Risk of meningomyelocele mediated by the common 22q11.2 deletion.

Meningomyelocele is one of the most severe forms of neural tube defects (NTDs) and the most frequent structural birth defect of the central nervous system. We assembled the Spina Bifida Sequencing Consortium to identify causes. Exome and genome sequencing of 715 parent-offspring trios identified six patients with chromosomal 22q11.2 deletions, suggesting a 23-fold increased risk compared with the general population. Furthermore, analysis of a separate 22q11.2 deletion cohort suggested a 12- to 15-fold increased NTD risk of meningomyelocele. The loss of Crkl, one of several neural tube-expressed genes within the minimal deletion interval, was sufficient to replicate NTDs in mice, where both penetrance and expressivity were exacerbated by maternal folate deficiency. Thus, the common 22q11.2 deletion confers substantial meningomyelocele risk, which is partially alleviated by folate supplementation.

Pott Puffy Tumor Secondary to Cranial Vault Reconstruction in a Patient With Metopic Craniosynostosis.

Pott puffy tumor (PPT) is defined as a subperiosteal abscess of the anterior wall of the frontal sinus associated with underlying frontal osteomyelitis. PPT affects all age groups but occurs predominantly in adolescents. The potential etiologies include rhinosinusitis, a history of direct trauma to the forehead, odontogenic disease, intranasal drug abuse, diabetes, or other immunocompromised states. We introduce a case of a 6-year-old boy with a medical history of anterior cranial vault remodeling presenting with localized forehead swelling. Computed tomography imaging demonstrated mucosal thickening and a region of dehiscence in the wall of the frontal sinus; the presence of midline subperiosteal abscess was consistent with a diagnosis of PPT. Due to concerns for intracranial involvement, we utilized removal and replacement of the anterior wall of the frontal sinus, complete removal of sinus mucosa, and frontal sinus obliteration with bilateral peri-cranial flaps. To the best of our knowledge, this is the first case description of a PPT secondary to cranial vault reconstruction in a patient with metopic craniosynostosis.

Substance Abuse and Rural Appalachian Pediatric Trauma in West Virginia.

Introduction: Rural Appalachia is endemic to issues such as substance abuse, poverty, and lack of community support, all of which negatively influence health outcomes. The incidence of pediatric trauma as it relates to substance abuse is of concern in the region, where the rate of positive drug screens in pediatric trauma cases is higher than national average. Methods: The West Virginia statewide pediatric trauma database was analyzed in a retrospective cohort study for the years 2009-2019. Variables of interest included injury severity (assessed using Abbreviated Injury Scale (AIS)), drug screening results, and various measures of patient outcome. Results: The sample was divided into 2009-2016 presentations (n = 3,356) and 2017-2019 presentations (n = 1,182). Incidence of critical (AIS 5) head injuries (p = 0.007) and serious (AIS 3) neck injuries (p = 0.001) increased as time progressed. Days requiring ventilation increased from 3.1 in 2009-2016 to 6.3 in 2017-2019 (p < 0.001). Drug screens were obtained at a rate of 6.9% in 2009-2016 versus 23.3% in 2017-2019 (p < 0.001). Benzodiazepine use increased from 0.8% to 1.8% (p < 0.001), and opioid use increased from 1% to 4.9% (p < 0.001). Conclusion: The increasing severity of pediatric trauma and substance abuse in Appalachia is of significant concern. The use of respiratory drive-depressing drugs has risen, just as the severity of head and neck traumas has increased. These results emphasize the importance of targeted interventions in the rural pediatric population.

Incidence, Prevalence, and Outcomes of Pediatric Trauma in Rural Appalachia (West Virginia) From 2017 to 2019.

