Congenital dermoid inclusion cyst over the anterior fontanel in Chinese children.

Congenital dermoid inclusion cyst (CDIC) over the anterior fontanel is a rare and benign tumor. This study reports nine Chinese cases (three females and six males) with CDIC over the anterior fontanel. The clinical manifestations and imaging were analyzed retrospectively. Surgical resection was undertaken in all cases. The diagnosis of CDIC over the anterior fontanel was confirmed by histological examination. The cysts were all noticed soon after birth and enlarged gradually. They were soft, nontender with a sessile base without inflammatory signs and breaking. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed soft tissue mass over the anterior fontanel without intracranial extensions. The histopathological examination displayed stratified squamous epithelium with skin appendages. There were no complications or recurrence after operation during a follow-up for one year. CDIC over the anterior fontanel is a benign tumor. Imaging is recommended preoperatively to aid differential diagnosis. The main management is total excision with good prognosis.

Neuroimaging findings using transfontanellar ultrasound in newborns with microcephaly: a possible association with congenital Zika virus infection.

OBJECTIVE: The objective of this study is to determine the main neuroimaging findings of microcephalic newborns with possible Zika virus (ZIKV) intrauterine infection using transfontanellar cranial ultrasound. METHODS: We performed a retrospective study to describe the main neuroimaging findings in newborns with microcephaly and possible association with congenital ZIKV infection. Microcephaly was defined in the postnatal period using transfontanellar cranial examination which was performed using both two- (2D) and three-dimensional (3D) ultrasound. RESULTS: One hundred and fifty newborns with microcephaly were identified during the study period. The mean ± (standard deviation - SD) of cephalic perimeter was 28.5 ± 4.2 cm (range, 25-38 cm). Transfontanellar neuroimaging patterns detected cerebral calcifications, neuronal migrational abnormalities, dysgenesis of the corpus callosum, and cerebellar atrophy in 34.9%, 31.1%, 26%, and 16.2%, respectively. Hydrocephalus was seen in 28% of overall newborns. A history of maculopapular rash was present in almost half of the mothers (46.1%). CONCLUSION: Neuroimaging patterns by means of transfontanellar ultrasound are accurate and diagnostic investigations of brain pathology in newborns affected by microcephaly and possible intrauterine ZIKV infection.

A novel splice site mutation of FGD1 gene in an Aarskog-Scott syndrome patient with a large anterior fontanel.

Aarskog-Scott syndrome (ASS) is a rare X-linked recessive genetic disorder caused by FGD1 mutations. FGD1 regulates the actin cytoskeleton and regulates cell growth and differentiation by activating the c-Jun N-terminal kinase signaling cascade. ASS is characterized by craniofacial dysmorphism, short stature, interdigital webbing and shawl scrotum. However, there is a wide phenotypic heterogeneity because of the additional clinical features. ASS and some syndromes including the autosomal dominant inherited form of Robinow syndrome, Noonan syndrome, pseudohypoparathyroidism, Silver-Russel and SHORT syndrome have some overlapping phenotypic features. Herein, we report a patient with ASS and a large anterior fontanel who was initially diagnosed as Robinow syndrome. He was found to have a novel c.1340+2 T>A splice site mutation on the FGD1 gene.

Posterior fossa abnormalities in high-risk term infants: comparison of ultrasound and MRI.

OBJECTIVES: We aimed to assess the characteristics of posterior fossa (PF) abnormalities in a cohort of high-risk term neonates, as well as the diagnostic performance of cranial ultrasound (CUS) with additional mastoid fontanelle (MF) views for the detection of these abnormalities, with magnetic resonance imaging (MRI) being the reference standard. METHODS: In this retrospective study, 113 term neonates with CUS and subsequent MRI were included. Sensitivity, specificity, and predictive values of routine CUS and CUS with MF views were calculated. RESULTS: Posterior fossa abnormalities were diagnosed on CUS in 46 of 113 infants. MRI confirmed these findings in 43 and showed additional abnormalities in 32 infants. The sensitivity and specificity of anterior fontanelle views for major PF abnormalities as seen on MRI were 16% and 99%. Adding MF views increased the sensitivity of US to 82%. The sensitivity and specificity of MF views for the detection of any (major or minor) PF abnormality were 57% and 95%. Especially acute hypoxic-ischemic injury and small subdural and punctate cerebellar haemorrhage remained undetected by CUS. CONCLUSIONS: PF abnormalities are frequent in high-risk term infants. MF-CUS enables early diagnosis of major PF abnormalities. We therefore advocate to perform MF-CUS in high-risk term neonates. KEY POINTS: • Posterior fossa abnormalities are a frequent finding in high-risk term infants. • Adding mastoid fontanelle views improves ultrasound detection of clinically relevant abnormalities. • Hypoxic-ischemic injury and small posterior fossa haemorrhages are better detected with MRI. • Cranial ultrasound examination should include mastoid fontanelle views in high-risk term neonates.

