title: Occurrence of coring after needle insertion through a rubber stopper: study with prednisolone acetate.
abstract: OBJECTIVE
  To evaluate the occurrence of coring after needle insertion through the rubber stopper of prednisolone acetate vials.
  
  
  METHODS
  Two-hundred vials of prednisolone acetate were randomly distributed to two radiologists. Prednisolone acetate was drawn up through the rubber bung of the vials with an 18-gauge cutting bevelled needle and aspirated with a 5-ml syringe. The presence of coring was noted visually. We systematically put each core in a syringe refilled with 3 ml prednisolone acetate, and injected the medication through a 20-gauge spine needle. Computed tomography was performed to measure the size of each coring.
  
  
  RESULTS
  Coring occurred in 21 out of 200 samples (10.5 %), and was visually detected in the syringe filled up with prednisolone in 11 of the 21 cases. Ten more occult cores were detected only after the syringes and needles were taken apart and rinsed. The core size ranged from 0.6 to 1.1 mm, and 1 of the 21 (4.7 %) cores was ejected through the 20-gauge needle.
  
  
  CONCLUSIONS
  Coring can occur after the insertion of a needle through the rubber stopper of a vial of prednisolone acetate, and the resultant core can then be aspirated into the syringe.
authors.affiliation: Université Paris Descartes, Assistance Publique-Hôpitaux de Paris, Service de Radiologie B, Hôpital Cochin 27 rue du Fg Saint Jacques, Paris 75014, France. rcampagna1@gmail.com
authors.forename: Raphael
authors.initials: R
authors.lastname: Campagna
authors.forename: Eric
authors.initials: E
authors.lastname: Pessis
authors.forename: Henri
authors.initials: H
authors.lastname: Guerini
authors.forename: Antoine
authors.initials: A
authors.lastname: Feydy
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Drapé
mesh_terms: D004340:Drug Contamination; D004349:Drug Packaging; D006801:Humans; D008422:Materials Testing / Q000379:methods; D009339:Needles; D011239:Prednisolone / Q000031:analogs & derivatives* / Q000032:analysis; D012408:Rubber / Q000032:analysis*; D013594:Syringes; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: C009935:prednisolone acetate; D012408:Rubber; D011239:Prednisolone