Polymers help make possible one of the world’s smallest stents for babies

Health |  2 min. read

We’re never smaller than when we first enter the world as newborns.

So when a baby gets sick — the medical tools a doctor uses have to be VERY small.  And sometimes VERY small, has been smaller than our technology was up to.

That makes this little bit of medical news, potentially big news.

You might know that a “stent” is an artificial tube, made to go inside a real “tube” in our bodies, like an artery — when something has gone wrong, like a blockage.

That means a stent isn’t very big, even the one adults might get.  But since babies are even smaller, if a baby needs a stent, that has to be even smaller too.  And too small for us to make, in some cases.

But now a new approach, using polymers and lasers, might make “too small”, part of the surgical kit of the future.

Researchers at ETH Zurich have produced the world’s smallest stent.  FORTY times smaller than anything previously produce. This new stent is about the thickness of three strands of hair.  Small enough for a baby.  Big enough to do its work.

The team at ETH Zurich used a laser to cut a very precise and small mold.  Then a special “shape-memory” polymer goes into that mold.  When the polymer sets, the mold is dissolved and there — is a very tiny stent.  The “shape-memory” is important because the stent has to be pushed, though gently, into place.  So if it gets mushed a bit being pushed in, the stent will return back to its original shape.

Oh, and that polymer?  Made from petrochemicals like ethylene and propylene, of course. The complex polymer used comes from Norland Products, which is a mix of mercaptoesters and triallyl isocyanurate. Big tongue-twisters with complex chemistry.

It is still in the lab stage, but the first results are promising.  We’d say keep an eye out for it — but none of us have eyes that can see something less than 100 micrometers in diameter.