Does direct admission from an emergency department with on-site neurosurgical services facilitate time critical surgical intervention following a traumatic brain injury in children?

OBJECTIVES: To compare the proportion of trauma craniotomies performed within 4 hours of presentation to emergency departments (ED) with and without on-site neurosurgery. DESIGN: A retrospective cohort analysis of data collected prospectively between January 2005 and April 2010 from patients with traumatic brain injury who were admitted to the paediatric intensive care unit (PICU) following traumatic brain injury. METHODS: Times for admission to ED, PICU and theatre were obtained through analysis of prospectively collected data management systems. Emergency department admission to neurosurgical theatre lag time was calculated using Microsoft Excel. Statistical analysis was performed using R (version 2.11.0). Subjects. Fifty-seven cases were identified. Twenty patients were admitted directly from ED to an on-site neurosurgical unit. The remaining 37 were transferred from regional EDs. RESULTS: Thirty-one craniotomies were performed. Thirteen in-patients admitted directly to hospital with neurosurgery on site. Eighteen in patients admitted at the local hospital and then transferred to the neurosurgical unit. Thirteen of Thirty-one (42%) craniotomies were performed within 4 hours. In the on-site group 10 of 13 (77%) craniotomies were performed within 4 hours compared to 3 of 18 (17%) in those transferred from regional ED (p = 0.001232) (Fisher exact test). Eleven patients were transferred directly from ED to neurosurgical theatre for emergency craniotomies. Within this subgroup, seven patients came from the cohort of admissions to a hospital with on-site neurosurgery. The remaining four patients were transferred from regional ED. There were eight extradural haematomas, one subdural haematoma and two intraparenchymal haemorrhages. The mean time from ED presentation to theatre was 1.68 hours and 5.46 hours for the on-site and regional transfer groups, respectively. There were no mortalities. CONCLUSIONS: Forty-two per cent of trauma craniotomies are performed within 4 hours. However, presentation to an ED with on-site neurosurgical services significantly facilitates time critical surgery in children following a traumatic brain injury.

A case of paraganglioma of the hypoglossal nerve.

INTRODUCTION: Paragangliomas are rare tumours arising from the paraganglia of the autonomic nervous system. CASE REPORT: We present a case of a paraganglioma arising from the hypoglossal nerve and producing an unusual clinical picture at presentation. DISCUSSION: We supply radiological evidence of a paraganglioma originating from the hypoglossal nerve, and thus extend the evidence base for this rare site of origin. Our patient presented as an emergency with long tract neurological symptoms and progressive brainstem involvement. This presentation is not characteristic of paragangliomas in general, which usually have an indolent growth pattern and often demonstrate benign symptoms for a number of years prior to diagnosis. The location of a hypoglossal paraganglioma differs significantly from more common paragangliomas described in the neck and skull base, and this should inform the surgical approach undertaken.

Pattern, management and outcome of cervical spine injuries associated with head injuries in paediatric patients.

INTRODUCTION: This study examines the management and outcome of cervical spine injuries in children with head injuries, to assess the need for surgical treatment. MATERIAL AND METHODS: We performed a retrospective analysis (1995-2005) of 445 children admitted intubated and ventilated to the intensive care unit with head injuries. OUTCOME MEASURES: Frankel grade for spinal injuries and Glasgow Outcome Scale (GOS) for head injuries. RESULTS: Cervical spine injuries were detected in 11 patients (incidence 2.5%, mean age: 6.3 years, range: 21 months-15 years). The injuries were: C1/2 distraction: 2; C1/2 subluxation: 2; odontoid peg fracture with C1/2 dislocation and cord transection: 1; disruption of posterior longitudinal ligament at C2: 1; odontoid peg fracture with C2/3 distraction: 1; C2/3 subluxation: 1; C3 lamina fracture: 1; C3/4 facet fracture: 1; C6/7 fracture dislocation with cord transection: 1. One patient was managed operatively, ten patients nonoperatively, two with halo vests and eight with hard collars. There were three deaths (mortality 27%) associated with severe head injuries. At 6 months follow-up, two patients remained quadriplegic (Frankel Grade A), one of them ventilator dependent, one had residual motor function but of no practical use (Frankel Grade C), five had good spinal outcome (Frankel Grade E). Seven patients had good head injury outcomes (GOS 5), one remained disabled (GOS 3). CONCLUSION: Most children with cervical injury can be managed nonoperatively with good outcomes. Surgical management may be necessary in severe unstable injuries.

