I voted Lung Expansion injury and Other for the same incident, which is really the only one I've ever been involved with.
It happened during a checkout dive for a Deep certification. There were 4 students and 1 instructor during the course which took place in July of last year. Dive was to a maximum depth of 106' for a total duration of 29 minutes. Fairly normal profile. A few short stops at some platforms and objects of interest on the way down to a platform at 99ft. Spent about 10 minutes at 99' doing math, etc. with a brief drop down to 106' before beginning the ascent.
During the ascent, another student seemed to panic, and at about 80' she started to dart toward the surface. The instructor responded quickly, and was able to get her to calm down rather quickly. She indicated she was OK, and we continued up. We did surface marker deployment on a platform at 17' during a slightly extended safety stop. The diver who panicked did not want to participate in that activity, but still signed OK. When the rest of us were done, we ascended.
As soon as the panicked diver reached the surface, her regulator was out of her mouth, and she was gurgling on each breath and clearly in distress. Another instructor from the same dive shop had just arrived with an OW student. My instructor (shop owner) instructed her to get the oxygen from his truck. My instructor removed the diver's BC, and asked me to bring it up. Instructor got her out of the water, and both instructors did a good job of coordinating responsibilities. One diver was on the phone with 911, I was sent to the dive site office for a defibrilator (they only had a test unit), and remained by the road to flag down the paramedics.
Paramedics got there right as the O2 was pretty much exhausted. They did an assessment, and took her to the hospital. I had to give a statement for the dive shop.
I talked to both the instructors and the diver later. She was initially suspected of AGE due to the sudden onset of symptoms. AGE was later ruled out, and diver was suspected of DCS and pulmonary edema. She took two chamber rides, though the Dr later believed that DCS was negative. They did a full analysis of her dive gear, and could not find any leaks or other problems. We could only speculate that she managed to inhale some water while trying to look up the dive site wall, and panicked. She later continued her instruction and did complete the course.
The OW student who was getting ready to dive when our group surfaced was a bit scared initially, but the rest of us convinced him that this was not a normal occurrence. He completed his checkout dives and attained his certification.