Brief Answer: Yes they are, +medical history +physical exam Detailed Answer: Hello ma'am and welcome. Thank you for writing to us. Derealization is not an isolated condition and in most cases is just considered an accompanying symptom to conditions like: -Anxiety -Epilepsy -Head trauma -Various headaches -Migraine-related -Syncope -Other cerebrovascular disorders So to find the cause for derealization we would have to individually rule out each of the above conditions. 1. Anxiety can be diagnosed or ruled out by a consultation with an expert (eg. psychiatrist) 2. Epilepsy can be diagnosed or ruled out with the help of an EEG, qEEG or MRI 3. Head trauma can be diagnosed with the help of a physical examination looking for neurological signs and an MRI of the head 4. Various headaches can be diagnosed or ruled out with an elaborate medical history and the help of an MRI 5 Migraines can also be diagnosed or ruled out with the help of an MRI, but in most cases may have to be conducted during a migraine headache. Medical history with previous migraine-like headaches will also help. 6. Syncope: Also with the help of medical history and MRI 7. Cerebrovascular disorders: qEEG or MRI So in response to your query, an EEG, qEEG or MRI are all very helpful, but a physical examination and elaborate medical history are also very important for an accurate diagnosis. I hope you find my response both helpful and informative ma'am. Please feel free to write back to me for any further clarifications, I would be more than happy to help. Best wishes.

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