1.01, 3.98), but the association diminished when adjusted for X-ray or CT occurring during the same time period (OR 1.62, 95% CI 0.75, 3.49), albeit limited sample size. Overall, no association was observed between head trauma and CBTs among all children, while head trauma occurring within first year of life may warrant further investigation in future research.

Effects of systemic corticosteroid treatment on pseudotumoral hemicerebellitis: a case report and literature review.

PURPOSE: Pseudotumoral hemicerebellitis is an acute, unilateral inflammation of the cerebellum that typically affects the pediatric population. The purpose of this paper is to review cases of pseudotumoral hemicerebellitis in the literature and evaluate if treatment with systemic corticosteroids reduces length of time to symptomatic recovery. METHODS: We present a case report of a 12-year-old male with pseudotumoral hemicerebellitis and unilateral cerebellar dysfunction. Additionally, we review the thirty-five reported cases of pseudotumoral hemicerebellitis with respect to length of time to symptomatic recovery with or without systemic corticosteroid treatment. RESULTS: Thirty cases reported length of time to symptomatic recovery. Including our case, the mean time to recovery for those treated with systemic corticosteroids (n = 20) was 48.05 days (SE = 16.3). The mean time to recovery for those treated without (n = 10) was 86.7 days (SE = 29.3). CONCLUSIONS: Treatment with systemic corticosteroids was associated with a faster time to symptomatic recovery compared to without. Regardless of etiology, reducing inflammation and mass effect involved in pseudotumoral hemicerebellitis may be integral to a more rapid return to neurological baseline.

Congenital Calvarial Hemangioma.

OBJECTIVES: The authors describe a case of congenital calvarial hemangioma successfully managed using propranolol therapy. Presenting symptoms, radiological and pathological features, differential diagnosis, and management of this rare congenital mass are described. CASE PRESENTATION: A 2-year-old boy presented with a 1-year history of a growing right parietal skull mass. No obvious etiology was apparent. No focal neurological deficits or associated craniofacial anomalies were identified. Plain film imaging demonstrated focal thickening of the right parietal bone with internal trabeculations in a sunburst appearance. Computed tomography (CT) scan showed bone thickening with coarsening of the bony trabeculae, minor irregularity of the outer table, unaffected inner table, and no evidence of aggressive features. A diagnostic biopsy of the lesion was performed in the operating room. Microscopic examination was consistent with hemangioma. Based on histological and radiological features of the lesion, it was identified as a cavernous hemangioma. Medical treatment utilizing propranolol was initiated for over 3 years with interval reduction in the lesion size. MRI head following treatment with propranolol demonstrated reduction of the mass compared to preoperative imaging. CONCLUSIONS: Although a rare entity, it is important to consider congenital calvarial hemangioma in the differential diagnosis of slow growing skull lesions due to the possibility of complications as a result of the hemangioma's intracranial extension, and the potential for treatment. En bloc resection has classically been described as a treatment for such lesions, although our case demonstrates that medical treatment with propranolol therapy may be appropriate in certain situations.

Infected cephalohematomas and underlying osteomyelitis: a case-based review.

BACKGROUND: Cephalohematomas are relatively common sub-periosteal collections of blood that tend to resolve spontaneously without treatment. Rarely, they become infected and can be associated with underlying osteomyelitis, meningitis, or sepsis. Common pathogens include Escherichia coli and Staphylococcus species. ILLUSTRATIVE CASE: This report describes the first case of a neonate developing an infected right parietal cephalohematoma and underlying osteomyelitis caused by Morganella morganii, which was cultured in blood and cephalohematoma aspirate. This infant male, whose risk factors included vacuum extraction during delivery and suspected post-natal pneumonia, responded well to a 6-week course of intravenous meropenem with complete resolution of both lesions. CONCLUSION: When an infected cephalohematoma is suspected, aspiration of hematoma fluid should be performed for both diagnostic and therapeutic purposes. Infectious symptoms should warrant prompt investigation and treatment, which may include drainage, debridement, and antibiotics. This report demonstrates that the combination of an infected cephalohematoma and underlying osteomyelitis might not be as uncommon as previously believed.

