Spontaneous thrombosis of high flow pediatric arteriovenous fistulae: Case series of two patients and a comprehensive literature review.

Pediatric pial arteriovenous shunts in the brain and spine are challenging to understand because of low incidence, variable presentation, and associations with genetic syndromes. What is known about their natural history comes from reviews of small series. To better understand the natural history and role for intervention, two cases are presented followed by a review of the literature. In the first case, an infant with a prior history of intracranial hemorrhage from a ruptured pial fistula returns for elective embolization for a second pial fistula which was found to be spontaneously thrombosed 2 weeks later. In the second case, a 5-year-old with a vertebro-vertebral fistula, identified on work up for a heart murmur and documented with diagnostic angiography, is brought for elective embolization 6 weeks later where spontaneous thrombosis is identified. In reviewing the literature on pediatric single-hole fistulae of the brain and spine, the authors offer some morphologic considerations for identifying which high-flow fistulae may undergo spontaneous thrombosis to decrease the potentially unnecessary risk associated with interventions in small children.

Pediatric Moyamoya Revascularization Perioperative Care: A Modified Delphi Study.

BACKGROUND: Surgical revascularization decreases the long-term risk of stroke in children with moyamoya arteriopathy but can be associated with an increased risk of stroke during the perioperative period. Evidence-based approaches to optimize perioperative management are limited and practice varies widely. Using a modified Delphi process, we sought to establish expert consensus on key components of the perioperative care of children with moyamoya undergoing indirect revascularization surgery and identify areas of equipoise to define future research priorities. METHODS: Thirty neurologists, neurosurgeons, and intensivists practicing in North America with expertise in the management of pediatric moyamoya were invited to participate in a three-round, modified Delphi process consisting of a 138-item practice patterns survey, anonymous electronic evaluation of 88 consensus statements on a 5-point Likert scale, and a virtual group meeting during which statements were discussed, revised, and reassessed. Consensus was defined as ≥ 80% agreement or disagreement. RESULTS: Thirty-nine statements regarding perioperative pediatric moyamoya care for indirect revascularization surgery reached consensus. Salient areas of consensus included the following: (1) children at a high risk for stroke and those with sickle cell disease should be preadmitted prior to indirect revascularization; (2) intravenous isotonic fluids should be administered in all patients for at least 4 h before and 24 h after surgery; (3) aspirin should not be discontinued in the immediate preoperative and postoperative periods; (4) arterial lines for blood pressure monitoring should be continued for at least 24 h after surgery and until active interventions to achieve blood pressure goals are not needed; (5) postoperative care should include hourly vital signs for at least 24 h, hourly neurologic assessments for at least 12 h, adequate pain control, maintaining normoxia and normothermia, and avoiding hypotension; and (6) intravenous fluid bolus administration should be considered the first-line intervention for new focal neurologic deficits following indirect revascularization surgery. CONCLUSIONS: In the absence of data supporting specific care practices before and after indirect revascularization surgery in children with moyamoya, this Delphi process defined areas of consensus among neurosurgeons, neurologists, and intensivists with moyamoya expertise. Research priorities identified include determining the role of continuous electroencephalography in postoperative moyamoya care, optimal perioperative blood pressure and hemoglobin targets, and the role of supplemental oxygen for treatment of suspected postoperative ischemia.

Radiologic and clinical outcome of isolated fourth ventricle following post-hemorrhagic hydrocephalus in children.