Background Appalachian rural pediatric trauma has its unique incidence, presentation, and distribution due to the mechanisms of injury, geographic location, access to care, and social issues.  Purpose To review, analyze, and understand pediatric trauma in West Virginia during the period 2017-2019. Materials and methods After institutional review board approval, the statewide trauma database was queried and analyzed in a retrospective cohort study for all pediatric trauma ages zero to 18 from 2017-2019 in the Appalachian regions one through four in West Virginia. The following were analyzed: gender, injury mechanism, Glasgow Coma Scale Score (GCS) at admission, injury severity score (ISS), toxicology screen results, hospital length of stay, duration of ventilatory support, number of procedures performed during admission, presence of non-accidental trauma, cardiac arrest, patient discharge disposition, and mortality. Results One-thousand eighty-two (1182) patients between the ages of zero to 18 were admitted to the trauma center. An average of 37% was female and 63% male. In the 11-18 age group, 24% were female and 76% were male. Most injuries were due to blunt force (89%), followed by penetrating injuries (7.2%) and burns (1.4%). The majority had minor or moderate injuries with 95% receiving a Glasgow Coma Scale (GCS) >13 and 72% listed as minor on the injury severity score (ISS). Children in ages 0-2 years had the highest proportion of poor (0-8) GCS scores, high ISS (>14) scores, most hospital admission days, most days on a ventilator, highest mortality, most pre-hospital cardiac arrests, child abuse, burns, and placement with child protective services. An average of 31% of children tested, and 17% in the age group of 0-2 had a positive toxicology screen. There were 3670 procedures done in total and the most common procedure performed was an ultrasound of the abdomen. Procedures were performed in 90% of the patients. Conclusions and relevance Based on our study, the zero to two-year-old pediatric trauma patients are most vulnerable to poor outcomes and may need targeted preventative interventions. Toxicology screens may need to be more widely implemented in pediatric trauma in the Appalachian region. Rural trauma in Appalachia has endemic issues related to substance abuse, poverty, and a lower degree of social support as compared to urban areas. Although the distribution of injury may follow a national distribution, mechanism, management, and outcomes can vary.

The "SHIFT" technique: Suprahepatic IntraFalciform tubing for placement of ventriculoperitoneal shunts.

Ventriculoperitoneal (VP) shunts in pediatric patients are an important aspect of management for patients with hydrocephalus and are fraught with complications. Surgical revision rates for VP shunts in the pediatric population are currently high, which necessitates innovation in operative techniques for placing VP shunts in attempt to decrease complication risks. Here we describe a novel approach for placement of VP shunts that we hypothesize can reduce potential morbidity among pediatric patients. By utilizing the falciform ligament of the liver and the suprahepatic recess to suspend and maintain the shunt, outcomes may portend fewer iatrogenic intra-abdominal injuries, enhanced ease of shunt removal, provide a large surface area for absorption of drained cerebrospinal fluid, and result in fewer adhesions secondary to device placement. We are referring to the operative technique as the "SupraHepatic IntraFalciform Tubing" (SHIFT) technique. In summary, the SHIFT shunt is fashioned by creating a window through the falciform ligament, inserting the shunt, and placing tubing in the suprahepatic recess.

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.

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.

Surgical relevance of pediatric skull base maturation for the far-lateral and extreme-lateral infrajugular transcondylar-transtubercular exposure approaches.

OBJECTIVE: Lesions of the foramen magnum, inferolateral-to-midclival areas, and ventral pons and medulla are often treated using a far-lateral or extreme-lateral infrajugular transcondylar-transtubercular exposure (ELITE) approach. The development and surgical relevance of critical posterior skull base bony structures encountered during these approaches, including the occipital condyle (OC), hypoglossal canal (HGC), and jugular tubercle (JT), are nonetheless poorly defined in the pediatric population. METHODS: Measurements from high-resolution CT scans were made of the relevant posterior skull base anatomy (HGC depth from posterior edge of the OC, OC and JT dimensions) from 60 patients (evenly distributed among ages 0-3, 4-7, 8-11, 12-15, 16-18, and > 18 years), and compared between laterality, sex, and age groups by using t-tests and linear regression. RESULTS: There were no significant differences in posterior skull base parameters by laterality, and HGC depth and JT size did not differ by sex. The OC area was significantly larger in males versus females (174.3 vs 152.2 mm2; p = 0.01). From ages 0-3 years to adult, the mean HGC depth increased 27% (from 9.0 to 11.4 mm) and the OC area increased 52% (from 121.4 to 184.0 mm2). The majority of growth for these parameters occurred between the 0-3 year and 4-7 year age groups. Conversely, JT volume increased nearly 3-fold (281%) from 97.4 to 370.9 mm3 from ages 0-3 years to adult, with two periods of substantial growth seen between the 0-3 to 4-7 year and the 12-15 to 16-18 year age groups. Overall, JT growth during pediatric development was significantly greater than increases in HGC depth and OC area (p < 0.05). JT volume remained < 65% of adult size up to age 16. CONCLUSIONS: When considering a far-lateral or ELITE approach in pediatric patients, standard OC drilling is likely to be needed due to the relative stability of OC and HGC anatomy during development. The JT significantly increases in size with development, yet is only likely to need to be drilled in older children (> 16 years) and adults.

