Impact of ventricle size on neuropsychological outcomes in treated pediatric hydrocephalus: an HCRN prospective cohort study

OBJECTIVE

In pediatric hydrocephalus, shunts tend to result in smaller postoperative ventricles compared with those following an endoscopic third ventriculostomy (ETV). The impact of the final treated ventricle size on neuropsychological and quality-of-life outcomes is currently undetermined. Therefore, the authors sought to ascertain whether treated ventricle size is associated with neurocognitive and academic outcomes postoperatively.

METHODS

This prospective cohort study included children aged 5 years and older at the first diagnosis of hydrocephalus at 8 Hydrocephalus Clinical Research Network sites from 2011 to 2015. The treated ventricle size, as measured by the frontal and occipital horn ratio (FOR), was compared with 25 neuropsychological tests 6 months postoperatively after adjusting for age, hydrocephalus etiology, and treatment type (ETV vs shunt). Pre- and posttreatment grade point average (GPA), quality-of-life measures (Hydrocephalus Outcome Questionnaire [HOQ]), and a truncated preoperative neuropsychological battery were also compared with the FOR.

RESULTS

Overall, 60 children were included with a mean age of 10.8 years; 17% had ≥ 1 comorbidity. Etiologies for hydrocephalus were midbrain lesions (37%), aqueductal stenosis (22%), posterior fossa tumors (13%), and supratentorial tumors (12%). ETV (78%) was more commonly used than shunting (22%). Of the 25 neuropsychological tests, including full-scale IQ (q = 0.77), 23 tests showed no univariable association with postoperative ventricle size. Verbal learning delayed recall (p = 0.006, q = 0.118) and visual spatial judgment (p = 0.006, q = 0.118) were negatively associated with larger ventricles and remained significant after multivariate adjustment for age, etiology, and procedure type. However, neither delayed verbal learning (p = 0.40) nor visual spatial judgment (p = 0.22) was associated with ventricle size change with surgery. No associations were found between postoperative ventricle size and either GPA or the HOQ.

CONCLUSIONS

Minimal associations were found between the treated ventricle size and neuropsychological, academic, or quality-of-life outcomes for pediatric patients in this comprehensive, multicenter study that encompassed heterogeneous hydrocephalus etiologies.

Finding the Needle in the Hay Stack: Population-based Study of Prediagnostic Symptomatic Interval in Children With CNS Tumors

Central nervous system (CNS) tumors in children are a devastating diagnosis and delay in diagnosis is well documented in the literature. The aim of this study was to document and characterize time to diagnosis of CNS tumors among children 0 to 17 years of age in a pediatric center. A retrospective chart review was conducted of medical records of children with CNS tumors from 2000 to 2016 in British Columbia, Canada and 148 reports were available for review. Average age at diagnosis was 87.8 months (SD=59.7; median=72). One third (30%) were diagnosed after a single visit to a health care provider and 11 (7.7%) after more than 4 visits. Median time to diagnosis (prediagnostic symptomatic interval [PSI]) was 62 days (average 197±341 d; range, 0 to 2047 d). Longest period was time from first symptom to first health care provider visit (PSI1, median 37 d). Tumors in the posterior fossa and symptoms of ataxia or paresis were associated with a significantly shorter PSI. CNS tumors in children continue to pose a diagnostic challenge with variability in time to diagnosis. Our population-based study suggests variability in time to diagnosis with a need for education of families to identify symptoms associated with CNS tumors.

Predictors of success for combined endoscopic third ventriculostomy and choroid plexus cauterization in a North American setting: a Hydrocephalus Clinical Research Network study

OBJECTIVE

Endoscopic third ventriculostomy combined with choroid plexus cauterization (ETV+CPC) has been adopted by many pediatric neurosurgeons as an alternative to placing shunts in infants with hydrocephalus. However, reported success rates have been highly variable, which may be secondary to patient selection, operative technique, and/or surgeon training. The objective of this prospective multicenter cohort study was to identify independent patient selection, operative technique, or surgical training predictors of ETV+CPC success in infants.

METHODS

This was a prospective cohort study nested within the Hydrocephalus Clinical Research Network's (HCRN) Core Data Project (registry). All infants under the age of 2 years who underwent a first ETV+CPC between June 2006 and March 2015 from 8 HCRN centers were included. Each patient had a minimum of 6 months of follow-up unless censored by an ETV+CPC failure. Patient and operative risk factors of failure were examined, as well as formal ETV+CPC training, which was defined as traveling to and working with the experienced surgeons at CURE Children's Hospital of Uganda. ETV+CPC failure was defined as the need for repeat ETV, shunting, or death.

RESULTS

The study contained 191 patients with a primary ETV+CPC conducted by 17 pediatric neurosurgeons within the HCRN. Infants under 6 months corrected age at the time of ETV+CPC represented 79% of the cohort. Myelomeningocele (26%), intraventricular hemorrhage associated with prematurity (24%), and aqueductal stenosis (17%) were the most common etiologies. A total of 115 (60%) of the ETV+CPCs were conducted by surgeons after formal training. Overall, ETV+CPC was successful in 48%, 46%, and 45% of infants at 6 months, 1 year, and 18 months, respectively. Young age (< 1 month) (adjusted hazard ratio [aHR] 1.9, 95% CI 1.0-3.6) and an etiology of post-intraventricular hemorrhage secondary to prematurity (aHR 2.0, 95% CI 1.1-3.6) were the only two independent predictors of ETV+CPC failure. Specific subgroups of ages within etiology categories were identified as having higher ETV+CPC success rates. Although training led to more frequent use of the flexible scope (p < 0.001) and higher rates of complete (> 90%) CPC (p < 0.001), training itself was not independently associated (aHR 1.1, 95% CI 0.7-1.8; p = 0.63) with ETV+CPC success.

CONCLUSIONS

This is the largest prospective multicenter North American study to date examining ETV+CPC. Formal ETV+CPC training was not found to be associated with improved procedure outcomes. Specific subgroups of ages within specific hydrocephalus etiologies were identified that may preferentially benefit from ETV+CPC.

Examining the need for routine intensive care admission after surgical repair of nonsyndromic craniosynostosis: a preliminary analysis

OBJECTIVEAt British Columbia Children's Hospital (BCCH), pediatric patients with nonsyndromic craniosynostosis are admitted directly to a standard surgical ward after craniosynostosis surgery. This study's purpose was to investigate the safety of direct ward admission and to examine the rate at which patients were transferred to the intensive care unit (ICU), the cause for the transfer, and any patient characteristics that indicate higher risk for ICU care.METHODSThe authors retrospectively reviewed medical records of pediatric patients who underwent single-suture or nonsyndromic craniosynostosis repair from 2011 to 2016 at BCCH. Destination of admission from the operating room (i.e., ward or ICU) and transfer to the ICU from the ward were evaluated. Patient characteristics and operative factors were recorded and analyzed.RESULTSOne hundred fourteen patients underwent surgery for single-suture or nonsyndromic craniosynostosis. Eighty surgeries were open procedures (cranial vault reconstruction, frontoorbital advancement, extended-strip craniectomy) and 34 were minimally invasive endoscope-assisted craniectomy (EAC). Sutures affected were sagittal in 66 cases (32 open, 34 EAC), coronal in 20 (15 unilateral, 5 bilateral), metopic in 23, and multisuture in 5. Only 5 patients who underwent open procedures (6%) were initially admitted to the ICU from the operating room; the reasons for direct admission were as follows: the suggestion of preoperative elevated intracranial pressure, pain control, older-age patients with large reconstruction sites, or a significant medical comorbidity. Overall, of the 107 patients admitted directly to the ward (75 who underwent an open surgery, 32 who underwent an EAC), none required ICU transfer.CONCLUSIONSOverall, the findings of this study suggest that patients with nonsyndromic craniosynostosis can be managed safely on the ward and do not require postoperative ICU admission. This could potentially increase cost savings and ICU resource utilization.

Choosing Wisely Canada: Pediatric Neurosurgery Recommendations

OBJECTIVES

Choosing Wisely Canada is an evidence-based, patient-focused, physician-led campaign to improve the delivery of medical care in Canada. The goal of this study was to produce Canadian recommendations for physicians treating patients with selected paediatric neurosurgery issues.

