Neurosurgery Blog

Neurosurg Focus 29 (1):E9, 2010. (10.3171/2010.3.FOCUS1085)

The definition of tethered cord syndrome (TCS) relies mainly on radiological criteria and clinical picture. The presence of a thickened filum terminale and a low-lying conus medullaris in symptomatic patients is indicative of TCS. The radiological definition of TCS does not take into account cases that involve a normal-lying conus medullaris exhibiting symptoms of the disease.

Methods. The authors performed a MEDLINE search using the terms “tethered cord” and “pathophysiology.” The search returned a total of 134 studies. The studies were further filtered to identify mostly basic research studies in animal models or studies related to the biomechanics of the filum terminale and spinal cord.

Results. Spinal cord traction and the loss of filum terminale elasticity are the triggers that start a cascade of events occurring at the metabolic and vascular levels leading to symptoms of the disease. Traction on the caudal cord results in decreased blood flow causing metabolic derangements that culminate in motor, sensory, and urinary neurological deficits. The untethering operation restores blood flow and reverses the clinical picture in most symptomatic cases.

Conclusions. Although classically defined as a disease of a low-lying conus medullaris, the pathophysiology of TCS is much more complex and is dependent on a structural abnormality, with concomitant altered metabolic and vascular sequelae. Given the complex mechanisms underlying TCS, it is not surprising that the radiological criteria do not adequately address all presentations of the disease.

J Neurosurg Pediatrics 5:474-478, 2010. DOI: 10.3171/2010.1.PEDS09218

The optimal surgical management of Chiari malformation (CM) is evolving. Evidence continues to accrue that supports decompression without duraplasty as an effective treatment to achieve symptomatic relief and anatomical decompression. The risks and benefits of this less invasive operation need to be weighed against decompression with duraplasty.

Methods. The authors performed a retrospective review of all CM decompressions from 2003 to 2007. All operations were performed by a single surgeon at a single institution. Data were analyzed for outcome, postoperative morbidity, and recurrence.

Results. Of 121 unique patients, 56 underwent posterior fossa decompressions without duraplasty (PFD) and 64 patients underwent posterior fossa decompressions with duraplasty (PFDD). Of the 56 PFD patients, 7 (12.5%) needed a subsequent PFDD for symptomatic recurrence. Of the 64 patients who underwent a PFDD, 2 (3.1%) needed a repeated PFDD for symptomatic recurrence. Patients treated with PFDD had an average operative time of 201 minutes in contrast to 127 minutes for those who underwent PFD (p = 0.0001). Patients treated with PFDD had average hospital stays of 4.0 days, whereas that for patients treated with PFD was 2.7 days (p = 0.0001). While in the hospital, patients treated with PFDD used low-grade narcotics, intravenous narcotics, muscle relaxants, and antiemetic medications at statistically significant differing rates.

Conclusions. While PFD was associated with a higher rate of recurrent symptoms requiring repeated decompression, this may be justified by the significantly lower morbidity rate. Clearer delineation of the trade-off between morbidity and recurrence may be used to help patients and their families make decisions regarding care.

Neurosurgery. 66(5):999-1004, May 2010. DOI: 10.1227/01.NEU.0000368443.43565.2A

Advances in medicine have largely followed advances in technology. Medical strides have been made when physicians and researchers have adapted growing science to target specific problems. A new medical field, telemedicine, has emerged that links physicians with colleagues and patients. Cell phone technology is affordable for almost everyone, and basic models include digital photography.

OBJECTIVE: We present a case series exhibiting the utility of digital pictures taken with patients’ cell phones.

CLINICAL PRESENTATION: Our patients had wound infections requiring daily intravenous antibiotics and dressing changes. Previously, these patients would have required prolonged hospitalizations. Currently, patients with these infections are discharged from the hospital, but close outpatient observation is required to monitor the wound. Our patients lived up to 8 hours away from the hospital. Daily appointments for wound checks in the clinic were impractical. Wounds were monitored via cell phone images without the inconvenience of travel and the expense of a local hotel, and unnecessary appointments in the clinic.

