In one embodiment, a medical device may include an insertion member configured to be inserted into a body opening, and a needle member, movably coupled to the insertion member, configured to be inserted into the body opening. The needle member may include a lumen configured to transfer dissection fluid, a blunt tip located on a distal end of the needle member, and an opening disposed proximate to the blunt tip that is configured to discharge the dissection fluid into a space between tissue layers.
