Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with your doctor.
Without the ability to examine you and obtain a history, I can not tell you what the exact cause of your symptoms is. However I will try to provide you with some useful information.
In general, an MRI of the brain with contrast excludes tumors of the brain. Tumors of the optic nerve would require an opthalmologist, however, an eye exam would not be expected to diagnose a tumor of the brain not seen on MRI. I am not sure what the nodules you are talking about are.
There are several causes of headaches. Headaches can be divided into primary and secondary. Primary headache disorders are headaches without a direct cause. Secondary headache disorders are due to an underlying problem, such as a tumor, medication side effects, central nervous system infections, clots in the veins in the brain etc. An MRI of the brain excludes many of the latter. However, there are certain secondary causes of headaches that i will discuss below.
If you are older than the age of 55, one potential causes is called giant cell arteritis or temporal arteritis. This is due to an inflammation in the temporal artery and other arteries in the body. Symptoms include one sided headache pain in the temple and jaw that may be triggered by chewing. This condition can be diagnosed by a blood test called an ESR and a biopsy of the artery. It is very important to rule this diagnosis out as it is highly treatable and if left untreated it can lead to vision loss. It is exceedingly rare in people younger than 55, and is more common in even older age groups.
If you are overweight, one possible cause is benign intracranial hypertension, also called pseudotumor cerebral, or idiopathic intracranial hypertension. It is a disorder characterized clinically by headaches and vision loss, and sometimes tinnitus (ringing in the ear that is synchronous with the pulse). Dizziness may also be a symptom. The headache is usually global (all over the head) and pressure-like; the headache presentation can be variable. BIH predominantly occurs in people who are overweight, women, and those taken specific medications such as retin-A (the acne medication), vitamin A, and tetracycline antibiotics.
If it is decided that you have a primary headache disorder, there are several medications that can be tried to control your symptoms.
In treating chronic headaches such as in yourself, the treatment should include two types of medications: preventative therapy and abortive therapy. Preventative therapy is a medication that would be taken every day regardless of whether or not a headache is prevent. This type of medication is used to prevent headaches from occurring, and there are several types including but not limited to beta blockers such as propranolol, calcium channel blockers such as verapamil, and others including topamax, depakote, elavil, etc. A lot of these medications were invented for other uses and are used not only for headache but also epilepsy and depression. They have proven very effective in preventing headaches. The second medication is abortive, meaning it is used when a headache is coming on. The medication used depends on the nature of a headache. If it is a migraine type headache, a group of medications called triptans can be used. And so on. However, with frequent use of abortive medications including triptans, tylenol, advil, and others, medication overuse headache occurs. This requires a specific treatment in which the over-used medications are slowly stopped and replaced with more long-acting medications. Tylenol with caffiene, and similar medications, can cause medication overuse headache if used too frequently. Lyrica, which is used for fibromyalgia, can be used for chronic headaches too.
Topamax can cause mental slowing, as you mentioned above. Another cause of mental slowing is thyroid problems, so it may be beneficial for you to discuss having your thyroid checked with your doctor.
If you have not been evaluated by a headache specialist (a neurologist specialized in headache medicine) this may be beneficial to you.
Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.
How do I find a neurologist that specializes in headache medicine? I am ready to drive to the Cleveland Clinic.