Internuclear Ophthalmoplegia | INO | Animation | Explained Conceptually

[@NeurologyAnalogy]

I hope you found this analogy helpful :) If you have any ideas for neurology concepts you would like an animated analogy for, let me know below and I'll add them to my list!

[@PzmShafi]

I can say only one thing... Superb, nothing else

[@NeurologyAnalogy]

Thank you for the kind words

[@MohammedHassan-dj8wy]

you are phenomenal!!! no words to describe how elegant that was , really helpful and simplified I wish you could make such analogies in every aspect in medicine.

[@NeurologyAnalogy]

Glad it was helpful!

[@akatsukinoyona7059]

Thank you from the bottom of my heart for saving me to understand this difficult lecture with your helpful explanation🙏🏻

[@NeurologyAnalogy]

Glad to hear that

[@sali11629]

this is one of the best explanations I've found about this topic! Thanks so much!

[@NeurologyAnalogy]

Glad it was helpful!

[@debigdogk9563]

Awesome, simply the best explanation, so far, really don’t know how I found your channel but I did, thank you ❤❤❤❤❤❤

[@NeurologyAnalogy]

Glad it was helpful!

[@franciscodesousa8067]

This is pretty good, keep up the good work. Try increasing your video count ,then maybe post it on groups with large followings like USMLE, or MRCP groups. I'm sure you'll do really well.

[@NeurologyAnalogy]

Thanks for the kind words Francisco :)

[@udaykumarbr1231]

Perfect❤❤❤❤❤

[@NeurologyAnalogy]

thank you for the kind words Uday :)

[@drmurtazarashid7678]

Amazing explanation. Thank you

[@NeurologyAnalogy]

You're most welcome, thanks :)

[@SG-rhqi-pjoknlm]

Great lecture!

[@NeurologyAnalogy]

Thank you for your appreciation :)

[@debigdogk9563]

I have subscribed, liked and shared ❤❤❤❤❤❤

[@NeurologyAnalogy]

Very kind of you :)

[@LaitoChen]

Fantastic!

[@NeurologyAnalogy]

Glad you like it!

[@SaptanshuThakur]

amazing vid! thank u

[@sage9710]

thank you!!!!!!!

[@NeurologyAnalogy]

You're welcome!

[@bennguyen1313]

Is INO the same as 'lazy eye'.. and more importantly can INO be corrected (new connections made?), via eye exercises (Crossing eyes, patch, etc) or supplements (Vitamin-D/A, etc)? If not, is surgery and/or procedures (stem-cells, tetrodotoxin, etc) available for this condition? Is there any doctor(s)/hospital(s) that have become the go-to for INO? About a year ago, my *RIGHT* eye suddenly could not move past the mid/center point... fortunately, full range eventually came back after a few months. Unfortunately, now the *LEFT* eye is not tracking with the right eye, even though it can correctly move anywhere if the right eye is closed. Both the previous and now this new issue, seem related to the Rostral / midbrain.

[@NeurologyAnalogy]

Thanks Ben for the question. INO is not the same as a lazy eye. Lazy eye (amblyopia) is normally due to peripheral causes affecting the eye itself or the extraocular muscles, which over time if left untreated, makes the brain ignores vision from that eye. INO is due to an MLF issue, for which could be due to stroke, MS, tumour etc. INO is not a condition, only a sign of where damage is. Treatment is for the underlying condition, and may not go away. I can't give specific medical advice on KZbin, but based on your experience I would recommend seeing a doctor/Neurologist.

[@DavidOlsen-e3n]

My name is David a Olsen. I have been diagnosed with Parkinson’s since 2017 but I have bad eye movement not so much up and down but left to right it has been since I was young, but it’s worse now since I have my Parkinson’s I’ve been to a regular ophthalmologist and a nuclear ophthalmologist. They tell me there’s not much they can do. Is there any help you can give me, because reading is a very hard for me because I have to move my head back-and-forth because my eyes don’t move side to side with so if there’s any help you can give me it would be greatly appreciated. I could use any help. I could get with this problem.

[@yamone1667]

Why would the damage to the MLF affect the communication between the ipsilateral sixth and contralateral third cranial nerve nuclei? If the Left MLF gets damaged, communication breaks down between the Left third cranial nerve nuclei and the Right sixth cranial nerve nuclei. So, shouldn't it be ipsilateral third and contralateral sixth cranial nerve nuclei?

[@NeurologyAnalogy]

Thanks for the question, Ya Mone. In short, it's a question of semantics. There's so no hard-and-fast rule, but in general, as the impulse goes CN6 → MLF → CN3 (not CN3 → MLF → CN6), it is fair to say that CN6 is ipsilateral, and CN3 is contralateral. Recall that the MLF is named according to where it goes; i.e. left MLF begins on the right, then goes to the left. Hope this helps.

[@yamone1667]

@@NeurologyAnalogy Does this mean that ipsilateral or contralateral is decided based on the beginning of the MLF and not according to the name (where it goes)?

[@NeurologyAnalogy]

It depends where the lesion is; if the MLF is damaged close to the left CN3, then left is ipsilateral to lesion, and right contralateral. If MLF is damaged close to right CN6 before it decussates, then right is ipsilateral to lesion, and left is contralateral. Hopefully makes sense

[@yamone1667]

@@NeurologyAnalogy that makes sense. thanks a lot for the explanation!

[@steengrover7403]

Why can’t you make slow pursuit eye movements without focusing on an object, only saccadic scans? Great video, thanks

[@steengrover7403]

Or being unfocused for that matter

[@NeurologyAnalogy]

Hey Steen, this is because of the differing functions of the saccadic vs the smooth pursuit mechanism. TL;DR: Saccades are fast movements to look at stationary targets. Smooth pursuit helps you follow moving targets If a target is stationary and you want to suddenly shift your gaze to look at it, it is better to use fast saccadic movement to quickly orientate the target to fall onto your fovea, rather than use the slow pursuit mechanism which would take too long. It makes sense that you quickly move the eyes as you already know where it is that you want to look ahead of time (i.e. before your eyes begin to move). If a target is moving, the smooth pursuit mechanism ensures that the moving target continues to fall onto your fovea, regardless of its direction. As you are following a target in real-time, you do not know ahead of time where your eyes should move next, and so you need a mechanism to smoothly follow the target. if you followed target with saccadic movement, the eyes might undershoot or overshoot the moving target, which means you would have times when the target is not directly falling onto your fovea. Hope this helps answer your question

[@vaishnaviagrawal9714]

Great video!!! Beautifully explained. Thank you 😀

[@Vocaloidict]

@@NeurologyAnalogy Does INO behave differently depending on if you use the smooth pursuit vs saccade mechanism? I'm guessing no but correct me if I'm wrong

[@NeurologyAnalogy]

@@Vocaloidict Great question, and you're right - there's no difference because the final common pathway for saccades and pursuit is the CN6 nucleus, which uses the MLF. So regardless of saccades or pursuit, you would see an INO, but to best see an adduction lag, better to use large amplitude saccades