Incidence of vascular malformations in spontaneous intra-cerebral haemorrhage in children.

AIM: To assess the incidence of vascular malformations in children presenting with non-traumatic intra-cerebral haemorrhage and outline the need for radiological investigations. MATERIALS AND METHODS: Between 1993 and 2002, 26 children presented with spontaneous intra-cerebral haemorrhage at a mean age of 26 months (range 1-192 months). RESULTS: Twenty-two children had, as first treatment, surgical removal of the haematoma and any malformation found. One patient with no evidence of vascular malformation had conservative treatment, two had embolisation and one had stereotactic radiosurgery of arteriovenous malformations (AVMs). The diagnosis of vascular malformation was confirmed histologically and/or radiologically in 16 (61%) patients. Of these 16 patients, 7 were AVMs, 1 thrombosed middle cerebral artery (MCA) aneurysm, 1 cavernous angioma, 6 aggregates of abnormal vessels, 1 vein of Galen aneurysm. Pre-operatively, 12 patients had magnetic resonance imaging (MRI)/magnetic resonance angiography (MRA) and 7 were positive for vascular malformation (1 false positive) with no false negatives. Digital subtraction angiography (DSA) was performed pre-operatively in 7 patients, 4 were positive with no false negatives. There were no re-bleeds at the follow-up period. Five (19%) patients died from the haemorrhage, 7 (27%) had severe neurological deficit and 14 (54%) had no neurological deficit. Residual malformation after surgery requiring additional treatment was found in 3 (16%) patients. All patients with confirmed malformations were followed-up with DSA. CONCLUSION: MRI/MRA has high sensitivity and specificity in identifying vascular malformations in children presenting acutely with spontaneous intra-cerebral haemorrhage. This may prove useful when pre-operative DSA is not promptly available. After acute clot evacuation, there is high incidence of residual malformation and such patients should be followed-up with DSA.

Diastematomyelia in children: treatment outcome and natural history of associated syringomyelia.

OBJECTIVE: To quantify the long-term outcome of children with diastematomyelia and the implication of syringomyelia in the natural history. MATERIALS: Retrospective study of 17 children (nine girls and eight boys) with diastematomyelia operated during 1989-2004. Mean age at diagnosis was 3.4 years (range 5 days-12 years), mean follow-up was 5 years; 14 had excision of spur and cord untethering, 3 had excision of spur alone. RESULTS: The bony spur was in the lumbar region in 12 and thoracic in 5 patients. Syringomyelia was present in eight (47%), associated with bony spur between L1 and 4 (p=0.088), spina bifida occulta in ten (58.8%), and spinal lipoma in one (6%). Preoperative Necker Enfants Malades (NEM) scores were 17 in eight patients, 16 in four, 15 in three, 13 in one, and 12 in one patient. Presenting neurological deficits were motor in eight, sensory deficits in three, and anal incontinence in one patient. There was improvement of NEM scores postoperatively in five patients only, but still with residual deficit. Repeat spur excision and cord untethering was performed in three patients for neurological deterioration 1-4 years after first operation. On postoperative MRI scans syringomyelia remained unchanged in all eight patients. There were one skin infection, one transient motor deterioration, and one patient with sensory deficit after surgery. CONCLUSION: Prophylactic operations were associated with the best clinical outcome. Despite improvement, all patients with established preoperative deficit still had residual neurological deficits at their last follow-up. The associated syringomyelia remained unchanged after surgery, indicating that it does not contribute to the neurological syndrome.

Outcome of children with posterior fossa medulloblastoma: a single institution experience over the decade 1994-2003.