INTERVENTION: Wound evaluations were conducted with the patients’ cell phone cameras. These images were transmitted to the surgeon by text messaging and emails.

CONCLUSION: This application of cell phone technology has been documented in other literature and could become a legitimate method for close outpatient observation by neurosurgeons if medicolegal issues are addressed.

Childs Nerv Syst (2010) 26:681–687.DOI 10.1007/s00381-009-1039-8

The purpose of this study was to review our experience with a multimodality treatment approach in the management of cerebral arteriovenous malformation (AVM) in children.

Methods We retrospectively analysed a consecutive series of 56 children who harboured a cerebral AVM and were treated at our institution between 1988 and 2008. During the whole treatment period, a combined treatment strategy, including microsurgery, endovascular treatment and gamma knife radiosurgery, was used.

Results Of the 56 patients (median age, 14.0; range, 3 months–18 years) reported, 36 (64.3%) were admitted after AVM rupture; of these, only one AVM (1.8%) was considered untreatable. In 30.9% (17/55) of the treated patients, a single treatment measure was sufficient to attain angiographic cure of the AVM. Among these, six patients (10.9%) had microsurgical AVM resection, four patients (7.3%) underwent endovascular treatment, and another seven patients (12.7%) underwent radiosurgical management of the AVM. The majority of the population (38/55; 69.1%) underwent combined treatment: 21 patients (38.2%) received embolisation followed by radiosurgery of the remnant nidus, ten patients (18.2%) underwent embolisation with subsequent surgical resection of the residual AVM, three patients (5.5%) had radiosurgery after incomplete surgical AVM nidus resection and another four patients (7.3%) required a combination of all three treatment modalities to achieve permanent angiographic cure of the AVM. We observed good clinical outcomes (Glasgow Outcome Scale 5 and 4) in 94.6% of the children. Complete angiographic obliteration was achieved in 93.3% of the patients treated.

Conclusion A multimodality treatment approach in children harbouring cerebral AVMs leads to excellent angiographic and clinical outcomes.

Neurosurg Focus 28 (4):E3, 2010. DOI: 10.3171/2010.1.FOCUS09303

Obesity as a consequence of management of pediatric craniopharyngioma is a well-described phenomenon related to the degree of hypothalamic involvement. However, weight change and obesity have not been analyzed in adult patients. Therefore, the purpose of this study was 1) to evaluate the pattern of postoperative weight gain related to preoperative body mass index (BMI), 2) determine if postoperative weight gain is an issue in adult patients, and 3) develop an objective MR imaging grading system to predict risk of postoperative weight gain and obesity in adults treated for craniopharyngioma.

Methods. The authors retrospectively screened 296 patients with known craniopharyngioma for the following inclusion criteria: pathologically confirmed craniopharyngioma, index surgery at the authors’ institution, and operative weight and height recorded with at least 3 months of follow-up including body weight measurement. Patients aged 18 years or younger were excluded, yielding 28 cases for analysis. Cases of craniopharyngiomas were compared with age- and sex-matched controls (pituitary adenoma patients) to evaluate the pattern and significance of perioperative weight changes.

Results. Mean age was 46 ± 17 years at surgery, and 64% of the patients were male. Complete resection was achieved in 71% of cases. There was no correlation of preoperative BMI and postoperative weight gain testing in a linear model. Sixty-one percent and 46% of patients had postoperative weight gains greater than 4 and 9%, respectively. Comparing craniopharyngioma patients (cases) to age- and sex-matched controls, the preoperative BMIs were similar (p = 0.93) between cases (mean 28.9 [95% CI 30.9–26.9]) and controls (mean 29.3 [95% CI 31.9–26.7]). However, there was a trend to a greater mean postoperative weight change (percentage) in cases (10.1%) than in controls (5.6%) (p = 0.24). Hypothalamic T2 signal change and irregular contrast enhancement correlated and predicted higher-grade hypothalamic involvement. Furthermore, they can be used to objectively grade hypothalamic involvement as the authors propose. Progressive hypothalamic involvement correlated with larger postoperative weight gains (p = 0.022); however, hypothalamic involvement did not correlate with preoperative BMI (p = 0.5).

