Thanks! He has had awork-up, albeit possibly not complete by your standards. He was puit under anesthesia, scoped thru his throat area and thoroughly examined to no avail. Since this has been an ongoing concern, there was a thorough examination to determine if he had possibly contracted a splinter from the "puppy stage" of chewing everything within sight. Still - no concrete answer.

You refer to "Blasto" what is it? It is a term I am not familiar with!