PURPOSE: Few studies report radiologic and clinical outcome of post-hemorrhagic isolated fourth ventricle (IFV) with focus on surgical versus conservative management in neonates and children. Our aim is to investigate differences in radiological and clinical findings of IFV between patients who had surgical intervention versus patients who were treated conservatively. METHODS: A retrospective analysis of patients diagnosed with IFV was performed. Data included demographics, clinical exam findings, surgical history, and imaging findings (dilated FV extent, supratentorial ventricle dilation, brainstem and cerebellar deformity, tectal plate elevation, basal cistern and cerebellar hemisphere effacement, posterior fossa upward/downward herniation). RESULTS: Sixty-four (30 females) patients were included. Prematurity was 94% with 90% being < 28 weeks of gestation. Mean age at first ventricular shunt was 3.6 (range 1-19); at diagnosis of IFV, post-lateral ventricular shunting was 26.2 (1-173) months. Conservatively treated patients were 87.5% versus 12.5% treated with FV shunt/endoscopic fenestration. Severe FV dilation (41%), severe deformity of brainstem (39%) and cerebellum (47%) were noted at initial diagnosis and stable findings (34%, 47%, and 52%, respectively) were seen at last follow-up imaging. FV dilation (p = 0.0001) and upward herniation (p = 0.01) showed significant differences between surgery versus conservative management. No other radiologic or clinical outcome parameters were different between two groups. CONCLUSION: Only radiologic outcome results showed stable or normal FV dilation and stable or decreased upward herniation in the surgically treated group.

Maximizing the subtonsillar transcerebellomedullary approach to suprasellar cistern: how I do it.

BACKGROUND: The subtonsillar transcerebellomedullary approach (STA) has been well established as one of the surgical options to access lesions in the foramen of Luschka. The middle cerebellar peduncle has been defined as the superior limit of this corridor, and tumors extending beyond this landmark were often approached through combined accesses. METHOD: We illustrate the access to the suprasellar cistern, from a purely STA for a large tumor arising from the foramen of Luschka. CONCLUSION: This manuscript demonstrates the STA as a valid alternative for certain tumors of the foramen of Luschka, which extend into crural and suprasellar cisterns.

Incidence of delayed intracranial hypertension in children with isolated sagittal synostosis following open calvarial vault reconstruction.

PURPOSE: Delayed intracranial hypertension (DIH) occurs most frequently in children with syndromic or multi-suture synostosis after surgical correction. The rarity of DIH in children with isolated non-syndromic sagittal synostosis (ISS) warrants follow-up evaluation by large craniofacial centers until skeletal maturity. This study reports the incidence of DIH in children following open repair for ISS by our center's craniofacial team. METHODS: A single-center retrospective study of patients who underwent open calvarial vault remodeling (CVR) for ISS at our institution between November 2000 and November 2012 was performed. Syndromic and multi-suture synostosis patients were excluded. Demographic and follow-up data were extracted from the medical record for analysis until July 2017. RESULTS: One hundred five patients with ISS were identified who had undergone CVR in the aforementioned timeframe. Average age at initial surgery was 11.7 ± 15.32 months. Mean follow-up in our craniofacial clinic was 4.94 ± 3.53 years, with 69 patients (65.7%) having follow-up in craniofacial clinic ≥ 3 years and 74 (70.5%) having follow-up ≥ 3 years in any clinic at our institution. Four patients (3.8%) had intracranial pressure (ICP) monitors placed for symptoms concerning for DIH, one of which (0.95%) had confirmed DIH and underwent a second surgical procedure at 7.4 years of age. The patient presented late initially, having his first operation at 1.56 years of age. CONCLUSION: One patient out of 105 (0.95%) developed DIH, confirmed by ICP monitoring, and required reoperation. The occurrence of DIH, albeit rare, remains an important topic to include in parental discussions and mandates long-term follow-up in this population.

Surgical treatment of epilepsy in Vietnam: program development and international collaboration.