METHODS

Paediatric neurosurgeons practicing in Canada were invited to participate. Suggestions were obtained using an anonymous questionnaire, and then ranked anonymously by the participating surgeons. Suggestions that received consensus from participants were discussed at the 2016 annual Canadian Pediatric Neurosurgery Study Group meeting. Suggestions that were not evidence based, or that would not have a substantive population impact were eliminated. All remaining suggestions were anonymously ranked by the group and the top five recommendations were submitted to Choosing Wisely Canada.

RESULTS

The final five recommendations include: 1) don't order a computed tomography scan to investigate macrocephaly (order an ultrasound or magnetic resonance imaging scan); 2) don't image a midline dimple related to the coccyx in an asymptomatic infant or child; 3) don't use computed tomography scans for routine imaging of children with hydrocephalus. Fast sequence nonsedated magnetic resonance imaging scans or ultrasounds provide adequate information to assess patients without exposing them to radiation or an anesthetic; 4) don't recommend helmets for mild to severe positional flattening; 5) don't do routine surveillance imaging for incidentally discovered Chiari I malformation.

CONCLUSIONS

Five Choosing Wisely Canada recommendations were produced to support care of patients with paediatric neurosurgical issues. While these recommendations will apply to the majority of children with the involved conditions, occasionally, deviation from these recommendations may be clinically indicated.

Reinfection after treatment of first cerebrospinal fluid shunt infection: a prospective observational cohort study

OBJECTIVE CSF shunt infection requires both surgical and antibiotic treatment. Surgical treatment includes either total shunt removal with external ventricular drain (EVD) placement followed by new shunt insertion, or distal shunt externalization followed by new shunt insertion once the CSF is sterile. Antibiotic treatment includes the administration of intravenous antibiotics. The Hydrocephalus Clinical Research Network (HCRN) registry provides a unique opportunity to understand reinfection following treatment for CSF shunt infection. This study examines the association of surgical and antibiotic decisions in the treatment of first CSF shunt infection with reinfection. METHODS A prospective cohort study of children undergoing treatment for first CSF infection at 7 HCRN hospitals from April 2008 to December 2012 was performed. The HCRN consensus definition was used to define CSF shunt infection and reinfection. The key surgical predictor variable was surgical approach to treatment for CSF shunt infection, and the key antibiotic treatment predictor variable was intravenous antibiotic selection and duration. Cox proportional hazards models were constructed to address the time-varying nature of the characteristics associated with shunt surgeries. RESULTS Of 233 children in the HCRN registry with an initial CSF shunt infection during the study period, 38 patients (16%) developed reinfection over a median time of 44 days (interquartile range [IQR] 19-437). The majority of initial CSF shunt infections were treated with total shunt removal and EVD placement (175 patients; 75%). The median time between infection surgeries was 15 days (IQR 10-22). For the subset of 172 infections diagnosed by CSF culture, the mean ± SD duration of antibiotic treatment was 18.7 ± 12.8 days. In all Cox proportional hazards models, neither surgical approach to infection treatment nor overall intravenous antibiotic duration was independently associated with reinfection. The only treatment decision independently associated with decreased infection risk was the use of rifampin. While this finding did not achieve statistical significance, in all 5 Cox proportional hazards models both surgical approach (other than total shunt removal at initial CSF shunt infection) and nonventriculoperitoneal shunt location were consistently associated with a higher hazard of reinfection, while the use of ultrasound was consistently associated with a lower hazard of reinfection. CONCLUSIONS Neither surgical approach to treatment nor antibiotic duration was associated with reinfection risk. While these findings did not achieve statistical significance, surgical approach other than total removal at initial CSF shunt infection was consistently associated with a higher hazard of reinfection in this study and suggests the feasibility of controlling and standardizing the surgical approach (shunt removal with EVD placement). Considerably more variation and equipoise exists in the duration and selection of intravenous antibiotic treatment. Further consideration should be given to the use of rifampin in the treatment of CSF shunt infection. High-quality studies of the optimal duration of antibiotic treatment are critical to the creation of evidence-based guidelines for CSF shunt infection treatment.

Endoscopic third ventriculostomy and choroid plexus cauterization in infant hydrocephalus: a prospective study by the Hydrocephalus Clinical Research Network

OBJECTIVE High-quality data comparing endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) to shunt and ETV alone in North America are greatly lacking. To address this, the Hydrocephalus Clinical Research Network (HCRN) conducted a prospective study of ETV+CPC in infants. Here, these prospective data are presented and compared to prospectively collected data from a historical cohort of infants treated with shunt or ETV alone. METHODS From June 2014 to September 2015, infants (corrected age ≤ 24 months) requiring treatment for hydrocephalus with anatomy suitable for ETV+CPC were entered into a prospective study at 9 HCRN centers. The rate of procedural failure (i.e., the need for repeat hydrocephalus surgery, hydrocephalus-related death, or major postoperative neurological deficit) was determined. These data were compared with a cohort of similar infants who were treated with either a shunt (n = 969) or ETV alone (n = 74) by creating matched pairs on the basis of age and etiology. These data were obtained from the existing prospective HCRN Core Data Project. All patients were observed for at least 6 months. RESULTS A total of 118 infants underwent ETV+CPC (median corrected age 1.3 months; common etiologies including myelomeningocele [30.5%], intraventricular hemorrhage of prematurity [22.9%], and aqueductal stenosis [21.2%]). The 6-month success rate was 36%. The most common complications included seizures (5.1%) and CSF leak (3.4%). Important predictors of treatment success in the survival regression model included older age (p = 0.002), smaller preoperative ventricle size (p = 0.009), and greater degree of CPC (p = 0.02). The matching algorithm resulted in 112 matched pairs for ETV+CPC versus shunt alone and 34 matched pairs for ETV+CPC versus ETV alone. ETV+CPC was found to have significantly higher failure rate than shunt placement (p < 0.001). Although ETV+CPC had a similar failure rate compared with ETV alone (p = 0.73), the matched pairs included mostly infants with aqueductal stenosis and miscellaneous other etiologies but very few patients with intraventricular hemorrhage of prematurity. CONCLUSIONS Within a large and broad cohort of North American infants, our data show that overall ETV+CPC appears to have a higher failure rate than shunt alone. Although the ETV+CPC results were similar to ETV alone, this comparison was limited by the small sample size and skewed etiological distribution. Within the ETV+CPC group, greater extent of CPC was associated with treatment success, thereby suggesting that there are subgroups who might benefit from the addition of CPC. Further work will focus on identifying these subgroups.

Ventricular catheter entry site and not catheter tip location predicts shunt survival: a secondary analysis of 3 large pediatric hydrocephalus studies

OBJECTIVE Accurate placement of ventricular catheters may result in prolonged shunt survival, but the best target for the hole-bearing segment of the catheter has not been rigorously defined. The goal of the study was to define a target within the ventricle with the lowest risk of shunt failure. METHODS Five catheter placement variables (ventricular catheter tip location, ventricular catheter tip environment, relationship to choroid plexus, catheter tip holes within ventricle, and crosses midline) were defined, assessed for interobserver agreement, and evaluated for their effect on shunt survival in univariate and multivariate analyses. De-identified subjects from the Shunt Design Trial, the Endoscopic Shunt Insertion Trial, and a Hydrocephalus Clinical Research Network study on ultrasound-guided catheter placement were combined (n = 858 subjects, all first-time shunt insertions, all patients < 18 years old). The first postoperative brain imaging study was used to determine ventricular catheter placement for each of the catheter placement variables. RESULTS Ventricular catheter tip location, environment, catheter tip holes within the ventricle, and crosses midline all achieved sufficient interobserver agreement (κ > 0.60). In the univariate survival analysis, however, only ventricular catheter tip location was useful in distinguishing a target within the ventricle with a survival advantage (frontal horn; log-rank, p = 0.0015). None of the other catheter placement variables yielded a significant survival advantage unless they were compared with catheter tips completely not in the ventricle. Cox regression analysis was performed, examining ventricular catheter tip location with age, etiology, surgeon, decade of surgery, and catheter entry site (anterior vs posterior). Only age (p < 0.001) and entry site (p = 0.005) were associated with shunt survival; ventricular catheter tip location was not (p = 0.37). Anterior entry site lowered the risk of shunt failure compared with posterior entry site by approximately one-third (HR 0.65, 95% CI 0.51-0.83). CONCLUSIONS This analysis failed to identify an ideal target within the ventricle for the ventricular catheter tip. Unexpectedly, the choice of an anterior versus posterior catheter entry site was more important in determining shunt survival than the location of the ventricular catheter tip within the ventricle. Entry site may represent a modifiable risk factor for shunt failure, but, due to inherent limitations in study design and previous clinical research on entry site, a randomized controlled trial is necessary before treatment recommendations can be made.