Conclusions. Postoperative weight gain in adult patients undergoing surgery for craniopharyngioma is a significant problem and correlates with hypothalamic involvement, as it does in pediatric patients. Finally, objective MR imaging criteria can be used to predict risk of postoperative weight gain and aid in grading of hypothalamic involvement.

Neurosurg Focus 28 (4):E12, 2010. (DOI: 10.3171/2010.1.FOCUS09310)

The authors assessed the efficacy of intratumoral interferon-α (IFNα)–based chemotherapy in pediatric patients with cystic craniopharyngiomas.

Methods. In a prospective multicenter study of 60 pediatric patients, the authors assessed the efficacy of intratumoral INFα2A-based chemotherapy. The study was conducted between 2000 and 2009 at 3 locations: the Medical School of the Federal University of São Paulo, Catholic University of Rome, and the Neurosurgery Institute of Santiago, Chile. The assessment included clinical and radiological control examinations, side effects observed, and total dose used.

Results. Sixty cases of cystic craniopharyngioma were analyzed. The cohort consisted of 35 male and 25 female children (mean age 11 years). Clinical and radiological improvement was achieved in 76% of the cases. New endocrinological deficits were observed in 13% of the cases. In approximately 30% of the patients, the evolution included some light side effects, the most common being headache (33%) and eyelid edema (28%). The number of cycles varied from 1 to 9 (mean 5 cycles), and the total dose applied per cycle was 36,000,000 IU.

Conclusions. This has been the largest documented series of intratumoral chemotherapy using INFα for the control of cystic craniopharyngiomas. The treatment has proved efficacious; there was no mortality, and morbidity rates were low.

J Neurosurg Pediatrics 5:02050–200540, 2010. DOI: 10.3171/2009.10.PEDS09187

Journal of Neurosurgery: Pediatrics. (DOI: 10.3171/2009.9.PEDS09196)

In Uganda, childhood hydrocephalus is common and difficult to treat. In some children, endoscopic third ventriculostomy (ETV) can be successful and avoid dependence on a shunt. This can be especially beneficial in Uganda, because of the high risk of infection and long-term failure associated with shunting. Therefore, the authors developed and validated a model to predict the chances of ETV success, taking into account the unique characteristics of a large sub-Saharan African population.

Methods. All children presenting with hydrocephalus at CURE Children’s Hospital of Uganda (CCHU) between 2001 and 2007 were offered ETV as first-line treatment and were prospectively followed up. A multivariable logistic regression model was built using ETV success at 6 months as the outcome. The model was derived on 70% of the sample (training set) and validated on the remaining 30% (validation set).

Results. Endoscopic third ventriculostomy was attempted in 1406 patients. Of these, 427 were lost to followup prior to 6 months. In the remaining 979 patients, the ETV was aborted in 281 due to poor anatomy/visibility and in 310 the ETV failed during the first 6 months. Therefore, a total of 388 of 979 (39.6% and [55.6% of completed ETVs]) procedures were successful at 6 months. The mean age at ETV was 12.6 months, and 57.8% of cases were postinfectious in origin. The authors’ logistic regression model contained the following significant variables: patient age at ETV, cause of hydrocephalus, and whether choroid plexus cauterization was performed. In the training set (676 patients) and validation set (303 patients), the model was able to accurately predict the probability of successful ETV (Hosmer-Lemeshow p value > 0.60 and C statistic > 0.70). The authors developed the simplified CCHU ETV Success Score that can be used in the field to predict the probability of ETV success.

Conclusions. The authors’ model will allow clinicians to accurately identify children with a good chance of successful outcome with ETV, taking into account the unique characteristics and circumstances of the Ugandan population.

