Darach Crimmins

Toward reducing shunt placement rates in patients with myelomeningocele

OBJECT The prevalence of shunt-dependent hydrocephalus in patients with myelomeningocele has been reported to be in the region of 85%, and shunt-related complications are a significant cause of morbidity and mortality in these patients. Since 1997 the authors have adopted a stringent policy with respect to shunt placement in patients with myelomeningocele, reserving this treatment for those with symptomatic hydrocephalus, severe ventricular dilation at the time of presentation, and/or unequivocal progressive ventriculomegaly after primary closure. They report their experience. METHODS The authors reviewed all cases of myelomeningocele involving patients who presented to their institution over a 10-year period. They excluded cases in which the primary closure was carried out at another institution or in which there was not at least 12 months of clinical and imaging follow-up. Data regarding shunt insertion shunt-related complications, and clinical outcome were obtained from a review of the clinical records and analyzed. RESULTS Fifty-four cases satisfied the inclusion criteria for this study. Shunt insertion was performed in 28 of these cases (51.9%). CONCLUSIONS Applying more stringent guidelines for shunt placement, permitting moderate ventricular dilation, and accepting some mild increase in ventricular size after myelomeningocele closure has resulted in a reduced rate of shunt placement compared with previous series. The rate is comparable to that reported following in utero closure of myelomeningocele.

Patients with autosomal-recessive osteopetrosis presenting with hydrocephalus and hindbrain posterior fossa crowding.

Osteopetrosis is a heterogeneous group of disorders characterized by abnormal bone sclerosis. As a result, patients often require input regarding various neurological complications. Although autosomal-recessive osteopetrosis has been associated with hydrocephalus, it has not been linked to hindbrain abnormalities. The authors present 3 cases of auto-somal-recessive osteopetrosis in patients who presented with hydrocephalus. In each of these patients, cerebrospinal fluid diversion procedures were required and hindbrain compression developed. To date, only 1 patient has needed craniocervical decompression due to symptomatic brainstem compression.

Efficacy of ventricular access devices in the treatment of neonatal intraventricular haemorrhage

Background Post Haemorrhagic Hydrocephalus (PHH) secondary to Neonatal Intraventricular Haemorrhage (IVH) is the commonest cause of infantile hydrocephalus. The presence of ventricular blood, underdeveloped immune systems and thin, friable skin preclude shunting as a primary intervention. Studies show that serial lumbar punctures, medical management and ventricular taps have no discernible effect on outcome. This study attempts to more clearly elucidate the role and efficacy of ventricular access devices (VAD) in the treatment of PHH. The aims were to determine the complication rate, the use of the VAD and the number of patients with VAD who later required shunting.

Occurrence and distribution of pilomyxoid astrocytoma

Abstract Purpose. To know the occurrence and distribution of Pilomyxoid Astrocytomas amongst tumours previously diagnosed histologically as Pilocytic Astrocytoma and to assess the clinical impact of this new entity. Methods. Retrospective Diagnostic review of all cases histologically diagnosed as WHO Grade I Astrocytoma at a single Neurosurgical unit between 1990 and 2003. Results. Of a total of 91 cases identified, 9 were found to have Pilomyxoid histology. Of these, 8 were children (mean age 3.33 years) and 1 adult. 6 tumours were hypothalamochiasmatic in location. The clinical course of Pilomyxoid tumours was aggressive marked by maturation, multiple recurrences and disease control was rarely achieved with single treatment modality as opposed to typical pilocytics. The overall survival of the pilomyxoid group was not statistically different from the pilocytic tumours. Conclusions. Encompassing all age-groups and locations, Pilomyxoid Astrocytomas constitute about 10% of all tumours previously diagnosed as Pilocytic Astrocytoma. Nearly two-thirds are hypothalamo-chiasmatic in location. Knowledge of this entity is essential for appropriate aggressive treatment and follow-up.