Endoscopic third ventriculostomy in children: prospective, multicenter results from the Hydrocephalus Clinical Research Network

OBJECTIVE Endoscopic third ventriculostomy (ETV) is now established as a viable treatment option for a subgroup of children with hydrocephalus. Here, the authors report prospective, multicenter results from the Hydrocephalus Clinical Research Network (HCRN) to provide the most accurate determination of morbidity, complication incidence, and efficacy of ETV in children and to determine if intraoperative predictors of ETV success add substantially to preoperative predictors. METHODS All children undergoing a first ETV (without choroid plexus cauterization) at 1 of 7 HCRN centers up to June 2013 were included in the study and followed up for a minimum of 18 months. Data, including detailed intraoperative data, were prospectively collected as part of the HCRN's Core Data Project and included details of patient characteristics, ETV failure (need for repeat hydrocephalus surgery), and, in a subset of patients, postoperative complications up to the time of discharge. RESULTS Three hundred thirty-six eligible children underwent initial ETV, 18.8% of whom had undergone shunt placement prior to the ETV. The median age at ETV was 6.9 years (IQR 1.7-12.6), with 15.2% of the study cohort younger than 12 months of age. The most common etiologies were aqueductal stenosis (24.8%) and midbrain or tectal lesions (21.2%). Visible forniceal injury (16.6%) was more common than previously reported, whereas severe bleeding (1.8%), thalamic contusion (1.8%), venous injury (1.5%), hypothalamic contusion (1.5%), and major arterial injury (0.3%) were rare. The most common postoperative complications were CSF leak (4.4%), hyponatremia (3.9%), and pseudomeningocele (3.9%). New neurological deficit occurred in 1.5% cases, with 0.5% being permanent. One hundred forty-one patients had documented failure of their ETV requiring repeat hydrocephalus surgery during follow-up, 117 of them during the first 6 months postprocedure. Kaplan-Meier rates of 30-day, 90-day, 6-month, 1-year, and 2-year failure-free survival were 73.7%, 66.7%, 64.8%, 61.7%, and 57.8%, respectively. According to multivariate modeling, the preoperative ETV Success Score (ETVSS) was associated with ETV success (p < 0.001), as was the intraoperative ability to visualize a "naked" basilar artery (p = 0.023). CONCLUSIONS The authors' documented experience represents the most detailed account of ETV results in North America and provides the most accurate picture to date of ETV success and complications, based on contemporaneously collected prospective data. Serious complications with ETV are low. In addition to the ETVSS, visualization of a naked basilar artery is predictive of ETV success.

Radiographic predictors of deterioration in patients with lumbosacral lipomas

OBJECTIVE Although patients with lumbosacral lipomas may be asymptomatic at presentation, most develop neurological symptoms over time. Given the challenges in examining infants, the authors sought to determine whether MRI would be helpful in identifying patients who are more likely to deteriorate early in life and who would potentially benefit from early surgical intervention. METHODS A retrospective review of all patients with lumbosacral lipomas who were seen at the authors' institution between 1997 and 2013 and who were managed without prophylactic surgery was performed. The clinical history and imaging results for each patient were reviewed in detail and then correlated to the pattern of and age at clinical deterioration. RESULTS Twenty-four patients were identified. Nine worsened within the first 18 months of life (early deterioration), and 15 patients deteriorated or remained stable after 30 months (late deterioration/stable). No patients worsened between 18 and 30 months of age. Patients who deteriorated early were more likely to have large intradural lipomas that filled the canal, increased during the 1st year of life, and compressed neurological structures. Some had a syrinx extending above the neural-lipoma interface. Syrinxes in patients with early deterioration were large and expanded in infancy. Patients with early deterioration had motor deficits at the time of deterioration, whereas patients with late deterioration developed mixed urological and motor dysfunction. CONCLUSIONS Patients with large lipomas displacing the cord and an enlarging syrinx have a propensity for early clinical deterioration. Given this, their families may be counseled that 1) the risk of deterioration in infancy may be higher than in infants without these features, and 2) they require more diligent observation. Intervention before deterioration in these infants should also be considered. Patients without these features may be safely observed to a lesser extent.

The natural history and management of patients with congenital deficits associated with lumbosacral lipomas

INTRODUCTION

Many patients with lumbosacral lipoma are asymptomatic; however, a significant proportion will have neurological deficits present at birth. Implication of these deficits with respect to natural history and management are not well understood.

METHODS

A retrospective review of all infants with lumbosacral lipoma seen at BCCH between 1997 and 2013 was carried out. The study population was stratified on the presence of a congenital, non-progressive deficit and subdivided on treatment approach. The subsequent developments of deficits resulting in untethering procedures were recorded.

RESULTS

Of the 44 infants in this study, 24 patients had no neurologic deficit while 20 patients had a fixed, non-progressive deficit evident at birth. Ten of 24 patients without a neurological deficit at birth underwent a prophylactic untethering with 3 eventually requiring repeat untethering after, on average, 62.7 months. Eleven of 14 asymptomatic, monitored patients required untethering for clinical deterioration. Two required a second untethering procedure after 48.7 months. Ten of 20 infants with congenital deficits present at birth underwent prophylactic untethering, and 4 required further surgery after 124 months. Ten patients underwent observation with 8 eventually requiring surgery. Two required repeat untethered after 154 months. The complication rates and operative burden for patients are similar whether prophylactic or delayed surgery is performed.

CONCLUSION

The presence of congenital neurologic deficit does not affect the likelihood of deterioration in patients managed expectantly; prophylactic detethering of these patients did not prevent delayed neurologic deterioration. Comparing the need for repeat surgery in prophylactically untethered patients with initial untethering of patients operated upon at the time of deterioration, prophylactic untethering may confer a benefit with respect to subsequent symptomatic tethering if complication rates are low. However, in a setting with multidisciplinary follow-up, a period of observation for patients and intervention when patients become symptomatic is an acceptable approach for patients with or without congenital deficits.

A new Hydrocephalus Clinical Research Network protocol to reduce cerebrospinal fluid shunt infection

OBJECT In a previous report by the same research group (Kestle et al., 2011), compliance with an 11-step protocol was shown to reduce CSF shunt infection at Hydrocephalus Clinical Research Network (HCRN) centers (from 8.7% to 5.7%). Antibiotic-impregnated catheters (AICs) were not part of the protocol but were used off protocol by some surgeons. The authors therefore began using a new protocol that included AICs in an effort to reduce the infection rate further. METHODS The new protocol was implemented at HCRN centers on January 1, 2012, for all shunt procedures (excluding external ventricular drains [EVDs], ventricular reservoirs, and subgaleal shunts). Procedures performed up to September 30, 2013, were included (21 months). Compliance with the protocol and outcome events up to March 30, 2014, were recorded. The definition of infection was unchanged from the authors' previous report. RESULTS A total of 1935 procedures were performed on 1670 patients at 8 HCRN centers. The overall infection rate was 6.0% (95% CI 5.1%-7.2%). Procedure-specific infection rates varied (insertion 5.0%, revision 5.4%, insertion after EVD 8.3%, and insertion after treatment of infection 12.6%). Full compliance with the protocol occurred in 77% of procedures. The infection rate was 5.0% after compliant procedures and 8.7% after noncompliant procedures (p = 0.005). The infection rate when using this new protocol (6.0%, 95% CI 5.1%-7.2%) was similar to the infection rate observed using the authors' old protocol (5.7%, 95% CI 4.6%-7.0%). CONCLUSIONS CSF shunt procedures performed in compliance with a new infection prevention protocol at HCRN centers had a lower infection rate than noncompliant procedures. Implementation of the new protocol (including AICs) was associated with a 6.0% infection rate, similar to the infection rate of 5.7% from the authors' previously reported protocol. Based on the current data, the role of AICs compared with other infection prevention measures is unclear.