AIM: While the impact of radiotherapy in the management of medulloblastoma was recognised, the introduction of chemotherapy was investigated in clinical trials and shown to confer an additional advantage. We reviewed the outcome of a series of consecutive patients to assess the impact in a population-based clinical establishment. MATERIALS AND METHODS: A series of 38 children treated for medulloblastoma at Birmingham Children's Hospital between 1994 and 2003 was analysed. The effect of surgery, radiotherapy, chemotherapy and metastasis on survival was analysed. RESULTS: The overall 5-year survival rate was 61.4% for the 36 patients who had resective surgery, while 2 patients had biopsy only and died within a few months. There was no operative mortality. The incidence of hydrocephalus needing permanent shunting was higher in the first 3 years of life (p = 0.007, chi-square). The 5-year survival rate of patients with total and sub-total excision of medulloblastoma was 61.1% and 61.8%, respectively. The 5-year survival rate of patients older than 3 years was 73.4% and for patients under 3 years was 36.3% (p = 0.007, log rank). Metastases at presentation did not influence survival. All deaths occurred in the first 32 months. CONCLUSION: The contribution of chemotherapy in the improvement of the overall survival appears more evident in children younger than 3 years or presenting with metastases. The absence of significant difference in survival between patients with total or sub-total excision of medulloblastoma supports the view that total excision of medulloblastoma can be avoided when the risk for potential intra-operative damage and consequent neurological deficits is high.

Dissemination of fat in CSF: a common finding following translabyrinthine acoustic neuroma surgery*.

OBJECTIVES: Following translabyrinthine craniotomy the temporal bone defect is commonly obliterated using a free autologous fat graft. In this series the dura was put back in place but not closed primarily. As the fat graft remains in direct contact with the cerebro spinal fluid (CSF) there is potential for dispersal of fat within the CSF space. This paper aims to determine the frequency of such CSF fat dissemination and its clinical significance. DESIGN: A retrospective review of translabyrinthine acoustic neuroma removal with free fat autograft obliteration of the temporal bone defect between the years 1997 and 2000. SETTING: Tertiary referral oto-neurosurgical centre. Postoperative magnetic resonance (MR) imaging. PARTICIPANTS: All translabyrinthine patients who had postoperative MR imaging were included. Twenty-six cases were identified. Age range was 13-70 years. Fourteen were male patients. MAIN OUTCOME MEASURES: Evidence of CSF fat dissemination on MR and patients' clinical findings. RESULTS: Twenty-two of the 26 scans (85%) demonstrated evidence of fat dissemination into the subarachnoid CSF spaces in the form of microemboli. The cerebellopontine angle was the most common site involved. No evidence of ventricular dilation or any other abnormality was noted. There was no relationship between the presence or extent of fat microembolization and the patients' clinical course. CONCLUSIONS: This study suggests that free fat placed in temporal bone defects commonly migrate into the subarachnoid space and subsequently move around in these spaces. This is not associated with any complications such as hydrocephalus, meningitis or prolonged postoperative headache.

Cranioplasty in children.

OBJECTIVE: The objective was to assess the outcome and complications associated with different cranioplasty implant materials in children. MATERIALS AND METHODS: A retrospective review was conducted of 28 consecutive cranioplasties carried out on 24 children between 1994 and 2001 (age range, 9 months to 15 years; minimum follow-up 18 months). The indications were: defect from previous craniectomy for trauma, tumour, infection or evacuation of haematoma (n=21), intradiploic dermoid cysts (n=2), growing fractures (n=4) and residual bony defect following craniofacial reconstruction (n=1). The materials used were: patient's craniectomised bone flap (n=16), split calvarial graft (n=8), acrylic (n=3) and titanium (n=1). All patients were assessed for bony fixation, cosmesis, wound healing and flap infection. RESULTS: There was no mortality and 18% morbidity (n=5: 3 infected flaps, 1 sterile wound dehiscence and 1 sterile wound discharge; overall infection rate 10%). Out of the 14 patients who had their own craniectomised bone flaps implanted initially, 3 became infected (2 in patients with bilateral defects) necessitating flap removal. Two of these were successfully re-implanted. No donor or recipient bone flap complications were seen in the 8 split calvarial grafts, wound discharge was seen in 1, requiring wound toilet. No complications were seen with acrylic or titanium cranioplasties. CONCLUSION: In this series, the use of the patients' own craniectomised flap had a low infection rate, and was mainly seen in patients who had bilateral flaps re-implanted soon after removal. There were no complications arising from the use of split calvarial and allograft material. Use of autologous implant material should be preferred whenever possible due to obvious resource and biological advantages, and can even be re-implanted if infected.

Stereotactic biopsy of brain tumours in the paediatric population.

