How the Meeting is Organized The numbering scheme encodes the day and time block into the abstract number. For example, for an abstract numbered as TU-D4-05, the TU corresponds to the day of the week (of SU, MO, TU, WE, TH), the D corresponds to the time block (of A, B, C, D, or E), the 4 corresponds to the track number (of 1 through 6). This is shown in the figure below: The organization for each day (Monday - Thursday) is shown in the table below: Track 1 Track 2 Track 3 Track 4 Track 5 Track 6 Track 7 Block A 7:30 - 8:30 am A1 A2 A3 A4 A5 A6 A7 Block B 8:35 - 9:35 B1 B2 B3 B4 B5 B6 B7 Break 9:30 - 10:00 Block C 10:00 - 12:00 C1 C2 C3 C4 C5 C6 C7 Lunch 12:00 - 1:30 Block D 1:30 - 3:30 D1 D2 D3 D4 D5 D6 D7 Break 3:30 - 4:00 Block E 4:00 - 5:30 E1 E2 E3 E4 E5 E6 E7 This scheme (above) is used throughout the meeting, except on Sunday. This year, there are two one-hour refresher course blocks, Block A and B. Blocks C and D correspond primarily to the scientific sessions, however there is an occasional symposium in these time blocks as well. Block E is reserved for the afternoon symposia. In general, Tracks 1 and 2 have been assigned to diagnostic, and Tracks 4 and 5 have been assigned to therapy sessions. Track 3 is used for overflow from other tracks, Track 6 has been assigned to ultrasound sessions and Track 7 has been assigned to nuclear medicine. An effort was made to keep the room the same for each track, but there is an occasional exception. Poster and Paper sessions are laid out spatially, not temporally like the oral presentations. Poster have a PO instead of the day, and papers have a PA instead of the day. Similarly, EP stands for Electronic Posters. A complete description for Posters and Papers layout is given in the exhibit hall in the designated poster area. The organization of the abstracts numbering was meant to improve the efficiency of finding one's way around the meeting. This will only be true if the attendees are aware of the rationale for and how to use the numbering scheme.