Primary Ewing's sarcoma of the anterior fontanelle in a neonate.

Primary cranial Ewing`s sarcoma is extremely rare. We present a case of primary Ewing's sarcoma of the skull in a neonate that involved the anterior fontanelle and was very aggressive in nature. Even with radical surgery, the patient had early recurrence within 2 months of surgery and ultimately died. Detailed radiological and pathological findings are described.

Dynamic cervicomedullary cord compression and alterations in cerebrospinal fluid dynamics in children with achondroplasia: review of an 11-year surgical case series.

OBJECT: Achondroplasia may be associated with compression at the cervicomedullary junction. Determining which patients are at greatest risk for neurological complications of cervicomedullary compression can be difficult. In the current study the authors reviewed their records to determine the incidence and clinical significance of dynamic cervicomedullary stenosis and obstruction of CSF flow along with surgical outcomes following posterior fossa decompression. METHODS: The authors reviewed 34 consecutive cases involving symptomatic children with achondroplasia undergoing cervicomedullary decompression performed by a single surgeon over 11 years. Of these patients, 29 had undergone preoperative dynamic MRI of the cervicomedullary junction with cine (cinema) CSF flow studies; 13 of these patients underwent postoperative dynamic MRI studies. Clinical outcomes included changes in polysomnography, head circumference percentile, and fontanel characteristics. Radiographic outcomes included changes in dynamic spinal cord diameter, improvement in CSF flow at the foramen magnum, and change in the Evans ratio. RESULTS: Patients were predominantly female, with a mean age at presentation of 6.6 years and mean follow-up of 3.7 years (range 1-10 years). All patients had moderate to excellent improvement in postoperative polysomnography, slight decrease in average head circumference percentile (from 46.9th percentile to 45.7th percentile), and no subjective worsening of fontanel characteristics. The Evans ratio decreased by 2%, spinal cord diameter increased an average of 3.1 mm, 5.2 mm, and 0.2 mm in the neutral, flexed, and extended positions, respectively, and CSF flow improved qualitatively in all 3 positions. There were no postoperative infections, CSF leaks, or other major complications. None of the patients undergoing initial foramen magnum decompression performed at our medical center required reoperation. CONCLUSIONS: Patients with achondroplasia and symptomatic cervicomedullary compression have increased risk of dynamic stenosis at the foramen magnum evident upon dynamic cine MRI. Operative decompression may be offered with low risk of complications or need for reoperation.

Runx2 is required for early stages of endochondral bone formation but delays final stages of bone repair in Axin2-deficient mice.

Runx2 and Axin2 regulate skeletal development. We recently determined that Axin2 and Runx2 molecularly interact in differentiating osteoblasts to regulate intramembranous bone formation, but the relationship between these factors in endochondral bone formation was unresolved. To address this, we examined the effects of Axin2 deficiency on the cleidocranial dysplasia (CCD) phenotype of Runx2(+/-) mice, focusing on skeletal defects attributed to improper endochondral bone formation. Axin2 deficiency unexpectedly exacerbated calvarial components of the CCD phenotype in the Runx2(+/-) mice; the endocranial layer of the frontal suture, which develops by endochondral bone formation, failed to mineralize in Axin2(-/-):Runx2(+/-) mice, resulting in a cartilaginous, fibrotic and larger fontanel than observed in Runx2(+/-) mice. Transcripts associated with cartilage development (e.g., Acan, miR140) were expressed at higher levels, whereas blood vessel morphogenesis transcripts (e.g., Slit2) were suppressed in Axin2(-/-):Runx2(+/-) calvaria. Cartilage maturation was impaired, as primary chondrocytes from double mutant mice demonstrated delayed differentiation and produced less calcified matrix in vitro. The genetic dominance of Runx2 was also reflected during endochondral fracture repair, as both Runx2(+/-) and double mutant Axin2(-/-):Runx2(+/-) mice had enlarged fracture calluses at early stages of healing. However, by the end stages of fracture healing, double mutant animals diverged from the Runx2(+/-) mice, showing smaller calluses and increased torsional strength indicative of more rapid end stage bone formation as seen in the Axin2(-/-) mice. Taken together, our data demonstrate a dominant role for Runx2 in chondrocyte maturation, but implicate Axin2 as an important modulator of the terminal stages of endochondral bone formation.

