Restricted diffusion of the callosal splenium is highly specific for seizures in neonates.

BACKGROUND: To determine whether restricted diffusion of the callosal splenium is specific for seizure activity in neonates. METHODS: We performed a retrospective chart review of 123 neonates who had a diagnosis of hypoxic ischemic encephalopathy (HIE) who underwent therapeutic cooling and had magnetic resonance imaging (MRI) within the first 10 days of life. The regions examined for injury include the callosal splenium, cortex, deep gray matter, and subcortical white matter. Neurodevelopmental outcomes were secondarily assessed using the Bayley Scales of Infant Development at 12 to 18 months of age and > 18 months of age. APGAR scores and pH, two important markers of hypoxia/ischemia and encephalopathy, were also analyzed in relation to these outcomes. RESULTS: Approximately 41% of the neonates had at least one abnormal region on brain MRI, and 21% had abnormal signal in the splenium. Clinical and/or electrographic seizures were documented in 32%. Changes in the splenium had a sensitivity of 54%, specificity of 94%, and positive predictive value of 81% for seizure presence. The presence of seizures and splenium lesion was associated poor developmental outcomes at 12 to 18 months of age. APGAR scores at 10 minutes, but not lowest pH was associated with splenial changes. CONCLUSIONS: Restricted diffusion of the callosal splenium is specific for recent seizures in neonates with HIE. Seizures and splenial lesion represent risk factors for poor neurodevelopmental outcomes. Child neurologists and neonatologists should consider splenial signal abnormality in their assessment of neonates at risk for seizures and counsel families about likely outcomes accordingly.

Influence of Pediatric Endoscopic Endonasal Skull Base Resections on Midface and Skull Base Development.

OBJECTIVE: The purpose of this study is to use imaging data to determine if endoscopic endonasal surgery (EES) for skull base tumor resection interrupts skull base growth and development, resulting in an atrophic midface skeletal structure, compared to matched normal controls. METHODS: Data were collected by a retrospective chart review done on children aged 16 years and below who underwent endoscopic tumor resection and had pre- and postoperative magnetic resonance imaging with relevant midface anatomy. 121 normal controls were matched to 20 EES patients by age and gender. Three measurements related to midface anatomy were taken from 1 sagittal T1 slice and 1 axial T2 slice of each scan. Statistical analysis was used to compare growth measures between cases and controls. RESULTS: Twenty patients who underwent EES between November 2015 and April 2018 met our inclusion criteria. The mean age of the patients, 11 males and 9 females, was 10 years, and 8 patients (38%) were aged 7 years or younger. Six patients who had a high-flow CSF leak obtained a nasoseptal flap. A student T test and multivariate regression analysis found that EES did not affect midface and skull base growth. Among the variables assessed, age appears to be the only driver of growth. CONCLUSION: There were no identified differences in craniofacial growth in pediatric patients undergoing EES for skull base tumor resection as compared to the control group. EES does not appear to significantly interfere with midface/skull base development and is a good surgical option for pediatric patients.

The role of computed tomography and magnetic resonance imaging for preoperative pediatric cochlear implantation work-up in academic institutions.

OBJECTIVE: The goal of the study is to investigate the association of pertinent preoperative temporal bone computed tomography (CT) and brain magnetic resonance imaging (MRI) results and intraoperative surgical findings and complications of pediatric cochlear implantation reported in academic settings. METHODS: This is a retrospective review of cochlear implant patients who received a pre-operative temporal bone CT and MRI of the brain between 2005 and 2012 at academic pediatric otolaryngology practices within children's hospitals in the United States and France. Scans were reviewed in a double-blind fashion and compared to intraoperative findings. RESULTS: 91 children were analyzed (mean age 5.54 +/- 0.58 years). A small facial recess identified on CT was associated with difficult insertion of electrodes (P = 0.0003). A prominent sigmoid sinus noted on CT was associated of difficult insertion of electrodes (P = 0.01), iatrogenic tegmen dehiscence (P = 0.005), as well as difficult round window access (P = 0.025). No specific CT finding was found to be associated with external auditory canal injury, perilymphatic gusher, or iatrogenic facial nerve injury. MRI brain and internal auditory canal findings were not predictive of surgical outcomes. CONCLUSIONS: Preoperative CT and MRI remain an important planning tool for pediatric cochlear implantation, particularly in academic institutions. The findings of our study demonstrate that a detailed assessment of both preoperative CT and MRI are valuable for teaching and surgical planning.

A Comparison of Intracranial Volume Growth in Normal Children and Patients With Metopic Craniosynostosis.