Pediatric thalamic tumors in the MRI era: a Canadian perspective.

BACKGROUND: Thalamic gliomas are rare. The natural history is unpredictable, and the optimal management of these tumors in children is poorly defined. The aim was to identify outcomes, prognostic factors, and response to various modalities of treatment in a relatively large population of pediatric thalamic tumors from many centers within a fairly homogeneous health care system. METHODS: We performed a Canadian multicenter retrospective review of pediatric thalamic tumors presenting during the MRI era (1989-2012). Radiology and pathology were reviewed by central independent reviewers. Paraffin shavings for RNA extraction were taken and tested for fusion events involving KIAA1549:BRAF. Tumors were classified as unilateral or bithalamic based on their origin on imaging. Univariate and multivariate analyses on factors influencing survival were performed. RESULTS: Seventy-two thalamic tumors were identified from 11 institutions. Females represented 53% of the study population, and the mean age at presentation was 8.9 years. Sixty-two tumors were unilateral and 10 bithalamic. Unilateral tumors had a greater propensity to grow inferiorly towards the brainstem. These tumors were predominantly low grade in comparison to bithalamic tumors which were high-grade astrocytomas. The 5-year overall survival was 61 ± 13% for unithalamic tumors compared to 37 ± 32% for bithalamic tumors (p = 0.097). Multivariate analysis indicated tumor grade as the only significant prognostic factor for unithalamic tumors. Six unilateral tumors, all low grade, were BRAF fusion positive. CONCLUSION: Unilateral and bilateral thalamic tumors behave differently. Surgical resection is an appropriate treatment option in unilateral tumors, most of which are low grade, but outcome is not related to extent of resection (EOR). Bilateral thalamic tumors have a poorer prognosis, but the occasional patient does remarkably well. The efficacy of chemotherapy and radiotherapy has not been clearly demonstrated. Novel therapeutic approaches are required to improve the prognosis for malignant unilateral thalamic tumors and bilateral thalamic tumors.

Seizures in children with dysembryoplastic neuroepithelial tumors of the brain--A review of surgical outcomes across several studies.

PURPOSE: In children and adolescents, dysembryoplastic neuroepithelial tumors (DNETs) of the brain present with seizures almost 100% of the time, potentially creating significant long-term morbidity and disability despite the generally indolent course of the lesion. These tumors also tend to be quite resistant to anti-epileptic drugs which, themselves, can be associated with long-term side effects and resultant disability. Many clinicians advocate early surgical resection of these lesions, but how effective this approach is, and how aggressive tumor removal should be, continues to be debated. METHODS: We performed a systematic review of the relevant literature to identify all reports of DNET resections in pediatric patients published over the past 20 years. In all, over 3000 MEDLINE abstracts were reviewed, ultimately resulting in 13 studies with 185 pediatric DNET patients to review. RESULTS: Surgical resection of the lesion was effective at improving seizures in over 98% of patients and at achieving long-term seizure freedom in 86%. Surgical resection of DNETs also appeared to be quite safe, with no reported perioperative deaths and an overall rate of postoperative complications of 12%; the vast majority of these complications were transient. CONCLUSIONS: Total gross resection of the lesion was the only factor statistically correlated with long-term seizure freedom (r = 0.63, p = 0.03). However, data remain lacking regarding whether this translates into more extensive procedures-like brain mapping and partial lobectomies-being any more effective than simple lesionectomies alone. Further research is clearly needed to address this and other crucial questions.

Familial syndromes associated with intracranial tumours: a review.

BACKGROUND: Most cancers of the central nervous system (CNS) occur sporadically in the absence of any known underlying familial disorder or multi-systemic syndrome. Several syndromes are associated with CNS malignancies, however, and their recognition has significant implications for patient management and prognosis. Patients with syndrome-associated CNS malignancies often have multiple tumours (either confined to one region or distributed throughout the body), with similar or different histology. OBJECTIVE: This review examines syndromes that are strongly associated with CNS cancers: the phakomatosis syndromes, familial syndromes such as Li-Fraumeni and familial polyposis syndromes and dyschondroplasia.