Anatomoradiological identification of intrasutural bones for importance of cranial fracture.

AIM: Intrasutural bones are often found within sutures and fontanelles of the skull. It is important that the anatomy of these bones in the field of non-accidental injury with respect to medicolegal complications. Skull fracture lines are critical in their differential diagnosis, and the features of bone formations, their appearance and position give us a more definitive diagnosis. MATERIAL AND METHODS: Intrasutural bone location, its number and symmetry were investigated in totally 300 adult skulls. RESULTS: 27 intrasutural bones were identified as interparietal (2%), preinterparietal (3%) and sutural bones (4%) were in the lambdoid sutures. It was detected that the interparietal and preparietal bones were single, and the sutural ones were in a multiple number. The sutural bones were superposed in significant structures such as sagittal sinus and sinus sigmoideus. CONCLUSION: The ones that should be paid attention to in the differential diagnosis of the skull fracture lines are preinterparietal and interparietal bones in larger sizes. These findings prompted us to report these cases as their presence can lead to confusion in diagnosis in cases of skull fractures.

Variability of resistive indices in the anterior cerebral artery during fontanel compression in preterm and term neonates measured by transcranial duplex sonography.

OBJECTIVE: To determine the normal range of resistive index (RI) variability in clinically/neurologically unremarkable preterm and term infants and to compare the hemodynamic response to transient elevation of intracranial pressure. STUDY DESIGN: We measured RIs at baseline and following brief fontanel compression, assessing for differences in mean baseline and compression values and percent change. RESULT: One hundred and twenty-nine subjects were included in the study. Mean baseline RI and normal range were 0.7 in preterm (0.54 to 0.86) and 0.66 in term infants (0.52 to 0.8; P=0.001). Mean RI during compression was 0.71 in preterm and 0.68 in term infants (P=0.015). Mean percent change between baseline and compression was 5.86% in preterm and 7.45% in term infants (P=0.092). CONCLUSION: No difference in the hemodynamic response to transient elevation of intracranial pressure between different gestational groups, suggesting no significant differences in autoregulatory response.

Cranial computed tomography utilization for suspected ventriculoperitoneal shunt malfunction in a pediatric emergency department.

BACKGROUND: Computed tomography (CT) scan, the largest medical source of ionizing radiation in the United States, is used to test for failure of ventricular peritoneal shunts. STUDY OBJECTIVES: To quantify the exposure to cranial CT scans in pediatric patients presenting with symptoms of shunt malfunction, and to measure the association of signs and symptoms with clinical shunt malfunction and the need for neurosurgical intervention within 30 days of presentation. METHOD: This was a quality improvement study evaluating a pathway used by providers in a tertiary care pediatric emergency department with 85,000 patient visits per year, by retrospective chart review of 223 patient visits for suspected shunt malfunction. We determined the median CT scan per patient per year and the association of signs and symptoms on the pathway with radiological signs of shunt failure and neurosurgical intervention within 30 days of scan. RESULTS: The median exposure was 2.6 (interquartile range 1.44-4.63) scans per patient per year. Among 11 signs and symptoms, none was associated with radiologic shunt failure. Neurosurgical intervention within 30 days was positively associated with bulging fontanelle (adjusted odds ratio [AOR] 11.78; 95% confidence interval [CI] 1.67-83.0) and behavioral change (AOR 3.01; 95% CI 1.14-7.93), and negatively associated with seizure (AOR 0.13; 95% CI 0.02-0.79) and fever (AOR 0.15; 95% CI 0.04-0.55). CONCLUSIONS: Patients with ventricular peritoneal shunts underwent many cranial CT scans each year. None of the signs or symptoms included on the clinical pathway was predictive of changes on CT scan.

Benign extracerebral fluid collection in infancy as a risk factor for the development of de novo intracranial arachnoid cysts.

