Thanks for the additional information,
Well there are a number of conditions which can explain your symptoms and these wouldnt show up on a normal MRI or a CT scan of the brain as well. Now the first thing to be considered in your age group and particularly in females is that of Migraine. This pain that you have could be due to a Complicated Migraine which is a sub type of Migraine in which numbness and even paralysis on one side of the body can occur. Now Migraine is a clinical diagnosis as no test can definitively diagnose this condition. This condition once diagnosed by exclusion of other more dangerous diseases such as an aneurysm or tumors or even strokes, can be treated with several drugs which can prevent an attack as well. A good strategy is to use drugs like zolmitriptan or imitrex or sumitriptan to abort an acute attack of the migraine and if the pain responds to this drug then it more or less diagnoses the condition. Afterwards several types of drugs can be used to prevent further attacks from occuring suich as,
FlunerazineBeta blockersTopiramateValproic acid
Among many other options.
Another possiblity which should be considered in your case is that of vertebral artery dissection which would manifest as changes in vision alongwith weakness or numbness of one side of the face alongwith dizziness and hearing disturbeances as well. This can be picked up by getting a CT angiogram done of the vessels in the neck and once this is diagnosed the treatment is basically surgical.
Lastly i would also advise getting yourself checked for temporal arteritis which is a condition in which blurring of vision alongwith the type of headache which you have described is common. This can be diagnosed by running a simple tests known as ESR which would be raised in this condition. Definitive diagnosis can be made by doing a biopsy of the temporal artery which runs alongside the head. This can then be treated with simple painkillers alongwith steroids in the dose of prednisone 60 mg per day for a short period of time.
i would suggest that you contact your neurologist and discuss these options with him because youre already on strong painkillers which dont seem to be working and getting to the root of your problem is the key so that you can control these headaches and get better. I hope this helps
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