Chalazion eyelid cyst or Meibomian cyst: Report on Dr. Marchione's blog, 2017

Blepharitis in its mild form is nothing more than flaky tissue around the eyelashes.  the flakes will collect if not washed away, and as an irritant, can morph into something more caustic, starting an inflammation.  if the inflammation persists over years, palpebranoma [eyelid cancer], can result.
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HOWEVER.
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in most of the advanced acute stages of Blepharitis, a large cyst [in the eyelid's center], or a small, swollen and inflamed pile [nearer to the eyelids periphery], can form.  resultant cancer, although occurrent, is more of a rarity.  what happens in the case of a cyst, is puss begins to pool under the skin, and the release of this fluid is blocked by what started the irritant in the first place.  with the more common "pile", similar to a hemorrhoid, small levels of filth are pressured into a portion of the eyelid's corner pores, and the very tiny capillaries beneath these pores criss-cross and constrict each other [forming the pile].
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CURES:  the cyst must be carefully cleaned for a week, and even the fluid might need to be exacted.  for the pile, an opthalmologist will have small sterile foil packages, with an antibiotic ointment, so a visit to this type of doctor for the medicine is necessary.
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Dr. Marchione
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