Subarachnoid hemorrhage prevalence and its association with short-term outcome in pediatric severe traumatic brain injury.

BACKGROUND: Subarachnoid hemorrhage (SAH) is an independent prognostic indicator of outcome in adult severe traumatic brain injury (sTBI). There is a paucity of investigations on SAH in pediatric sTBI. The goal of this study was to determine in pediatric sTBI patients SAH prevalence, associated factors, and its relationship to short-term outcome. METHODS: We retrospectively analyzed 171 sTBI patients (pre-sedation GCS ≤8 and head MAIS ≥4) who underwent CT head imaging within the first 24 h of hospital admission. Data were analyzed with both univariate and multivariate techniques. RESULTS: SAH was found in 42 % of sTBI patients (n = 71/171), and it was more frequently associated with skull fractures, cerebral edema, diffuse axonal injury, contusion, and intraventricular hemorrhage (p < 0.05). Patients with SAH had higher Injury Severity Scores (p = 0.032) and a greater frequency of fixed pupil(s) on admission (p = 0.001). There were no significant differences in etiologies between sTBI patients with and without SAH. Worse disposition occurred in sTBI patients with SAH, including increased mortality (p = 0.009), increased episodes of central diabetes insipidus (p = 0.002), greater infection rates (p = 0.002), and fewer ventilator-free days (p = 0.001). In sTBI survivors, SAH was associated with increased lengths of stay (p < 0.001) and a higher level of care required on discharge (p = 0.004). Despite evidence that SAH is linked to poorer outcomes on univariate analyses, multivariate analysis failed to demonstrate an independent association between SAH and mortality (p = 0.969). CONCLUSION: SAH was present in almost half of pediatric sTBI patients, and it was indicative of TBI severity and a higher level of care on discharge. SAH in pediatric patients was not independently associated with increased risk of mortality.

Association of cerebrospinal fluid parameters with treatment and complications among children with cerebrospinal fluid shunt infections: a multicenter study.

OBJECTIVE: Cerebrospinal fluid (CSF) white blood cell (WBC) count, neutrophil percentage, protein concentration, and glucose level are typically measured at diagnosis and serially during the treatment of CSF shunt infections. The objective of this retrospective cohort study was to describe the longitudinal profile of CSF parameters in children with CSF shunt infections and assess their association with treatment and outcome. METHODS: Participants were children treated at 11 tertiary pediatric hospitals in Canada and the United States for CSF shunt infection, from July 1, 2013, through June 30, 2019, with hardware removal, external ventricular drain placement, intravenous antibiotics, and subsequent permanent shunt reinsertion. The relationship between CSF parameters and a complicated course (a composite outcome representing children with at least one of the following: contiguous soft-tissue infection, worsening hydrocephalus, CSF leak, intracranial bleed, brain abscess, venous thrombosis, reinfection after insertion of the new shunt, other complication, ICU admission, or death) was analyzed. RESULTS: A total of 109 children (median age 2.8 years, 44% female) were included in this study. CSF pleocytosis, elevated protein, and hypoglycorrhachia had sensitivities of 69%, 47%, and 38% for the diagnosis of culture-confirmed CSF shunt infection, respectively. The longitudinal profile of the neutrophil percentage followed a monotonic trend, decreasing by 1.5% (95% CI 1.0%-2.0%, p < 0.0001) per day over the course of treatment. The initial WBC count differed significantly between pathogens (p = 0.011), but the proportion of neutrophils, protein concentration, and glucose level did not, and was lowest with Cutibacterium acnes. The duration of antibiotic treatment and the time to shunt reinsertion were longer in patients with a higher initial neutrophil percentage. Fifty-eight patients (53%) had one or more complications during their admission. A neutrophil percentage > 44% (Youden index) in the initial CSF sample was associated with a 1.8-fold (95% CI 1.2- to 2.8-fold) higher relative risk of a complicated course. In a random-intercept, random-slope linear mixed-effects model, the longitudinal neutrophil trajectory differed significantly between patients with and without complications (p = 0.030). CONCLUSIONS: A higher proportion of neutrophils in the CSF at diagnosis was associated with a complicated clinical course. Other CSF parameters were associated with treatment and outcome; however, wide variability in values may limit their clinical utility.