Childs Nerv Syst (2010) 26:163–172.DOI 10.1007/s00381-009-0952-1

Purpose Middle fossa arachnoid cysts (MFAC) are a relatively common, benign pathology that pose a therapeutic challenge for both symptomatic and asymptomatic patients. The optimal surgical strategy and indication to treat are still debated by neurosurgeons. We reviewed our experience and results in a group of patients treated with endoscopic fenestration with the aim to assess indications to treat and clinical and neuroradiological results. Methods The data on 40 patients operated with endoscopic fenestration for MFAC in two centres, “Anna Meyer” Children’sHospital, Florence, Italy, and Royal Liverpool Children’s Hospital “Alder Hey”, Liverpool, UK, between 2001 and 2007 were retrospectively reviewed with prospective followup. We analysed clinical and neuroradiological presentation, indications to treat, surgical technique, complications, and clinical and neuroradiological follow-up. Results There were 30 males and ten females: mean age, 7.8 years; mean follow-up, 21 months. The neuronavigation system was used in 12 patients in the English cohort. Thirty-seven patients (92.5%) had a satisfactory clinical outcome. The cyst was reduced in size or completely disappeared in 29 patients (72.5%). There was no death or significant morbidity associated with the procedure. Four patients required further surgical treatment. Four patients experienced a post-traumatic intracystic bleeding after surgery. Conclusion Compared to microsurgical fenestration and cyst shunting, our experience with endoscopic fenestration was as effective and safe but less invasive. Each case must be assessed with its individual characteristics to define the optimal surgical strategy. Successful treatment may not reduce the risk of post-traumatic head injury haemorrhage.

Childs Nerv Syst (2010) 26:75–79.DOI 10.1007/s00381-009-0983-7

In the current literature, there are essentially no comparisons of quality of life (QOL) outcome after endoscopic third ventriculostomy (ETV) and shunt in childhood hydrocephalus. Our objective was to compare QOL in children with obstructive hydrocephalus, treated with either ETVor shunt. Methods A cross-sectional survey was conducted at SickKids, Toronto of children between ages five and 18 years, with obstructive hydrocephalus due to aqueductal obstruction and no other brain abnormalities. Measures of QOL were the Hydrocephalus Outcome Questionnaire and the Health Utilities Index Mark 3. A subset of patients was given the Wechsler Intelligence Scales for Children (WISC-IV). Results A total of 47 of 59 (80%) eligible patients participated (24 had ETV as primary treatment, 23 had shunt as primary treatment), with a mean age of 12.1 years (standard deviation 3.9) at assessment. The ETV group was older at initial surgery (p<0.001) and had larger ventricle size at last follow-up (p= 0.047). In all QOL measures, there were no significant differences between the ETV group and shunt group (all p≥ 0.09). Treatment failure, hydrocephalus complications, and the presence of a functioning ETV at assessment were not associated with QOL differences. Among the 11 children (six ETV, five shunt) who were given the WISC-IV, there were no significant differences between the scores of the ETV group and shunt group (all p≥0.11). Conclusions This is the first study to provide a meaningful comparison of QOL after ETV and shunt in children. These preliminary results suggest that there is no obvious difference in QOL after ETVand shunt.

Childs Nerv Syst (2010) 26:155–162. DOI 10.1007/s00381-009-0977-5

The optimal surgical management of sylvian arachnoid cysts is debated. We present our experience in children who were treated endoscopically, focusing on the limits and complications of this approach.

Materials and methods Seventeen children with a temporosylvian arachnoid cyst have been treated using a purely temporal endoscopic approach.

Results In all but one case, the recognition of anatomical landmarks was obtained at the insertion of the endoscope. In one child, the orientation and opening of the basal cisterns were more difficult due to the thickness and opacity of the membranes. Nevertheless, it was possible to perform the cysto-cisternostomy endoscopically in all children with several stomies in 13. In one child, a venous bleeding occurred. There were no other intraoperative complications. There were no postoperative cerebrospinal fluid leaks. In two patients, a symptomatic subdural collection developed which required a transient subdural-peritoneal shunt. No subdural collection was noted on a delayed follow-up (mean, 23 months). Preoperative symptoms related to the mass effect exerted by the cyst resolved in all children. Two children presented a recurrence, 12 and 20 months after endoscopic surgery, respectively. At the redo-endoscopy, the stomies were found to be closed. Their reopening resulted in the disappearance of the symptoms.

