title: Emerging Points of the Supraorbital and Supratrochlear Nerves in the Supraorbital Margin With Reference to the Lacrimal Caruncle: Implications for Regional Nerve Block in Upper Eyelid and Dermatologic Surgery.
abstract: BACKGROUND
  Blocking the supraorbital nerve (SON) and supratrochlear nerve (STN) by injecting anesthetic distal to the surgical site has the advantage in upper eyelid surgery that avoids obscuring the surgical landmarks and compromising the levator function.
  
  
  OBJECTIVE
  To identify the emerging points of the SON and STN in the supraorbital margin with reference to the lacrimal caruncle.
  
  
  METHODS
  Forty-nine orbits from 27 embalmed Korean cadavers were dissected. The lacrimal caruncle and facial midline were used as landmarks. The emerging points of the SON and STN in the supraorbital margin were determined.
  
  
  RESULTS
  The emerging points of the SON and STN were, respectively, located at 3.0 mm lateral and 3.3 mm medial to the vertical line through the apex of the lacrimal caruncle along the supraorbital margin. The horizontal distances from the facial midline to the emerging points of the SON and STN were 22.8 and 15.2 mm, respectively.
  
  
  CONCLUSIONS
  The optimum sites for achieving SON and STN block are, respectively, located approximately 3 mm lateral and 3 mm medial to the vertical line through the apex of lacrimal caruncle along the supraorbital margin. This knowledge will help the surgeon achieve an easy and accurate approach for regional nerve block.
authors.affiliation: *Department of Anatomy, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea; †Department of Ophthalmology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Korea.
authors.forename: Kang-Jae
authors.initials: KJ
authors.lastname: Shin
authors.forename: Hyun Jin
authors.initials: HJ
authors.lastname: Shin
authors.forename: Shin-Hyo
authors.initials: SH
authors.lastname: Lee
authors.forename: Wu-Chul
authors.initials: WC
authors.lastname: Song
authors.forename: Ki-Seok
authors.initials: KS
authors.lastname: Koh
authors.forename: Young-Chun
authors.initials: YC
authors.lastname: Gil
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059925:Anatomic Landmarks; D002102:Cadaver; D004210:Dissection; D005143:Eyelids / Q000294:innervation* / Q000601:surgery*; D005260:Female; D006801:Humans; D007765:Lacrimal Apparatus / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D009407:Nerve Block