Incidence of major and minor brain injuries in facial fractures.

BACKGROUND: Facial fractures can be associated with brain and cervical spine injuries because impact forces are transmitted through the head and neck. Although major brain injury is commonly recognized in these patients, incidence of minor brain injury is not well-known, despite potential morbidity and mortality. OBJECTIVES: This prospective study aimed to determine the incidence of both major and minor brain injuries in 100 patients presenting to a craniofacial surgery service with facial fractures and to identify characteristics associated with brain injury. METHODS: Data were collected for a 9-month period by a craniofacial surgeon at a level I trauma center. A questionnaire and checklist were designed to capture information about major and minor brain injury in patients with facial fractures. Assessments were completed in the outpatient clinic, emergency department, hospital ward, or intensive care unit during the first patient encounters. RESULTS: The average age of patients was 34 years; 79% were male. Time between injury and assessment ranged from less than a few hours to 4 months. Incidence of brain injury was 67% overall: 29% with major brain injury and 38% with minor injury. Major brain injury was commonly diagnosed early in the emergency department or intensive care unit. Conversely, minor brain injury tended to be diagnosed late in the clinic. Patient age, mechanism of injury, and type of facial fracture predicted brain injuries overall, but mechanism of injury was the sole predictor of minor brain injury. CONCLUSIONS: Facial fractures are often associated with brain injury. A high level of suspicion is warranted for minor traumatic brain injuries.

Cerebrospinal Fluid Shunt Infections: A Multicenter Pediatric Study.

BACKGROUND: Infections complicate 5%-10% of cerebrospinal fluid (CSF) shunts. We aimed to describe the characteristics and contemporary pathogens of shunt infections in children in Canada and the United States. METHODS: Descriptive case series at tertiary care hospitals in Canada (N = 8) and the United States (N = 3) of children up to 18 years of age with CSF shunt infections from July 1, 2013, through June 30, 2019. RESULTS: There were 154 children (43% female, median age 2.7 years, 50% premature) with ≥1 CSF shunt infections. Median time between shunt placement and infection was 54 days (interquartile range, 24 days-2.3 years). Common pathogens were coagulase-negative staphylococci (N = 42; 28%), methicillin-susceptible Staphylococcus aureus (N = 24; 16%), methicillin-resistant S. aureus (N = 9; 5.9%), Pseudomonas aeruginosa (N = 9; 5.9%) and other Gram-negative bacilli (N = 14; 9.0%). Significant differences between pathogens were observed, including timing of infection (P = 0.023) and CSF leukocyte count (P = 0.0019); however, differences were not sufficient to reliably predict the causative organism based on the timing of infection or discriminate P. aeruginosa from other pathogens based on clinical features. Empiric antibiotic regimens, which included vancomycin (71%), cefotaxime or ceftriaxone (29%) and antipseudomonal beta-lactams (33%), were discordant with the pathogen isolated in five cases. There was variability between sites in the distribution of pathogens and choice of empiric antibiotics. Nine children died; 4 (44%) deaths were attributed to shunt infection. CONCLUSIONS: Staphylococci remain the most common cause of CSF shunt infections, although antibiotic resistant Gram-negative bacilli occur and cannot be reliably predicted based on clinical characteristics.

Acute cranial decompression in Meckel-Gruber syndrome and slit-ventricle syndrome with craniocephalic disproportion.

Slit-ventricle syndrome (SVS) is characterized by headaches associated with subnormal ventricular size in patients with shunt-treated hydrocephalus. It commonly occurs in children who have had shunts placed at an early age and is diagnosed when computed tomography scans are carried out to investigate suspected shunt obstruction with an accompanying rise in intracranial pressure (ICP). Overdrainage of cerebrospinal fluid may additionally result in craniocephalic disproportion, potentially by dampening the normal expansile pulsations of the dura against the skull, which leads to craniostenosis. Management is controversial because many strategies have only short-term benefit, and surgical intervention is understandably often seen as a last resort.We present a case of a child with SVS and craniocephalic disproportion who was treated with urgent cranial expansion due to rising ICP. Intraoperative ICP monitoring demonstrates a rapid and sustained drop in ICP, and the patient made an uneventful return to his premorbid condition. We conclude that cranial vault expansion should be considered as an effective treatment for postshunt craniocephalic disproportion in patients with SVS.

