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 your father and obtain a history, I can not tell you what the cause of his symptoms is. However, I will try to provide you with some possibilities.
The general medical term for gait instability is ataxia. In general, ataxias could be divided into a few groups (1) those with a known external cause such as alcoholism or other medications or drugs (2) those that occur following infection (3) those that are neurodegenerative, due to loss of cerebellar cells because of a primary abnormality in cerebellar cells as opposed to an external cause such as infection (4) due to an inborn error metabolism and/or a genetic defect that disrupts metabolism in cerebellar cells (5) those that occur in the setting of cancer, known as "paraneoplastic ataxias", and (6) others, including those due to neuropathy, what is termed sensory ataxia.
Cerebelllar ataxia is one type of ataxia occuring due to a problem in the cerebellum, one of the structures in the brain involved in coordination (among other things). In some patients, cerebellar ataxia occurs following an infection that affects the nervous system, in which case it often resolves. Chronic alcoholism can cause cerebellar ataxia; stopping alcohol intake can improve the ataxia but if it is severe, some permanent symptoms may remain. In patients with cerebellar stroke, with intensive physical and occupational therapy over weeks to months, symptoms may become minimal and may even resolve completely. In patients with cerebellar ataxia due to a tumor in the cerebellum, removal of the tumor often improves ataxia significantly, though some remaining symptoms may persist due to removal of normal cerebellar tissue following surgery. And so on. With a normal MRI, stroke and tumor are an unlikely cause of your father's symptoms.
For the inborn errors of metabolism, some treatable examples include betalipoproteinemia, adrenomyeloneuropathy, cerebrotendinous xanthomatosis, familial vitamin E deficiency, maple syrup urine disease, pyruvate dehydrogenase deficiency, Refsum disease, and Wilson disease. Certain features in your history and physical examination will suggest these disorders, because they are most often associated with other abnormalities. Many of these disorders begin in childhood or adolescence/young adult-hood. Management typically relies on dietary modification, vitamin/cofactor supplementation, or drugs to reduce the load of the accumulating toxic metabolite, or removal of abnormal proteins from the blood by a procedure called plasmapharesis. These disorders are exceedingly rare in adults, but can occur.
In cerebellar ataxia due to cancer, what is called a paraneoplastic process and can be diagnosed with blood tests, with removal of the tumor and treatment with an intravenous medication or immunosuppresants, cerebellar function improves.
Other types of cerebellar ataxias that are genetic such as the large group of genetic disorders called "spino-cerebellar ataxias", Ataxia-telangiectasia, Friedreich ataxia, and other mitochondrial disorders are being studied, certain modifications may be helpful but there is not a cure. These have specific features that suggest one type versus another and genetic testing is available for some of them.
Other potential causes of ataxia include a parkinson's plus syndrome such as multi-system atrophy. Symptoms can predominantly be gait instability.
Neuropathy, or a problem in the nerves of the hands and legs, can lead to a gait disturbance. Symptoms may also include sensory loss in the feet, burning, and tingling, and in some cases, muscle weakness. The most common cause is diabetes, but there are several other causes. Neuropathy is best diagnosed by physical examination and a test called EMG/NCS.
Disorders of the lower spine, such as spinal stenosis, can also lead to gait problems.
As you can see, there are many many potential causes to your father's symptoms. If he has not been evaluated by a neurologist, this is recommended. If he has seen a neurologist, then seeing one specialized in gait disorders, such as a movement disorders specialist, may be of benefit.
Thank you for using the forum I hope you find this information useful good luck.
i have the same simptoms , i olso did he MRI, after that the doctor tall me that this "dizzness" is not from the head, i did a complete blood analysis and everything wan normal, X-ray to the lang everything was normal , but for me the problem contunues to go bad by the day
one doc. tall me that the problem cames from the poor brain blood flow and he give to me some pills for expanding the blood vanes, it solve the problem a little bit, so u can resarch about it a litlle bit