Elucidation of pathophysiology of intracranial aneurysms based on metagenome analyses of oral bacteria

When intracranial aneurysms occur in arteries, this can lead to weakening of the arterial wall and subarachnoid haemorrhage, which can result in death. Intracranial aneurysms can’t be diagnosed without cerebrovascular imaging tests and there are few clues to indicate their presence. Neurosurgeon Assistant Professor Hirokazu Koseki, Department of Neurosurgery, The Jikei University School of Medicine, Japan, is looking for novel ways to predict the presence of intracranial aneurysms before they rupture. He is investigating the role of oral bacteria, which have been associated with cerebral haemorrhage and dementia, in order to clarify the relationship between oral bacteria and aneurysms. In unprecedented work, he and the team want to map this relationship based on severity of periodontal disease and will utilise metagenomic analysis of saliva to identify the bacterial strains that might contribute to the neuropathology. They will also take samples from the walls of the aneurysms to precisely decipher which bacterial strains can be directly associated with them. The work will enable researchers to establish simple and inexpensive targeted treatment for intracranial aneurysms and is also anticipated to have knock-on effects, being used for the screening of inherent risk factors for the occurrence of intracranial aneurysms. Although there are known risk factors, patients without any of the risk factors can still develop intracranial aneurysms or subarachnoid haemorrhages. Building on existing research that points to association between oral microbiology and neuropathology, Koseki is working to identify further risk factors that might help in diagnosing intracranial aneurysms in patients.