OBJECTIVE: The purpose of this report was to describe an international collaboration model to facilitate the surgical treatment of children with epilepsy in Vietnam. METHODS: This model uses three complementary methods to achieve a meaningful expansion in epilepsy surgery capacity: US-based providers visiting Hanoi, Vietnam; Vietnamese providers visiting the US; and ongoing telecollaboration, including case review and real-time mentorship using internet-based communication platforms. RESULTS: Introductions took place during a US neurosurgeon's visit to Vietnam in 2014. Given the Vietnamese surgeon's expertise in intraventricular tumor surgery, the focus of the initial visit was corpus callosotomy. After two operations performed jointly, the Vietnamese surgeon went on to perform 10 more callosotomy procedures in the ensuing 6 months with excellent results. The collaborative work grew and matured in 2016-2017, with 40 pediatric epilepsy surgeries performed from 2015 through 2017. Because pediatric epilepsy care requires far more than neurosurgery, teams traveling to Vietnam included a pediatric neurologist and an electroencephalography (EEG) technologist. Also, in 2016-2017, a neurosurgeon, two neurologists, and an EEG nurse from Vietnam completed 2- to 3-month fellowships at Children's of Alabama (COA) in the US. These experiences improved EEG capabilities and facilitated the development of intraoperative electrocorticography (ECoG), making nonlesional epilepsy treatment more feasible. The final component has been ongoing, i.e., regular communication. The Vietnamese team regularly sends case summaries for discussion to the COA epilepsy conference. Three patients in Vietnam have undergone resection guided by ECoG without the US team present, although there was communication via internet-based telecollaboration tools between Vietnamese and US EEG technologists. To date, two of these three patients remain seizure free. The Vietnamese team has presented the results of their epilepsy experience at two international functional and epilepsy surgery scientific meetings. CONCLUSIONS: Ongoing international collaboration has improved the surgical care of epilepsy in Vietnam. Experience suggests that the combination of in-country and US-based training, augmented by long-distance telecollaboration, is an effective paradigm for increasing the capacity for highly subspecialized, multidisciplinary neurosurgical care.

A comparison of the MOMS trial results to a contemporaneous, single-institution, postnatal closure cohort.

PURPOSE: We evaluate a single-institution cohort of mothers contemporaneous with the Management of Myelomeningocele Study (MOMS) trial to determine the generalizability of MOMS results and compare shunt rates. METHODS: A retrospective chart review identified patients with myelomeningocele born between 2003 and 2009. We applied MOMS eligibility criteria and compared sociodemographic variables between patients at our institution who would have been eligible or ineligible and MOMS participants. Finally, we applied the original MOMS primary outcome and the revised primary outcome to our cohort. RESULTS: Of the 78 patients, 55 (70.5%) were eligible for the MOMS trial. Mean maternal age, race, and marital status were different from both MOMS groups. Comparing our series to MOMS postnatal shows fewer female infants (44.9 vs. 63.8%, p = 0.017) and more thoracic lesions (12.8 vs. 3.8%, p = 0.038). Shunt rates in our cohort (84.6%) were higher than MOMS prenatal and similar to MOMS postnatal (44.0 and 83.7%, respectively). Fewer children met the original primary outcome than the postnatal group (84.6 vs. 97.8%, p = 0.002). There was no significant difference between our cohort and the prenatal group (84.6 vs. 72.5%, p = 0.058). When applying the revised criteria, we find the opposite: a significant difference between local and MOMS prenatal (84.6 vs. 49.5%, p < 0.001) but no difference between the local group and MOMS postnatal (84.6 vs. 87.0%, p = 0.662). CONCLUSIONS: Mothers in our cohort differ from mothers enrolled in MOMS via several sociodemographic factors. Baseline fetal characteristics show a significantly higher functional lesion level in between our cohort and MOMS. Treatment of hydrocephalus in our series tracks almost identically with original MOMS shunt criteria. Revision of the criteria led to greater concordance between meeting criteria and receiving a shunt in MOMS patients, but changes the results in our series.

MEK signaling represents a viable therapeutic vulnerability of KRAS-driven somatic brain arteriovenous malformations.

Brain arteriovenous malformations (bAVMs) are direct connections between arteries and veins that remodel into a complex nidus susceptible to rupture and hemorrhage. Most sporadic bAVMs feature somatic activating mutations within KRAS, and endothelial-specific expression of the constitutively active variant KRASG12D models sporadic bAVM in mice. By leveraging 3D-based micro-CT imaging, we demonstrate that KRASG12D-driven bAVMs arise in stereotypical anatomical locations within the murine brain, which coincide with high endogenous Kras expression. We extend these analyses to show that a distinct variant, KRASG12C, also generates bAVMs in predictable locations. Analysis of 15,000 human patients revealed that, similar to murine models, bAVMs preferentially occur in distinct regions of the adult brain. Furthermore, bAVM location correlates with hemorrhagic frequency. Quantification of 3D imaging revealed that G12D and G12C alter vessel density, tortuosity, and diameter within the mouse brain. Notably, aged G12D mice feature increased lethality, as well as impaired cognition and motor function. Critically, we show that pharmacological blockade of the downstream kinase, MEK, after lesion formation ameliorates KRASG12D-driven changes in the murine cerebrovasculature and may also impede bAVM progression in human pediatric patients. Collectively, these data show that distinct KRAS variants drive bAVMs in similar patterns and suggest MEK inhibition represents a non-surgical alternative therapy for sporadic bAVM.

Racial differences in the care of pediatric sagittal craniosynostosis: a single-institution cohort study affecting state Medicaid policy.

OBJECTIVE: Although research has shown the cost-effectiveness of endoscopic versus open repair of sagittal synostosis, few studies have shown how race, insurance status, and area deprivation impact care for these patients. The authors analyzed data from children evaluated for sagittal synostosis at a single institution to assess how socioeconomic factors, race, and insurance status affect the surgical treatment of this population. They hypothesized that race and indicators of disadvantage negatively impact workup and surgical timing for craniosynostosis surgery. METHODS: Medical records of patients treated for sagittal synostosis between 2010 and 2019 were reviewed. Area deprivation index (ADI) and rural-urban commuting area codes, as well as median income by zip code, were used to measure neighborhood disadvantage. Black and White patients were compared as well as patients using Medicaid versus private insurance. RESULTS: Fifty patients were prospectively included in the study. Thirty-one underwent open repair; 19 had endoscopic repair. All 8 (100%) Black patients had open repair, compared to 54.8% of White patients (p = 0.018). Black patients were more likely to use Medicaid compared to White patients (75.0% vs 28.6%, p = 0.019). White patients were younger at surgery (5.5 vs 10.0 months, p = 0.001), and Black patients had longer surgeries (147.5 minutes vs 110.0 minutes, p = 0.021). The median household income by zip code was similar for the two groups. Black patients were generally from areas of greater disadvantage compared to White patients, based on both state and national ADI scores (state: 7.5 vs 4.0, p = 0.013; national: 83.5 vs 60.0, p = 0.013). All (94.7%) but 1 patient undergoing endoscopic repair used private insurance compared to 14 (45.2%) patients in the open repair group (p = 0.001). Patients using Medicaid were from areas of greater disadvantage compared to those using private insurance by both state and national ADI scores (state: 6.0 vs 3.0, p = 0.001; national: 75.0 vs 52.0, p = 0.001). CONCLUSIONS: Because Medicaid in the geographic region of this study did not cover helmeting after endoscopic repair of sagittal synostosis, these patients usually had open repair, resulting in significant racial and socioeconomic disparities in treatment of sagittal synostosis. This research has led to a change in Alabama Medicaid policy to now cover the cost of postoperative helmeting.

Germline genetic mutations in pediatric cerebrovascular anomalies: a multidisciplinary approach to screening, testing, and management.

