Brief Answer:
If brain lesions need to be ruled out MRI is the best test- CT is another test but is less accurate and emits radiation

Detailed Answer:
Hello and welcome to "Ask a Doctor" service,

I carefully read your query.

Headaches are caused by different conditions and the most common ones are tension headache (stress-related) and migraine, which together account for around 90% of headaches.

Sometimes, if the headache a patient is experiencing is not similar to the headache with these two conditions the doctors may ask for further investigations and MRI is one of them. MRI is generally indicated when brain lesions are suspected as the cause. In this case, the patient may have neurological symptoms (weakness or numbness in limbs or other areas of the body, problems with speech, swallowing or balance, etc). Headache at night or severe headaches are other reasons why the doctor may require an MRI.

Due to specific symptoms the patient may have or due to abnormalities in the neurological exam during the consultation, a brain lesion may be suspected. In this case, an MRI is the best test. CT scan may be performed instead but this emits radiation and is not as sensitive as MRI for brain lesions.

To conclude:
- if the doctor suspects a brain lesion as the cause of the headache, MRI is the best test to be done as it does not emit radiation and is quite a sensitive test (accurate).
- Other tests would include CT scan but it really is inferior to MRI due to radiation and also less accuracy for brain scans

I hope this answers your query. I remain at your disposal in case further medical assistance is needed.

Regards,
Dr. Antoneta Zotaj,
General and Family Physician

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