 We're going to show a couple of nice examples of inter-nuclear ophthalmoplesias. This patient had subacute bacterial endocarditis with a bacterial abscess in the brainstem. Ductions and gays are fairly full looking to the right, but look at this. When looking to the left, his right eye does not AD duct well, and you can see these jerk AB ducting the stagmus of the left eye. So he has a right inter-nuclear ophthalmoplesia. Again, the components are medial-duction abnormalities of the ipsilateral eye and AB ducting the stagmus of the contralateral eye. Now these are really brought out with saccades. This is a nice technique to bring out an INO. Ask the patient to saccade quickly to the right as he's done here, normal to the left. Now look at the lag of the medial-duction of that right eye here. See how it just sort of slowly drifts across? That's a nice way to bring out a subtle INO. I think it shows up fairly nicely. Look at the left eye. You can see the AB ducting the stagmus, and that medial-duction of the right eye just slowly drifts across. You can also do this with an optokinetic drum or strip by moving the target opposite in the direction of the suspected gaze. Now here's another example. Fairly normal when looking to the left. Now look at that left eye, medial-duct slowly compared to the right eye. And again, I think you can see the prominent AB ducting the stagmus of the right eye. This patient has multiple sclerosis. See here, if you were to just look at ductions, you'd think everything was fairly good. You need to bring saccades into action to bring out those subtle INO pleases. It's a very nice technique.