Help me Understand, Please...

I pulled out the copy of my first sleep study test. I was wondering how I figure the AHI, and what RDI stands for.
The results were this:
Apneas # RDI
OBS 309 55.1
Mixed 33 5.9
Central 64 11.4
Hypopneas 146 26.0
Total (A+I) 552 98.4

My lowest O2 level was at 71%

limb movements/hr total 49.2
limb movements/hr of NREM 48.3
limb movements/hr of REM 55.7

Arousals/hr(NREM) 59.3
Arousals/hr(REM) 80.0
Arousals and awakenings 439
# of Resp Arousals 383

Stage 1 19%
Stage 2 62.1
Stage 3 6.4
Stage 4 0%
Stage REM 12.5%

Latency Stage 1 12.5 Min
" " 2 31.0 Min
" " 3 51.5 Min
" " 4 0
" " REM 189.5 Min

Could someone explain what this all means. I have been on my REMStar CPAP with CFlex and heated humidifer with a ultra mirage full face mask for about a month now. I feel a little better but not much. I am suppose to be getting the AutoPap and a different face mask. Just feeling really tired this week and having major problems with mask leaks and I think I am drooling now which is part of the problem. Just needed to vent.
Thanks

Ok, so i read about AHI and how to figure it. My total sleep time was 336.5. So this gives me a AHI of 98.4. If I calculated correctly which is the same as the RDI.