Extradural haematomas in children - a 10-year review

Extradural haematomas are a significant consequence of head injuries in children. The aim of this study was to evaluate the demographics, symptoms and signs, management and outcome of patients less than 18 years of age with extradural haematomas in our unit. We also specifically looked at repeat imaging performed, indications for this and its effect on further management. No previous reviews have included this. Fifty-six patients were identified from 01/01/1997 to 01/01/2007 for inclusion in this study. Their imaging was then reviewed as were the case notes. Of the patients studied, 70% were male. The average age was 10 years and 2 months with an average length of stay of one week. The commonest mechanisms of injury were a fall from height and an accident involving a bike. Presenting symptoms were documented in 40% of cases. 32% of patients had associated skull fractures. Six patients had other injuries, including long bone fractures and maxillofacial injuries. Glasgow Coma Scale was generally better on admission than pre-operatively and post-operatively was generally better than prior to surgery. Eight patients had neurological signs on admission, 11 had pre-operatively, and nine had post-operatively. 71% underwent a craniotomy with evacuation of the haematoma. Complications were reported in 16% with no mortality. 66% were seen in a neurosurgical clinic, with 46% seen in a Paediatric Head Injury Clinic after discharge. 66% had further imaging after their initial scan of which 52% had no clinical indication. Eight patients were operated on following re-imaging. Most extradural haematomas in children are caused by falls or vehicle accidents. The majority are treated surgically and do well. Indications for further scanning are often not present and in most, management is unchanged. The follow up of these patients also appears to be suboptimal.

British Paediatric Neurosurgery–A time for change?

Paediatric Neurosurgery in the UK and Eire has progressively evolved as a sub-specialty over the last 20 years. The British Paediatric Neurosurgery Group was founded in 1988 and formally recognized by the Society of British Neurological Surgeons (SBNS), ‘to promote and encourage the development of paediatric neurosurgery’. In 1998 the SBNS published Safe Paediatric Neurosurgery which set out the minimum requirements for paediatric neurosurgery. In response to the Kennedy Report and the Report of the Paediatric Forum of the Royal College of Surgeons of England (Children’s Surgery – A First Class Service) the Council of the SBNS convened a short life working party to review and update this document resulting in Safe Paediatric Neurosurgery 2001. Seven years have now elapsed since the publication of Safe Paediatric Neurosurgery 2001 and a number of its recommendations remain unfulfilled. Additionally, over the intervening period additional new pressures have come to bear on the delivery of small volume, high risk, high cost specialties which raise questions on how best to cost-effectively deliver these services in the future. The lack of a national strategy for paediatric neurosurgery coupled with financial concerns over the viability of local paediatric neurosurgical services, concerns over the volume of work required for training and revalidation, the effect of the European Working Time Regulation (EWTR) on man-power issues and the need for equity of access to a high quality service lead to the conclusion that it is now timely to reconsider how best to offer paediatric neurosurgical services within a national framework. The rationalization of specialist surgical services is not new and not limited to the UK. In France new legislation (Cross H, Great Ormond Street Hospital, London, personal communication, March 2007) outlines the minimum requirements for a unit undertaking paediatric neurosurgery with a view to restricting paediatric neurosurgical services to a limited number of units. In Scotland, the neuroscience group contributing to the Kerr Report suggested that there should be a single paediatric neurosurgical centre for Scotland and that it should be on the same site as an adult neurosurgical service. This continues to be the view of the Neuroscience Implementation Group whose work is still in progress and no formal decision has been reached. When practicable, the colocation of paediatric and adult neurosurgical services has many obvious advantages – not least being the cross fertilization of ideas and the best use of scarce resources and personnel. Paediatric cardiac surgery and paediatric oncology in the UK are presently going through similar attempts to rationalize services. In fact, the Paediatric and Congenital Cardiac Services Review (PCCSR) recommended that there be larger units and a consensus statement is in preparation. Interestingly, approximately the same number of paediatric cardiac procedures are performed each year (4000) as in paediatric neurosurgery. The expected recommendation is that there should be a significant reduction in the number of centres – with the new centres being manned by 4 or 5 surgeons. The appointment of more surgeons to the current centres is not considered a viable solution ‘as the number of cases in the UK is relatively fixed and each surgeon needs a minimum level of operating to maintain their skills’.

Suprasellar pilocytic astrocytoma: one national centre's experience.

IntroductionPilocytic astrocytomas in the supratentorial compartment make up 20 % of all brain tumours in children with only 5 % of these arising in the suprasellar region. Optic pathway gliomas or suprasellar gliomas are often seen in neurofibromatosis type 1 (NF1) patients. Given their location, suprasellar pilocytic astrocytomas are challenging to manage surgically with high morbidity rates from surgical resection. We assess our cohort of patients with suprasellar pilocytic astrocytoma and document our experience.MethodA retrospective review of patients diagnosed with suprasellar glioma between 2000–October 2012. We included patients diagnosed with optic pathway glioma based on radiological features (with or without biopsy) and those who had a biopsy confirming pilocytic astrocytoma.ResultsFifty-three patients included (sporadic tumours 24 and NF1 related 29). Fifteen sporadic and four NF1 patients were biopsied. Twelve sporadic and 13 NF1 patients were initially treated with chemotherapy while only 1 patient had radiotherapy initially. Progression was noted in 58 % of the sporadic group and 24 % of the NF1 group. The only significant factor for progression was NF1 status (p = 0.026).ConclusionManagement should be guided by individual patient circumstance. In our cohort, chemotherapy did not significantly improve progression free survival; however, NF1 status significantly correlated with the decreased progression.