OBJECTIVE: Our objective was to establish the role of stereotactic neurosurgical techniques in the management of brain tumours in children. MATERIALS AND METHODS: A retrospective analysis was conducted of all stereotactic procedures performed in a single centre between 1996 and 2001. The success rates of achieving histologic diagnosis and a correlation between radiologic and histologic diagnosis were examined. RESULTS: There were 7 boys and 7 girls with a mean age of 9.1 years (range: 4-15). Under general anaesthetic 15 procedures were performed in 14 patients: 12 diagnostic and 3 therapeutic; 10 with CT and 5 with MRI guidance; 10 lesions were supratentorial and 4 were in the pons. A definitive histologic diagnosis was established in 10 of the 12 cases (diagnostic yield 83%). The pre-operative radiological diagnosis was accurate for tumour type in only 75% of the cases. In 3 patients cyst aspiration was attempted: post-operatively the cyst size was decreased in 2 and unchanged in 1. Seizures and acute confusion following biopsy of a thalamic tumour occurred in 1 patient. Post-operative scans were performed in 7 patients and in 2 we noted small, clinically insignificant, haemorrhages at the biopsy site. There was no mortality and morbidity was 6.6%. CONCLUSIONS: This small series confirms that stereotactic procedures in children are safe, well tolerated, with a high diagnostic yield, which could be improved with the use of intraoperative histopathological examination.

Spinal sagittal malalignment following surgery for primary intramedullary tumours in children.

BACKGROUND/OBJECTIVE: As prior studies analysed predictive factors for various post-laminectomy spinal deformities in mixed spinal regions, age groups or pathologies, their validity and conclusions were unclear. The objective of this study was to determine predictive factors for worsened cervical or thoracic spinal sagittal alignment following laminectomy or laminotomy for primary intramedullary spinal cord tumours in children. METHODS: In this retrospective study, patients treated between 1980 and 1998 were reviewed. Changes in spinal alignment at the last follow-up compared to the pre-operative state were studied. Factors analysed were age, pre-operative spinal alignment, procedure types (laminectomy or laminoplasty), number of laminae operated, surgery of C2 or T1 laminae, histological grade, presence of post-operative neurological deficit and post-operative radiotherapy. RESULTS: There were 27 patients. The mean age was 5.6 years (range 1.3-14.0 years), and the mean duration of follow-up was 3.7 years (range 0.075-9.9 years). In the cervical-cervicothoracic surgical group (n = 12), alignment worsened post-operatively in 3 patients. The number of laminae operated upon had a statistically significant impact on the development of post-operative kyphosis (p = 0.07). In the thoracic-thoracolumbar surgical group (n = 15), alignment worsened in 9 patients. Procedure types were statistically significantly different, with laminectomy associated with an increased risk of post-operative kyphosis (p = 0.01). All 5 patients who had spinal fusion for worsened post-operative alignment were in the thoracic-thoracolumbar group; no patients in the cervical-cervicothoracic group required spinal fusion (p = 0.047). Other predictive factors did not reach statistical significance (p > 0.05). CONCLUSIONS: Worsened spinal sagittal alignment following laminectomy or laminoplasty and the need for spinal fusion is more common in the thoracic-thoracolumbar region than in the cervical-cervicothoracic region. In the cervical-cervicothoracic region, operation on a greater number of laminae tends to increase the risk of worsened alignment. In the thoracic-thoracolumbar region, laminectomy is associated with worsened alignment, while laminoplasty reduces this risk; also, pre-operative kyphotic deformity tends to increase the risk of worsened alignment post-operatively.

Outcome of surgical treatment for subdural fluid collections in infants.

We reviewed retrospectively the management of 47 infants with subdural collections at the Birmingham Children's Hospital. Of those patients who had needle aspiration as their initial treatment 42% required some form of further treatment and 25% were complicated by infection of the subdural collection. Of those patients treated with burr hole evacuation or with observation alone, 78 and 73%, respectively, required no further procedures. However, 17% of those who had burr holes as their initial treatment developed post-operative infected collections. Of those who had subdural-peritoneal shunt as initial or subsequent treatment, none required further procedures to treat the subdural collections. No infections were noted following shunting. There was no statistically significant difference in overall clinical outcome at last follow-up between the different treatment groups. We conclude that needle aspirations should be avoided due to high infection risk, and that observation alone can be sufficient in the absence of intracranial hypertension, as the condition may be self-limiting. In cases requiring surgery, it should be borne in mind that burr hole evacuation has a higher infection risk, whereas subdural shunting has the additional need for removal of the device if the parents and surgeon decide accordingly.