Preoperative ultrasound localization of the lambda in patients with scaphocephaly: a technical note for minimally invasive craniectomy

Sagittal craniosynostosis, the most common single suture craniosynostosis, is treated by numerous surgical techniques. Minimally invasive endoscopy-assisted procedures with postoperative helmeting are being used with reports of good cosmetic outcomes with decreased morbidity, shortened hospital stay, and less blood loss and transfusion. This procedure uses small skin incisions, which must be properly placed to provide safe access to the posterior sagittal and lambdoid sutures. However, the lambda is often hard to palpate through the skin due to the abnormal head shape. The authors describe their experience with the use of intraoperative, preincision ultrasound localization of the lambda in patients with scaphocephaly undergoing a minimally invasive procedure. This simple technique can also be applied to other operations where proper identification of the cranial sutures is necessary.

Growing teratoma syndrome in intracranial non-germinomatous germ cell tumors (iNGGCTs): a risk for secondary malignant transformation—a report of two cases

PURPOSE

About 5% of pediatric intracranial germ cell tumors and 20% of non-germinomatous germ cell tumors (NGGCT) progress to growing teratoma syndrome (GTS) following chemoradiotherapy. The growing teratoma is thought to arise from the chemotherapy-resistant, teratomatous portion of a germ cell tumor and is commonly benign but may undergo malignant transformation.

METHODS

Two pediatric patients whose intracranial NGGCTs progressed to growing teratomas during chemotherapy and later transformed to secondary malignant tumors after partial resection and radiation therapy (RT).

RESULTS

Both tumors were diagnosed by MRI scans and elevated serum and CSF markers. Following normalization of tumor markers with chemotherapy and initial decrease in tumor volume, subsequent imaging showed regrowth during chemotherapy with pathology revealing benign teratoma. RT was administered. Several years following this treatment, further growth was seen with pathology indicating malignant carcinoma in one patient and malignant rhabdomyosarcoma in the other. The patient with carcinoma received palliative care while the patient with the sarcoma received further resection, intensive chemotherapy, and an autologous stem cell transplant and is currently in remission, 36 months since malignant transformation.

CONCLUSION

Malignant transformation of presumed residual teratoma has been seldom reported. Treatment of NGGCT involves platinum-based chemotherapy with craniospinal RT and boost to the primary site, with cure rates of around 80%. Teratomas are characteristically chemotherapy and RT resistant and are treated surgically. In the event that residual or growing teratoma is suspected, a complete resection should be considered early in the management as there is a risk of malignant transformation of residual teratoma.

What would I want for my surgery?

If you were to have an operation tomorrow, would you want your surgical team members to feel comfortable speaking up, to defy hierarchy, to interact with each other just as well as they perform technical aspects of the procedure? Would you want to feel like part of the team? Your answers to these admittedly leading questions are based on the culture of the surgical team and the interdependence of team members and are at the heart of a current debate around the surgical checklist's effectiveness. In British Columbia (BC), many individuals responded to the paper by Urbach et al. (2014) that described the minimal impact on patient mortality after implementation of the surgical safety checklist in Ontario. They wrote to the Surgical Quality Action Network (SQAN) to express their perspectives, and interestingly, some refuted and others supported the conclusions. Given the strong reaction this study created in the surgical community, a number of key stakeholders have prepared a response in order to provide another perspective to the article and emphasize the checklist's value for improving the culture of surgical teams.

Does optic nerve sheath diameter on MRI decrease with clinically improved pediatric hydrocephalus?

INTRODUCTION

Serial change in ventricular size is recognized as an imperfect indicator of ongoing hydrocephalus in children. Potentially, other radiographic features may be useful in determining the success of hydrocephalus interventions. In this study, optic nerve sheath diameter (ONSD), optic nerve tortuosity, and optic disk bulging were assessed as indicators of hydrocephalus control in children who underwent endoscopic third ventriculostomy (ETV) or posterior fossa tumor resection.

METHODS

Sixteen children underwent ETV or tumor resection for treatment of hydrocephalus. T2-weighted axial magnetic resonance images of the orbit were obtained, and the ONSD was measured posterior to the optic globe, pre- and post-intervention. Evidence of optic disk bulging and optic nerve tortuosity was also assessed. Ventricular size was estimated using the frontal and occipital horn ratio (FOR).

RESULTS

There was a significant reduction in the ONSD post-ETV (n = 9) and after tumor resection (n = 7). Average preoperative ONSD was 6.21 versus 5.71 mm postoperatively (p = 0.0017).There was also an 88% (p = 0.011) and 60% (p = 0.23) reduction in optic disk bulging and tortuosity, respectively. The FOR normalized in the tumor resection group but not the ETV group. After intervention, all patients showed improvement in signs and symptoms of hydrocephalus.

CONCLUSION

In our study population, ONSD decreased in response to measures to reduce hydrocephalus. Optic disk bulging also appears to resolve. Serial reduction in ONSD, and optic disk bulging may be indicators of improved hydrocephalus following pediatric neurosurgical interventions.

Consensus definitions of complications for accurate recording and comparisons of surgical outcomes in pediatric neurosurgery

OBJECT

Monitoring and recording of complications in pediatric neurosurgery are important for quality assurance and in particular for improving outcomes. Lack of accurate or mutually agreed upon definitions hampers this process and makes comparisons between centers, which is an important method to improve outcomes, difficult. Therefore, the Canadian Pediatric Neurosurgery Study Group created definitions of complications in pediatric neurosurgery with consensus among 13 Canadian pediatric neurosurgical centers.

METHODS

Definitions of complications were extracted from randomized trials, prospective data collection studies, and the medical literature. The definitions were presented at an annual meeting and were subsequently recirculated for anonymous comment and revision, assembled by a third party, and re-presented to the group for consensus.

RESULTS

Widely used definitions of shunt failure were extracted from previous randomized trials and prospective studies. Definitions for wound infections were extracted from the definitions from the Centers for Disease Control and Prevention. Postoperative neurological deficits were based on the Pediatric Stroke Outcome Measure. Other definitions were created and modified by consensus. These definitions are now currently in use across the Canadian Pediatric Neurosurgery Study Group centers in Morbidity and Mortality data collection and for subsequent comparison studies.

CONCLUSIONS

Coming up with consensus definitions of complications in pediatric neurosurgery is a first step in improving the quality of outcomes. It is a dynamic process, and further refinements are anticipated. Center to center comparison will hopefully allow significant variations in outcomes to be identified and acted upon.

Endoscopic fenestration of cavum velum interpositum cysts: a case study of two symptomatic patients

INTRODUCTION

Cavum velum interpositum (CVI) is commonly an incidental asymptomatic finding on imaging studies. Encystment can occur and, in most situations, is also asymptomatic. Clinical symptoms occurring in patients with CVI cysts have been reported infrequently with the result that the relationship of these symptoms and the cyst are usually unclear. This report contributes to the knowledge base of symptoms that can occur in patients with CVI and the response of symptoms to effective treatment.

PATIENTS AND METHODS

We report the clinical outcomes of a 3-year-old male patient and a 13-year-old female patient with symptoms and CVI cysts on imaging who were treated successfully with endoscopic fenestration.

RESULTS

The developmental delay and occasional headache present in the 3-year-old male patient resolved after endoscopic fenestration; however, the 13-year-old patient who had neuropsychiatric symptoms did not improve.

CONCLUSIONS

Our cases add to the literature describing the response to cyst treatment in symptomatic patients harboring CVI cysts. Symptoms due to CSF pathway obstruction may respond to cyst fenestration, while the response of symptoms in patents who do not have clear CSF circulation disorders is less predictable.

Spinal cord infarction remote from maximal compression in a patient with Morquio syndrome

Morquio syndrome, or mucopolysaccharidosis type IV, is a rare enzyme deficiency disorder and results in skeletal dysplasia. Odontoid dysplasia is common among affected patients, resulting in atlantoaxial instability and spinal cord compression. Surgical treatments include decompression and prophylactic fusion, during which intraoperative neuromonitoring is important to alert the surgical team to changes in cord function so that they can prevent or mitigate spinal cord injury. This report describes a 16-year-old girl with Morquio syndrome who developed paraplegia due to thoracic spinal cord infarction during foramen magnum and atlantal decompression. This tragic event demonstrates the following: 1) that patients with Morquio syndrome are at risk for ischemic spinal cord injury at levels remote from areas of maximal anatomical compression while under anesthesia in the prone position, possibly due to impaired cardiac output; 2) the significance of absent motor evoked potential responses in the lower limbs with preserved upper-limb responses in an ambulatory patient; 3) the importance of establishing intraoperative neuromonitoring baseline assessments prior to turning patients to the prone position following induction of anesthesia; and 4) the importance of monitoring cardiac output during prone positioning in patients with chest wall deformity.

