What is meant by "thorough" for a limited ultrasound

In CPT® Assistant May 2009 pg 7 it states that “for an ultrasound study to be separately reported, there must be a thorough evaluation of organs or anatomic region”. What is considered a thorough evaluation in a limited ultrasound for an Emergency Room Physician? Please give an example of both a complete and limited “thorough” evaluation of an ultrasound. Thank you for your assistance.

Heather Greene

re: What is meant by

go to the ED experts: http://www.acep.org/content.aspx?id=30502