Radiation exposure in the treatment of pediatric supracondylar humerus fractures.

PURPOSE: To determine the factors that influence radiation exposure during repair of supracondylar humerus fractures. METHODS: Medical records of almost 200 children with supracondylar fractures were retrospectively analyzed for variables correlated with fluoroscopy time and radiation dose as measures of radiation exposure. RESULTS: There was no statistically significant difference in fluoroscopy time (27 vs. 22 s p = 0.345) or direct radiation dose (0.394 vs. 0.318 mSv p = 0.290) between uniplanar and biplanar C-arm use. No statistically significant differences in fluoroscopy time or radiation dose were found for surgical technique, comorbid ipsilateral fractures, preoperative neurovascular compromise, or resident participation. There was a significant 8.3 s increase in fluoroscopy time (p = 0.022) and 0.249 mSv increase in radiation dose (p = 0.020) as the fracture type increased from II to III. An increase in one pin during CRPP resulted in a statistically significant 10.4 s increase in fluoroscopy time and a 0.205 mSv increase in radiation dose. There were significant differences between the physician with the lowest fluoroscopy time and radiation dose compared with the physicians with the two highest values for both fluoroscopy time and radiation dose (p < 0.01). CONCLUSIONS: We found no significant difference in direct radiation exposure or fluoroscopy time when comparing biplanar to uniplanar C-arm use, resident participation, preoperative neurovascular compromise, or for comorbid ipsilateral fractures. Both outcomes increased significantly as fracture type increased from II to III and as the number of pins used during CRPP increased. Both outcomes were significantly different between the surgeons performing CRPP.

Efficacy of tympanostomy tube placement with adjuvant adenoidectomy in children less than 4 years of age.

OBJECTIVE: About 8.6 % of children in the United States undergo tympanostomy tube (TT) placement every year. Of these, 24.1 % require a second set of tubes. Adjuvant adenoidectomy in children over 4 years is thought to improve the efficacy of TT. The goal of this study is to characterize the efficacy of adjuvant adenoidectomy at the time of TT placement in children under 4 years, to further improve middle ear function. METHODS: All patients undergoing TT placement alone or TT placement with adenoidectomy from 2014 to 2016 were reviewed. The primary outcome was need for subsequent tube placement. RESULTS: A total of 409 patients were included in the study (60.6 % male, 39.4 % female). Median age at initial TT placement was 18 months (range 5-48 months); extreme outliers for age were removed from further analysis. Patients were followed for 1-8 years. 250 patients received TT alone while 159 received TT with adenoidectomy. 120 required a second set of tubes. There was a statistically significant benefit to those undergoing adjuvant adenoidectomy with TT placement: 33.6 % of those receiving TT alone required subsequent tubes, whereas only 22.6 % of patients who underwent TT with adjuvant adenoidectomy required reinsertion (X2 = 5.630, p = 0.018). Adjuvant adenoidectomy in patients 0-48 months was associated with decreased likelihood of requiring subsequent tube placement (OR = 0.578, p = 0.018). There was an increased likelihood of experiencing otorrhea in those receiving TT alone compared to the TT with adenoidectomy group (X2 = 4.353, df = 1, p = 0.0369). CONCLUSION: Adjuvant adenoidectomy at the time of initial TT placement may have a role in the management of chronic middle ear disease in patients younger than 4 years. However, further studies and prospective randomized studies are needed to explore if this benefit can also be seen in children without chronic rhinosinusitis or nasal obstruction. The benefit-risk ratio from adenoidectomy and modifications in anesthesia technique in the case of adjuvant adenoidectomy should also be further explored.

Use of an adaptive sensory environment in patients with autism spectrum disorder (ASD) in the perioperative environment: a parallel, randomized controlled trial.

