Hello, Is anyone familiar with the average Entrance Skin Exposure for a lumbar spine exam?(L4-S1 view). Is there a reference,URL,etc. that discusses the exam. I conducted a short literature search and found only the AP and LAT data. Please reply directly to me. David J. Dunn RSO NNMC,Bethesda E-mail: djdunn@med.navy.mil Fax: (301)295-5788 Comm: (301) 295-1043