Coronal synostosis syndrome (Muenke syndrome): the value of genetic testing versus clinical diagnosis.

BACKGROUND: Muenke syndrome is a fibroblast growth factor receptor 3 (FGFR-3)-associated coronal craniosynostosis syndrome, which was first described in 1997. CASE: We report an infant girl who was born to a 29-year-old primapara at 38 weeks' gestation. When evaluated at 3 days old, physical examination revealed a high forehead with frontal bossing, upturned nose, arched palate, shallow midface structures, and heavily ridged coronal sutures bilaterally. Clinically, the infant seemed to be neurologically normal. Skull radiographs and computed tomography confirmed the presence of bilateral coronal synostosis, with patency of all other sutures. Family history was remarkable, in that the infant's father, paternal grandmother, and a paternal cousin demonstrated subtle craniofacial features, which had not been previously identified. Mutation analysis of FGFR-3 revealed a missense mutation in exon 6, c.749 C>G, with a resultant amino acid change from proline to arginine at codon 250 (P250R), in keeping with Muenke syndrome (Am J Hum Genet 1997;60:555-564). The mutation was subsequently identified in her father, suggesting variable expression in this family, as he had only mild midfacial flattening. At 9 months of age, our patient underwent anterior cranial expansion, correction of orbital hypertelorism, intracranial orbital osteotomies, and advancement of the frontal bandeau. She tolerated the procedure well and has done well postoperatively. CONCLUSIONS: We report the case of an infant with Muenke syndrome, with evidence of variable expressivity within the paternal family. The pertinent literature, in which only 2 prior Canadian cases were identified, is reviewed.

The invasiveness of five medulloblastoma cell lines in collagen gels.

Local recurrence continues to limit survival in medulloblastoma patients, largely related to the persistence of invasive cells at the site of tumour resection and leptomeningeal dissemination. Given the relative dearth of understanding of causative mechanisms behind the invasiveness of medulloblastomas, and a general lack of validated in vitro models with which to study them, our objectives were (1) to obtain quantitative data on the invasiveness of five distinct medulloblastoma cell lines within a 3-dimensional in vitro collagen-based model; and (2) to characterize some of the mechanisms behind invasion, specifically striving to identify proteolytic processes that occur as medulloblastoma cells disrupt and thereby invade the normal tissue surrounding them, and specific inhibitors of these proteolytic enzymes. Five different medulloblastoma cell lines (UW228-1, 2 and 3; Daoy, and Madsen) were implanted onto a 3-dimensional, type I collagen gel assay to assess tumour invasion distance and mean doubling time over 5 days. Proteolytic activity was assessed against collagen types I and IV by measuring the degradation of 3H-collagen I and IV to products soluble in 100% w/v trichloroacetic acid; and general (neutral) proteolytic activity evaluated by measuring the degradation of 3H-albumin. In other experiments, cells were pre-exposed to a variety of protease inhibitors, including inhibitors of metalloproteinases and cysteine, serine and aspartic proteases, and then plated to identify any inhibition of invasion. Inter-group differences in mean invasion distance were assessed by means of Student's t-tests for non-paired subjects, with P < 0.05 set as the threshold for statistical significance. For the inhibitor studies, an inhibition index, called the inhibitory concentration 50, IC-50, was calculated by performing a regression analysis for each inhibitor tested over a range of concentrations, for each cell line. Within hours of implantation, individual cells readily detached from the surface of the cell aggregates and invaded the collagen matrix, to distances of up to 1,200 mum and at rates of up to 300-mum per day; the UW228-1 cell line clearly was less invasive than the other four cell lines. Proteolytic activity was identified against collagen type I, but not against collagen type IV or albumin; but there was no apparent correlation between invasion distance and either cell doubling time or the amount of collagen type I proteolytic activity. Both metalloproteinase inhibitors suppressed tumour invasion, as did one of two cysteine protease inhibitors; but there was no tumour suppression with either serine or aspartic protease inhibition. MMP-1 and 2, and TIMP-1 and 2 all were detectable by Western blot analysis. Medulloblastoma cell invasiveness within the 3-dimensional model used here appears to depend upon a combination of metalloproteinase and cysteine protease activity, a finding that may suggest areas for potential future clinical investigation and therapy.