Background: Patients with autism spectrum disorders (ASD) experience higher rates of perioperative anxiety and are likely to receive premedication. Little is known about nonpharmaceutical interventions which may decrease anxiety. This study aims to evaluate the use of an adaptive sensory environment (ASE) to reduce ASD patient anxiety during the perioperative process. Methods: Our feasibility study (ClinicalTrials.govNCT04994613) enrolled 60 patients in two parallel groups randomized to a control (no ASE) or intervention group (ASE). We included all surgical patients aged three to twelve years, with a formal diagnosis of ASD, Asperger's Syndrome, or pervasive developmental disorder not otherwise specified. Preoperative behaviors were recorded by an unblinded nurse utilizing the validated Modified Yale Preoperative Anxiety Scale (mYPAS). The difference in score on the mYPAS was the primary outcome, and an intention-to-treat analysis was employed. A generalized estimating equations model was used to compare mYPAS scores controlling for significant independent variables. Findings: 58 patients were analyzed after 1:1 randomization of 30 patients to each group. Groups were balanced except the median number of intraoperative pain medications was significantly lower in the ASE group (1 vs. 3, p = 0.012). Mean (SD) age for all patients was 7.2 (2.9) years, range 2.6-12.7. 72.4% (42/58) were White and all were Non-Hispanic or Latino. 74% were Male (21/30 ASE and 22/28 Control) and 26% were Female (9/30 ASE and 6/28 Control). No differences were found in mYPAS scores between groups at three time periods (43.5 vs. 42, p = 0.88, 47.8 vs. 48.4, p = 0.76, and 36.4 vs. 43.8, p = 0.15, ASE vs. control group, respectively). The ASE group had a significant within-group decrease in mYPAS scores from nursing intake to transition (p = 0.030). Interpretation: An ASE did not significantly reduce perioperative anxiety. However, the promising results deserve further investigation. Funding: Dayton Children's Hospital Foundation Robert C. Cohn Memorial Research Grant.

Safety and Cost Savings Using Polymeric Clips in Appendectomies in the Pediatric Population: Single-Center Experience.

INTRODUCTION: Although laparoscopic appendectomy is standard management for appendicitis, management of the appendiceal stump remains debated. Even though most surgeons can agree on the safety and effectiveness of various closure methods for the appendiceal stump, such as the surgical stapler (SS) or the Endoloop, the cost of these methods should also be considered. A relatively new alternative method, the polymeric clips (PC), has been gaining acceptance in the surgical community as it has repeatedly proven to be as safe as other methods, while being significantly cheaper. METHODS: For the period of January 2019 to December 2021, we performed a retrospective chart review of a single surgeon's laparoscopic appendectomies in children 18 years or younger for acute, non-complicated appendicitis and grouped the cases by appendiceal stump management (SS or PC). Demographics collected included gender, age, BMI percentile, race, and ASA score. Surgical variables included length of stay, surgical time, and anesthesia time. Outcomes were number of intra- and post-operative complications, reoperations, ER visits within 30 days, and total implant cost. Mann-Whitney U tests were performed to test for differences between SS and PC groups in surgical variables. Chi-square or Fisher's exact tests were performed to test differences in demographics and outcome variables. RESULTS: There were 107 patients identified. The PC group represented 16% (n = 17) of our study population. The PC group was significantly younger than the SS group at 10 years (2.8) vs 12 years (3.5) p = 0.04. No differences were observed in length of stay and anesthesia time between the two groups. However, a significantly longer length of surgery was observed in the PC group at 33.5 min [30.0-43.3] when compared to the SS group at 28.0 min [23.0-36.0] (p = 0.003). No significant differences were seen in post-op complications, post-op ED visits and reoperations within 30 days. The median total implant cost of the PC closure method was significantly lower than the SS method ($35.36 vs. $375.67 p = <0.001). CONCLUSION: There were no significant differences in clinical outcomes. However, the significant difference in the implant cost between the 2 methods could favor the use of PC for selected cases. The increase in length of surgery can be attributed to the learning curve associated with a new device.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Patients With Chiari Malformation: Surgical Interventions.

BACKGROUND: Chiari malformation type I (CIM) diagnoses have increased in recent years. Controversy regarding the best operative management prompted a review of the literature to offer guidance on surgical interventions. OBJECTIVE: To assess the literature to determine (1) whether posterior fossa decompression or posterior fossa decompression with duraplasty is more effective in preoperative symptom resolution; (2) whether there is benefit from cerebellar tonsillar resection/reduction; (3) the role of intraoperative neuromonitoring; (4) in patients with a syrinx, how long should a syrinx be observed for improvement before additional surgery is performed; and 5) what is the optimal duration of follow-up care after preoperative symptom resolution. METHODS: A systematic review was performed using the National Library of Medicine/PubMed and Embase databases for studies on CIM in children and adults. The most appropriate surgical interventions, the use of neuromonitoring, and clinical improvement during follow-up were reviewed for studies published between 1946 and January 23, 2021. RESULTS: A total of 80 studies met inclusion criteria. Posterior fossa decompression with or without duraplasty or cerebellar tonsil reduction all appeared to show some benefit for symptom relief and syrinx reduction. There was insufficient evidence to determine whether duraplasty or cerebellar tonsil reduction was needed for specific patient groups. There was no strong correlation between symptom relief and syringomyelia resolution. Many surgeons follow patients for 6-12 months before considering reoperation for persistent syringomyelia. No benefit or harm was seen with the use of neuromonitoring. CONCLUSION: This evidence-based clinical guidelines for the treatment of CIM provide 1 Class II and 4 Class III recommendations. In patients with CIM with or without syringomyelia, treatment options include bone decompression with or without duraplasty or cerebellar tonsil reduction. Improved syrinx resolution may potentially be seen with dural patch grafting. Symptom resolution and syrinx resolution did not correlate directly. Reoperation for a persistent syrinx was potentially beneficial if the syrinx had not improved 6 to 12 months after the initial operation. The full guidelines can be seen online at https://www.cns.org/guidelines/browse-guidelines-detail/3-surgical-interventions .

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Patients With Chiari Malformation: Diagnosis.

BACKGROUND: Chiari I malformation (CIM) is characterized by descent of the cerebellar tonsils through the foramen magnum, potentially causing symptoms from compression or obstruction of the flow of cerebrospinal fluid. Diagnosis and treatment of CIM is varied, and guidelines produced through systematic review may be helpful for clinicians. OBJECTIVE: To perform a systematic review of the medical literature to answer specific questions on the diagnosis and treatment of CIM. METHODS: PubMed and Embase were queried between 1946 and January 23, 2021, using the search strategies provided in Appendix I of the full guidelines. RESULTS: The literature search yielded 567 abstracts, of which 151 were selected for full-text review, 109 were then rejected for not meeting the inclusion criteria or for being off-topic, and 42 were included in this systematic review. CONCLUSION: Three Grade C recommendations were made based on Level III evidence. The full guidelines can be seen online at https://www.cns.org/guidelines/browse-guidelines-detail/1-imaging .

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Patients With Chiari Malformation: Symptoms.

BACKGROUND: Chiari I malformation (CIM) is characterized by descent of the cerebellar tonsils through the foramen magnum, potentially causing symptoms from compression or obstruction of the flow of cerebrospinal fluid. Diagnosis and treatment of CIM is varied, and guidelines produced through systematic review may be helpful for clinicians. OBJECTIVE: To perform a systematic review of the medical literature to answer specific questions on the diagnosis and treatment of CIM. METHODS: PubMed and Embase were queried between 1946 and January 23, 2021, using the search strategies provided in Appendix I of the full guidelines. RESULTS: The literature search yielded 430 abstracts, of which 79 were selected for full-text review, 44 were then rejected for not meeting the inclusion criteria or for being off-topic, and 35 were included in this systematic review. CONCLUSION: Four Grade C recommendations were made based on Class III evidence, and 1 question had insufficient evidence. The full guidelines can be seen online at https://www.cns.org/guidelines/browse-guidelines-detail/2-symptoms .

Toward rational use of repeat imaging in children with mild traumatic brain injuries and intracranial injuries.

OBJECTIVE: Limited evidence exists on the utility of repeat neuroimaging in children with mild traumatic brain injuries (mTBIs) and intracranial injuries (ICIs). Here, the authors identified factors associated with repeat neuroimaging and predictors of hemorrhage progression and/or neurosurgical intervention. METHODS: The authors performed a multicenter, retrospective cohort study of children at four centers of the Pediatric TBI Research Consortium. All patients were ≤ 18 years and presented within 24 hours of injury with a Glasgow Coma Scale score of 13-15 and evidence of ICI on neuroimaging. The outcomes of interest were 1) whether patients underwent repeat neuroimaging during index admission, and 2) a composite outcome of progression of previously identified hemorrhage ≥ 25% and/or repeat imaging as an indication for subsequent neurosurgical intervention. The authors performed multivariable logistic regression and report odds ratios and 95% confidence intervals. RESULTS: A total of 1324 patients met inclusion criteria; 41.3% of patients underwent repeat imaging. Repeat imaging was associated with clinical change in 4.8% of patients; the remainder of the imaging tests were for routine surveillance (90.9%) or of unclear prompting (4.4%). In 2.6% of patients, repeat imaging findings were reported as an indication for neurosurgical intervention. While many factors were associated with repeat neuroimaging, only epidural hematoma (OR 3.99, 95% CI 2.22-7.15), posttraumatic seizures (OR 2.95, 95% CI 1.22-7.41), and age ≥ 2 years (OR 2.25, 95% CI 1.16-4.36) were significant predictors of hemorrhage progression and/or neurosurgery. Of patients without any of these risk factors, none underwent neurosurgical intervention. CONCLUSIONS: Repeat neuroimaging was commonly used but uncommonly associated with clinical deterioration. Although several factors were associated with repeat neuroimaging, only posttraumatic seizures, age ≥ 2 years, and epidural hematoma were significant predictors of hemorrhage progression and/or neurosurgery. These results provide the foundation for evidence-based repeat neuroimaging practices in children with mTBI and ICI.

