Intracranial monodermal teratoma presenting with growing teratoma syndrome.

Intracranial teratomas are rare. We report a case of a purely monodermal teratoma manifesting as intracranial growing teratoma syndrome. To the best of our knowledge, this is the first report of such nature in the literature.

The current role of decompressive craniectomy for severe traumatic brain injury.

There is little doubt that decompressive craniectomy can reduce mortality however, the results of a recent study has provided more evidence to inform the debate regarding clinical and ethical concerns that it merely converts death into survival with severe disability or in a vegetative state. The recently published RESCUEicp trial compared last-tier secondary decompressive craniectomy with continued medical management for refractory intracranial hypertension after severe traumatic brain injury. Patients were randomly assigned to decompressive craniectomy with medical therapy or to receive continued medical therapy with the option of adding barbiturates. The results of the study support the findings of the stroke studies in that the reduction in mortality was almost directly translatable into survival with either severe disability or in a vegetative state. The question remains as to whether there is a subset of patients who obtain benefit from surgical decompression and it is in this regard that the use of observational cohort studies and sophisticated outcome prediction models may be of use. Comparing the percentage prediction with the observed long outcome provides an objective assessment of the most likely outcome can be obtained for patients thought to require surgical intervention. Whilst there will always be limitations when using this type of data they may help prompt appropriate patient-centred discussions regarding realistic outcome expectations. A broader debate is also needed regarding use of a medical intervention that may leave a person in a condition that they may feel to be unacceptable and also places a considerable burden on society.

Reconsidering the role of decompressive craniectomy for neurological emergencies.

OBJECTIVE: There is little doubt that decompressive craniectomy can reduce mortality. However, there is concern that any reduction in mortality comes at an increase in the number of survivors with severe neurological disability. METHOD: Over the past decade there have been several randomised controlled trials comparing surgical decompression with standard medical therapy in the context of ischaemic stroke and severe traumatic brain injury. The results of each trial are evaluated. RESULTS: There is now unequivocal evidence that a decompressive craniectomy reduces mortality in the context of "malignant" middle infarction and following severe traumatic brain injury. However, it has only been possible to demonstrate an improvement in outcome by categorizing a mRS of 4 and upper severe disability as favourable outcome. This is contentious and an alternative interpretation is that surgical decompression reduces mortality but exposes a patient to a greater risk of survival with severe disability. CONCLUSION: It would appear unlikely that further randomised controlled trials will be possible given the significant reduction in mortality achieved by surgical decompression. It may be that observational cohort studies and outcome prediction models may provide data to determine those patients most likely to benefit from surgical decompression.

Cerebral metastases from Merkel cell carcinoma: long-term survival.

Merkel cell carcinoma is a rare primary cutaneous neuroendocrine tumour that is locally aggressive. In most cases the primary treatment is local surgical excision; however, there is a high incidence recurrence both local and distant. Cerebral metastases from Merkel cell carcinoma are extremely uncommon with only 12 cases published in the literature. This case is particularly unusual in that, not only was no established primary lesion identified, but also the patient has survived for 10 years following initial diagnosis and for 9 years following excision of a single brain metastasis.

Malignant cerebral swelling following cranioplasty.

Over the past few years there have been a number of case reports and small cohort studies that have described so called "malignant" cerebral swelling following an uneventful cranioplasty procedure. The pathophysiology remains to be established however it has been suggested that it may be related to a combination of failure of autoregulation and the use of closed vacuum suction drainage. The current study presents three further patients who had had a decompressive hemicraniectomy for ischaemic stroke. If decompressive craniectomy is utilised in the management of neurological emergencies, close attention and wider reporting of this type of complication is required not only to focus attention on possible management strategies, but also to determine which patients are at most risk of this devastating complication.

Reconsidering the role of hypothermia in management of severe traumatic brain injury.

Over the past two decades there has been considerable interest in the use of hypothermia in the management of severe traumatic brain injury. However despite promising experimental evidence, results from clinical studies have failed to demonstrate benefit. Indeed recent studies have shown a tendency to worse outcomes in those patients randomised to therapeutic hypothermia. In this narrative review the pathophysiological rationale behind hypothermia and the clinical evidence for efficacy are examined. There would still appear to be a role for hypothermia in the management of intractable intracranial hypertension. However optimising therapeutic time frames and better management of strategies for complications will be required if experimental evidence for neuroprotection is to be translated into clinical benefit.