OBJECTIVE: Genetic alterations are increasingly recognized as etiologic factors linked to the pathogenesis and development of cerebrovascular anomalies. Their identification allows for advanced screening and targeted therapeutic approaches. The authors aimed to describe the role of a collaborative approach to care and genetic testing in pediatric patients with neurovascular anomalies, with the objectives of identifying what genetic testing recommendations were made, the yield of genetic testing, and the implications for familial screening and management at present and in the future. METHODS: The authors performed a descriptive retrospective cohort study examining pediatric patients genetically screened through the Pediatric Neurovascular Program of a single treatment center. Patients 18 years of age and younger with neurovascular anomalies, diagnosed radiographically or histopathologically, were evaluated for germline genetic testing. Patient demographic data and germline genetic testing and recommendation, clinical, treatment, and outcome data were collected and analyzed. RESULTS: Sixty patients were included; 29 (47.5%) were female. The mean age at consultation was 11.0 ± 4.9 years. Diagnoses included cerebral arteriovenous malformations (AVMs) (n = 23), cerebral cavernous malformations (n = 19), non-neurofibromatosis/non-sickle cell moyamoya (n = 8), diffuse cerebral proliferative angiopathy, and megalencephaly-capillary malformation. Of the 56 patients recommended to have genetic testing, 40 completed it. Genetic alterations were found in 13 (23%) patients. Four patients with AVMs had RASA1, GDF2, and ACVRL1 mutations. Four patients with cavernous malformations had Krit1 mutations. One with moyamoya disease had an RNF213 mutation. Three patients with megalencephaly-capillary malformation had PIK3CA mutations, and 1 patient with a cavernous sinus lesion had an MED12 mutation. The majority of AVM patients were treated surgically. Patients with diffuse cerebral proliferative angiopathy were treated medically with sirolimus. At-risk relatives of 3 patients positive for genetic anomalies had also been tested. CONCLUSIONS: This study demonstrates a role for exploring genetic alterations in the identification and treatment of pediatric neurovascular disease pathogenesis. Germline genetic mutations were found in almost one-quarter of the patients screened in this study, results that helped to identify medically targeted treatment modalities for some pediatric neurovascular patients. Insight into the genetic etiology of vascular anomalies may provide broader clinical implications for risk assessment, family screening, follow-up surveillance, and medical management.

The history of the surgical repair of spina bifida.

INTRODUCTION: The history of surgical spina bifida repair has seen many successes and failures. Many early surgeons attempted treatment of open spina bifida defects before a clear understanding of the disease process or pathology had been discovered. CONCLUSIONS: The attempts, while often fruitless, served to better our understanding of the disease and represent stepping-stones to the treatment we successfully use today. The present paper reviews the history of the surgical treatment of myelomeningoceles.

Natural history of posterior fetal cephaloceles and incidence of progressive cephalocele herniation.

OBJECTIVE: In utero repair of fetal posterior cephaloceles (meningocele and encephalocele) is being performed based on the premise that fetal surgery prevents progressive herniation of neural tissue and brain damage during pregnancy. However, the extent to which progressive herniation occurs during pregnancy, specifically from prenatal diagnosis to after delivery, is not well known. The objective of this study was to describe the natural history of patients with fetal cephaloceles focusing on the incidence of progressive herniation. METHODS: The authors conducted a retrospective cohort study of all patients referred to their center for posterior fetal cephalocele between 2006 and 2021. All patients underwent prenatal and postnatal MRI. Progressive herniation (primary outcome) was defined as an increase in the absolute volume of neural tissue within the cephalocele of > 5% or new herniation of a critical structure into the cephalocele. Total brain and cephalocele volumes were calculated to determine herniation progression from prenatal to postnatal MRI. Information on the presence of hydrocephalus, epilepsy, and developmental delay (secondary outcomes) was collected at 1 year of age. RESULTS: Twenty patients met all study criteria. Ten patients (50%; 95% CI 0.27-0.73) demonstrated progressive herniation from prenatal to postnatal MRI. Three patients with progressive herniation were diagnosed with a meningocele prenatally and had an encephalocele postnatally. Two patients without progression had meningocele identified prenatally that regressed and became atretic by birth. Both prenatal hindbrain herniation (p = 0.03) and prenatal microcephaly (p = 0.05) were predictive of progressive herniation. The rates of hydrocephalus (44%), epilepsy (44%), and developmental delay (63%) were not associated with the occurrence of progressive herniation in this study. CONCLUSIONS: In this study, progressive herniation was not a rare event (50%). Fetal hindbrain herniation and fetal microcephaly were associated with the occurrence of progressive herniation. These results support further investigations into why progressive herniation occurs in utero and if progressive cerebral herniation in utero plays a significant role in determining clinical outcome.