Measures of Intracranial Injury Size Do Not Improve Clinical Decision Making for Children With Mild Traumatic Brain Injuries and Intracranial Injuries.

BACKGROUND: When evaluating children with mild traumatic brain injuries (mTBIs) and intracranial injuries (ICIs), neurosurgeons intuitively consider injury size. However, the extent to which such measures (eg, hematoma size) improve risk prediction compared with the kids intracranial injury decision support tool for traumatic brain injury (KIIDS-TBI) model, which only includes the presence/absence of imaging findings, remains unknown. OBJECTIVE: To determine the extent to which measures of injury size improve risk prediction for children with mild traumatic brain injuries and ICIs. METHODS: We included children ≤18 years who presented to 1 of the 5 centers within 24 hours of TBI, had Glasgow Coma Scale scores of 13 to 15, and had ICI on neuroimaging. The data set was split into training (n = 1126) and testing (n = 374) cohorts. We used generalized linear modeling (GLM) and recursive partitioning (RP) to predict the composite of neurosurgery, intubation >24 hours, or death because of TBI. Each model's sensitivity/specificity was compared with the validated KIIDS-TBI model across 3 decision-making risk cutoffs (<1%, <3%, and <5% predicted risk). RESULTS: The GLM and RP models included similar imaging variables (eg, epidural hematoma size) while the GLM model incorporated additional clinical predictors (eg, Glasgow Coma Scale score). The GLM (76%-90%) and RP (79%-87%) models showed similar specificity across all risk cutoffs, but the GLM model had higher sensitivity (89%-96% for GLM; 89% for RP). By comparison, the KIIDS-TBI model had slightly higher sensitivity (93%-100%) but lower specificity (27%-82%). CONCLUSION: Although measures of ICI size have clear intuitive value, the tradeoff between higher specificity and lower sensitivity does not support the addition of such information to the KIIDS-TBI model.

Gigli saw facilitates safe minimal access sagittal suturectomy in infants.

The authors describe the use of the Gigli saw for craniectomy in minimal access surgery to address sagittal craniosynostosis. This modification allows for supine positioning and avoidance of potential brain compression with endoscopic instruments, and provides visually clear, safe, and facile removal of the fused suture and surrounding calvaria. The video can be found here: https://vimeo.com/511568750.

Development and external validation of the KIIDS-TBI tool for managing children with mild traumatic brain injury and intracranial injuries.

BACKGROUND: Clinical decision support (CDS) may improve the postneuroimaging management of children with mild traumatic brain injuries (mTBI) and intracranial injuries. While the CHIIDA score has been proposed for this purpose, a more sensitive risk model may have broader use. Consequently, this study's objectives were to: (1) develop a new risk model with improved sensitivity compared to the CHIIDA model and (2) externally validate the new model and CHIIDA model in a multicenter data set. METHODS: We analyzed children ≤18 years old with mTBI and intracranial injuries included in the PECARN head injury data set (2004-2006). We used binary recursive partitioning to predict the composite outcome of neurosurgical intervention, intubation for > 24 h due to TBI, or death due to TBI. The new model was externally validated in a separate data set that included children treated at any one of six centers from 2006 to 2019. RESULTS: Based on 839 patients from the PECARN data set, a new risk model, the KIIDS-TBI model, was developed that incorporated imaging (e.g., midline shift) and clinical (e.g., Glasgow Coma Scale score) findings. Based on the model-predicted probability of the composite outcome, three cutoffs were evaluated to classify patients as "high risk" for level of care decisions. In the external validation data set consisting of 1,630 patients, the most conservative cutoff (i.e., any predictor present) identified 119 of 119 children with the composite outcome (sensitivity = 100%), but had the lowest specificity (26.3%). The other two decision-making cutoffs had worse sensitivity (94.1%-96.6%) but improved specificity (67.4%-81.3%). The CHIIDA model lacked the most conservative cutoff and otherwise showed the same or slightly worse performance compared to the other two cutoffs. CONCLUSIONS: The KIIDS-TBI model has high sensitivity and moderate specificity for risk stratifying children with mTBI and intracranial injuries. Use of this CDS tool may help improve the safe, resource-efficient management of this important patient population.