The role of evidence based medicine in neurotrauma.

The introduction of evidence based medicine de-emphasised clinical experience and so-called "background information" and stressed the importance of evidence gained from clinical research when making clinical decisions. For many years randomised controlled trials have been seen to be the only way to advance clinical practice, however, applying this methodology in the context of severe trauma can be problematic. In addition, it is increasingly recognised that considerable clinical experience is required in order to critically evaluate the quality of the evidence and the validity of the conclusions as presented. A contemporary example is seen when considering the role of decompressive craniectomy in the management of neurotrauma. Although there is a considerable amount of evidence available attesting to the efficacy of the procedure, considerable clinical expertise is required in order to properly interpret the results of these studies and the implications for clinical practice. Given these limitations the time may have come for a redesign of the traditional pyramid of evidence, to a model that re-emphasises the importance of "background information" such as pathophysiology and acknowledges the role of clinical experience such that the evidence can be critically evaluated in its appropriate context and the subsequent implications for clinical practice be clearly and objectively defined.

Decompressive craniectomy--a narrative review and discussion.

There continues to be considerable amount of interest in decompressive craniectomy however its use is controversial. It is technically straightforward however it is not without significant complications and although there is currently unequivocal evidence available that it can be a life saving intervention, evidence that outcome is improved over and above standard medical therapy is less forthcoming. This narrative review considers the current role of decompressive craniectomy in the management of neurological emergencies and focuses on four specific questions, namely; (i) Is the decompressive craniectomy a life saving procedure? (ii) Does decompressive craniectomy improve outcome? (iii) Are there any risks associated with decompressive craniectomy? (iv) How do patients feel about their eventual outcome? Finally the future directions for the use of decompressive craniectomy are explored.

The current role of decompressive craniectomy in the management of neurological emergencies.

Decompressive craniectomy has been used as a lifesaving procedure for many neurological emergencies, including traumatic brain injury, ischaemic stroke, subarachnoid haemorrhage, cerebrovenous thrombosis, severe intracranial infection, inflammatory demyelination and encephalopathy. The evidence to support using decompressive craniectomy in these situations is, however, limited. Decompressive craniectomy has only been evaluated by randomized controlled trials in traumatic brain injury and ischaemic stroke and, even so, its benefits and risks in these situations remain elusive. If one considers a modified Rankin Scale of 4 or 5 or dependency in daily activity as an unfavourable outcome, decompressive craniectomy is associated with an increased risk of survivors with unfavourable outcome (relative risk [RR] = 2.9, 95% confidence interval [CI] = 1.5-5.8, p = 0.002, I(2 )= 0%; number needed to operate to increase an unfavourable outcome = 3.5, 95% CI = 2.4-7.4), but not the number of survivors with a favourable outcome (RR = 1.5, 95% CI = 0.9-2.6, p = 0.13, I(2 )= 0%).

The influence of clinical evidence on surgical practice.

Given the considerable interest in the use of evidence-based medicine to guide clinical practice, it is surprising that the results of a recent randomized controlled trial have been met with such a limited response. The DECompressive CRAniectomy study investigators have recently published the results of a landmark trial in neurosurgery, comparing early decompressive craniectomy with standard medical therapy in patients who developed intracranial hypertension after diffuse closed traumatic brain injury (TBI). This is the first ever randomized controlled trial investigating the surgical management of adult patients with severe TBI. The trial clearly demonstrated that early decompression did not provide clinical benefit; however, rather than having a significant impact on clinical practice, it has been almost uniformly criticized. While there were some problems with randomization and crossover, we feel that the trial has been somewhat misinterpreted and in this article we address some of the key issues.

An update on the management of traumatic brain injury.

The management of traumatic brain injury (TBI) continues to evolve in a number of key areas. In the first instance there have been major advances in clinical information gathering and interpretation such that there are mow sophisticated prognostic models readily available. Secondly, technological advances have allowed the introduction of advanced multimodal monitoring which can provide real time information regarding the complex physiological and biochemical derangements that occur following TBI. Finally recent clinical trials have raised important questions regarding the efficacy or otherwise of important therapeutic options most notably hypothermia and decompressive craniectomy. The aim of this update is to highlight some of the areas where there has been advancement and controversy.

Neurotrauma and the rule of rescue.

