I'm not sure if you are still reading this thread, but I thought I should share - I had a very similar experience nearly a year ago.
I also had just over 100 dives, though those 100 dives were from a year and a half of diving so I was diving fairly regularly. I had done the exact dive probably five times before. I was on 36% nitrox, max depth of 46 feet in a small cavern (yes I was trained for that environment) for about 45 minutes. It was an uneventful dive, with a slow ascent. Shortly after surfacing while floating in the surface pool I became paralyzed from the neck down, and had some visual problems (like a migraine aura). I was given O2 while still in the water for probably 15 minutes or so and was able to walk myself out of the site, which involved some steep stairs. I went to the hospital and called DAN, who (not surprisingly) said given the profile and the quick resolution of symptoms without recompression that it was most likely not DCS. After a migraine pill, O2, and IV fluids I went home.
The next day I had some residual symptoms - numbness in my upper extremeties - and went back to a hospital, called DAN, and ended up doing one chamber ride, probably more as a precaution. The chamber doc was not entirely convinced it was DCS either, but advised I not dive for some time. I went on a mission to see what happened. I was tested for a PFO and did not have one. After visiting several doctors, it seemed most likely that it may have been a complicated migraine with peripheral neurological involvement.
I had a trip planned and payed for Truk lagoon shortly after I was allowed to return to the water, and was worried that the middle of the pacific doing some intense diving was not a good "first dive back" environment. Worried about the trip, I'll admit I returned to the water a little earlier than recommended (18 weeks rather than 24), doing shallow dives on high mixes.
When I finally did moderately deep wreck dive (the USS Mohawk - max 85 ft, average around 65, 45 min total dive time), I dove 34% and stayed well within decompression limits. I did a longer-than-normal half stop (5 min) and a longer-than-normal safety stop (7 min), and was careful to ascend slowly. Nothing about that dive said DCS, the only thing I had going against me was the prior history of what might have been but didn't really seem like a hit.
Ascending from my safety stop I lost feeling below my waist. Again, I had visual problems, and developed a migraine. This time, it did not resolve with O2. I was airlifted to the nearest chamber (Orlando). After my first ride, about 7 hours (a padded table 6) I was not better. The next morning, I was worse. I lost the ability to walk and to control bodily functions. I was given a catheter and a wheelchair.
I spent the next week in the hospital in the chamber every day. When I wasn't in the chamber I was either getting some test or in physical or occupational therapy. I did a total of 9 rides and spent almost 48 hours in the chamber.
That was over 6 months ago and I still don't have normal sensation in my legs or feet. I can walk now and no longer need a catheter. On bad days I might wear an adult diaper and use my cane. I am 28 years old. Some days, I feel 80.
My point is, PFO or not, if your wife wants to dive again PLEASE be very, very careful. My experience was very similar to your wife's at first. If I had stopped after the first time it happened, I would be in a lot better shape today. Diving was a big part of my life and I didn't want to let it go - but in the end it wasn't my choice.
