title: LED Light Characteristics for Surgical Shadowless Lamps and Surgical Loupes.
abstract: BACKGROUND
  Blue light has more energy than longer wavelength light and can penetrate the eye to reach the retina. When surgeons use magnifying loupes under intensive surgical shadowless lamps for better view of the surgical field, the total luminance is about 200 times brighter than that of typical office lighting. In this study, the effects of 2 types of shadowless lamps were compared. Moreover, the effect of various eyeglasses, which support magnifying loupes, on both the light energy and color rendering was considered.
  
  
  METHODS
  The light intensity and color rendering were measured on 3 variables: light transmittance, light intensity, and color rendering.
  
  
  RESULTS
  Under shadowless lamps, the light energy increased with low-magnification loupes and decreased with high-magnification loupes. Filtering eyeglasses reduced the energy, especially in conditions where the low-magnification loupe was used. The best color-rendering index values were obtained with computer eyeglasses under conventional light-emitting diode shadowless lamps and with no glass and with lightly yellow-tinted lenses under less-blue light-emitting diode.
  
  
  CONCLUSIONS
  Microsurgeons are exposed to strong lighting throughout their career, and proper color rendering must be considered for easier recognition. Light toxicity and loss of color rendering can be reduced with an appropriate combination of shadowless lamps and colored eyeglasses.
authors.affiliation: Minamiaoyama Eye Clinic, Tokyo, Japan; Department of Ophthalmology, School of Medicine, Keio University, Tokyo, Japan; and Yamada Shadowless Lamp Co., Ltd, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ide
authors.affiliation: Minamiaoyama Eye Clinic, Tokyo, Japan; Department of Ophthalmology, School of Medicine, Keio University, Tokyo, Japan; and Yamada Shadowless Lamp Co., Ltd, Tokyo, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Kinugawa
authors.affiliation: Minamiaoyama Eye Clinic, Tokyo, Japan; Department of Ophthalmology, School of Medicine, Keio University, Tokyo, Japan; and Yamada Shadowless Lamp Co., Ltd, Tokyo, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Nobae
authors.affiliation: Minamiaoyama Eye Clinic, Tokyo, Japan; Department of Ophthalmology, School of Medicine, Keio University, Tokyo, Japan; and Yamada Shadowless Lamp Co., Ltd, Tokyo, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Minamiaoyama Eye Clinic, Tokyo, Japan; Department of Ophthalmology, School of Medicine, Keio University, Tokyo, Japan; and Yamada Shadowless Lamp Co., Ltd, Tokyo, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Minamiaoyama Eye Clinic, Tokyo, Japan; Department of Ophthalmology, School of Medicine, Keio University, Tokyo, Japan; and Yamada Shadowless Lamp Co., Ltd, Tokyo, Japan.
authors.forename: Ikuko
authors.initials: I
authors.lastname: Toda
authors.affiliation: Minamiaoyama Eye Clinic, Tokyo, Japan; Department of Ophthalmology, School of Medicine, Keio University, Tokyo, Japan; and Yamada Shadowless Lamp Co., Ltd, Tokyo, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota