title: Nasolacrimal polyurethane stent: complications with CT correlation.
abstract: OBJECTIVE
  To evaluate initial results in patients with epiphora secondary to obstruction of the nasolacrimal duct treated by placement of a polyurethane stent, and to discuss the technical problems and complications arising during the procedure, with visualization of the anatomy of the drainage apparatus using computed tomography (CT).
  
  
  METHODS
  We inserted 20 polyurethane Song stents under fluoroscopic guidance after dacryocystography in 19 patients with grade 3-4 epiphora caused by idiopathic obstruction of the nasolacrimal duct. CT scans were obtained following stent placement in all patients.
  
  
  RESULTS
  We focus on the technical problems and complications that arose during these procedures. During negotiation of the guidewire past the obstruction at the level of the junction of the duct with the lacrimal sac, the guidewire created a false passage in a posterior suborbital direction in two cases and towards the posterior midline in another. In all cases the guidewire was withdrawn and reinserted through the proper anatomic route without further difficulty or complications. In two cases the stent was improperly positioned wholly or partially outside the nasolacrimal system (one medially, one posteriorly). In one case the stent was removed and reinserted; in the other it remains in place and functional. CT was performed in all these cases to ensure proper anatomic alignment and determine what had gone wrong. The epiphora was completely resolved in 13 cases and partially relieved in four; there were three cases of stent obstruction. Epistaxis of short duration (1 hr) occurred in seven patients and headache in one.
  
  
  CONCLUSIONS
  Treatment of epiphora with polyurethane stents is a technique that is well tolerated by patients and achieves a high success rate, yet problems in placement may be encountered. Though no major consequences for patients are involved, cognizance of such difficulties is important to avoid incorrect positioning of stents.
authors.affiliation: Department of Radiology, Hospital Universitario de Getafe, Madrid, Spain.
authors.forename: I T
authors.initials: IT
authors.lastname: Pinto
authors.forename: L
authors.initials: L
authors.lastname: Paul
authors.forename: C
authors.initials: C
authors.lastname: Grande
mesh_terms: D000328:Adult; D000368:Aged; D001672:Biocompatible Materials; D003608:Dacryocystorhinostomy / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D004322:Drainage / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007766:Lacrimal Apparatus Diseases / Q000209:etiology; D007767:Lacrimal Duct Obstruction / Q000150:complications / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011140:Polyurethanes; D015607:Stents / Q000009:adverse effects*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D001672:Biocompatible Materials; D011140:Polyurethanes