Identification by families of pediatric adverse events and near misses overlooked by health care providers

BACKGROUND

Identifying adverse events and near misses is essential to improving safety in the health care system. Patients are capable of reliably identifying and reporting adverse events. The effect of a patient safety reporting system used by families of pediatric inpatients on reporting of adverse events by health care providers has not previously been investigated.

METHODS

Between Nov. 1, 2008, and Nov. 30, 2009, families of children discharged from a single ward of British Columbia's Children's Hospital were asked to respond to a questionnaire about adverse events and near misses during the hospital stay. Rates of reporting by health care providers for this period were compared with rates for the previous year. Family reports for specific incidents were matched with reports by health care providers to determine overlap.

RESULTS

A total of 544 familes responded to the questionnaire. The estimated absolute increase in reports by health care providers per 100 admissions was 0.5% (95% confidence interval -1.8% to 2.7%). A total of 321 events were identified in 201 of the 544 family reports. Of these, 153 (48%) were determined to represent legitimate patient safety concerns. Only 8 (2.5%) of the adverse events reported by families were also reported by health care providers.

INTERPRETATION

The introduction of a family-based system for reporting adverse events involving pediatric inpatients, administered at the time of discharge, did not change rates of reporting of adverse events and near misses by health care providers. Most reports submitted by families were not duplicated in the reporting system for health care providers, which suggests that families and staff members view safety-related events differently. However, almost half of the family reports represented legitimate patient safety concerns. Families appeared capable of providing valuable information for improving the safety of pediatric inpatients.

Time to listen: a review of methods to solicit patient reports of adverse events

BACKGROUND

Patients have been shown to report accurate observations of medical errors and adverse events. Various methods of introducing patient reporting into patient safety systems have been published with little consensus among researchers on the most effective method. Terminology for use in patient safety reporting has yet to be standardised.

METHODS

Two databases, PubMed and MEDLINE, were searched for literature on patient reporting of medical errors and adverse events. Comparisons were performed to identify the optimal method for eliciting patient initiated events.

RESULTS

Seventeen journal publications were reviewed by patient population, type of healthcare setting, contact method, reporting method, duration, terminology and reported response rate.

CONCLUSION

Few patient reporting studies have been published, and those identified in this review covered a wide range of methods in diverse settings. Definitive comparisons and conclusions are not possible. Patient reporting has been shown to be reliable. Higher incident rates were observed when open-ended questions were used and when respondents were asked about personal experiences in hospital and primary care. Future patient reporting systems will need a balance of closed-ended questions for cause analysis and classification, and open-ended narratives to allow for patient's limited understanding of terminology. Establishing the method of reporting that is most efficient in collecting reliable reports and standardising terminology for patient use should be the focus of future research.

Third ventricular shape: a predictor of endoscopic third ventriculostomy success in pediatric patients

OBJECT

The criteria for identifying patients in whom endoscopic third ventriculostomy (ETV) provides control of hydrocephalus remain in evolution. In particular, it is not clear when ETV would be effective if intraventricular obstruction is not found preoperatively. The authors postulated that 1) displacement of the third ventricle floor inferiorly into the interpeduncular cistern and displacement of the lamina terminalis anteriorly into the lamina terminalis cistern could predict clinical success of ETV, and 2) improvement in these displacements would correlate with the success of ETV.

METHODS

Magnetic resonance imaging in 38 consecutive patients treated between 2004 and 2010 was reviewed to assess displacement of the lamina terminalis and third ventricular floor prior to and following ETV. Displacements of the floor and lamina terminalis were judged qualitatively and quantitatively, using a newly created index, the Third Ventricular Morphology Index (TVMI). The association between the aforementioned morphological features and clinical success of ETV was analyzed.

RESULTS

Ninety-six percent of patients in whom the authors preoperatively observed displacement of the lamina terminalis and the third ventricular floor were successfully treated with ETV. Displacements of the third ventricular floor and lamina terminalis, as judged qualitatively, correlated with the clinical success of ETV. The TVMI correlated with the qualitative assessments of displacement. Postoperative decrease in the TVMI occurred in the majority of successfully treated patients. Changes in third ventricular morphology preceded changes in other measures of third and lateral ventricular volume following ETV.

CONCLUSIONS

Assessment of third ventricular floor and lamina terminalis morphology is useful in predicting clinical success of ETV and in the follow-up in treated patients. The TVMI provided a quantitative assessment of the third ventricular morphology, which may be useful in equivocal cases and in research studies.

Does treatment with endoscopic third ventriculostomy result in less concern among parents of children with hydrocephalus?

PURPOSE

A possible benefit of endoscopic third ventriculostomy (ETV) is that families might harbor less concern and anxiety compared to shunt. This has not yet been demonstrated, however. Our goal was to compare parental concern in a large sample of children with hydrocephalus treated with ETV or shunt, using our previously developed measure of parental concern, the Hydrocephalus Concerns Questionnaire for Parents (HCQ-P).

METHODS

The parents of children 5-18 years old with previously treated hydrocephalus at three Canadian pediatric neurosurgery centers completed the HCQ-P. HCQ-P scores were compared between those who were initially treated with ETV and those initially treated with shunt. A multivariable linear regression analysis was used to adjust for center, current age, age at initial hydrocephalus surgery, seizures, etiology, hydrocephalus complications, and quality of life.

RESULTS

Six hundred three families participated (58 ETV [9.6%], 545 shunt [90.4%]). In unadjusted comparison, ETV parents had lower overall concern (HCQ-P = 0.41 versus 0.51, p = 0.02). After adjustment for multiple patient factors, ETV parents still had lower concern (p = 0.03) but the only questions for which there was a still a statistically significant difference were those related to concerns about shunt/ETV complications.

CONCLUSIONS

Parents of children who have had ETV experience less concern than those who have had shunt and this is due almost exclusively to less concern about hydrocephalus treatment complications. While this could be interpreted as a beneficial aspect of ETV treatment, it remains important for neurosurgeons to ensure that parents are not being overly complacent about the possibility of ETV failure requiring urgent treatment.

Quality of life after endoscopic third ventriculostomy and cerebrospinal fluid shunting: an adjusted multivariable analysis in a large cohort

OBJECT

Quality of life (QOL) studies comparing treatment with endoscopic third ventriculostomy (ETV) and CSF shunting are very limited. The authors compared QOL outcomes following these 2 treatments in a large cohort of children with hydrocephalus by using multivariable statistical techniques to adjust for possible confounder variables.

METHODS

The families of children between 5 and 18 years of age with previously treated hydrocephalus at 3 Canadian pediatric neurosurgery centers completed measures of QOL: the Hydrocephalus Outcome Questionnaire (HOQ) and the Health Utilities Index Mark 3 (HUI3). Medical records and recent brain imaging studies were reviewed. A linear regression analysis was performed with the QOL measures as the dependent variable. In multivariable analyses, the authors assessed the independent effect of initial hydrocephalus treatment (ETV vs shunting) while adjusting for the treatment center, current patient age, age at initial treatment, etiology of hydrocephalus, total number of days spent in the hospital for initial treatment, total number of days spent in the hospital for subsequent hydrocephalus complications, functioning ETV at follow-up assessment, frequency of seizures, and current ventricle size.

RESULTS

Data from 603 patients were available for analysis. Fifty-eight patients had undergone ETV as their primary treatment and 545 had undergone CSF shunting. Endoscopic third ventriculostomy patients were slightly younger at the follow-up assessment, were older at the first surgery, and spent fewer days in the hospital for hydrocephalus complications. Without adjustment for any confounders, treatment with ETV was associated with significantly higher HOQ physical scores and HUI3 scores. After multivariable adjustment, however, there was no significant difference in any outcome measure. A functioning ETV at the time of the follow-up assessment was not significant in any model.

CONCLUSIONS

Treatment with either ETV or CSF shunting does not appear to be associated with any substantial difference in QOL outcome after adjusting for prognostic factors. Further study is needed to definitively determine the relative QOL benefit of either procedure, if any.