Acquisition of temozolomide chemoresistance in gliomas leads to remodeling of mitochondrial electron transport chain.

Temozolomide (TMZ) is an oral alkylating agent used for the treatment of high-grade gliomas. Acquired chemoresistance is a severe limitation to this therapy with more than 90% of recurrent gliomas showing no response to a second cycle of chemotherapy. Efforts to better understand the underlying mechanisms of acquired chemoresistance to TMZ and potential strategies to overcome chemoresistance are, therefore, critically needed. TMZ methylates nuclear DNA and induces cell death; however, the impact on mitochondria DNA (mtDNA) and mitochondrial bioenergetics is not known. Herein, we tested the hypothesis that TMZ-mediated alterations in mtDNA and respiratory function contribute to TMZ-dependent acquired chemoresistance. Using an in vitro model of TMZ-mediated acquired chemoresistance, we report 1) a decrease in mtDNA copy number and the presence of large heteroplasmic mtDNA deletions in TMZ-resistant glioma cells, 2) remodeling of the entire electron transport chain with significant decreases of complexes I and V and increases of complexes II/III and IV, and 3) pharmacologic and genetic manipulation of cytochrome c oxidase, which restores sensitivity to TMZ-dependent apoptosis in resistant glioma cells. Importantly, human primary and recurrent pairs of glioblastoma multiforme (GBM) biopsies as well as primary and TMZ-resistant GBM xenograft lines exhibit similar remodeling of the ETC. Overall these results suggest that TMZ-dependent acquired chemoresistance may be due to a mitochondrial adaptive response to TMZ genotoxic stress with a major contribution from cytochrome c oxidase. Thus, abrogation of this adaptive response may reverse chemoresistance and restore sensitivity to TMZ, providing a strategy for improved therapeutic outcomes in GBM patients.

Review of Tone Management for the Primary Care Provider.

Movement disorders in a pediatric population represent a spectrum of secondary functional deficits affecting ease of care, ambulation, and activities of daily living. Cerebral palsy represents the most common form of movement disorder seen in the pediatric population. Several medical and surgical options exist in the treatment of pediatric spasticity and dystonia, which can have profound effects on the functionality of these patients. Given the complex medical and surgical problems in these patients, children are well served by a multidisciplinary team of practitioners, including physical therapists, physical medicine and rehabilitation physicians, and surgeons.

Intrawound Liposomal Bupivacaine in Pediatric Chiari Decompression: A Retrospective Study.

Intrawound liposomal bupivacaine is a long-acting local anesthetic used to decrease postoperative pain in various procedures. Although it is used in posterior cervical and suboccipital approaches in the adult population, it is currently off-label for pediatrics. This quality improvement (QI) project examines intrawound liposomal bupivacaine for pediatric Chiari decompression and evaluates its role in postoperative opioid consumption. METHODS: We retrospectively analyzed all patients 0-18 years old of age who underwent Chiari decompression from January 2017 to July 2019 at our tertiary care hospital. Demographic and clinical data regarding postoperative opioid use, subjective and objective pain control, length of stay, discharge medications, and comorbid conditions were collected. RESULTS: We included 30 patients in this study: 19 females and 11 males. Of these, 6 received an intrawound injection of liposomal bupivacaine. PATIENTS: treated with liposomal bupivacaine require fewer opioids while admitted. There was no apparent difference in pain control immediately postoperatively, pain control at clinical follow-up, or inpatient length of stay between each group. Patients who received liposomal bupivacaine did not require opioid analgesics at the time of discharge from the hospital. CONCLUSION: The use of intrawound liposomal bupivacaine may decrease inpatient and outpatient postoperative opioid consumption amongst pediatric patients following Chiari decompression while providing adequate pain control. We investigate liposomal bupivacaine perioperative blockade in this QI project as a viable option for opioid-sparing pain control in the postoperative setting for the pediatric population. Future investigation via clinical trials and more extensive prospective studies may glean further insights into efficacy.