Conclusions An endoscopic approach can be used safely in the management of sylvian arachnoid cysts. An effective opening of the deep arachnoid membranes into the basal cisterns could be performed in all patients with the resolution of the preoperative symptoms. However, the long-term efficacy of the stoma needs to be assessed.

Childs Nerv Syst (2010) 26:19–28 DOI 10.1007/s00381-009-0990-8

This study described a 23-year experience in the treatment of children with pilocytic astrocytomas (piloA) with the aim of identifying putative clinical, histopathological, and/or immunohistochemical features that could be related to the outcome of these patients.

Methods Clinical data of 31 patients under 18 years of age with piloA were obtained from 1984 to 2006.

Results The mean age at the time of surgery was 7.8± 4.2 years (1 to 17 years), and the mean follow-up was 5.7± 5.4 years (1 to 20 years). The most common site of tumor formation was the cerebellum (17), followed by brainstem (4), optic chiasmatic hypothalamic region (4), cerebral hemisphere (3), cervical spinal cord (2), and optic nerve (1). Gross total resection (GTR) was achieved in 23 (74.1%), mainly in those with tumors located in the cerebellum and cerebral hemispheres (P=0.02). The global mortality rate was 6.4%. Nine patients were reoperated. Rosenthal fibers, eosinophilic granular bodies, microvascular proliferation, and lymphocytic infiltration were observed in most cases. The mean Ki-67LI was 4.4 ± 4.5%. In all cases, Gal-3 expression in tumor cells was observed with variable staining pattern.

Conclusions Aside from GTR, no other clinical, histopathological, or immunohistochemical features were found to be related to the prognosis. We postulate that strict follow- up is recommended if piloA is associated with high mitotic activity/Ki67-LI, or if GTR cannot be achieved at surgery. Tumor recurrence or progression of the residual lesion should be strictly observed. In some aspects, childhood piloA remains an enigmatic tumor.

J Neurosurg Pediatrics 5:4–16, 2010.(DOI: 10.3171/2008.7.17690)

This 25-year follow-up study was performed on 120 children with hypertensive hydrocephalus to evalu- ate the influence of the early prophylactic implantation of the Integra antisiphon device (ASD, Integra Neurosciences Ltd.) on the rate of proximal shunt obstructions and the frequency of symptomatic slit ventricle syndrome (SVS). The adaptability of the ASD to growth, proper positioning of the ASD as a necessity for its successful performance, and the 3 phases of SVS development are discussed.

Method. Since 1978, the ASD has consistently been implanted either at the time of primary shunt insertion (66 neonates, mean follow-up 11 years) or during revisions of preexisting shunts (54 children, mean follow-up 11.8 years). The complication rate among the 54 children before ASD implantation (mean follow-up 8.3 years) was com- pared with that among all 120 patients once an ASD had been inserted. Shunt complications were documented as ventricular catheter, distal catheter, and infectious complications.

Results. The study revealed a significant long-term reduction in ventricular catheter obstructions and hospitaliza- tions due to intermittent intracranial hypertension symptoms (symptomatic SVS) after both primary and secondary ASD implantation. Data in the study suggest that the high rate of ventricular catheter obstruction in pediatric shunt therapy is caused by hydrostatic suction induced by differential-pressure valve shunts during mobilization of the patient and that the development of a SVS can be traced back to this constant suction, which causes chronic CSF overdrainage and ventricular noncompliance. Recurrent ventricular catheter obstruction and SVS can be prevented by prophylactic supplementation of every shunt system with an ASD.

