Endoscopic Ultrasound and Pancreas Tail

Hello,

My father recently went in for an Endoscopic Ultrasound with Fine Needle Aspiration regarding a mass on the tail of his pancreas that was seen on 2 CT scans and an MRI.  When the surgery was over with the doctor came and spoke to him and my mom and informed them that he didn't do the biopsy because he couldn't find anything to biopsy.  My question is, can the EUS see the tail of the pancreas?  I was under the impression that ultrasounds don't really have that far of a range and while the pancreas is only 6 or so inches long wouldn't you get a better view of the pancreas head?  Thank you very much for your help!