Six months after the arachnoid hemorrhage intervention, the main purpose of the review is to review the head CT, CT cerebral angiography (CTA), magnetic resonance angiography (MRA), or digital subtraction cerebral angiography (DSA). Six months after the arachnoid hemorrhage intervention, the main purpose is to review whether there is a newly formed cerebral aneurysm or whether the aneurysm has recurred after the original treatment. Cranial CT can be used to observe whether there is a new subarachnoid hemorrhage; CTA and MRA can observe the condition of cerebral arteries to know whether there is a cerebral aneurysm. Of course, the most accurate test is DSA, which is the gold standard for diagnosing cerebral aneurysms, but this test is an invasive test that requires intra-arterial intervention after puncture through the femoral artery. It is not necessary to do all of the above tests; most people need to have a CTA of the cerebral arteries, and you can consult with your doctor to find out which items need to be reviewed.