Myasthenia Gravis Support Group
Myasthenia gravis (MG) is a neuromuscular disease leading to fluctuating muscle weakness and fatiguability. The hallmark of myasthenia gravis is muscle weakness that increases during periods of activity and improves after periods of rest. Although myasthenia gravis may affect any voluntary muscle, muscles that control eye and eyelid movement, facial expression, and...
So I found some information below. If what I am having are too subtle to detect on an exam, I guess it's not impossible for me to have the vision issues that I am having. I read about pseudo internuclear ophthalmoplegia myasthenia gravis which can mimic true INO.
What is Internuclear Ophthalmolplegia?
Internuclear ophthalmoplegia (INO) is the classic visual problem of the eye movement system in MS and is seen in 22 percent of individuals with the disease. INO can involve abnormal movements of one or both eyes. INO is the result of an inflammatory demyelinating lesion in the pathway joining the eye muscles that allows us to move both eyes simultaneously when looking to the side. This pathway is called the medial longitudinal fasciculus (MLF), and is located in the brainstem. With an MS lesion affecting the MLF on the right side of the brainstem, the right eye can not look towards the nose (to the left), but the left eye can move out towards the left. The right eye will, in a sense, try to call the other eye back towards the right side if gaze to the left is maintained. This will result in involuntary, rapid, rhythmic horizontal movement of the left eyeball (nystagmus). It is this combination of failure of one eye to look towards the nose, and nystagmus of the other eye that identifies INO. INO results in double vision (diplopia), since the eyes are not able to focus on the same target. When looking to the one side, if either eye is covered, the double vision will go away. Another abnormality that may be seen is double vision on upward gaze, since the eye on the side of the affected MLF will often be able to look higher than the other eye. ****Some INOs can be quite subtle, and difficult to identify, while others are obvious. In addition to double vision, individuals can experience visual confusion, transient visual sensations of objects swaying back and forth (oscillopsia), reading fatigue, and loss of depth perception (stereopsis)*****. Intravenous steroid therapy can be administered for acute INO.
I know this covers INO for MS but there are case studies where MG can mimic these same visual symptoms. I am just wondering if I am falling in that subtle group which is giving me some of the waviness. I am going to the Mayo Clinic on August 20th to see a neuromuscular specialist. They're going to do a consultation and then run the single fiber EMG I believe. The said to expect to be there all day and that I may want to choose to stay overnight in case the doctor wants to order additional tests. I had this done in 2008, but it wasn't positive. I left there thinking that maybe there was something wrong my the blood work and that I may not have MG but I have had it checked many times since then and it's always high. My Neuro stated I had MG and he had seen patients that had mild symptoms that didn't have a positive single fiber emg. Who knows, maybe the tech did it wrong. With the amount of weakness and visual issues I am having now, i think the results are going to be positive since I can actually notice weakness in my limbs and not just with the bulbar muscles.
What is Internuclear Ophthalmolplegia?
Internuclear ophthalmoplegia (INO) is the classic visual problem of the eye movement system in MS and is seen in 22 percent of individuals with the disease. INO can involve abnormal movements of one or both eyes. INO is the result of an inflammatory demyelinating lesion in the pathway joining the eye muscles that allows us to move both eyes simultaneously when looking to the side. This pathway is called the medial longitudinal fasciculus (MLF), and is located in the brainstem. With an MS lesion affecting the MLF on the right side of the brainstem, the right eye can not look towards the nose (to the left), but the left eye can move out towards the left. The right eye will, in a sense, try to call the other eye back towards the right side if gaze to the left is maintained. This will result in involuntary, rapid, rhythmic horizontal movement of the left eyeball (nystagmus). It is this combination of failure of one eye to look towards the nose, and nystagmus of the other eye that identifies INO. INO results in double vision (diplopia), since the eyes are not able to focus on the same target. When looking to the one side, if either eye is covered, the double vision will go away. Another abnormality that may be seen is double vision on upward gaze, since the eye on the side of the affected MLF will often be able to look higher than the other eye. ****Some INOs can be quite subtle, and difficult to identify, while others are obvious. In addition to double vision, individuals can experience visual confusion, transient visual sensations of objects swaying back and forth (oscillopsia), reading fatigue, and loss of depth perception (stereopsis)*****. Intravenous steroid therapy can be administered for acute INO.
I know this covers INO for MS but there are case studies where MG can mimic these same visual symptoms. I am just wondering if I am falling in that subtle group which is giving me some of the waviness. I am going to the Mayo Clinic on August 20th to see a neuromuscular specialist. They're going to do a consultation and then run the single fiber EMG I believe. The said to expect to be there all day and that I may want to choose to stay overnight in case the doctor wants to order additional tests. I had this done in 2008, but it wasn't positive. I left there thinking that maybe there was something wrong my the blood work and that I may not have MG but I have had it checked many times since then and it's always high. My Neuro stated I had MG and he had seen patients that had mild symptoms that didn't have a positive single fiber emg. Who knows, maybe the tech did it wrong. With the amount of weakness and visual issues I am having now, i think the results are going to be positive since I can actually notice weakness in my limbs and not just with the bulbar muscles.
Love, Becca
I was worried your MG diagnosis was in question... it happens all too often and it is not something we want to "start over" with again right?
I hope you get the answers to your new issues and that they are an easy fix!
Blessings to you!