The perception of complications in pediatric spine surgery: a comparative survey of surgeons, caregivers and patients.

BACKGROUND/AIMS: The perception of a surgical complication may differ between surgeons and patients. In pediatric spine surgery, the perception of the parent or primary caregiver may also differ. In order to better define these relationships, we performed a pilot study surveying a convenience sample of pediatric spinal surgeons, patients and their parent or primary caregiver. We hope to use this initial pilot study as a starting point for future research into this incompletely defined, yet increasingly relevant topic. METHODS: A survey of case vignettes describing a potential perioperative complication was administered to 14 pediatric spine surgeons at the Texas Children's Hospital Pediatric NeuroSpine Clinic from June 1 to July 31, 2009. The same survey, with modified language, was presented to a group of 13 pediatric patients (age range: 12-18 years). In addition, the surveys were separately presented to 34 primary caregivers of pediatric patients evaluated in a spine surgery clinic. The 61 respondents were asked to evaluate the cases and determine if there was a minor, a major or no complication present. Fisher's exact test was employed to evaluate associations of respondent groups and complication severity. RESULTS: There were no statistically significant differences in the proportion of patients and caregivers rating the presence of complications. In 8 of 13 cases, a majority of surgeons and a majority of patients/caregivers felt a complication was present (all p > 0.06). A greater proportion of surgeons than patients/caregivers felt a complication was present in 2 cases of transient neurological deficit/paraparesis (6 weeks to 6 months; p < 0.04) and 1 case of cosmetically significant pressure sores to the face (p = 0.0002). A greater proportion of patients/caregivers identified a complication in a loss of range of motion after occipitocervical fusion (p < 0.0001) and a loss of motor evoked potentials without a neurological deficit. Amongst those who identified a complication, a greater proportion of surgeons considered the following as a 'major' complication: malpositioned spinal instrumentation with a return to the operating room (p = 0.02); transient new neurological deficit (p < 0.01), and deep wound infection with return to the operating room (p < 0.01). In no scenario did a greater proportion of patients/caregivers consider the complication 'major' compared to surgeons. CONCLUSIONS: In this pilot study, there appear to be differences in how postoperative complications are perceived by surgeons when compared to patients/caregivers. The importance of reconciling such differing opinions through open discussions between surgeons, patients and their families is integral to ensure congruent expectations of planned surgical interventions.

Complications of Gamma Knife surgery: an early report from 2 Canadian centers.

OBJECT: Gamma Knife surgery (GKS) is used to treat benign and malignant brain tumors, arteriovenous malformations, trigeminal neuralgia, and other conditions. Patients experience reduced neurological morbidity from GKS compared with open microneurosurgery, but risks of radiation injury and technical limitations persist. The authors report treatment complications from the early experience of 2 Canadian GKS programs in Toronto and Sherbrooke. METHODS: In Toronto, a prospective administrative database was searched for adverse events and incomplete treatment administrations. In Sherbrooke, data were acquired by chart review. Patients were accrued until August 1, 2007, and a total of 973 patients were included in this report. RESULTS: During the radiosurgical procedure, 19 patients (2%) suffered anxiety or syncopal episodes, and 2 patients suffered acute coronary events. Treatments were incompletely administered in 12 patients (1.2%). Severe pain was a delayed complication: 8 patients suffered unexpected headaches, and 9 patients developed severe facial pain. New motor deficits developed in 11 patients, including edema-induced ataxia in 4 and one case of facial weakness after treatment of a vestibular schwannoma. Four patients required shunt placement for symptomatic hydrocephalus, and 16 patients suffered delayed seizures. CONCLUSIONS: Gamma Knife surgery is a minimally invasive treatment modality for many intracranial diseases. Treatment is not risk free, and some patients will develop complications; these are likely to decrease as institutional experience matures. Expanding availability and indications necessitate discussion of these risks with patients considering treatment.

