title: Periorbital and Intraorbital Studies of the Terminal Branches of the Ophthalmic Artery for Periorbital and Glabellar Filler Placements.
abstract: BACKGROUND
  Filler injections for sunken upper eyelid correction and glabellar augmentation at the orbitoglabellar region need to be performed correctly. Precise knowledge of the emerging sites of all terminal branches of the ophthalmic artery is essential for these procedures to be conducted safely.
  
  
  METHODS
  The terminal branches of the ophthalmic artery were studied in both periorbital and intraorbital dissections. The aim of this study was to verify the critical positions of the emerging sites at the orbital septum that may act as potential retrograde channels for filler emboli.
  
  
  RESULTS
  In the 40 eyes examined, the branches of the ophthalmic artery were found to emerge from four different sites. Two substantial emerging sites were situated on both sides of the trochlea of the superior oblique muscle. These sites were located at the superior part of the medial orbital rim (SMOR) and are alternatively named as the epitrochlear and the subtrochlear emerging sites. The other two sites can be regarded as accessory emerging sites due to the comparably smaller artery. Dissection of the intraorbital region revealed small periosteal branches of the infraorbital artery which coursed anteriorly on the orbital floor to form anastomoses with the lacrimal artery. In other areas of the orbital floor, no branches extended from the infraorbital artery. In front of the lacrimal gland, very minute branches descended and coursed along both margins of the superior tarsus but did not course outside the lateral orbital rim.
  
  
  CONCLUSIONS
  A danger zone was located at the SMOR, where the ophthalmic branches emerge to form anastomotic channels. Compression at the trochlea guarantees safe injection of filler, reducing the risk of complication.
  
  
  METHODS
  This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
authors.affiliation: The Chula Soft Cadaver Surgical Training Center and Department of Anatomy, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, 1873 Rama 4 Road, Pathumwan, Bangkok, 10330, Thailand. tansatitapinuntrum@gmail.com.
authors.forename: Tanvaa
authors.initials: T
authors.lastname: Tansatit
authors.affiliation: The Chula Soft Cadaver Surgical Training Center and Department of Anatomy, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, 1873 Rama 4 Road, Pathumwan, Bangkok, 10330, Thailand.
authors.forename: Prawit
authors.initials: P
authors.lastname: Apinuntrum
authors.affiliation: The Chula Soft Cadaver Surgical Training Center and Department of Anatomy, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, 1873 Rama 4 Road, Pathumwan, Bangkok, 10330, Thailand.
authors.forename: Thavorn
authors.initials: T
authors.lastname: Phetudom
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D000067548:Dermal Fillers / Q000494:pharmacology*; D005143:Eyelids / Q000187:drug effects*; D006801:Humans; D007279:Injections, Subcutaneous; D008875:Middle Aged; D009880:Ophthalmic Artery / Q000033:anatomy & histology*; D009915:Orbit / Q000033:anatomy & histology* / Q000098:blood supply*; D012680:Sensitivity and Specificity
chemical_list: D000067548:Dermal Fillers
keywords: Cadaver; Filler injections; Glabellar augmentation; Ophthalmic artery; Sunken eye