Pediatric Intracavernous Sinus Lesions: A Single Institutional Surgical Case Series and Review of the Literature.

BACKGROUND: Pediatric intracavernous sinus tumors are exceedingly rare and thus poorly characterized. Their neurosurgical management is challenging and diagnostic, and management guidelines are limited. OBJECTIVE: To report our institutional experience with the surgical resection of pediatric intracavernous sinus tumors. We also compare and contrast our results with the 14 cases of pediatric intracavernous sinus lesions in the current literature. METHODS: A retrospective descriptive analysis of consecutive pediatric patients (ages 0-18 yr) presenting to our institution with a diagnosis of an intracavernous sinus lesion was performed. From January 2012 to January 2017, 5 cases were identified. Eleven patients with secondary invasion of the cavernous sinus (2 meningiomas, 7 pituitary adenomas) or dermoid tumors involving the cavernous sinus (2) were not included in our review. RESULTS: Surgical resection via a frontotemporal orbitozygomatic approach was performed in all cases by a single senior neurosurgeon (M.L.). There were no perioperative or postoperative complications attributable to the surgery or approach. Four of 5 patients remained neurologically stable throughout the perioperative and postoperative period. The fifth patient had a complete resolution of their cranial neuropathies postoperatively. A pathological diagnosis that guided long-term management was obtained in all cases. CONCLUSION: Neurosurgical management of pediatric cavernous sinus lesions can be safely performed and critically guide future therapies. Surgeon familiarity with cavernous sinus and skull-base anatomy is critical to the successful management of these patients. The benefits of surgery should be balanced against the potential complications and need for a tissue diagnosis in children. The senior author had a significant experience with cavernous sinus approaches in adults prior to initiating use of the approach in the pediatric population.

Distraction Osteogenesis for Unicoronal Craniosynostosis: Rotational Flap Technique and Case Series.

BACKGROUND: The limitations of the soft-tissue envelope, devascularized bone grafts, and relapse of the deformity are important considerations in the surgical treatment of unicoronal craniosynostosis. The authors report their technique evolution of distraction osteogenesis for treatment of patients with unicoronal craniosynostosis. METHODS: Open anterior cranial vault reconstruction combined with internal distraction was used, with the aid of virtual surgical planning. Technique evolution included maximizing bone flap perfusion by means of limited rotational flap osteotomies, and preservation of dural attachments. Clinical and procedural characteristics including distraction protocol, intracranial volume change, efficiency of distraction, transfusion, operative time, length of hospitalization, complications, and postoperative outcomes were analyzed. RESULTS: Sixteen patients with nonsyndromic unicoronal craniosynostosis underwent repair between August of 2013 and December of 2016. Mean age was 9.0 months. Distractors were advanced a mean of 27.1 mm and achieved a cranial volume change of 29.5 percent, with a mean efficiency of 1.3 percent increase per millimeter of distraction. Mean operating time was 169.3 minutes. Complications were predominately related to infections at the distractor site. At most recent follow-up, all patients had a Whitaker grade I result. CONCLUSIONS: Distraction osteogenesis can be a safe and effective method of achieving satisfactory aesthetic outcomes and volume expansion for patients with unicoronal craniosynostosis. The technique presented is proposed to maximize bone flap viability and limit relapse of deformity. Further long-term follow-up is needed for definitive comparison with traditional anterior cranial vault reconstruction. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The identification of a subgroup of children with traumatic subarachnoid hemorrhage at low risk of neuroworsening.

