Ophthalmologists use 11-0 sutures, which are thinner than the 7-0 sutures used in cardiac surgery.

“the number of the suture of course gets larger the suture gets smaller so an o suture is like you can see how thick it is it's like a piece of rope right 10203 by the time you're at 4-0 it's it's actually quite thin right we use 11-0 exactly and cardiac surgery you're using a 7-0 yeah occasionally there's some guys that would sew the distal end of a coronary artery with an 8-0 and at that level it's already very thin i mean just the slightest tug too much and it breaks but then in ophthalmology you guys were at 11-0”