Well, as you probably have been told, internuclear opthalmoplegia is the result of a lesion (injury) in the medial longitudinal fasciculus (MLF) which connects the sixth cranial nerve nuclei to the contralateral medial rectus muscle. The consequence is difficulty with adduction of the affected eye, which often lags behind when lateral gaze is conducted.

There is no known literature which would suggest a connection between this disorder and the onset of palpitations. It's also important to realize that when we speak of the Vagus nerve being sensitive, we are referring to it as part of the entire nervous system being sensitive due to elevated stress and anxiety. So your GP is correct if it was stated that the Vagus nerve alone could be subjected to greater sensitivity than the rest of the nervous system.

While MS would have been a good differential diagnosis, I would ask whether both eyes are affected because in most all cases of MS, INO is typically bilateral. Unilateral symptoms would make me think more of a vascular incident. Also, in the absence of rice-grain lesions typically evident on MRI in most cases of MS, I would have run MuSK antibody titres to make certain that Myesthenia Gravis was not of issue since it can mimic almost identically the motility patterns of true INO. The initial symptom of dizziness could have a number of origins and it would be difficult for me to suggest one over the other without medical historical information that certainly should not be posted on an open website forum.

Here would be a short list for thoughts when observing INO in patients - multiple sclerosis, brainstem infarction, brainstem and fourth ventricular tumor, viral infection, mechanical trauma, syphilis, Lyme disease, drug intoxication (phenothiazines and tricyclic antidepressants), subdural hematoma and in pseudo-INO the possibility of myesthenia gravis if other symptoms such as heat intolerance are evident along with positive lab results. Your age of onset would be typical of MS, but in the absence of symptoms beyond INO, I would be looking elsewhere particularly after nearly a decade.

Best regards and Good Health

Okay, no mention was made to suggest that you've suffered a cerebral vascular accident, or stroke. I was merely stating the more common presentation with symptoms as described in your posting and again, was not informed whether your INO is unilateral or bilateral.

I am certainly unable to examine or diagnose you via the Internet and it's very important for you to view my comments in response to readers as a form of medical information, not medical diagnosis.

In the absence of clear signs of MS or other known disease characteristically found to be responsible for INO, I would have suggested that a CT angiogram typically provides far more data about the prospect of vascular accidents. It's ability to discern such events does, however, wane as more time passes, certainly after 10 years or so, which I believe was the timeframe mentioned.

It's also worth inquiring here whether you are experiencing any type of GI problems, which can go a long way to creating the potential for this type of palpitation to occur.

Best regards and Good Health