OBJECT: Intracranial arachnoid cysts are a relatively common benign intracranial pathology, accounting for as many as 0.75%-1% of nontraumatic CNS lesions. Although it has already been demonstrated that rupture of arachnoid cysts may lead to subdural hematomas/hygromas, no study to date has investigated benign extracerebral collection in infancy as a possible predisposing factor for further development of arachnoid cysts. METHODS: The authors performed a retrospective imaging and chart review of macrocephalic infants 12 months old or younger who were referred to neurosurgical care at OSF St. Francis Medical Center from 2003 to 2010, and who were diagnosed with benign extracerebral fluid collection in infancy on thin-slice (1-mm) head CT scans. Special attention was given to the investigation of risk factors for further development of de novo arachnoid cysts. Several epidemiological factors in the infants and mothers were analyzed, including gestational age at delivery, mode of delivery, mother's age at delivery, delivery complications, birth weight, age of macrocephaly development, degree of macrocephaly, family history of macrocephaly, prenatal and postnatal history of infection, fontanel status, presence of papilledema, previous history of head trauma, and smoking status. Imaging characteristics of the initial scans, such as location of subdural collection (frontal vs frontoparietal and frontotemporal) and presence of ventriculomegaly, were also evaluated. For those patients in whom arachnoid cysts were identified on subsequent CT scans, the size and location of the cysts were also analyzed. RESULTS: The authors identified 44 children with benign extracerebral fluid collection in infancy. From this group, over a mean follow-up of 13 months (range 6-13 months), 18 children developed intracranial arachnoid cysts (a 40.9% incidence of de novo development of arachnoid cysts), with 27.8% presenting with bilateral cysts. In the multiple logistic regression analysis, infants who presented with an extracerebral collection restricted to the bilateral frontal region were more likely to develop intracranial arachnoid cysts (p = 0.035) than those with collections involving the frontotemporal and frontoparietal regions (odds ratio [OR] = 5.73). Additionally, children with benign extracerebral fluid collections and plagiocephaly were more likely to develop intracranial arachnoid cysts (p = 0.043) than those without plagiocephaly (OR = 4.96). CONCLUSIONS: This is the first report in the neurosurgical literature demonstrating that benign extracerebral fluid collections in infancy may constitute a significant risk factor for development of de novo arachnoid cysts. These findings support a 2-hit hypothesis for the development of arachnoid cysts, in which the combination of an embryological defect in arachnoid development followed by a second event leading to impairment of CSF fluid absorption in early childhood could lead to abnormal CSF dynamics and the consequent expansion of fluid collections in the intraarachnoid spaces.

Fever and bulging fontanelle mimicking meningitis in an infant diagnosed with benign intracranial hypertension.

A previously healthy 7-month-old male presented to the emergency department with fever and a bulging anterior fontanelle. A computed tomographic scan of the head suggested mild communicating hydrocephalus. Lumbar puncture was performed, which revealed a normal cerebrospinal fluid (CSF) cell count and glucose concentration, but a markedly elevated opening pressure. DNA polymerase chain reaction for herpes simplex virus performed on CSF was negative; CSF bacterial cultures were without growth. DNA polymerase chain reaction for human herpes virus 6 was strongly positive in serum. Fever and bulging fontanelle resolved within 24 hours. A presumptive diagnosis of transient intracranial hypertension of infancy was made, a form of benign idiopathic intracranial hypertension that mimics the presentation of serious intracranial pathology.

The assessment of bulging fontanel and splitting of sutures in premature infants: an interrater reliability study by the Hydrocephalus Clinical Research Network.

OBJECT: Previous studies from the Hydrocephalus Clinical Research Network (HCRN) have shown a great degree of variation in surgical decision making for infants with posthemorrhagic hydrocephalus, such as when to temporize, when to shunt, or when to convert. Since much of this clinical decision making is dictated by clinical signs of increased intracranial pressure (including bulging fontanel and splitting of sutures), the authors investigated whether there was variability in how these signs were being assessed by neurosurgeons. They wanted to answer the following question: is there acceptable interrater reliability in the neurosurgical assessment of bulging fontanel and split sutures? METHODS: Explicit written definitions of "bulging fontanel" and "split sutures" were agreed upon with consensus across the HCRN. At 5 HCRN centers, pairs of neurosurgeons independently assessed premature infants in the first 3 months of life for the presence of a split suture and/or bulging fontanel, according to the a priori definitions. Interrater reliability was then calculated between pairs of observers using the Cohen simple kappa coefficient. Institutional board review approval was obtained at each center and at the University of Utah Data Coordinating Center. RESULTS: A total of 38 infants were assessed by 13 different raters (10 faculty, 2 fellows, and 1 resident). The kappa for bulging fontanel was 0.65 (95% CI 0.41-0.90), and the kappa for split sutures was 0.84 (95% CI 0.66-1.0). No complications from the study were encountered. CONCLUSIONS: The authors have found a high degree of interrater reliability among neurosurgeons in their assessment of bulging fontanel and split sutures. While decision making may vary, the clinical assessment of this cohort appears to be consistent among these physicians, which is crucial for prospective studies moving forward.

Congenital dermoid cyst at the anterior fontanelle: neuroimaging before and after fontanelle closure.

We report on a 2-month-old boy with a dermoid cyst arising at the anterior fontanelle, with observation during both the open and closed stages of the fontanelle. The etiology of this benign, curable tumor is discussed.