A human factors and survey methodology-based design of a web-based adverse event reporting system for families

PURPOSE

Adverse event reporting systems allow healthcare institutions to detect and prevent recurrence of avoidable patient harm. It is known that standard reporting systems, which are initiated by clinicians, detect only a minority of chart-documented adverse events. The objective of the study was to develop a web-based system, the Family Reporting System (FRS), to elicit adverse event reports from families of children admitted to hospital through survey methodology and human factors engineering techniques.

MEASUREMENTS

Face validity and usability were measured via standardized survey instruments. Utility was measured via the rate, typology, degree of harm, likelihood of recurrence, quality of information, and inter-rater agreement analysis of the reported events.

RESULTS

The FRS has good face validity, excellent usability, and good clinical utility.

CONCLUSION

The application of survey and human factors methodologies to the design of an electronic system is an effective means of developing an electronic adverse event reporting system for the use of families of pediatric patients.

Clinical, radiologic and pathologic features and outcome following surgery for cervicomedullary gliomas in children

INTRODUCTION

Surgical resection is generally recommended for cervicomedullary tumors, but morbidity of resection may be significant. This study sought to identify MRI characteristics that might predict morbidity and extent of resection.

MATERIALS AND METHODS

A retrospective review was performed of MRI findings, histopathology, extent, and morbidity of resection in cervicomedullary gliomas undergoing resection during 1985-2008.

RESULTS

Of 78 brainstem tumors, nine cervicomedullary tumors undergoing resection were identified: two pilocytic astrocytomas, two gangliogliomas, and five grade II astrocytomas. Mean age was 6.3 years (range 1.7-11.2 years). Initial treatment was surgery in seven: biopsy (1), <25% resection (4), and 25-50% resections (2). Bulbar worsening occurred in five of six patients with interposed areas of non-enhancement versus one of three patients without interposed non-enhancing tissue (P = 0.014). Additionally, bulbar worsening occurred in five of five patients with a poorly defined tumor/brainstem interface and abnormal low T1 signal extending beyond obvious tumor into the brainstem versus one of four with a well-defined tumor margin (P = 0.008). Following chemo- or radiotherapy, the definition of the brainstem/tumor interface improved. In four patients undergoing surgery after chemo/radiotherapy, more extensive resections were achieved without neurologic worsening: >80% in three and 30% in one.

CONCLUSION

A less aggressive initial surgical approach, supplemented by postoperative chemotherapy, designed to preserve brainstem function, is proposed for patients with interposed non-enhancing tissue continuous with normal cervical cord or medulla and/or a poorly defined ventral tumor/brainstem interface with abnormal low T1 signal extending beyond obvious tumor into the brainstem.

Predicting postresection hydrocephalus in pediatric patients with posterior fossa tumors

OBJECT

Approximately 30% of children with posterior fossa tumors exhibit hydrocephalus after tumor resection. Recent literature has suggested that prophylactic endoscopic third ventriculostomy diminishes the risk of this event. Because the majority of patients will not have postoperative hydrocephalus, a preoperative clinical prediction rule that identifies patients at high or low risk for postresection hydrocephalus would be helpful to optimize the care of these children.

METHODS

The authors evaluated a derivation cohort of 343 consecutive children with posterior fossa tumors who underwent treatment between 1989 and 2003. Multivariate methods were used on these data to generate the Canadian Preoperative Prediction Rule for Hydrocephalus. The rule's estimated risk of postresection hydrocephalus was compared with risk observed in 111 independent patients in the validation cohort.

RESULTS

Variables identified as significant in predicting postresection hydrocephalus were age < 2 years (score of 3), papilledema (score of 1), moderate to severe hydrocephalus (score of 2), cerebral metastases (score of 3), and specific estimated tumor pathologies (score of 1). Patients with scores > or = 5 were deemed as high risk. Predicted probabilities for the high- and low-risk groups were 0.73 and 0.25, respectively, from the derivation cohort, and 0.59 and 0.14 after prevalence adjustment compared with the observed values of 0.42 and 0.17 in the validation cohort.

CONCLUSIONS

A patient's score on the Preoperative Prediction Rule for Hydrocephalus will allow improved patient counseling and surgical planning by identifying patients at high risk of developing postresection hydrocephalus. These patients might selectively be exposed to the risks of preresection CSF diversion to improve outcome.

Medical, social, and economic factors associated with health-related quality of life in Canadian children with hydrocephalus

OBJECTIVE

To study the factors associated with health-related quality of life (HRQL) in Canadian children with hydrocephalus, using a comprehensive model of determinants of child health, including socioeconomic factors.

STUDY DESIGN

A cross-sectional study was performed between November 2005 and November 2006 at 3 Canadian pediatric hospitals. Parents of children with hydrocephalus age 5 to 18 years completed the Hydrocephalus Outcome Questionnaire (HOQ) and the Health Utilities Index Mark 3 (HUI-3).

RESULTS

A consecutive sample of 340 subjects participated from a total of 366 eligible children (mean age, 11.6 +/- 3.6 years; mean time from the diagnosis of hydrocephalus, 10.0 +/- 4.6 years). Adjusted multivariate linear regression models demonstrated that the most important determinants of poorer HRQL included lower family income, lower parental education, worse family functioning, seizures, myelomeningocele, and prolonged treatment for cerebrospinal fluid shunt obstruction.

CONCLUSIONS

Despite a national universal health care system, socioeconomic disparities remain important as determinants of HRQL. Given the absence of a parallel private health care system in Canada, this suggests that the impact of socioeconomic factors is related to issues other than access to care.

Comparing children's and parents' perspectives of health outcome in paediatric hydrocephalus

This study exampled the properties of a child-completed version of the Hydrocephalus Outcome Questionnaire (cHOQ) and compared these with parental responses to the HOQ (parent version). This was a cross-sectional study in the outpatient clinics at three Canadian paediatric hospitals (Toronto, Vancouver, and Halifax). All cognitively-capable children with previously treated hydrocephalus who were aged between 6 and 19 years were eligible. Parents completed the HOQ and the Health Utilities Index Mark 3; children completed the cHOQ. A total of 273 children participated (146 males, 127 females; mean age 14 y 1 mo, SD 2 y 7 mo). Internal consistency of the cHOQ was 0.93 and test-retest reliability was 0.86 (95% confidence interval 0.78-0.92). Mother-child agreement and father-child agreement were 0.57 (0.40-0.68) and 0.62 (0.48-0.73) respectively. Agreement was higher for assessments of physical health, but lower for assessments of cognitive health and social-emotional health. There was greater parent-child agreement for older children. When there was disagreement, it seemed that children tended to rate their health better than their parents did. In older children with hydrocephalus, the cHOQ appears to be a scientifically reliable means of assessing long-term outcome. The differences in child and parent perceptions of health need to be appreciated when conducting outcome studies in this population.

Significance of beaten copper appearance on skull radiographs in children with isolated sagittal synostosis

AIMS AND OBJECTIVES

The significance of beaten copper appearance (BCA) on skull radiographs in children following surgery for isolated sagittal craniosynostosis has not been studied. This study was designed to look for any correlation between BCA and symptoms suggestive of intracranial hypertension in this group of patients.

MATERIALS AND METHODS

Forty-eight consecutive children, who were operated for isolated sagittal synostosis from 1987 to 2000 and had postoperative skull radiographs, were included. Patients were divided into: (a) BCA group (n = 20), consisting of children who had beaten copper appearance on skull radiographs at last follow up, and (b) Non-BCA group (n = 28), consisting of children who did not have this finding. Records were reviewed to look for symptoms suggestive of intracranial hypertension, such as headache, head banging, and irritability.

RESULTS

Median age at surgery was 4.8 months for BCA group and 4 months for the non-BCA group. Follow up ranged from 4 to 156 months with a mean of 36.2 months. Total of 28.6% (n = 6) of the children with follow up radiographs done at < or =18 months of age had BCA. The incidence of BCA increased to 83.3% in children with skull radiographs performed after 48 months of age. In 18 (90%) children, the BCA was 'diffuse' with 5 (25%) children having the maximum possible score of 8. In the BCA group, 45% (n = 9) had symptoms compared to 10.7% (n = 3) in the control group (p = 0.0068).

