[1] Univ Texas Southwestern Med Ctr Dallas, Dept Radiol, Harold C Simmons Comprehens Canc Ctr, Dallas, TX 75390 USA
[2] Univ Texas Southwestern Med Ctr Dallas, Dept Clin Sci, Harold C Simmons Comprehens Canc Ctr, Dallas, TX 75390 USA
[3] Amer Coll Radiol, Reston, VA USA
[4] Univ Ottawa, Ottawa Hosp Res Inst, Dept Radiol, Ottawa, ON, Canada