OBJECTIVEPediatric traumatic subarachnoid hemorrhage (tSAH) often results in intensive care unit (ICU) admission, the performance of additional diagnostic studies, and ICU-level therapeutic interventions to identify and prevent episodes of neuroworsening.METHODSData prospectively collected in an institutionally specific trauma registry between 2006 and 2015 were supplemented with a retrospective chart review of children admitted with isolated traumatic subarachnoid hemorrhage (tSAH) and an admission Glasgow Coma Scale (GCS) score of 13-15. Risk of blunt cerebrovascular injury (BCVI) was calculated using the BCVI clinical prediction score.RESULTSThree hundred seventeen of 10,395 pediatric trauma patients were admitted with tSAH. Of the 317 patients with tSAH, 51 children (16%, 23 female, 28 male) were identified with isolated tSAH without midline shift on neuroimaging and a GCS score of 13-15 at presentation. The median patient age was 4 years (range 18 days to 15 years). Seven had modified Fisher grade 3 tSAH; the remainder had grade 1 tSAH. Twenty-six patients (51%) had associated skull fractures; 4 involved the petrous temporal bone and 1 the carotid canal. Thirty-nine (76.5%) were admitted to the ICU and 12 (23.5%) to the surgical ward. Four had an elevated BCVI score. Eight underwent CT angiography; no vascular injuries were identified. Nine patients received an imaging-associated general anesthetic. Five received hypertonic saline in the ICU. Patients with a modified Fisher grade 1 tSAH had a significantly shorter ICU stay as compared to modified Fisher grade 3 tSAH (1.1 vs 2.5 days, p = 0.029). Neuroworsening was not observed in any child.CONCLUSIONSChildren with isolated tSAH without midline shift and a GCS score of 13-15 at presentation appear to have minimal risk of neuroworsening despite the findings in some children of skull fractures, elevated modified Fisher grade, and elevated BCVI score. In this subgroup of children with tSAH, routine ICU-level care and additional diagnostic imaging may not be necessary for all patients. Children with modified Fisher grade 1 tSAH may be particularly unlikely to require ICU-level admission. Benefits to identifying a subgroup of children at low risk of neuroworsening include improvement in healthcare efficiency as well as decreased utilization of unnecessary and potentially morbid interventions, including exposure to ionizing radiation and general anesthesia.

Endoscopic surgery for nonsyndromic craniosynostosis: a 16-year single-center experience.

OBJECTIVE: In this paper the authors review their 16-year single-institution consecutive patient experience in the endoscopic treatment of nonsyndromic craniosynostosis with an emphasis on careful review of any associated treatment-related complications and methods of complication avoidance, including preoperative planning, intraoperative management, and postoperative care and follow-up. METHODS: A retrospective chart review was conducted on all patients undergoing endoscopic, minimally invasive surgery for nonsyndromic craniosynostosis at Rady Children's Hospital from 2000 to 2015. All patients were operated on by a single neurosurgeon in collaboration with two plastic and reconstructive surgeons as part of the institution's craniofacial team. RESULTS: Two hundred thirty-five patients underwent minimally invasive endoscopic surgery for nonsyndromic craniosynostosis from 2000 to 2015. The median age at surgery was 3.8 months. The median operative and anesthesia times were 55 and 105 minutes, respectively. The median estimated blood loss (EBL) was 25 ml (median percentage EBL 4.2%). There were no identified episodes of air embolism or operative deaths. One patient suffered an intraoperative sagittal sinus injury, 2 patients underwent intraoperative conversion of planned endoscopic to open procedures, 1 patient experienced a dural tear, and 1 patient had an immediate reexploration for a developing subgaleal hematoma. Two hundred twenty-five patients (96%) were admitted directly to the standard surgical ward where the median length of stay was 1 day. Eight patients were admitted to the intensive care unit (ICU) postoperatively, 7 of whom had preexisting medical conditions that the team had identified preoperatively as necessitating a planned ICU admission. The 30-day readmission rate was 1.7% (4 patients), only 1 of whom had a diagnosis (surgical site infection) related to their initial admission. Average length of follow-up was 2.8 years (range < 1 year to 13.4 years). Six children (< 3%) had subsequent open procedures for perceived suboptimal aesthetic results, 4 of whom (> 66%) had either coronal or metopic craniosynostosis. No patient in this series either presented with or subsequently developed signs or symptoms of intracranial hypertension. CONCLUSIONS: In this large single-center consecutive patient series in the endoscopic treatment of nonsyndromic craniosynostosis, significant complications were avoided, allowing for postoperative care for the vast majority of infants on a standard surgical ward. No deaths, catastrophic postoperative morbidity, or evidence of the development of symptomatic intracranial hypertension was observed.

