Glaucoma and cataracts are not an issue WRT welding beyond standard safety practices. On the other hand a pacemaker/defibrillator is a welding issue. With an implanted cardiac device it is best not to weld but if you must my device maker says:
Do not exceed 160 amps, stay away from the welding machine when it is supporting a weld, bring the leads to the weld site from in front of you N O T with the leads passing by you to the weld site, twist the leads to make a twisted pair cable so magnetic field tends to self cancel, place the ground clamp as close as practical to the weld site, and hold the electrode or gun as far as possible from your implanted device. Immediately stop[ welding if you feel dizzy or feel anything unusual.