ALEXANDRIA, Va., Jan. 13 -- United States Patent no. 12,521,534, issued on Jan. 13, was assigned to ASAHI INTECC Co. LTD. (Seto, Japan).
"Dilators" was invented by Marina Tsuzuku (Seto, Japan) and Yukihiro Fuseya (Seto, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A dilator includes: a hollow shaft having a tapered portion whose outer diameter of the distal end is smaller than the outer diameter of the proximal end; a distal tip, whose proximal end is located at the distal end of the tapered portion, and which is provided to extend toward the distal end direction; and a spirally-arranged protruding portion provided on at least the outer peripheral surface of the tapered portion. The spirally-arranged...