BACKGROUND: The impact of metopic craniosynostosis on intracranial volume (ICV) and ICV growth is unclear. In addition, the relationship between head circumference (HC) and ICV in these patients is not previously described. METHODS: A retrospective review of 72 patients with metopic craniosynostosis was performed. The ICVs were calculated from manually segmented preoperative computed tomography scans. Magnetic resonance imaging data for 270 healthy children were available. The ICVs were calculated in FreeSurfer.First, a growth curve for metopic patients was generated and a logarithmic best-fit curve was calculated. Second, the impact of metopic craniosynostosis on ICV relative to healthy controls was assessed using multivariate linear regression. Third, the growth curves for metopic patients and healthy children were compared.Pearson's correlation was used to measure the association between HC and ICV. RESULTS: Mean metopic ICV was significantly lower than normal ICV within the first 3 to 6 months (674.9 versus 813.2 cm; P = 0.002), 6 to 9 months (646.6 versus 903.9 cm; P = 0.005), and 9 to 12 months of life (848.0 versus 956.6 cm; P = 0.038). There was no difference in ICV after 12 months of age (P = 0.916).The ICV growth in patients with metopic craniosynostosis is defined by a significantly different growth curve than in normal children (P = 0.005).The ICV and HC were highly correlated across a broad range of ICVs and patient age (r = 0.98, P < 0.001). CONCLUSION: Patients with metopic craniosynostosis have significantly reduced ICVs compared to healthy children, yet greater than normal ICV growth, which allows them to achieve normal volumes by 1 year of age. The HC is a reliable metric for ICV in these patients.

Intraparenchymal extravasation of gadolinium mimicking an enhancing brain tumor.

Gadolinium (Gd)-enhanced magnetic resonance imaging plays an essential role in the detection, characterization, and staging of intracranial neoplasms and vascular abnormalities. Although Gd is helpful in a majority of situations, it can lead to diagnostic misinterpretation in the setting of active vascular extravasation. Scarce reports of intracranial extravasation of Gd are present in the literature. Here, we report the first case of surgically proven spontaneous intraparenchymal extravasation of Gd mimicking an enhancing intra-axial neoplasm in a pediatric patient. Early and accurate recognition of Gd extravasation is critical in obtaining the accurate diagnosis and triaging patients expeditiously into proper avenues of care.

Can Head Circumference Be Used as a Proxy for Intracranial Volume in Patients With Craniosynostosis?

BACKGROUND: Calculation of intracranial volume from neuroimaging can be complex and time consuming. In the adult population, there is evidence suggesting that owing to its strong correlation, head circumference (HC) may be used as a surrogate for intracranial volume (ICV). We were interested in studying the correlation between HC and ICV in patients with craniosynostosis. METHODS: After institutional review board approval, a retrospective review was performed on patients with craniosynostosis. GE Healthcare AdW 4.3 volume assessment software was used to calculate ICV and HC based on preoperative computed tomographic scans. Pearson correlation was used to estimate correlation coefficients between ICV and HC for this patient population, with 0 to 0.3 considered a weak correlation, 0.4 to 0.6 considered a moderate correlation, 0.7 to 1 considered a strong correlation, and P < 0.05 was considered statistically significant. RESULTS: A total of 196 craniosynostosis patients were included in this study. There were 121 male and 75 female patients. Seventy-nine patients had metopic, 45 had coronal, 64 had sagittal, and 8 had lambdoid synostosis. Mean age was 8.2 months. Mean HC and ICV were 42.9 cm and 829 cm, respectively. Overall, there was a strong correlation between HC and ICV (r = 0.81). Patients were further categorized by craniosynostosis type. Very strong correlation was obtained for patients with coronal (0.89), metopic (0.98), and lambdoid craniosynostosis (0.97). Strong correlation was obtained for patients with sagittal synostosis (0.73). When categorized by sex, a stronger correlation was obtained for female patients (0.84) compared with male patients (0.80). Statistical significance was reached for all reported correlations. CONCLUSION: Our preliminary data suggest that a very strong correlation exists between HC and ICV for male and female patients with all types of craniosynostosis, making HC a useful surrogate for ICV in this patient population.

A Study to Evaluate Change in Ventricular Volume Obtained by Cranial Distraction for Craniosynostosis.