Intracranial Hypotension and Hypertension Associated With Reconstructive Cranioplasty After Decompressive Craniectomy: Report of a Lethal Complication With Recommended Strategies for Future Avoidance.

Reconstructive cranioplasty can be associated with many complications and add to the not insignificant potential risks associated with decompressive craniectomy. In the setting of post-traumatic hydrocephalus, treatment with a ventriculoperitoneal (VP) shunt prior to reconstructive cranioplasty likely increases these risks even further. The authors report a case of a 17-year-old male with a history of a severe closed head injury who initially suffered a life-threatening complication associated with intracranial hypotension after cranioplasty only to succumb to malignant intracranial hypertension following a second cranioplasty attempt. To our knowledge, this is the first description of a single patient developing both these disparate complications after reconstructive cranioplasty and emphasizes the likely synergistic hazards involved with decompressive craniectomy in the setting of a VP shunt in particular and the overall myriad potential complications that may be associated with reconstructive cranioplasty in general.

Predictors of Postoperative Complications of Craniosynostosis Repair in the National Inpatient Sample.

INTRODUCTION: Timing of intervention and complication profiles in surgical repair of craniosynostosis have been widely debated. Early intervention is frequently promoted as a means of decreasing morbidity while maintaining favorable outcomes via minimally invasive techniques such as endoscopic strip craniectomy. Immediate postoperative morbidity due to complications of early vs late intervention remains a key element in comparing timing and technique for craniosynostosis repair. In addition, concurrent fronto-orbital advancement with open cranial vault remodeling may increase the risk of postoperative complications. We present an evaluation of surgical timing and the presence of fronto-orbital advancement as independent predictors of in-hospital complications after craniosynostosis repair. METHODS: Retrospective analysis was performed in the National Inpatient Sample database from 1998 to 2009. Patients younger than 3 years having undergone elective surgical repair for craniosynostosis were identified. Comorbidities, demographics, transfusion status, and syndromic diagnosis were included as covariates. A multivariate regression model was used to characterize the association between age at the time of surgery and in-hospital complications. A subgroup analysis using the variable of concurrent fronto-orbital advancement was restricted to patients 8 to 24 months of age to exclude endoscopic craniosynostosis repair, which is traditionally repaired less than 6 months of age. Multivariate logistic regression was used to assess the impact of concurrent fronto-orbital advancement on postoperative complications. RESULTS: A total of 6010 craniosynostosis surgery cases (42.9%, age 0-7 months; 29.5%, age 8-12 months; and 27.6%, age 13-36 months) were included. Patients in the 7-to 12-month age group were more likely to experience complications when compared with the 0- to 6-month age group (odds ratio [OR],1.32; P < 0.05) and 13-to 36-month age group (OR, 1.32; P = 0.056). Syndromic patients (OR, 1.92; P < 0.001) and patients receiving an intraoperative blood transfusion (OR, 1.60; P < 0.05) demonstrated an increased risk for complications. In the subanalysis of 2936 patients aged 8 to 24 months, 15.1% of patients received frontoorbital advancement, which was associated with a significantly increased risk of complications (OR, 1.43; P < 0.05). CONCLUSIONS: Intermediate age (7-12 months) and concurrent fronto-orbital repair were independent risk factors for immediate postoperative complications. These findings may better inform the decision-making process for craniosynostosis repair in terms of timing and need for concurrent fronto-orbital reconstruction.

A Novel Method for Quantifying Intracranial Volume Change by Distraction Osteogenesis for Craniosynostosis.