Conclusions. To inhibit chronic hydrostatic suction, to prevent overdrainage and proximal shunt obstruction, and to avoid SVS and thus improve the patient’s quality of life, the prophylactic implantation of an ASD in every pediatric hydrocephalus shunt is recommended.

J Neurosurg Pediatrics 4:050360–500420, 2009.(DOI: 10.3171/2009.7.PEDS0994)

Sinus pericranii (SP) is a rare venous varix in an extracranial location connected to the intracranial venous system. The aim of this retrospective study was to report on 16 pediatric cases of SP with consideration of the preoperative evaluation of surgical risk.

Methods. The study population consisted of 10 patients who had undergone surgery for SP and 6 patients with concomitant craniosynostosis and SP. The mean age of the patients at presentation was 3.7 years. To identify characteristics of SP with high operative risk, 8 cases in this report and 11 previously reported cases of SP with sufficient information were categorized on the basis of the number and size of SP, the number and size of transcranial channels, the venous drainage type, and the amount of blood loss. Hemorrhage amounts were classified into 3 grades based on the description of intraoperative blood loss.

Results. Sinus pericranii not associated with craniosynostosis were resected without any postoperative morbidity. Sinus pericranii associated with craniosynostosis were preserved. After craniofacial reconstruction, 2 cases of SP with craniosynostosis regressed, completely in one patient and partially in another. These 2 patients with SP were confirmed to have compromised intracranial sinus before craniofacial reconstruction. Among a total of 19 patients, multiplicity or size (> 6 cm) of SP (p = 0.036) and multiplicity (> 3) or size (> 3 mm) of transcranial channels (p = 0.004) was associated with more severe hemorrhage grade. Sinus pericranii with peripheral venous drainage (drainer type) was not associated with hemorrhage grade after classification into 3 grades (p = 0.192). However, all 3 cases of SP with massive Grade 3 hemorrhage were the drainer type. Hemorrhage grade was correlated with the number of risk factors for SP (r = 0.793, p < 0.001).

Conclusions. Three risk factors of SP and the presence of compromised intracranial sinus are markers for high-risk SP. “Squeezed-out sinus syndrome” is suggested as a concept for SP associated with compromised intracranial sinus, mainly caused by craniosynostosis. Sinus pericranii in squeezed-out sinus syndrome probably serves as a crucial alternative to venous drainage of the brain with intracranial venous compromise. Conservative treatment for such patients with SP is recommended.

Childs Nerv Syst. DOI 10.1007/s00381-009-1019-z

The outcome of endoscopic third ventriculostomy (ETV) is worse in children younger than 2 years old and especially in infants, and controversies still exist whether ETV might be superior to shunt placement in this age group. We retrospectively analyzed the data of 23 patients younger than 6 months of age treated with ETV and assessed its feasibility as a first choice of treatment for hydrocephalus.

Methods: Between 1994 and 2008 in our clinic, 23 patients younger than 6 months having presented with obstructive hydrocephalus were treated endoscopically. The etiology of hydrocephalus was congenital aqueduct stenosis in 11 patients, posthemorrhagic obstruction in six patients, myelomeningocele in two patients, postmeningitis in two patients, Chiari I malformation in one patients, and Dandy Walker variant in one patient. ETV was considered successful when no shunt operation was needed in the patient.

Results: ETV was successful in eight patients with regression of intracranial hypertension. In the remaining 15 patients ventriculoperitoneal shunt implantation was necessary. Total success rate in our group of patients was 34.8%. In patients younger than 3 months of age (n=12), success rate was 25.0%. In patients from 3 to 6 months of age (n=11), success rate was 45.5%. Complication included intraventricular hemorrhage in one patient, meningitis and cerebrospinal fluid leak in one patient, and meningitis in one patient.

Conclusions: Based on our experience, ETV could be the first method of choice for hydrocephalus in children younger than 6 months of age, especially in patients older than 3 months of age.

J Neurosurg Pediatrics 4:434-438, 2009. DOI: 10.3171/2009.6.PEDS08450

Osteoid osteomas and osteoblastoma of the spine are rare lesions in childhood, and management strategies have changed.

