CT - CT Brain + CTA COW
What kind of cerebral haemorrhage we have on these images?
Extensive subarachnoid haemorrhage occupying the basal cisterns, right sylvian fissure, interhemispheric fissure, and the midline occipital and parietal sulci. There is also a small amount of blood in the posterior horns of the lateral ventricles.
What are the main causes to be considered?
In this specific clinical scenario, we should consider at least: spontaneous ruptured berry aneurysm (~85% of the cases), perimesencephalic haemorrhage, arteriovenous malformation (AVM), spinal arteriovenous malformation, and intradural arterial dissection. That is the reason to the CTA be performed immediately after the noncontrast acquisition.
CTA is normal, with no evidence of aneurysm, vascular malformation, and dissection. What would be a next step to be considered on imaging?
Cerebral angiography. It remains the gold standard for diagnosis and characterisation of vascular abnormalities. The benefit of DSA are a higher spatial resolution: better able to delineate small vessels and characterise vascular morphology, and temporal resolution (contrast can be seen to wash into and out of vascular malformations giving important information in regards to the feeding vessels, such as in dural arteriovenous fistulas (DAVF)).
Extensive subarachnoid haemorrhage occupying the basal cisterns, right sylvian fissure, interhemispheric fissure, and the midline occipital and parietal lobe sulci. Grey-white matter differentiation is preserved, no evidence of definitive intraparenchymal haemorrhage. Small amount of blood in the posterior horn of the lateral ventricles and in the fourth ventricle. The temporal horns are slightly prominent in keeping with hydrocephalus. No midline shift or signs of brain herniation. The extracranial vessels, circle of Willis and vertebrobasilar system opacify normally with no aneurysm, vascular malformation, dissection or significant stenosis detected. Conventional aortic arch anatomy. The left vertebral artery is dominant.