INTRODUCTION: Methods of reporting quantitative results for distraction osteogenesis (DO) of craniosynostosis have been inconsistent. Therefore, the efficacy of differing techniques and timing in regard to volume change is not well established, with no uniform metric for comparisons. Given that cranial vault remodeling with DO may be completed with different approaches, analysis was made to determine (1) the relative efficiency of different approaches in expanding intracranial volume (ICV) and (2) the impact of adjusting for ICV growth on measured DO efficiency. METHODS: Patients with craniosynostosis were treated with open cranial vault reconstruction combined with internal distraction. Preoperative and postoperative computed tomography scans were used to quantify ICV change. The metric was determined by dividing percent ICV change by total distraction length. The metric was used as a proxy for efficiency to compare posterior and anterior distraction between groups using the Mann-Whitney U test and within a subgroup of patients who underwent 2-stage distraction using the Wilcoxon matched-pairs signed rank test. RESULTS: Twenty patients underwent cranial vault remodeling with DO: 14 unicoronal, 3 bicoronal, 2 multisutural, and 1 lambdoid. Results are reported in medians. Distraction efficiency was 0.99%/mm for primary anterior, unilateral distraction for unicoronal patients (n = 13, aged 9.1 months) and 4.28%/mm for posterior distraction using multiple distractors (n = 4, aged 6.3 months). In terms of the metric, primary posterior distraction was significantly more efficient than primary anterior distraction (P = 0.007). Three patients who had undergone primary posterior distraction later underwent secondary anterior distraction. Again, posterior distraction was shown to be significantly more efficient (5.16 vs 0.62, P = 0.050). For the unicoronal patients who received anterior unilateral distraction, an adjusted metric was calculated to account for normal intracranial growth. This was found to be 0.39%/mm, which was significantly different from the unadjusted metric (P = 0.0001). CONCLUSIONS: Posterior distraction is more efficient for ICV expansion than anterior distraction, which may have implications for the choice of approach for craniosynostosis repair. In addition, this is the first report of a novel standardized metric for analyzing ICV change achieved by DO. This tool allows for adjusting the efficiency metric for expected ICV growth, which significantly impacts its value.

Extended middle fossa approach to lateralized pontine cavernomas in children.

OBJECTIVE Treatment of hemorrhagic cavernous malformations within the lateral pontine region demands meticulous surgical planning and execution to maximize resection while minimizing morbidity. The authors report a single institution's experience using the extended middle fossa rhomboid approach for the safe resection of hemorrhagic cavernomas involving the lateral pons. METHODS A retrospective chart review was performed to identify and review the surgical outcomes of patients who underwent an extended middle fossa rhomboid approach for the resection of hemorrhagic cavernomas involving the lateral pons during a 10-year period at Rady Children's Hospital of San Diego. Surgical landmarks for this extradural approach were based on the Fukushima dual-fan model, which defines the rhomboid based on the following anatomical structures: 1) the junction of the greater superficial petrosal nerve (GSPN) and mandibular branch of the trigeminal nerve; 2) the lateral edge of the porus trigeminus; 3) the intersection of the petrous ridge and arcuate eminence; and 4) the intersection of the GSPN, geniculate ganglion, and arcuate eminence. The boundaries of maximal bony removal for this approach are the clivus inferiorly below the inferior petrosal sinus; unroofing of the internal auditory canal posteriorly; skeletonizing the geniculate ganglion, GSPN, and internal carotid artery laterally; and drilling under the Gasserian ganglion anteriorly. This extradural petrosectomy allowed for an approach to all lesions from an area posterolateral to the basilar artery near its junction with cranial nerve (CN) VI, superior to the anterior inferior cerebellar artery and lateral to the origin of CN V. Retraction of the mandibular branch of the trigeminal nerve during this approach allowed avoidance of the region involving CN IV and the superior cerebellar artery. RESULTS Eight pediatric patients (4 girls and 4 boys, mean age of 13.2 ± 4.6 years) with hemorrhagic cavernomas involving the lateral pons and extension to the pial surface were treated using the surgical approach described above. Seven cavernomas were completely resected. In the eighth patient, a second peripheral lesion was not resected with the primary lesion. One patient had a transient CN VI palsy, and 2 patients had transient trigeminal hypesthesia/dysesthesia. One patient experienced a CSF leak that was successfully treated by oversewing the wound. CONCLUSIONS The extended middle fossa approach can be used for resection of lateral pontine hemorrhagic cavernomas with minimal morbidity in the pediatric population.

Robot-assisted endoscopic third ventriculostomy: institutional experience in 9 patients.

