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Nasal polyps, a condition where fleshy swellings that look like grapes grow in the nose has historically been treated many ways. Hippocrates reported using a snare to remove them.

Other attempts used OTL from BC to 1750s include cauterization, application of goose fat, filling the nose with oils, aluminum sulfate salts, phenol, an ointment that included lead...

Let's say that by the 1110s, the doctors in Scandinavia, Germany, British Isles, and the former Regions of the Western Roman Empire (there are sooo many "little states" t list them all) have finally figured out most of what they were doing didn't work. They stop the cauterization (tired by the Greeks), phenol (I don't know if it was used in 1110s, it certainly was used in the 1700s), lead ointments (texts include it being used in the nose in the 1300s and the ointment is older than that) and all that. They don't realize that the root problem is inflammation (what is inflammation? The Latin texts say nothing about that), but they finally came to the conclusion the only choice was a snare and polyp removal WITHOUT splitting the soft palate (which some overeager surgeons did). Just hold the nose open, apply a numbing agent, and remove the polyps. This doesn't actually address the root cause, but it's the only historical method that almost always did no harm and on top of not being harmful it offered some relief (recurrence is like 90% with this method and 75% of them will happen in 3 years). Let's also say Fallopius's snare and John Van Horn was made by 1110s (both possible with ROMAN level craftsmanship). In OTL, Hippocrates's improvised snare was cumbersome to use in the nose.

What effects would this have? I haven't read of any monarchs, nobles, sons of monarchs, great grand children of monarchs, nieces/nephews of monarchs, military officers, knights, or inventors suffering from the counterproductive treatments, so I imagine this early POD would actually be small.
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