A 71-year-old woman with a history of hypertension, hyperlipemia, angina was admitted to our neurology department for paroxysmal buzzing of the brain. Physical examination showed the bilateral decreased hearing. The cerebral magnetic resonance imaging (MRI) of the patient indicated multiple cerebral infarctions and bilateral demyelination in the centrum semiovale. The cerebral MRA indicated arteriosclerosis of cerebral arteries, and stenosis of bilateral middle cerebral arteries. For further diagnosis, the patient took DSA subsequently. Total amount of iopamidol (Bracco Imaging Italia S.r.L.) used was 110 ml during the procedure. The DSA showed that the patient had bilateral embryonal posterior cerebral arteries, the left middle cerebral artery was 40% stenosis and bilateral vertebral arteries were tortuous. There was no obvious calcification of the aortic arch, only once angiography was done in the arch using 25ml iopamidol. 10 minutes after the aortic arch angiography, the patient manifested mild headache. The pain was bearable, and the patient could cooperate the procedure. The DSA finished 20 minutes later,there was no hemorrhage or vasospasm during the procedure. Headache was continuous, and the patient suffered nausea and vomiting. The immediate physical examination showed no obvious abnormal sign. The patient was treated with 8mg ramosetron and 10mg dexamethasone. After 20 minutes observation, the symptoms were relieved. And the cerebral CT-scan at this moment was normal (Figure1 A, B, C). 2 hours later, the patient manifested dizziness with nausea and vomiting, she was treated with 8mg ondansetron and 20mg diphenhydramine. Compound sodium chloride injection was used to facilitate the elimination of the contrast agent meanwhile. The treatment alleviated the symptoms. 4 hours after the procedure,the patient manifested dizziness again, 5mg dexamethasone was administered, but the dizziness was not relieve, and she vomited again. At 11 hours, the dizziness was alleviated, but the blood pressure rose to 183/92mmHg, the patient was drowsy, but could answer questions correctly,pupil diameters of both eyes were normal and equal, pupillary light reflex was sensitive, and the movement of the limbs was normal. Then the patient was treated with 30mg nimodipine tables to alleviate the high blood pressure. 14 hours after the procedure the patient fell asleep, but at 17 hours, the electrocardiograph monitoring showed sudden respiratory failure, pulse oxygen saturation reduced to 88%, and gradually declined. The patient was coma state, sighing respiration, the pupil diameters of both eyes were not equal and unreactive, the left one was 4.5mm and the right one was 3mm, limbs drop test was positive, Babinski sign was negative. Cerebral hernia was considered due to the sudden deterioration. The patient was treated with oxygen inhalation, 20% mannitol, nikethamide, lobeline and diprophylline. And the patient was transferred to intensive care unit for further treatment after cardio-pulmonary resuscitation,endotracheal intubation and mechanical ventilator treatment. 2 days after the procedure, cerebral CT-scan indicated diffuse cerebral edema, loss of grey-white differentiation, effacement of the cerebral sulci and decrease in cerebrospinal fluid space (Figure1 D, E, F). The patient was treated with dehydration, mechanical ventilator, anti-infection etc., but the diffuse cerebral edema did not improve. 9 days after the procedure, the third cerebral CT-scan showed the cerebral edema became much more serious, the ventricles were disappeared and there was hyperdense in the subarachnoid space which was considered to be pseudo-subarachnoid hemorrhage due to the serious cerebral edema [10] (Figure1 G, H, I).15 days after the procedure, the cerebral CT showed unrelieved diffuse edema of the brain, and the hyperdense in the subarachnoid space still existed (Figure1 J, K, L). All these cerebral CT-scans did not show intra cerebral hemorrhage or infarct happened in this patient. The patient was continuous deep coma status, the brainstem reflexes disappeared, and died 56 days after that sudden deterioration.