[Paradoxical arterial gas embolism following a direct incisive injury to the skull]

INTRODUCTION

An arterial gas embolism is defined as the presence of air in the arterial circulation. This is an extremely rare cause of stroke that has been described in a multitude of clinical scenarios, generally related to iatrogenic processes. A clinical case is reported in which the arterial gas embolism occurred after a traumatic brain injury, and the most relevant aspects of diagnosis and aetiopathogenesis are reviewed.

CASE REPORT

We report the case of a 52-year-old woman with an open craniofacial wound resulting from an attack with an axe. The initial CT scan found fractures in the left zygomatic, sphenoidal and maxillary arches, as well as pneumocephalus in the cavernous sinuses and the right carotid canal. One hour later, the patient showed a neurological deficit in the right hemisphere, and so a new cranial computed tomography scan with multimodal vascular study was urgently requested, which revealed the mobilisation of the pneumocephalus and ruled out a large vessel arterial occlusion. A shunt study using transcranial Doppler and echocardiography showed the presence of a patent foramen ovale to be the cause of arteriovenous communication that justified an arterial gas embolism. The follow-up CT scan at 48 hours confirmed the appearance of a right parietal ischaemic lesion.

CONCLUSION

This case reflects the simultaneous presence of air in the arterial and venous circulation of the brain, as well as the peripheral communication through a patent foramen ovale. This production mechanism is poorly documented in the literature.

[Anterior circulation embolic stroke secondary to thrombotic occlusion of the brachiocephalic trunk: the usefulness of neurosonological studies]

INTRODUCTION. Atherosclerotic occlusion of the brachiocephalic trunk (CBT) is a rare clinical entity and its presentation in the form of arterio-arterial embolism is uncommon. Early identification of patients with CBT occlusion may have important therapeutic implications. CASE REPORT. A man aged 49 presents with sudden onset symptoms involving the territory of the right middle cerebral artery. Emergent transcranial doppler evaluation showed a flow pattern of proximal right M1 occlusion. After intravenous recombinant tissue plasminogen activator administration, partial recanalization of the vessel was found and the patient improved clinically. Cervical and transcranial duplex sonography demonstrated an occlusion in CBT, which was later confirmed on CT angiography and digital angiography of supraaortic vessels. After aorto-innominate bypass, pathological analysis confirmed the atherosclerotic origin. CONCLUSIONS. The most common clinical presentation of CBT occlusion are transient ischemic symptoms related to steal phenomenon in the vertebro-basilar territory. Symptoms of carotid circulation stroke usually result from arterio-arterial embolic mechanism. Early recognition is important for its therapeutic implications, therefore thrombolytic therapy should be indicated. Neurosonologic study allows rapid and reliable examination on hemodynamic status and the presence of distal embolic phenomena.