OBJECTIVE The endoscopic third ventriculostomy (ETV) is an established and effective treatment for obstructive hydrocephalus. In its most common application, surgeons plan their entry point and the endoscope trajectory for the procedure based on anatomical landmarks, then control the endoscope freehand. Recent studies report an incidence of neural injuries as high as 16.6% of all ETVs performed in North America. The authors have introduced the ROSA system to their ETV procedure to stereotactically optimize endoscope trajectories, to reduce risk of traction on neural structures by the endoscope, and to provide a stable mechanical holder of the endoscope. Here, they present their series in which the ROSA system was used for ETVs. METHODS At the authors' institution, they performed ETVs with the ROSA system in 9 consecutive patients within an 8-month period. Patients had to have a favorable expected response to ETV (ETV Success Score ≥ 70) with no additional endoscopic procedures (e.g., choroid plexus cauterization, septum pellucidum fenestration). The modality of image registration (CT, MRI, surface mapping, or bone fiducials) was dependent on the case. RESULTS Nine pediatric patients with an age range of 1.5 to 16 years, 4 girls and 5 boys, with ETV Success Scores ranging from 70 to 90, underwent successful ETV surgery with the ROSA system within an 8-month period. Their intracranial pathologies included tectal tumors (n = 3), communicating hydrocephalus from hemorrhage or meningeal disease (n = 2), congenital aqueductal stenosis (n = 1), compressive porencephalic cyst (n = 1), Chiari I malformation (n = 1), and pineal region mass (n = 1). Robotic assistance was limited to the ventricular access in the first 2 procedures, but was used for the entirety of the procedure for the following 7 cases. Four of these cases were combined with another procedural objective (3 stereotactic tectal mass biopsies, 1 Chiari decompression). A learning curve was observed with each subsequent surgery as registration and surgical times became shorter and more efficient. All patients had complete resolution of their preprocedural symptoms. There were no complications. CONCLUSIONS The ROSA system provides a stable, precise, and minimally invasive approach to ETVs.

Impact of ventricular-peritoneal shunt valve design on clinical outcome of pediatric patients with hydrocephalus: Lessons learned from randomized controlled trials.

Hydrocephalus is one of the most common diseases managed by pediatric neurosurgeons. Cerebrospinal fluid (CSF) shunting has been the mainstay of durable treatment for hydrocephalus for many decades. There are two main categories of shunt designs for regulating the extent of CSF diversion: (1) Fixed-parameter valves and (2) adjustable valves. Furthermore, these valves can also function with and without an anti-siphon device. Here, we review randomized controlled trials (RCTs) that examined the impact of these valve designs on the clinical outcome of pediatric patients afflicted with hydrocephalus. All three RCTs suggested no significant differences in clinical outcome as a function of shunt design. Implications of these findings are discussed.

Reverse Distraction Cranioplasty for Treatment of Hydrocephalic Megalocephaly.

Macrocephaly resulting from untreated hydrocephalus is a rare but difficult condition to treat. The patient presented is a 6-year-old boy who had progressively increasing head size since birth secondary to untreated hydrocephalus with associated developmental delay. His initial head circumference was 69 cm, and computed tomography scan showed evidence of obstructive hydrocephalus. For the first stage of the procedure, bicoronal and circumferential strip craniectomies were performed, 5 fully open 3.5 mm midface distractors were placed to facilitate vault reduction, and absorbable plates were placed in the frontoorbital region. Neurosurgery also performed an endoscopic third ventriculostomy and placed an external ventricular drain. Reverse distraction was completed over 5 days and tolerated well by the patient. Three months after the first procedure, the distractors were removed and frontoorbital reduction and additional cranial vault reduction and reshaping were performed. At 1 month following this operation he was noted to have excellent forehead contour and dramatic improvement of his macrocephaly with some remaining mid-vault asymmetry. His head circumference was measured at 61.5 cm with bicoronal distance of 39.5 cm. He demonstrated improvement in head control and ability to sit. This patient demonstrates a new technique for reduction cranioplasty involving the use of reverse distraction to facilitate gradual and controlled reduction prior to extensive cranial vault remodeling. The challenges associated with managing hydrocephalus in cranial vault reduction patients are also addressed.