The rule of rescue describes the powerful human proclivity to rescue identified endangered lives, regardless of cost or risk. Deciding whether or not to perform a decompressive craniectomy as a life-saving or 'rescue' procedure for a young person with a severe traumatic brain injury provides a good example of the ethical tensions that occur in these situations. Unfortunately, there comes a point when the primary brain injury is so severe that if the patient survives they are likely to remain severely disabled and fully dependent. The health resource implications of this outcome are significant. By using a web-based outcome prediction model this study compares the long-term outcome and designation of two groups of patients. One group had a very severe injury as adjudged by the model and the other group a less severe injury. At 18 month follow-up there were significant differences in outcome and healthcare requirements. This raises important ethical issues when considering life-saving but non-restorative surgical intervention. The discussion about realistic outcome cannot be dichotomised into simply life or death so that the outcome for the patient must enter the equation. As in other 'rescue situations', the utility of the procedure cannot be rationalised on a mere cost-benefit analysis. A compromise has to be reached to determine at what point either the likely outcome would be unacceptable to the person on whom the procedure is being performed or the social utility gained from the rule of rescue intervention fails to justify the utilitarian value and justice of equitable resource allocation.

The influence of objective prognostic information on the likelihood of informed consent for decompressive craniectomy: a study of Australian anaesthetists.

The aim of this study was to assess the influence of detailed prognostic information on the likelihood of informed consent for decompressive craniectomy for severe traumatic brain injury. The study was a simulation exercise, asking anaesthetists to give opinions as if they themselves were the injured party. Anaesthetists were chosen as they represent a distinct group likely to be familiar with the procedure and the decision-making process, but not necessarily aware of the longer-term outcomes. A two-part structured interview was used. Seventy-five anaesthetists were shown three cases of differing severity of traumatic brain injury. A visual analogue scale (1 to 10) was used to assess the strengths of their opinion. Initially they were asked their opinion with no predictive outcome data. They were then shown the prediction of an unfavourable outcome (Glasgow Outcome Scale severely disabled, vegetative state or dead) and the observed outcome at 18-month follow-up from a cohort of 147 patients (who had had a decompressive craniectomy for severe traumatic brain injury in Perth, Western Australia between the years 2004 and 2008). The opinions of the participants before and after seeing the prediction outcome data were compared. The participants' preferences to consent to the procedure changed after being informed of the predicted risks of unfavourable outcomes (P values < 0.01). The changes in attitude appeared to be independent of age group, amount of experience in caring for similar patients and religious background. These findings suggest that access to objective information on risks of unfavourable outcomes may influence opinions in relation to consent for decompressive craniectomy for traumatic brain injury.

Neurotrauma and the RUB: where tragedy meets ethics and science.

Decompressive craniectomy is a technically straightforward procedure whereby a large section of the cranium is temporarily removed in cases where the intracranial pressure is dangerously high. While its use has been described for a number of conditions, it is increasingly used in the context of severe head injury. As the use of the procedure increases, a significant number of patients may survive a severe head injury who otherwise would have died. Unfortunately some of these patients will be left severely disabled; a condition likened to the RUB, an acronym for the Risk of Unacceptable Badness. Until recently it has been difficult to predict this outcome, however an accurate prediction model has been developed and this has been applied to a large cohort of patients in Western Australia. It is possible to compare the predicted outcome with the observed outcome at 18 months within this cohort. By using predicted and observed outcome data this paper considers the ethical implications in three cases of differing severity of head injury in view of the fact that it is possible to calculate the RUB for each case.

Complications of decompressive craniectomy for head injury.

There is much interest in the use of decompressive craniectomy for intracranial hypertension. Whilst technically straightforward, the procedure is not without significant complications. A retrospective analysis was undertaken of 41 patients who had had a decompressive craniectomy for severe head injury in the years 2006 and 2007 at the two major hospitals in Western Australia, Sir Charles Gairdner Hospital and Royal Perth Hospital. Complications attributable to the decompressive surgery were: herniation of the cortex through the bone defect, 18 patients (51%); subdural effusion, 22 patients (62%); seizures, five patients (14%) and hydrocephalus, four patients (11%). Complications attributable to the subsequent cranioplasty were: infection, four patients (11%) and bone flap resorption, six patients (17%). Syndrome of the trephined occurred in three (7%) of those patients whose bone flap had significantly resorbed. Two deaths (5.5%) occurred as a direct complication of the craniectomy or cranioplasty procedure. I attempted to define what may be regarded as a complication of the decompressive procedure rather than what may be a consequence of the primary pathological process of traumatic brain injury.