Pediatric neurosurgery at Texas Children's Hospital: the legacy of Dr. William R. Cheek.

Texas Children's Hospital opened its doors in 1954, and since that time the institution has remained dedicated to a three-part mission: patient care, education, and research. Dr. William R. Cheek developed an early interest in pediatric neurosurgery, which led to his efforts in building and developing a service at Texas Children's Hospital at a time when the field was just emerging. His work with other early pioneers in the field led to the establishment of organized societies, educational texts, and governing bodies that have led to significant advances in the field over the past 50 years.

Functional outcomes at 2 years of age following treatment for posthemorrhagic hydrocephalus of prematurity: what do we know at the time of consult?

OBJECTIVE: Posthemorrhagic hydrocephalus of prematurity remains a significant problem in preterm infants. In the literature, there is a scarcity of data on the early disease process, when neurosurgeons are typically consulted for recommendations on treatment. Here, the authors sought to evaluate functional outcomes in premature infants at 2 years of age following treatment for posthemorrhagic hydrocephalus. Their goal was to determine the relationship between factors identifiable at the time of the initial neurosurgical consult and outcomes of patients when they are 2 years of age. METHODS: The authors performed a retrospective chart review of premature infants treated for intraventricular hemorrhage (IVH) of prematurity (grade III and IV) between 2003 and 2014. Information from three time points (birth, first neurosurgical consult, and 2 years of age) was collected on each patient. Logistic regression analysis was performed to determine the association between variables known at the time of the first neurosurgical consult and each of the outcome variables. RESULTS: One hundred thirty patients were selected for analysis. At 2 years of age, 16% of the patients had died, 88% had cerebral palsy/developmental delay (CP), 48% were nonverbal, 55% were nonambulatory, 33% had epilepsy, and 41% had visual impairment. In the logistic regression analysis, IVH grade was an independent predictor of CP (p = 0.004), which had an estimated probability of occurrence of 74% in grade III and 96% in grade IV. Sepsis at or before the time of consult was an independent predictor of visual impairment (p = 0.024), which had an estimated probability of 58%. IVH grade was an independent predictor of epilepsy (p = 0.026), which had an estimated probability of 18% in grade III and 43% in grade IV. The IVH grade was also an independent predictor of verbal function (p = 0.007), which had an estimated probability of 68% in grade III versus 41% in grade IV. A higher weeks gestational age (WGA) at birth was an independent predictor of the ability to ambulate (p = 0.0014), which had an estimated probability of 15% at 22 WGA and up to 98% at 36 WGA. The need for oscillating ventilation at consult was an independent predictor of death before 2 years of age (p = 0.001), which had an estimated probability of 42% in patients needing oscillating ventilation versus 13% in those who did not. CONCLUSIONS: IVH grade was consistently an independent predictor of functional outcomes at 2 years. Gestational age at birth, sepsis, and the need for oscillating ventilation may also predict worse functional outcomes.

The Chiari I malformation.

As with many pathologies, the course of our understanding of the Chiari I malformation (CIM) has developed extensively over time. The early descriptions of the Chiari malformations by Hans Chiari in 1891 opened the door for future classification and research on this topic. However, even over a long timeframe, our understanding of the pathophysiology and, more importantly, treatment, remained in its infancy. As recently as the 1970s, CIM was not discussed in popular neurology textbooks. Syringomyelia is listed as a degenerative disorder with no satisfactory treatment. Radiation therapy was considered an option in treatment, and surgery was thought to play no role. During the last 40 years, equivalent to the duration of a neurosurgical career, our understanding of the pathophysiology and natural history of CIM, coupled with modern MRI, has improved the treatment paradigm for this patient population. More importantly, it has given us evidence confirming that CIM is a disorder responsive to surgical intervention, giving patients once thought to be destined for lifelong disability a comparatively normal life after treatment. The purpose of this article is to offer a review of CIM and its important associated entities. The authors will discuss the evolution in understanding of the Chiari malformation and, importantly, distinguish between symptomatic CIM and asymptomatic tonsillar ectopia, based on imaging and presenting symptomatology. They will discuss techniques for surgical intervention, expected outcomes, and complications after surgery. Proper patient selection for surgery based on appropriate symptomatology is tantamount to achieving good surgical outcomes in this population, separating those who can be helped by surgery from those who are unlikely to improve. While our knowledge of the Chiari malformations continues to improve through the efforts of clinical and basic science researchers, surgeons, and patients, our current understanding of these entities represents a monumental improvement in patient care over a relatively short time period.