Osmotic myelinolysis with malignant cerebellar edema occurring after DDAVP-induced hyponatremia in a child.

Central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) are dire neurological disorders, characterized by severe damage to the myelin sheath of neurons, which typically result from rapid correction or overcorrection of systemic hyponatremia. For many years, both conditions have been considered universally fatal, though survivors have been reported more recently. Pediatric cases are rare. We present a 13-year-old boy with panhypopituitarism secondary to repair of a nasofrontal encephalocele in infancy, managed on long-term corticosteroid, deamino arginine vasopressin and thyroid hormone. He presented with severe hyponatremia (116 mEq/l), which during correction rapidly and unexpectedly increased to 176 mEq/l, resulting in profoundly impaired consciousness. Brain imaging revealed multiple bilateral changes in the basal ganglia, thalamus, pons and cerebral white matter, consistent with both CPM and EPM. Malignant cerebellar edema necessitated emergent suboccipital craniectomy, with subsequent improvement in level of consciousness and imaging postoperatively. However, he succumbed to acute cardiorespiratory arrest 8 weeks later. Nine similar cases from the literature are reviewed.

Chiari type 1 malformation in an infant with type 2 Pfeiffer syndrome: further evidence of acquired pathogenesis.

There seems to be an association between type 1 Chiari malformation (CM) and some congenital craniosynostosis syndromes. Type 2 Pfeiffer syndrome is a condition associated with premature fusion of multiple cranial sutures, cloverleaf skull (kleeblatschädel deformity), prominent ptosis, thumb and first toe abnormalities, variable syndactyly, and mutated genes for type 1 or 2 fibroblast growth factor receptor. These children generally do poorly because of significant often severe neurologic and cognitive defects, and many die very young. Roughly half of all patients with Pfeiffer syndrome, and virtually all with type 2 disease, also have type 1 CM. Chiari malformation may not be congenital but acquired as a consequence of the skull deformities and other associated intracranial factors in patients with craniosynostosis. We report a term male infant with type 2 Pfeiffer syndrome, who was not noted to have any CM on initial brain imaging done at 2 months but in whom repeated imaging demonstrated clear evidence of CM by 4 months, despite reconstructive craniotomies and unilateral ventriculoperitoneal shunt insertion. Posterior fossa decompression yielded a good result. This patient provides further evidence to support the concept of acquired tonsillar herniation in patients with craniosynostosis syndromes. The etiology seems multifactorial and related to (1) the disproportionately slow growth of the skull relative to the brain, particularly in the posterior fossa, secondary to early fusion of skull sutures, in turn secondary to congenital deficiencies in fibroblast growth factor receptors; (2) impaired venous sinus drainage; (3) hydrocephalus; and (4) resultant elevations in intracranial pressure.

Craniosynostosis involving the squamous temporal sutures: a rare and possibly underreported etiology for cranial vault asymmetry.

Craniosynostosis is a condition in which 1 or more cranial sutures fuse prematurely, often secondary to a fibroblast growth factor receptor (FGFR) mutation, typically involving FGFR2 or FGFR3. This mutation may occur sporadically or in the setting of a genetic syndrome and typically presents within the first few days of life or in early infancy. Most commonly, the sagittal and coronal sutures are involved, although involvement of the lambdoidal and/or metopic sutures is not uncommon. Surgical correction is undertaken both for cosmetic purposes and to relieve raised intracranial pressure, both of which can be severe, depending on the sutures involved. We report on 2 children who presented in their first year of life with synostosis involving: in one instance, a single squamous temporal suture, and in the other, both squamous temporal sutures. The initial presentation and clinical courses of these 2 patients are highly distinct from one another, although both ultimately did quite well after extensive cranial remodeling. To the best of our knowledge, only a handful of patients with squamous synostosis have been reported in the medical literature.