Patients who want to have a CT film of the head or an MRI of the head are advised to register with neurology. This is because diseases of the head are mainly seen in the neurological system, such as intracranial tumors, intracranial occupancies, or because of cerebral infarction, cerebral hemorrhage, etc. There are some other head examinations that patients should have, and the choice of what to examine should be based on the patient’s symptoms, age, and previous underlying diseases. If the patient is young and does not have other underlying diseases such as hypertension, diabetes, hyperlipidemia, etc., and the symptoms are mainly dizziness and lightheadedness, a transcranial Doppler examination can be done instead of a head CT examination. If the patient has previous underlying diseases and suddenly has some symptoms of neurological deficits, such as crooked mouth, numbness and weakness of limbs, or unclear speech, a head CT or head MRI should be done. If the patient has epilepsy disease, an EEG is also required.