BACKGROUND: The aims of the current analysis were to study the change in ventricular volume (VV) obtained with cranial distraction in patients with craniosynostosis and compare it with the change in total intracranial volume (ICV) and brain volume. METHODS: After institutional review board approval, a retrospective review was performed on patients undergoing cranial distraction over a 5-year period. GE Healthcare AdW 4.3 volume assessment software was utilized to calculate preoperative and postdistraction ICV, VV, and whole-brain volume. Data were also collected on patient demographics, age at the time of distraction, time spent in distraction and consolidation, and length of stay. t Tests were used for comparison. RESULTS: Twenty-three patients met our inclusion criteria. Forty-eight percent of patients (n = 11) had right-sided cranial distraction, 30% (n = 7) had bilateral distraction, and 22% of patients (n = 5) had left-sided distraction. At the preoperative stage, mean head circumference was 42.5 ± 4.7 cm, mean ICV was 810.1 ± 27 cm, mean non-VV (NVV) was 796.2 ± 268 cm, and mean VV was 13.9 ± 9 cm. After a mean of 27.4 mm of distraction, occurring over a mean of 26 days and consolidation period of 149 days, a second computed tomography scan was obtained. Mean postdistraction head circumference was 49.1 ± 3.9 cm, mean ICV was 1074.1 ± 203 cm, mean NVV was 1053.5 ± 197 cm, and VV was 20.6 ± 14 cm. Mean % increase in ICV at this stage was 47.4%; mean % NVV increase was 48.5% as opposed to 60.3% increase in VV. CONCLUSIONS: Cranial distraction is known to effectively increase ICV. Our study suggests that the effect of this volumetric increase is much more pronounced on the VV compared with the brain volume. Further studies are underway to investigate whether this short-term marked increase in VV is sustained over a long-term period.

Terson Syndrome Before Induction Chemotherapy for Acute Lymphoblastic Leukemia.

A previously healthy 2-year-old female infant presented with pancytopenia and was diagnosed with acute lymphoblastic leukemia. Before the initiation of treatment, she developed symptoms concerning for increased intracranial pressure. Head imaging revealed left parietal hemorrhage, in addition to a right vitreous hemorrhage, which was confirmed on ophthalmology examination later. Terson syndrome, in which intraocular hemorrhage is associated with intracranial hemorrhage, is more commonly reported in adults, although ocular manifestations of leukemia have been reported at presentation and are typically asymptomatic.

Management of Large-Volume Subperiosteal Abscesses of the Orbit: Medical vs Surgical Outcomes.

Objectives To compare clinical variables and outcomes for children with subperiosteal abscesses of the orbit (SPAO) managed medically vs surgically to identify clinical prognosticators. Study Design Case series with chart review. Setting Tertiary children's academic institution. Subjects and Methods The study included 48 children between the age of 1 month and 14 years, with SPAO from 2003 to 2013. Variables included age, sex, physical examination findings, laboratory results, computed tomography (CT) findings, hospital length of stay, length of antibiotic therapy, and placement of a peripherally inserted central catheter (PICC). Intended methods for comparison were the Student t test for continuous variables and Fisher's exact test for categorical variables, and a forward stepwise multiple logistic regression. Results Thirty-two (67%) children were successfully treated with antibiotic therapy only, and 16 (33%) required surgery. Abscess volume, abscess width, and the presence of gaze restriction were statistically different between the 2 groups. A multivariate analysis found abscess volume as the only predictor for surgical intervention. A subgroup analysis including only patients with an abscess volume of ≥500 mm3 (n = 26) was performed. Eleven patients were treated medically and 15 treated surgically, with the medical group having longer hospital stays ( P = .048), duration of antibiotic therapy ( P = .035), and higher incidence of PICC placement ( P = .005). Conclusions This is the first study to report that abscess volume has clinical implications, as children with SPAO volume ≥500 mm3 treated medically have longer inpatient admissions, antibiotic therapy durations, and PICC placement. When children present with an abscess ≥500 mm3, early surgical intervention should be strongly considered, even in the absence of other surgical criteria, to shorten duration of hospitalization and accelerate clinical improvement.

Effects of tryptophan depletion on the binding of [11C]-DASB to the serotonin transporter in baboons: response to acute serotonin deficiency.

BACKGROUND: The objective of this study was to evaluate the sensitivity of [(11)C]-N,N-dimethyl-2-(2-amino-4-cyanophenylthio)benzylamine (DASB) binding to the brain serotonin transporter (SERT) to changes in endogenous serotonin (5-hydroxytryptamine [5-HT]) levels. A ligand sensitive to endogenous competition (EC) would enable the measurement of fluctuations of intrasynaptic 5-HT. A ligand insensitive to EC can provide a measure of SERT unaffected by levels of 5-HT. Alternatively, serotonin depletion could accelerate internalization of SERT and reduce binding. METHODS: Eighteen (14 baseline and 9 tryptophan-depleted) positron emission tomography (PET) scans were carried out in two baboons (Papio anubis). A metabolite-corrected arterial input function was used to estimate the binding potential (BP = B(max)/K(D)). RESULTS: Depletion of plasma tryptophan by a mean of 65% from the baseline (p = .03) reduces [(11)C]-DASB BP in the six brain regions of interest (ROI). Lower DASB binding correlated with lower plasma tryptophan levels in the ROIs with higher SERT density. CONCLUSIONS: [(11)C]-DASB binding to SERT in vivo rapidly declines in response to acute reduction in serotonin availability, contrary to what is predicted by a simple competition model. This rapid reduction in SERT availability may be due to accelerated transporter internalization.