What is the diagnosis?
Aneurysm of the right middle cerebral artery.
What is the prevalence of this condition in the general population?
Variably reported between 0.5-8.0%. A safe ball park number is that 2% of the population have an aneurysm.
Where is the exact location of the pathology?
At the trifurcation of the right M1 segment of the right MCA.
What is the main risk with this finding and how would you quantify it?
Subarachnoid haemorrhage from aneurysm rupture: 0.5-2.0% per year (depending on size and annual growth rate). The risk may be negligible in very small aneurysms (7 mm and less), although how this impacts on followup and treatment of incidentally found aneurysm varies greatly from institution to institution.
Would this aneursym be suitable for endovascular coiling? Explain.
No. Not only are MCA aneurysms in general unfavourable, but in this case the morphology of this aneurysm (incorporating the origin of the superior, middle and inferior divisions) would make it very difficult to treat endovascularly without resulting in a MCA territory infarct.
In case of subarachnoid haemorrhage, what is the survival rate?
About two thirds of cases, but less than half in re-bleeding.
Large aneurysm at the branching M1 segment of the right middle cerebral artery, giving off superior middle and inferior vessels (MCA trifurcation). No signs of recent haemorrhage. The left supraclinoid internal carotid artery is ectatic, incorporating the origin of the PCOM, but no focal aneurysm can be identified.