The authors reviewed their recent experience with these 2 types of lesions to elucidate current treatment modalities and outcomes.

Methods. Case records and radiographic images from all cases of osteoid osteoma and osteoblastoma diagnosed between 1993 and 2008 were retrospectively reviewed, including those managed nonsurgically.

Results. Thirty cases were identified; 22 were treated surgically and 8 were managed nonsurgically. The patients’mean age at presentation was 13 years (range 3–17 years). Of 30 patients, 29 (97%) presented with pain; 7 (23%) had scoliosis at presentation; 12 (40%) experienced relief with nonsteroidal antiinflammatory medication. Osteoid osteoma was diagnosed in 7 (32%) of the 22 patients who underwent surgery, and osteoblastoma in 15 (68%). Nine (41%) of the 22 surgically treated patients underwent fusion procedures (bone onlay or instrumentation) at the time of surgery. Pain freedom without medication had been achieved in 16 (73%) of the 22 surgically treated patients at a mean follow-up of 28 months (range 2–75 months) and was confirmed in 3 (38%) of the 8 nonsurgically treated patients at a mean follow-up of 33 months (range 24–51 months).

Conclusions. Osteoid osteomas and osteoblastomas can present challenging management problems in pediatric patients. In the majority of cases in which conservative therapy fails or pathological diagnosis is required, surgery using modern intraoperative imaging and spinal instrumentation can provide symptom relief and tumor control.

J Neurosurg Pediatrics 4:040580–400640, 2009.DOI: 10.3171/2009.6.PEDS0923

Because of their location and biological behavior, brainstem cavernous malformations (CMs) pose a formidable clinical challenge to the neurosurgeon. The optimal management of these lesions requires considerable neurosurgical judgment. Accordingly, the authors reviewed their experience with the management of pediatric brain- stem CMs at the Hospital for Sick Children.

Methods. The authors performed a retrospective chart review of pediatric patients who had received diagnoses of a brainstem CM at the Hospital for Sick Children over the past 20 years.

Results. Twenty patients were diagnosed with brainstem CMs. The mean age at diagnosis was 10.1 ± 5.4 years, and the patients included 13 boys and 7 girls. The mean maximal diameter of the CM was 14.3 ± 11.2 mm. The le- sions were evenly distributed on the right and left sides of the brainstem with 4 midbrain, 13 pontine, and 3 medullary lesions. Seven patients underwent surgery for the management of their CMs, with a mean age at presentation of 5.2 years, and a mean CM size of 21.0 mm. Of note from the surgical group, 2 patients had a family history of CMs, 2 lesions were medullary, the CM reached a pial surface in 6 of 7 patients, and 6 of 7 lesions were located on the right side. The mean age at presentation among the 13 patients in the nonsurgical group was 12.7 years, and the mean CM size was 10.6 mm. Seven of these patients had a prior history of radiation for tumor, and only 3 had lesions that reached a pial surface.

Conclusions. The management of brainstem CMs in children is influenced by multiple factors. The majority of patients received conservative management and tended to be asymptomatic with smaller lesions. Patients with larger lesions and direct pial contact, in whom symptoms arose at a younger age were more likely to undergo surgical management. A history of familial CM was also a predictor for receiving surgical treatment. No patients with a prior history of radiation therapy underwent surgery for CMs. The presence of multiple lesions seemed to have no impact on the type of management chosen. Patients who underwent surgery did suffer morbidity related to the procedure, and tended to improve clinically over time. Conservative management was associated with new deficits arising in children, some of which improved with time. Consideration of many clinical and radiological parameters is thus prudent when managing the care of children with brainstem CMs.

Childs Nerv Syst. DOI 10.1007/s00381-009-0977-5

The optimal surgical management of sylvian arachnoid cysts is debated. We present our experience in children who were treated endoscopically, focusing on the limits and complications of this approach.

Materials and methods: Seventeen children with a temporo- sylvian arachnoid cyst have been treated using a purely temporal endoscopic approach.

