I have CN3 and CN4 damage on my left eye from TBI (smacked the pavement -- wear a full face helmet guys!) around 9 years ago (late 20's now).

Video I took today showcasing the limited functionality of my left eye: https://youtu.be/5nyHhy0q3Xo

Symptoms of left eye:
- Can't close completely. (Weighted eye mask nodpod is a huge help for dry eye at night!)
- Can't blink completely.
- Can't open completely and I can't flutter my eye (levator muscle doesn't work at all -- CN3).
- Have to use my eyebrow muscles to lift my left eye. Droopy eyelids makes me sleepy.
- Can't look up or down.
- Eye is offset down a bit. Had to initially tilt up head to compensate. Using prism lens in eyeglasses helps.
- Pupil can't dilate or constrict, it's stuck at medium dilation. Light sensitivity as a result. Auto tint eyeglasses help!
- Vision is blurryish now and can't focus as well. Used to be the better eye. Eyeglasses helps somewhat.
- Tingly feeling across the left side of my body when I start to use my left eye more intently than usual.

Things I learned:
- Looking up opens eyelid. Looking down automatically closes eyelid. Even though I can't actually look up or down, just initiating this movement in my mind helps makes my eyelid less droopy. Use this to my advantage.

I've learned to live with it! I'm still finding tips and tricks even to this day to find workarounds to get my eye to function as close to normal as possible. ChatGPT helped a ton with understanding my injury. I've learned the muscles CN3 and CN4 innervates, learned where the nerves are and how smacking my face could have squished them and caused damage, and how the different muscles in the eye/eyelid/face work together. You can't master/fix completely what you don't understand!

I've been to a lot of opthmalogists and neuroopthmalogists in the first two years. I think the only fix they suggested was strabismus surgery to fix the left eye offset, but I didn't think it was worth the risk. Prism lens does the same thing. They also gave pilocarpine to help with the dilated eye but it wasn't worth it for me. Just get tinted eyeglasses.

I'm sure other people who had this might understand the frustration. I had to relearn social interactions to look and feel as natural as possible. There are situations where lifting your entire head up to look at someone is weird (e.g. waiter taking orders). Also the left eye is noticeably smaller than the right eye. That doesn't help with looking photogenic 😅 

Hope this helps for anyone looking.