title: Objective and subjective comparison of the visibility of three echogenic needles and a nonechogenic needle on older ultrasound devices.
abstract: OBJECTIVE
  This study evaluated the visibility of echogenic needles with older ultrasound devices in an in vitro phantom study.
  
  
  METHODS
  We compared three echogenic needles from B. Braun (BB), Unisis (UN), and Hakko (HK) with a nonechogenic needle. Each needle was inserted into an ultrasound phantom 10 times at 30° and 45° with the bevels up. The captured images of the needle and background contrast were digitally analyzed, and the median of 10 insertions for each angle was calculated to determine objective needle visibility. Needle images were also shown to 12 anesthesiologists to evaluate subjective visibility on a five-point Likert scale.
  
  
  RESULTS
  The shafts of all the echogenic needles were significantly more objectively visible than the nonechogenic needles. Subjective visibilities of the BB and UN needles were significantly higher than that of the nonechogenic needle. Therefore, the BB and UN needles were judged to have more than fair subjective visibility. However, subjective visibility of the HK needle was consistently and significantly lower than that of the BB and UN echogenic needles. At 45°, the HK needle had nearly the same poor visibility as the nonechogenic needle.
  
  
  CONCLUSIONS
  The results of our study indicate that the BB and UN needles are more visible than nonechogenic needles in an ultrasound phantom, even on older devices.
authors: Department of Anesthesiology, Kawaguchi Municipal Medical Center, Saitama, Japan; Department of Anesthesiology, Jikei University School of Medicine, Tokyo, Japan. Electronic address: k-n@jikei.ac.jp.
authors: Kiyotaka
authors: K
authors: Nakagawa
authors: Department of Anesthesiology, Kawaguchi Municipal Medical Center, Saitama, Japan; Department of Anesthesiology, Jikei University School of Medicine, Tokyo, Japan.
authors: Tomohide
authors: T
authors: Kamiya
authors: Department of Anesthesiology, Kawaguchi Municipal Medical Center, Saitama, Japan; Department of Anesthesiology, Nihon University School of Medicine, Tokyo, Japan.
authors: Kazuo
authors: K
authors: Arakawa
authors: Department of Anesthesiology, Jikei University School of Medicine, Tokyo, Japan; Department of Intensive Care, Saiseikai Yokohamashi Tobu Hospital, Kanagawa, Japan.
authors: Sonoo
authors: S
authors: Akiyama
authors: Department of Anesthesiology, Kawaguchi Municipal Medical Center, Saitama, Japan; Department of Anesthesiology, Nihon University School of Medicine, Tokyo, Japan.
authors: Katsuhiro
authors: K
authors: Sakai
mesh_terms: D006801:Humans; D009339:Needles; D009407:Nerve Block / Q000295:instrumentation*; D018084:Ultrasonography, Interventional / Q000295:instrumentation*
keywords: echogenic needle; needle visibility; ultrasound-guided nerve block