CONCLUSIONS

This study suggests a significant number of children with BCA on radiographs develop symptoms suggestive of raised ICP following surgical treatment in infancy and prolonged follow up may be warranted in this group of patients.

Cord untethering for lipomyelomeningocele: expectation after surgery

✓Tethering of the conus medullaris is assumed to be the primary cause of the deterioration seen in children with transitional lipomyelomeningocele (LMMC). The inevitability of deterioration has led to the use of prophylactic interventions to stabilize or prevent further clinical deterioration. The author reviewed current literature to define the timing and pattern of deterioration prior to and following initial cord untethering in patients with transitional LMMC, as well as the operative burden that these children bear in exchange for optimized function.

Ascites and abdominal pseudocysts following ventriculoperitoneal shunt surgery: variations of the same theme

OBJECT

Ascites and abdominal pseudocysts are two complications that can occur following placement of a ventriculoperitoneal (VP) shunt. Although various factors have been implicated, the exact pathogenesis of the two conditions remains elusive. To the authors' knowledge, there are no studies in which these two obviously related conditions have been compared.

METHODS

The authors retrospectively reviewed the cases of children with abdominal complications caused by a VP shunt. There were 15 patients who developed a pseudocyst and five patients who developed ascites. The cases were analyzed to identify common and distinguishing factors that may help in identifying the mechanism involved. Abdominal symptoms were the mode of presentation for patients with ascites, whereas shunt malfunction was the mode of presentation in 60% of those with pseudocysts. Culture-proven infection, abdominal surgery, and the number of revisions seemed to be more common in cases with pseudocysts than in ascites. The fluid in ascites was found to be a transudate irrespective of the origin of hydrocephalus. Alternative drainage sites were required in the treatment of patients with ascites, and reimplantation in the peritoneum was possible in 66.7% of those with pseudocysts. In the long-term, however, peritoneal reimplantation was possible in three of the five patients with ascites.

CONCLUSIONS

Abdominal pseudocysts and ascites, after VP shunt treatment, are distinct conditions with different modes of presentation and findings during examination of fluid, and therefore they require different management strategies.

EARLY HYPODENSITY ON COMPUTED TOMOGRAPHIC SCAN OF THE BRAIN IN AN ACCIDENTAL PEDIATRIC HEAD INJURY

OBJECTIVE

Hypodensities on computed tomographic (CT) brain scans are thought to take at least 6 hours to become apparent after blunt head trauma. This finding, in conjunction with the later evolution of the hypodensities, is used in timing the injury in children with suspected non-accidental brain injury, in whom the history may be inaccurate. The purpose of this study is to report the occurrence of diffuse cerebral parenchymal hypodensities on CT scans performed within 5 hours of a well-defined accidental head injury.

METHODS

A retrospective review was performed of five patients admitted to British Columbia Children's Hospital who had accidental head injury and who were identified as having diffuse cerebral hemispheric hypodensities on early CT scans.

RESULTS

We present five patients (age range, 4 mo-14 yr) with well-documented accidental head injuries who demonstrated obvious and extensive CT brain scan cerebral hemispheric hypodensity from 60 minutes to 4.5 hours after trauma. All five patients presented with severe head injuries and immediate, unremitting coma, and all five progressed rapidly to brain death within 48 hours.

CONCLUSION

It is unusual, but possible, to develop CT hypodensities as early as 1 hour after accidental head injury. In our small series of cerebral hemispheric hypodensity occurring less than 5 hours after trauma, all five patients had a uniformly fatal outcome. These observations may be important medicolegally in the assessment of the timing of head injury when the history of the trauma is not clear, as in children with suspected non-accidentally inflicted injury. It is inappropriate to generalize these findings to patients who are not unconscious immediately after a head injury, who regain consciousness after an injury before deteriorating, or who do not progress rapidly to brain death.

Cerebrospinal fluid (CSF) leak and pseudomeningocele formation after posterior fossa tumor resection in children: a retrospective analysis

OBJECTIVE

The purpose of this study was to determine the incidence of pseudomeningocele and cerebrospinal fluid (CSF) leak after posterior fossa tumor surgery and to analyze factors that may be associated with these conditions. In particular, we wished to determine if there was evidence to support the hypothesis that the use of tissue glue, dural grafts, or external ventricular drainage (EVD) prevented CSF from leaking outside the closed dura.

MATERIALS AND METHODS

A retrospective chart review was carried out of posterior fossa tumor resections at British Columbia's Children's Hospital. Information was collected regarding tumor location, surgical approach, CSF diversion, dural grafting, and use of tissue glue. Multiple univariate analyses and step-wise logistic regression were performed to identify factors associated with pseudomeningocele formation or CSF leak. A pseudomeningocele was said to be present if it was noted in the clinical records or if a fluid collection was present superficial to the craniotomy flap on a postoperative CT or MR scan.

RESULTS

Out of 174 posterior fossa operations, 53 pseudomeningoceles with or without CSF leak were identified along with five CSF leaks in the absence of pseudomeningocele (33%). None of the factors examined reached statistical significance, although there was a trend towards higher rates in patients with external CSF drainage (P=0.06631), dural graft usage (p=0.06492), and patients in whom tissue glue was used (p=0.06181). On logistic regression, only tissue glue use and external CSF drainage were associated with increased incidence of pseudomeningocele and/or CSF leak.

CONCLUSION

In this retrospective study, the use of tissue glue, dural grafts, and external ventricular drainage was not associated with a reduced rate of clinically or radiologically diagnosed pseudomeningocele formation or postoperative CSF leak. The results of this study provide a basis for planning a randomized controlled trial to determine the effectiveness of tissue glue and/or dural grafting in preventing these complications.

Long-term anthropometric outcomes following surgery for isolated sagittal craniosynostosis

OBJECT

A number of studies have shown good short-term cosmetic outcomes following surgery for isolated sagittal craniosynostosis. Whether the improvement in head shape persists in the longer- term is less clear. The aim of this study was to investigate the long-term anthropometric outcomes following surgery for isolated sagittal craniosynostosis.

METHODS

Records were retrospectively reviewed for children with isolated sagittal synostosis who underwent surgical revision between 1987 and 2000. Only children who underwent surgery before 8 months of age and for whom serial anthropometric data (skull width, skull length, and cephalic index) were available were included in the study. The operative procedure consisted of vertex and parietal craniectomies involving removal of the sagittal suture and a 1.5- to 2.5-cm piece of adjacent parietal bone on each side as well as bilateral parietal barrel-stave osteotomies. Ninety cases satisfied the eligibility criteria. The mean age of the patients at surgery was 5 months (range 1.9-7.5 months). The mean preoperative cephalic index was 66.78. The follow-up period ranged from 1.8 to 167 months (mean 39.6 months). In 24 cases, the follow-up period was longer than 36 months. Eighteen (75%) and five (20.8%) of these 24 cases were followed up for longer than 5 and 10 years, respectively. The mean increase in cephalic index at the last follow up was 8.69% (p < 0.0001). The maximum improvement in the cephalic index occurred within 6 months of surgery, at which point it had improved by a mean of 11.1% (p < 0.0001). The cephalic index remained increased throughout the follow-up period, with a mean change of -1.84% (standard deviation, 4.28%; 99% confidence interval -3.33 to -0.37%) from the first postoperative to the final measurement.

CONCLUSIONS

Surgery for isolated sagittal craniosynostosis leads to a significant improvement in the cephalic index, which is most marked in the early postoperative period. Improvement in the cephalic index is still present after prolonged follow up.

Management of shunt infections: a multicenter pilot study

OBJECT

Approximately 10% of cerebrospinal fluid (CSF) shunt operations are associated with infection and require removal or externalization of the shunt, in-hospital treatment with antibiotic agents, and insertion of a new shunt. In a previous survey, the authors identified substantial variation in the duration of antibiotic therapy as well as the duration of hospital stay. The present multicenter pilot study was undertaken to evaluate current strategies in the treatment of shunt infection.

METHODS

Patients were enrolled in the study if they had a successful treatment of a CSF shunt infection proved by culture of a CSF specimen. Details of their care and the incidence of culture-proved reinfection were recorded. Seventy patients from 10 centers were followed up for 1 year after their CSF shunt infection. The initial management of the infection was shunt externalization in 17 patients, shunt removal and external ventricular drain insertion in 50, and antibiotic treatment alone in three. Reinfection occurred in 18 patients (26%). Twelve of the 18 reinfections were caused by the same organism and six were due to new organisms. The treatment time varied from 4 to 47 days, with a mean of 17.4 days for those who later experienced a reinfection compared with 16.2 days for those who did not. The most common organism (Staphylococcus epidermidis, 34 patients) was associated with a reinfection rate of 29% and a mean treatment time of 12.8 days for those who suffered reinfection and 12.5 days for those who did not.

