This won't come as a surprise to anyone who's ever held their breath during a heavy squat, but a study published in September's Archives of Ophthalmology indicates that performing the Valsalva maneuver increases intraocular pressure (the pressure within the eyeballs).
The downside of this long-term is that there is a slightly increased risk of getting normal-tension glaucoma, which is a little more common in people who've experienced frequent pressure changes in their eyes. I suspect bungee-jumping instructors are at the top of the 'most likely' list.