Brain imaging refers to cerebral angiography, which comes in three forms: 1. Digital subtraction angiography, or DSA for short, is also the most commonly mentioned imaging procedure. It is an invasive test in which the patient needs to be imaged under local anesthesia by puncturing the femoral artery and placing a catheter that passes through the heart to deliver a guidewire directly to the brain where a contrast agent is injected. Its accuracy is the highest among all angiograms, and the cost is about 6000 RMB, which is the cost of the procedure only, excluding the various costs incurred in the preoperative and postoperative hospitalization. 2. CT angiography of the head, which is a non-invasive test, but also requires the injection of contrast agent into the elbow vein before the imaging is done, and then the CT scan is used for imaging, and the price is about 2000-2500 RMB. 3. Magnetic resonance angiography Imaging is the simplest angiography, completely non-invasive, without contrast injection, relying on the machine for secondary imaging, and the price is between 600-700 RMB.