This is a female patient who presented to ER with a severe headache, she underwent CT brain and revealed a basilar artery aneurysm and there was no evidence of aneurysm leakage.

Three hours later, the patient suddenly collapsed, GCS 3/15 and then requested for CT brain again to rule out a ruptured aneurysm and the CT confirmed a ruptured basilar artery aneurysm.

The leakage was probably where the bulge was (arrow).

Unfortunately, this patient had no imaging follow up after being referred to a specialized neuro center. 

Case courtesy: Dr Sameh Salah, Dr Haytham Ramzi and Dr Safwat Almoghazi