title: An anatomic basis for treatment of retinal artery occlusions caused by hyaluronic acid injections: a cadaveric study.
abstract: BACKGROUND
  In ophthalmic artery occlusion by hyaluronic acid injection, the globe may get worse by direct intravitreal administration of hyaluronidase. Retrograde cannulation of the ophthalmic artery may have the potential for restoration of retinal perfusion and minimizing the risk of phthisis bulbi. The study investigated the feasibility of cannulation of the ophthalmic artery for retrograde injection.
  
  
  METHODS
  In 10 right orbits of 10 cadavers, cannulation and ink injection of the supraorbital artery in the supraorbital approach were performed under surgical loupe magnification. In 10 left orbits, the medial upper lid was curvedly incised to retrieve the retroseptal ophthalmic artery for cannulation by a transorbital approach. Procedural times were recorded. Diameters of related arteries were bilaterally measured for comparison. Dissections to verify dye distribution were performed.
  
  
  RESULTS
  Cannulation was successfully performed in 100 % and 90 % of the transorbital and the supraorbital approaches, respectively. The transorbital approach was more practical to perform compared with the supraorbital approach due to a trend toward a short procedure time (18.4 ± 3.8 vs. 21.9 ± 5.0 min, p = 0.74). The postseptal ophthalmic artery exhibited a tortious course, easily retrieved and cannulated, with a larger diameter compared to the supraorbital artery (1.25 ± 0.23 vs. 0.84 ± 0.16 mm, p = 0.000).
  
  
  CONCLUSIONS
  The transorbital approach is more practical than the supraorbital approach for retrograde cannulation of the ophthalmic artery. This study provides a reliable access route implication for hyaluronidase injection into the ophthalmic artery to salvage central retinal occlusion following hyaluronic acid injection.
  
  
  METHODS
  This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://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.forename: Prawit
authors.initials: P
authors.lastname: Apinuntrum
authors.forename: Thavorn
authors.initials: T
authors.lastname: Phetudom
mesh_terms: D002102:Cadaver; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D009880:Ophthalmic Artery / Q000473:pathology* / Q000601:surgery*; D015356:Retinal Artery Occlusion / Q000139:chemically induced / Q000473:pathology* / Q000601:surgery*
chemical_list: D006820:Hyaluronic Acid