Results: In all but one case, the recognition of anatomical landmarks was obtained at the insertion of the endoscope. In one child, the orientation and opening of the basal cisterns were more difficult due to the thickness and opacity of the membranes. Nevertheless, it was possible to perform the cysto-cisternostomy endoscopically in all children with several stomies in 13. In one child, a venous bleeding occurred. There were no other intraoperative complications. There were no postoperative cerebrospinal fluid leaks. In two patients, a symptomatic subdural collection developed which required a transient subdural-peritoneal shunt. No subdural collection was noted on a delayed follow-up (mean, 23 months). Preoperative symptoms related to the mass effect exerted by the cyst resolved in all children. Two children presented a recurrence, 12 and 20 months after endoscopic surgery, respectively. At the redo-endoscopy, the stomies were found to be closed. Their reopening resulted in the disappearance of the symptoms.

Conclusions: An endoscopic approach can be used safely in the management of sylvian arachnoid cysts. An effective opening of the deep arachnoid membranes into the basal cisterns could be performed in all patients with the resolution of the preoperative symptoms. However, the long-term efficacy of the stoma needs to be assessed.

J Neurosurg Pediatrics 4:389–393, 2009. (DOI: 10.3171/2009.4.PEDS09210)

In recent years CSF shunt catheters impregnated with rifampicin and clindamycin have been introduced to the United Kingdom (UK) market. These catheters have been shown to be effective in vitro against cultures of Staphylococcus epidermidis. The authors used data collected by the UK Shunt Registry to assess the efficacy of antibiotic-impregnated catheters (AICs) against shunt infection by using a matched-pair study design.

Methods. The UK Shunt Registry contains data on nearly 33,000 CSF shunt-related procedures. The authors identified 1139 procedures in which impregnated catheters had been used, and accurate information was known about diagnosis, number of revisions, sex, and age in these cases. The database was ordered chronologically and searched forward and backward for cases with these same characteristics but involving conventional catheters. Matches were found for 994 procedures.

Results. Among the 994 procedures in which AICs had been used, 30 shunts were subsequently revised because of shunt infection. Among the 994 controls, 47 were subsequently revised for infection (p = 0.048, chi-square test).

Conclusions. The UK Shunt Registry does not collect data on causative organisms, and the surgeon is relied on entirely for the diagnosis of infection. However, with the large number of matched pairs evaluated, the authors attempted to reduce bias to a minimum. Their data suggest that AICs have the potential to significantly reduce shunt infections.

Pediatr Neurosurg 2009;45:262–270. DOI: 10.1159/000228984

Objectives: The aim of this study was to describe the characteristics of patients with a minor head injury (MHI) who were admitted to a pediatric emergency unit and to identify the clinical signs and symptoms that most reliably predict the need for cranial computed tomography (CCT) and hospital admission following MHI.

Methods: All patients were retrospectively evaluated according to age, gender, details of injury, presenting symptoms, physical examination findings, radiological investigations ordered and results, length of stay, outcome of the injury and hospitalization rates.

Results:The factors affecting indications for computed tomography and hospitalization were retrospectively analyzed in 916 patients – 585 males and 331 females, aged between 1month and 15 years (mean: 5.01 8 3.58 years), with MHI. A multivariate analysis revealed significant correlations between CCT abnormalities and Glasgow Coma Scale scores of 13 or 14, headache, posttraumatic amnesia, blurred vision, cephalohematomas, periorbital ecchymoses, otorrhea and abnormal neurological findings. CCT abnormalities were identified in 67 (19.8%) of the 338 CCT scans. Twenty of the 67 patients (29.9%) with CCT scan abnormality had no clinical signs. Of all cases, 125 (13.6%) were hospitalized, 617 (67.4%) were treated as outpatients, and 174 (19.0%) left the emergency department based on a personal decision.

Conclusion: Some clinical risk factors can be used as predictors of abnormalities in CCT scans following MHI, but the absence of such clinical findings does not exclude the possibility of intracranial injuries.