Corpus callosotomy in children with intractable epilepsy using frameless stereotactic neuronavigation: 12-year experience at the Hospital for Sick Children in Toronto.

OBJECT: Although corpus callosotomy has been used effectively since the late 1930s to treat severe, medically intractable seizure disorders, particularly atonic or drop-attack seizures, controversy remains as to when, how, and how much surgery should be performed. Intraoperative determination of the extent of callosotomy, the need to stage the procedure, and the side of the interhemispheric approach represent technical issues that remain debatable. The authors report the 12-year experience of the senior author as well as surgical outcomes with corpus callosotomy using a frameless stereotactic neuronavigation system (ISG View Wand and BrainLab). METHODS: Thirteen consecutive children at The Hospital for Sick Children underwent single-stage corpus callosotomy for medically intractable seizures. The mean age was 10.3 years. Five children underwent partial callosotomy, and 8 underwent complete callosotomy. The side of operative approach to avoid large parasagittal bridging veins was determined by preoperative study of 3D MR imaging/MR venography reconstructed by the neuronavigation system. The extent of callosotomy was determined using intraoperative feedback from the neuronavigation system and postoperative MR imaging. RESULTS: The extent of callosotomy determined by intraoperative neuronavigation and postoperative MR imaging correlated closely in all cases. There were no operative deaths. There was no significant postoperative morbidity related to venous infarction. Four of 5 patients in the partial callosotomy cohort and 7 of 8 patients in the complete callosotomy cohort showed significant improvement in seizure control. CONCLUSIONS: The use of frameless stereotactic neuronavigation is a safe, effective, and important surgical adjunct in the planning and execution of successful corpus callosotomy in children with intractable epilepsy.

Accurate placement of cerebrospinal fluid shunt ventricular catheters with real-time ultrasound guidance in older children without patent fontanelles.

The authors present a technique in which real-time ultrasound monitoring is used to aid the insertion of cerebrospinal fluid (CSF) shunt ventricular catheters in children without patent fontanelles. Experience with the technique is reviewed. Intraoperative ultrasound is used to identify the compartments of the lateral ventricles and the choroid plexus prior to catheter insertion. Distance and trajectory to the best location for the hole-bearing segment of the catheter are determined and the catheter is inserted while real-time ultrasound monitoring is performed. Ten pediatric patients without open fontanelles underwent CSF shunt placement with the aid of transcranial ultrasound guidance between July and December 2006. After enlarging an occipital or frontal bur hole to a diameter of 2 cm to accommodate a small-footprint ultrasound probe, a ventricular catheter was carefully advanced into the frontal or occipital horn of the lateral ventricle while continuous ultrasound monitoring was performed. All catheters were inserted with a single pass through the brain. The final position of the ventricular catheter was visualized using intraoperative ultrasound. Postoperative computed tomography scans revealed all ventricular catheters placed accurately into the intended compartment of the ventricular system (for example, frontal horn or trigone). No procedure-related complications were noted. Real-time transcranial ultrasound monitoring through an enlarged bur hole is a feasible, safe, and effective technique for the placement of ventricular catheters in pediatric patients without a patent fontanelle.

Estimation of normal computed tomography measurements for the upper cervical spine in the pediatric age group.

OBJECT: Upper cervical spine injuries in the pediatric age group have been recognized as extremely unstable from ligamentous disruption and as potentially lethal. Few measurement norms have been published for the pediatric upper cervical spine to help diagnose this pathological state. Instead, adult measurement techniques and results are usually applied inappropriately to children. The authors propose using high-resolution reconstructed CT scans to define a range of normal for a collection of selected upper cervical spine measurements in the pediatric age group. METHODS: Sagittal and coronal reformatted images were obtained from thin axial CT scans obtained in 42 children (< 18 years) in a 2-month period. There were 25 boys and 17 girls. The mean age was 100.9 months (range 1-214 months). Six CT scans were obtained for nontrauma indications, and 36 were obtained as part of a trauma protocol and later cleared for cervical spine injury. Six straightforward and direct linear distances-basion-dental interval (BDI); atlantodental interval (ADI); posterior atlantodental interval (PADI); right and left lateral mass interval (LMI); right and left craniocervical interval (CCI); and prevertebral soft-tissue thickness at C-2-that minimized logistical and technical distortions were measured and recorded. Statistical analysis including interobserver agreement, age stratification, and sex differences was performed for each of the 6 measurements. RESULTS: The mean ADI was 2.25 ± 0.24 mm (± SD), the mean PADI was 18.3 ± 0.07 mm, the mean BDI was 7.28 ± 0.10 mm, and the mean prevertebral soft tissue width at C-2 was 4.45 ± 0.43 mm. The overall mean CCI was 2.38 ± 0.44 mm, and the overall mean LMI was 2.91 ± 0.49 mm. Linear regression analysis demonstrated statistically significant age effects for PADI (increased 0.02 mm/month), BDI (decreased 0.02 mm/month), and CCI (decreased 0.01 mm/month). Similarly significant effects were found for sex; females demonstrated on average a smaller CCI by 0.26 mm and a smaller PADI by 2.12 mm. Moderate to high interrater reliability was demonstrated across all parameters. CONCLUSIONS: Age-dependent and age-independent normal CT measurements of the upper cervical spine will help to differentiate physiological and pathological states in children. The BDI appears to change significantly with age but not sex; on the other hand, the LMI and ADI appear to be age-independent measures. This preliminary study suggests acceptable levels of interrater reliability, and further expanded study will aim to validate these measurements to produce a profile of normal upper cervical spine measurements in children.