The treatment of infantile hydrocephalus: "differential-pressure" or "flow-control" valves. A pilot study.

The choice of shunt valve in the treatment of hydrocephalus in children remains controversial. We embarked on a pilot study to determine the differences in outcome between differential-pressure and flow-regulating valves. Prospective data collected on 50 consecutive first-time shunt insertions, performed between June 1993 to June 1996, was analysed. Children with tumour-related hydrocephalus and Dandy-Walker malformations as well as children who had external ventricular drainage prior to definitive shunt insertion were excluded from the study. The defining event was the first complication necessitating surgery, including obstruction, over-drainage and infection. Of the 50 children (31 males), 23 had differential pressure (medium-pressure) and 27 had Delta (performance level 2) valves inserted. The mean age at shunt insertion was 26.4 months. The mean follow-up was 53.8 months. The overall cumulative shunt survival at 5 years was 58.6% for the differential pressure and 58.7% for the Delta valves. The mean shunt life was 37.1 months for the differential pressure group and 34.6 months for the Delta group. This difference was not statistically significant (P=0.72, t-test). Both valves had a similar outcome with respect to obstruction (including proximal, valve, distal). The main differences between the two valves were with respect to the incidence of over-drainage and infection. Amongst the differential pressure valves, there were 4 instances of overdrainage (3 slit-ventricle syndrome, 1 bilateral subdural collection)--all occurring within the first 36 months. The Delta valve group had only one instance of over-drainage (bilateral subdural collection). There were no infections in the differential pressure valve group, whereas 3 of the Delta valve shunts got infected, all within the first month. Whereas both shunt types seemed to have a similar overall survival, there was a relatively higher incidence of over-drainage amongst the differential pressure valves. The Delta valves, on the other hand, had higher rates of infection. Similar studies with larger numbers could suggest whether the choice of shunt type will ultimately have to be a compromise accepting one or the other complication.

Spinal teratoma: is there a place for adjuvant treatment? Two cases and a review of the literature.

Spinal teratomas are rare intradural spinal tumours, commonly of benign histological profile. The main treatment remains surgical excision which often is incomplete as the tumour is frequently intimately related to surrounding nerve roots and adjacent spinal cord. The value of adjuvant treatment in the form of radiotherapy has not been clearly identified. We report two patients with spinal teratomas in the lower thoracic and conus region, who were treated with surgical excision and did not receive radiotherapy. One of the tumours recurred at 38 months following surgical excision and required a second operation. We review in addition another 20 patients reported in the literature with such tumours. With a mean follow-up of 25 months a local recurrence rate of 10% was observed, the same in both total and subtotal excision groups. No deaths were reported. Analysis of cumulative survival from surgery to treatment failure demonstrated that recurrence occurs late, verifying a slow biological progression of this tumour type. Although no reliable information of the effect of radiotherapy can be obtained, it is difficult to see how radiotherapy could have an impact on such a slow growing tumour. Initial treatment of choice remains surgical excision. If the teratoma shows any malignant histological features or germ cell elements radiotherapy should be employed after surgical excision, even if apparently totally excised. In the presence of benign histology it would seem appropriate to avoid radiotherapy after initial surgery. In case of tumour recurrence or progression to explore the possibility of further surgery first, before considering radiotherapy which even then may have doubtful efficacy.

Is Ollier's disease an understaging of Maffucci's syndrome?

Ollier's disease and Maffucci's syndrome are similar multiple enchondromatous conditions. Other co-existing pathologies, particularly other primary malignancies, have been described sporadically in both conditions but more so in Maffucci's syndrome. Maffucci's syndrome is distinguished from Ollier's disease by the presence of haemangiomas in the former. In this report, a patient believed to have Ollier's disease for 44 years was subsequently found to have large splenic haemangiomas on magnetic resonance imaging (MRI). In the light of this, we recommend that any patient diagnosed with Ollier's disease to have total body MRI to search for haemangiomas that will alter the diagnosis to Maffucci's syndrome and hence the prognosis. MRI also screens for the presence of other associated malignancies.