Diffuse hemispheric dysembryoplastic neuroepithelial tumor: a new radiological variant associated with early-onset severe epilepsy

The authors describe the clinical and radiological features in 3 children with a diffuse hemispheric dysembryoplastic neuroepithelial tumor (DNET) presenting with severe epilepsy and a previously unreported and characteristic MR imaging appearance. The DNET is a well-recognized cause of focal epilepsy, usually with a very good response to resection. These tumors are usually intracortical, and most commonly arise in the temporal lobe or frontal lobes. Radiologically they are usually sharply demarcated, and show little contrast enhancement. Three children (2 boys and 1 girl) presented at 14, 17, and 22 months of age with epileptic seizures. The seizures were focal motor or complex focal. One patient had epileptic spasms. The response to antiepileptic drug therapy was poor. Motor and cognitive development was delayed in all patients. One patient developed a severe epileptic encephalopathy, with regression of motor and cognitive skills. Her electroencephalogram obtained at that time showed hypsarhythmia. Admission MR imaging showed a diffuse unilateral abnormality involving frontal, temporal, and parietal lobes with little or no mass effect. There was involvement of both gray and white matter, with a striking sparing of the internal capsule in spite of apparent tumor throughout the basal ganglia and thalamus. In 2 patients there was prominent expansion of cortical gyri by tumor. In 1 child the initial radiological diagnosis was a middle cerebral artery infarct. On subsequent review the radiological diagnosis was thought to be low-grade glioma in all patients. The first patient underwent 2 limited resections involving the temporal lobe. He has continued to have poorly controlled seizures and severe behavioral and cognitive problems. The other patients had subtotal resection to the level of the internal capsule. One patient is currently seizure free 24 months postsurgery, but remains cognitively impaired. The patient in Case 3 is having some seizures 3.5 years postsurgery and remains hemiplegic, but the regression has reversed and she is making steady developmental progress. The pathological specimens showed the typical features of a DNET in all cases. This striking radiological pattern has not previously been described as a feature of a DNET. Recognition of this radiological pattern in young children with epilepsy will allow early consideration for resection, which may lead to improved long-term cognitive outcome.

Neurologist vs the neurosurgeons: who is the NICEst? The medical management of the neurosurgical patient with seizures.

Seizures and epilepsy are a relatively common occurrence in the neurosurgical patient. Neurosurgeons are often involved in the medical management utilising anti-epileptic drugs (AEDs). There is a distinct lack of contemporary literature in relation to management of seizures/epilepsy in the neurosurgical patient, in particular, for the newer AEDs. In the UK, clinical practice guidelines have been issued from both the National Institute for Health and Clinical Excellence (NICE) and Scottish Intercollegiate Guidelines Network (SIGN) in relation to epilepsy in primary and secondary care. We sought to determine current management practice for neurosurgical patients with epilepsy/seizures. The relevance of the issued guidelines was examined within the neurosurgical setting. An audit by telephone survey was conducted in Neurosurgical and Neurology units in the UK. Respondents were asked about the management of patients in two clinical scenarios. We received 25 responses from the neurosurgical and 22 responses from the neurology communities. Management of the patient scenarios is described and is further considered in relation to the published guidelines. There was considerable disparity between the guidelines and the management strategies pursued by both groups. We conclude that the standard of treatment is sub-optimal in many cases. The guidelines have not had a significant influence and are not felt to be strictly relevant within the neurosurgical setting. The development of guidelines relevant to the neurosurgical setting is proposed. Further research within this field and investment in education for neurosurgeons relating to AED therapy is advocated. The neurologists responses were more closely aligned to the guidelines and so they were deemed the ‘NICEst’.

ETV as a last resort

IntroductionThe field of neuroendoscopy is rapidly expanding with increasing indications for endoscopic third ventriculostomy (ETV).DiscussionAs a treatment for hydrocephalus, ETV has the advantage of providing a more physiological cerebrospinal fluid diversion without shunt hardware which reduces the risk of recurrent infection and malfunction. The success rate of ETV has been increasing with decreasing morbidity and mortality.ConclusionOriginally, ETV was indicated for cases of obstructive hydrocephalus, however the indications are expanding. To highlight this, we present a small series of cases were ETV is not traditionally indicated and was a treatment of last choice.