CONCLUSIONS

Reinfection after treatment of a CSF shunt infection is alarmingly common. According to the data available, the incidence of reinfection does not appear to be related to the duration of antibiotic therapy.

Reformation of the sagittal suture following surgery for isolated sagittal craniosynostosis

OBJECT

Data from animal studies have shown that in experimentally induced craniosynostosis, removal of the involved calvaria results in the formation of new calvaria with time, and sutures redevelop in their normal anatomical positions. However, the pattern of suture reformation following surgery in humans with craniosynostosis remains ill-defined. The aim of this study was to determine the pattern of postoperative suture reformation in children who have undergone surgery for isolated sagittal synostosis and assess possible factors related to suture reformation.

METHODS

Records were retrospectively reviewed for 42 consecutive infants who had surgery for isolated sagittal synostosis between 1987 and 2000 and for whom postoperative skull radiographs were available. The radiographs were evaluated for sagittal suture morphology and patency of the coronal and lambdoid sutures. Surgery involved at a minimum 1) a vertex craniectomy, characterized by removal of the sagittal suture and a 1.5- to 2.5-cm piece of adjacent parietal bone with the attached pericranium bilaterally, and 2) parietal osteotomies and/or craniectomies. The median age at surgery was 3.9 months (range 1.9-7.6 months). The mean duration of follow up was 32.2 months (range 6-144 months). The sagittal suture had reformed in only seven (16.7%) of the children at follow up. In the other 35 (83.3%), the craniectomized bone defects had reossified without any part of the sagittal suture being visible on the radiographs.

CONCLUSIONS

There is a very low incidence of suture reformation in children after surgery for isolated sagittal craniosynostosis. Genetic predisposition, inclusion of undiagnosed syndromic patients, and current operative techniques may be some of the factors responsible for the low incidence of suture reformation seen in this series.

Etiological differences between the isolated lateral ventricle and the isolated fourth ventricle

OBJECTIVE

To determine if an etiological difference exists between isolation of the lateral ventricle and isolation of the fourth ventricle after ventricular shunting.

METHODS

Cases of symptomatic isolation of the lateral and fourth ventricles were reviewed retrospectively. The ages at presentation of ventricular isolation, the time course to development of isolation, the number of shunt surgeries leading up to symptomatic isolation, the types of shunt valves utilized, and the background of infection were analyzed.

RESULTS

Twenty-six patients had lateral ventricle isolation and 11 patients had fourth ventricle isolation. Infection, hemorrhage, Chiari malformation/myelomeningocele, and aqueductal stenosis were factors contributing to hydrocephalus requiring treatment in these patients. Compared to 26.9% of patients with lateral ventricle isolation, 90.9% of patients with fourth ventricle isolation had a previous history of infection.

CONCLUSIONS

Prior meningitis and ventriculitis frequently contributed to fourth ventricle isolation. Lateral ventricle isolation seems to arise from functional obstruction of the foramen of Monro related to prior shunting.

Shunt insertion in the summer: is it safe?

OBJECT

The potential for increased complications related to the arrival of new residents in July each year has not previously been demonstrated in the neurosurgical literature. The authors investigated this phenomenon in children undergoing cerebrospinal fluid shunt surgery.

METHODS

Data were obtained from a multicenter hydrocephalus clinical trials database and from hospital admission records in English-speaking Canada. Data pertaining to patients treated in July and August were compared with those pertaining to patients treated during the remainder of the year. The incidence of shunt failure, shunt infection, neurological deficits, wound infection, technical errors, and death were compared using a chi-square test for categorical outcomes, means for continuous outcomes, and survival analysis for time-dependent outcomes. In the hydrocephalus clinical trials database, 138 of 737 patients were treated in July and August. The median duration of shunt lifespan (hereafter referred to as "shunt survival") was 1.7 years for patients treated during the summer months and 2.4 years for those treated throughout the rest of the year (p = 0.10); for shunt infection the figures were 13.8 and 8.8% (p = 0.08) of the total number of cases, and for wound dehiscence they were 2.9 and 0.7% (p = 0.05), respectively. When all shunt procedures were included, an examination of shunt survival and infection incidence rates recorded in the Canadian Hospital Discharge Database seemed to imply a significant advantage to having surgery between September and June (log-rank statistic = 7.10, p = 0.008).

CONCLUSIONS

The data suggest a "July effect" on some outcomes related to shunt surgery, but the effect was small. Nonetheless, the potential morbidity of shunt failure, infection, and the cost of treatment indicate that continued vigilance and appropriate supervision of new staff by attending surgeons is warranted.

Traumatic retroclival epidural hematoma - a pediatric entity?

BACKGROUND

Traumatic retroclival epidural hematoma is very rare and only a few cases are described in literature. All previous cases occurred in the pediatric population and were classically seen in pedestrians or cyclists hit by speeding motor vehicles. It is probable that horizontal articulation between the cranium and the atlas and ligamentous laxity at the craniocervical junction in this age group predispose them to ligamentous injury at the craniospinal junction and formation of retroclival hematoma. MRI or three-dimensional reconstructed CT is considered essential for diagnosing this condition. Conservative treatment is an option if neurological deficits are mild and brainstem compression is not significant. Bony fixation is, however, required if there is suspicion of instability.

CASE REPORT

The authors describe the case of an 8-year-old girl who developed traumatic retroclival epidural hematoma after a motor vehicle accident and who was managed conservatively with good recovery.

CONCLUSION

This case and the review of literature suggest that retroclival epidural hematoma is a pediatric entity usually associated with ligamental injury at the craniocervical junction.

Diagnosis of isolated sagittal synostosis: are radiographic studies necessary?

AIMS AND OBJECTIVES

Isolated sagittal synostosis can be diagnosed easily on clinical grounds. This study was designed to determine if children could be operated on based solely on a clinical diagnosis or whether such an approach would result in any potentially unnecessary surgeries.

MATERIALS AND METHODS

Records of 114 consecutive children operated on for isolated nonsyndromic sagittal synostosis over a 14-year period (1987-2000) were reviewed to see whether the clinical findings were in concordance with the intraoperative findings and histopathology of the sagittal suture.

RESULTS

The age at surgery ranged from 1.9 to 81.3 months (median 4.3 months). Preoperative skull radiographs were done in 78 children and computer tomography (CT) scans of the head in 12 children. One hundred percent of the skull radiographs and 83.3% of the CT scans were completed prior to referring the children to a pediatric neurosurgeon. CT scans confirmed the diagnosis in all patients in whom it was available. For the rest, pathology reports and/or operative records were available for 108 (94.7%) children and were confirmatory for sagittal craniosynostosis in all.

CONCLUSIONS

Accurate diagnosis of isolated sagittal synostosis can be made clinically, and operative correction can proceed without a need for radiological investigations, unless the clinical features are not completely typical. This approach could result in significantly reduced radiation exposure for the developing brain and could provide economic benefits to health care providers.

Pseudoclosure of anterior fontanelle by wormian bone in isolated sagittal craniosynostosis

AIMS AND OBJECTIVES

Although syndromic craniosynostosis is one of the causes for early closure of the anterior fontanelle, there is no literature on the incidence and causes of fontanelle closure in isolated single-suture craniosynostosis. The objective of this study was to review the incidence of fontanelle closure by a wormian bone in isolated, nonsyndromic sagittal craniosynostosis.

MATERIALS AND METHODS

Intraoperative records of 100 consecutive children under 1 year of age, operated for isolated sagittal synostosis over a 14-year period (1987- 2000), were reviewed to identify the presence of a wormian bone closing the anterior fontanelle.

RESULTS

The median age at surgery was 4.2 months with a range of 1.9-11.7 months. Intraoperatively, a wormian bone was seen replacing the anterior fontanelle in 4 cases giving an incidence of 4%.

CONCLUSIONS

A wormian bone can occupy the anterior fontanelle in children with isolated sagittal craniosynostosis giving the appearance of a 'closed fontanelle'.