Head trauma and cavernoma haemorrhage - the importance of causality.

Cavernomas are common, benign vascular lesions that affect the brain. Five-year bleeding risk is approximately 3.8% for asymptomatic lesions. Non-spontaneous, traumatic cavernoma haemorrhage has been seldom reported. We present the case of a 49-year-old male with multiple traumatic brain injuries who was managed conservatively. Initial imaging was suggested, and reported as, a traumatic brainstem haemorrhage. However, after resuscitation and a follow-up MRI scan, the diagnosis of a cavernoma bleed was confirmed in keeping with his mild neurological syndrome. This case illustrates the old dictum to treat the patient and not the scan. It serves as one of the few reported cases of post-traumatic cavernoma bleed, and showcases the difficulty in ascribing haemorrhage to spontaneous or traumatic aetiology. We recommend having a low threshold to investigate further in these unusual situations.

Lawsonella clevelandensis causing spinal subdural empyema.

Lawsonella clevelandensis is a recently described species and genus of bacterium in the Corynebacterineae suborder which is Gram-stain positive, partially acid-fast and anaerobic. Very few cases of human infection due to this organism are described and here we seek to add to the limited medical literature. We report the case of a 2-year-old girl who presented with an infected spinal dermoid cyst secondary to Lawsonella clevelandensis which required surgical drainage and a long course of antibiotics. We encountered diagnostic and therapeutic difficulties because this is a fastidious organism which was difficult to culture and ultimately required molecular detection and identification. To the best of our knowledge, this is only the seventh reported case of Lawsonella clevelandensis causing human infection worldwide and the first in the UK. This is the first reported case of Lawsonella clevelandensis infection in a child and the second reported case of this organism causing spinal infection.

Isolated myxopapillary ependymoma of the fourth ventricle: case report and review of literature.

We report a case of isolated myxopapillary ependymoma (MPE) of the fourth ventricle. This is the thirteenth reported case of primary intracranial MPE and the fourth reported case of MPE originating from the fourth ventricle. We suggest that exhaustive clinical and radiological investigation of a spinal ependymoma must be undertaken in all cases of intracranial ependymoma.

In vitro models of neurotrauma.

Traumatic brain injury (TBI) continues to be an important cause of mortality and morbidity, but its pathophysiology is no longer considered an instantaneous irreversible event occurring at the time of injury. Therein, neuroprotection is the attempt to salvage sublethally injured neurons which subsequently die in post-primary sequelae. Key to the discovery of neuroprotective strategies is the development of reliable models of brain injury--both in vivo and in vitro. While numerous studies on in vivo animal models have yielded encouraging results, these have largely failed to translate effectively in humans. One approach out of this impasse may be to re-explore in vitro models to dissect out specific pathophysiological mechanisms and only then test clearer hypotheses on in vivo models, which are more likely to subsequently translate into neuroprotective therapies of the future. Moreover, milder forms of TBI are a more realistic target for therapeutic intervention as more is understood about the vulnerability of surviving neurons and the capacity to salvage them. Several types of injury models are described including transection, compression, barotrauma, acceleration, hydrodynamic and cell stretch models with their advantages and disadvantages discussed in turn, as well as a survey of the cell cultures used, namely immortalized cell lines, primary cultures and organotypic (explant) cultures. We emphasize advances in three-dimensional strain simulation and a recent interest in modelling milder injuries, and argue that in vitro models may be a useful complement to in vivo models in studying TBI.