Angioarchitectural features associated with hemorrhagic presentation in pediatric cerebral arteriovenous malformations.

BACKGROUND AND OBJECTIVE: To date, there have been few published studies examining the relationship between arteriovenous malformation (AVM) angioarchitecture and hemorrhagic presentation among children with cerebral AVMs. This study examines this relationship in this unique population, in whom symptomatic presentation of cerebral AVM is the norm rather than the exception. METHODS: A cohort of children with AVMs from 2000 to 2011 were included. Predictors studied included patient age, gender and angioarchitectural features, including AVM location, nidus size and morphology, venous drainage, presence of venous outflow lesions and associated aneurysms. Predictors of hemorrhagic presentation were assessed using multivariate logistic regression. RESULTS: 135 children (70 males, mean age 10.1 years) were included. 86/135 (63.7%) children presented with hemorrhage, 18 (13.3%) with seizures, 17 (12.6%) with headaches or neurological deficits and 14 (10.4%) were asymptomatic. AVM location, morphology and the presence of associated aneurysm, venous ectasia, draining vein stenosis and single draining vein were not significantly associated factors. After multivariate analysis, AVM size (OR 0.57, 95% CI 0.43 to 0.77; p<0.01), exclusive deep venous drainage (OR 4.94, 95% CI 1.30 to 18.8; p=0.02) and infratentorial location (OR 9.94, 95% CI 1.71 to 51.76; p=0.01) were independently associated with hemorrhagic presentation. CONCLUSION: Smaller AVM size, exclusive deep venous drainage and infratentorial location are specific angioarchitectural factors independently associated with initial hemorrhagic presentation in children with AVMs.

Trigeminal nerve integrated dose and pain outcome after gamma knife radiosurgery for trigeminal neuralgia.

BACKGROUND: Gamma knife radiosurgery (GKRS) is an established treatment for trigeminal neuralgia. Identifying factors that influence outcome will help improve patients' results. METHODS: We conducted a retrospective review of all patients treated with GKRS for trigeminal neuralgia at our institution from 2005 to 2010. Patients' clinical features and treatment details were reviewed. Analysis was performed to identify predictors of response and recurrence. RESULTS: A hundred and forty five patients were treated. Mean follow up period was 24 months. At last follow up, 48 patients (33%) were pain free with no medications, and 48 patients (33%) were pain free maintained on medications. Twenty-eight patients (19%) had pain after the treatment but had significant reduction in their pain severity. Twenty-one patients (15%) did not have any significant pain reduction. Forty-four patients (30%) developed facial numbness. Recurrence occurred in 51 patients (35%). Post-treatment numbness was a predictor of good treatment response (OR 2.720, CI 1.193-6.200, p 0.0173). Higher integrated dose was a predictor of poor pain response to radiosurgery (OR 0.729, CI 0.566-0.940, p 0.0146). At an integrated dose value of 5.3 mJ or less, there was more than 50% chance of pain free outcome. Longer pain duration prior to treatment was the only independent predictor of increased recurrence risk (HR 1.038, 95%CI 1.001-1.075; p=0.0412). CONCLUSIONS: Radiosurgery is an effective treatment modality for trigeminal neuralgia. Post treatment numbness is associated with good treatment response and higher integrated dose predicts poor outcome after radiosurgery for trigeminal neuralgia.