Intrusion of Dacron suture knot 15 years after scleral buckling

BACKGROUND: We present a case of intrusion of a suture knot 15 years after scleral buckling surgery. CASE PRESENTATION: A 62-year-old woman with high myopia had undergone scleral buckling surgery in her left eye 15 years previously for rhegmatogenous retinal detachment. She recently displayed highly elevated intraocular pressure, with hyphema and vitreous hemorrhage. After the blood was cleared, a ring-shaped protrusion was noted around the equator of the eyeball, with a blue suture knot standing out on its surface and extending into the vitreous cavity at 5 o’clock. The suture knot was removed successfully. Mass spectrometry revealed that the material of the suture was polyethylene terephthalate, or Dacron. One week later, at the place where the suture knot had been located, the choroidal and retinal tissue disappeared and the silicone buckle remained an uncovered intrusion, whereas the rest of the retina was still attached. CONCLUSIONS: The suture knot was possibly the one used to close the drainage port for subretinal fluid, which was covered by the encircling band. During the buckling procedure, covering a nonabsorbable suture, which is usually placed where the sclera is compromised by trauma or the surgical incision, with an encircling band may lead to the intrusion of the suture. Therefore, a soft absorbable suture may be preferable, if possible.