Computer simulation of a neurosurgical operation: craniotomy for hypothalamic hamartoma.

Although magnetic resonance imaging has revolutionised the management of intracranial lesions with improved visualisation of anatomical structures, it only produces two-dimensional images, from which the clinician has to extrapolate a three-dimensional interpretation. Several approaches can be used to create 3D images; the discipline of image segmentation has encompassed a number of these techniques. Such techniques allow the clinician to delineate areas of interest. The resulting computer-generated outlines can be reconstructed in a three-dimensional arrangement. Although a plethora of "generic" segmentation techniques exist, we have developed a refined form, dependent on general and particular properties of the anatomical structures under investigation. High-contrast structures such as the ventricles and external surface of the head are found by using a localised adaptive thresholding technique. Less definable structures, with poor or nonexistent signal change across neighbouring structures, such as brain stem or pituitary, are found by applying an "energy minimisation"-based technique. To demonstrate the techniques we used the example of an 8-year-old boy with uncontrolled gelastic seizures due to a hypothalamic hamartoma, who is being considered for surgery. We were able to demonstrate the anatomical relationships between the hypothalamic hamartoma and adjacent structures such as optic chiasm, brain stem and ventricular system. We were subsequently able to create a video, reproducing the stages of craniotomy for excision of this tumour. By creating true 3D objects, we were able at any stage of the simulation to visualise structures situated contralaterally to the approaching surgical dissector. These 3D representations of the structures can be either invisible or opaque, in order to afford 3D localisation as the "virtual" surgical dissection proceeds. The clinical application of such techniques will enable surgeons to improve their understanding of anatomical relations of intracranial lesions and has obvious implications in image-guided surgery.

Paediatric meningeal tumours.

We review our experience of meningeal tumours in patients under 16 years who were treated between 1957 and 1993. These were 16 with meningiomas (median age 12 years) and 5 with poorly differentiated malignant meningeal tumours (median age 3 years). The incidence of meningeal tumours in this period was 1.62% of all CNS tumours. There were 19 supratentorial tumours (5 intraventricular), 1 tentorial and 1 cervical. Surgical excision was complete in 12 patients and incomplete in 6; in 2 patients a biopsy only was undertaken. The remaining patient had radiological diagnosis only. All 5 patients in the group with malignant poorly differentiated tumours died (median survival 5 months), confirming the aggressive nature of these lesions. Of the 16 patients with meningiomas, 4 died during followup but 11 of the 12 meningioma patients remaining alive had complete resections. There is a strong tendency for paediatric meningeal tumours to have a supratentorial origin and intraventricular location. The female preponderance found in adults is not evident in children. Incomplete surgical excision or focal neurological deficit at presentation was associated with poor outcome.

The value of colour Doppler imaging in assessing flow through ventriculo-peritoneal shunts.

So far, Doppler ultrasonography has had little application in paediatric neurosurgery. The incidental observation of normally invisible CSF flow from the peritoneal end of a ventriculo-peritoneal (V-P) shunt on colour Doppler during a conventional abdominal ultrasound examination in one of our patients suggested that colour Doppler imaging might be of potential interest. Using a 10-5 MHz broad-band linear array transducer, conventional 2D and Doppler (spectral and colour-coded) ultrasonography was performed in 17 patients with V-P shunts, who were aged 3 months to 12 years. In all, 20 examinations were performed, because 2 patients had repeat examinations before and after shunt revision. In 13 examinations (65%) CSF flow was identified through the shunt tube. Flow velocities between 5 and 7 cm/s were measured. No flow was seen in 7 examinations (35%), 3 of which (15%) were performed before revisions for a blocked shunt. Further in vitro studies with simulated shunt/ventricular system model demonstrated that although clear CSF is not ultrasonically visible, the presence of particulate matter, such as choroid plexus debris, can generate a satisfactory Doppler signal with the probe insonating over the length of the tubing. In the presence of clear CSF, turbulence generated at junction points of the shunt system or at the exit of the peritoneal tube can be visualised well with Doppler ultrasonography, presumably due to generation of microbubbles. The clinical implications for the management of shunt obstruction are discussed.