Venous thromboembolism following inpatient pediatric surgery: Analysis of 153,220 patients.

PURPOSE: To evaluate venous thromboembolism (VTE) rates and risk factors following inpatient pediatric surgery. METHODS: 153,220 inpatient pediatric surgical patients were selected from the 2012-2015 NSQIP-P database. Demographic and perioperative variables were documented. Primary outcome was VTE requiring treatment within 30 postoperative days. Secondary outcomes included length of stay (LOS) and 30-day mortality. Prediction models were generated using logistic regression. Mortality and time to VTE were assessed using Kaplan-Meier survival analysis. RESULTS: 305 patients (0.20%) developed 296 venous thromboses and 12 pulmonary emboli (3 cooccurrences). Median time to VTE was 9 days. Most VTEs (81%) occurred predischarge. Subspecialties with highest VTE rates were cardiothoracic (0.72%) and general surgery (0.28%). No differences were seen for elective vs. urgent/emergent procedures (p = 0.106). All-cause mortality VTE patients was 1.2% vs. 0.2% in patients without VTE (p < 0.001). After stratifying by American Society of Anesthesiologists (ASA) class, no mortality differences remained when ASA < 3. Preoperative, postoperative, and total LOSs were longer for patients with VTE (p < 0.001 for each). ASA ≥ 3, preoperative sepsis, ventilator dependence, enteral/parenteral feeding, steroid use, preoperative blood transfusion, gastrointestinal disease, hematologic disorders, operative time, and age were independent predictors (C-statistic = 0.83). CONCLUSIONS: Pediatric postsurgical patients have unique risk factors for developing VTE. LEVEL OF EVIDENCE: Level II.

Association between preoperative activity level and functional outcome at 12 months following surgical decompression for lumbar spinal stenosis.

OBJECTIVE: This study defines the association of preoperative physical activity level with functional outcomes at 3 and 12 months following surgical decompression for lumbar spinal stenosis. METHODS: Data were collected as a prospective observational registry at a single institution from 2012 through 2015, and then analyzed with a retrospective cohort design. Patients who were able to participate in activities outside the home preoperatively were compared to patients who did not participate in such activities, with respect to 3-month and 12-month functional outcomes postintervention, adjusted for relevant confounders. RESULTS: Ninety-nine patients were included. At baseline, sedentary/inactive patients (n = 55) reported greater back pain, lower quality of life, and higher disability than similarly treated patients who were active preoperatively. Both cohorts experienced significant improvement from baseline in back pain, leg pain, disability, and quality of life at both 3 and 12 months after lumbar decompression surgery. At 3 months postintervention, sedentary/inactive patients reported more leg pain and worse disability than patients who performed activities outside the home preoperatively. However, at 12 months postintervention, there were no statistically significant differences between the two cohorts in back pain, leg pain, quality of life, or disability. Multivariate analysis revealed that sedentary/inactive patients had improved disability and higher quality of life after surgery compared to baseline. Active patients experienced greater overall improvement in disability compared to inactive patients. CONCLUSIONS: Sedentary/inactive patients have a more protracted recovery after lumbar decompression surgery for spinal stenosis, but at 12 months postintervention can expect to reach similar long-term outcomes as patients who are active/perform activities outside the home preoperatively.