title: Effect and distribution of contrast medium after injection into the anterior suprachoroidal space in ex vivo eyes.
abstract: OBJECTIVE
  To determine the effects and posterior distribution of injections made into the anterior suprachoroidal space (SCS).
  
  
  METHODS
  The anterior SCS of adult porcine and canine ex vivo eyes was cannulated. Latex injections and high frequency ultrasound (50 MHz) was used to image the effect and distension of the SCS. Flow characteristics and percentage maximal distribution of microbubble contrast injection into the SCS were assessed by 2D and 3D ultrasound.
  
  
  RESULTS
  Mean (SD) distension of the SCS with PBS increased from 1.57 (0.48) mm after injection of 250 μL to 3.28 (0.57) mm with 1000 μL PBS. Eyes injected at physiologic IOP had no significant difference in SCS distension. In real-time 2D ultrasound, the contrast agent flowed from the injection site to the opposite ventral anterior SCS and the posterior SCS. Contrast arrived at the opposite and posterior SCS 7.8 (4.6) and 7.7 (4.6) seconds after injection, respectively. In sagittal images, contrast was visible in 24.0%to 27.2% of the SCS; in 10 of 12 eyes, contrast reached the posterior pole of the eye. In 3D images, contrast medium occupied 39.0% to 52.1% of the entire SCS.
  
  
  CONCLUSIONS
  These results suggest that the SCS can expand, in a dose-dependent manner, to accommodate various volumes of fluid and that it is possible to image the SCS with ultrasound contrast. The authors' hypothesis that a single anterior SCS injection can reach the ocular posterior segment was supported. Further development of SCS injections for treatment of the ocular posterior segment is warranted.
authors.affiliation: Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, North Carolina 27607, USA. gsseiler@ncsu.edu
authors.forename: Gabriela S
authors.initials: GS
authors.lastname: Seiler
authors.forename: Jacklyn H
authors.initials: JH
authors.lastname: Salmon
authors.forename: Rebecca
authors.initials: R
authors.lastname: Mantuo
authors.forename: Steven
authors.initials: S
authors.lastname: Feingold
authors.forename: Paul A
authors.initials: PA
authors.lastname: Dayton
authors.forename: Brian C
authors.initials: BC
authors.lastname: Gilger
mesh_terms: D000367:Age Factors; D000818:Animals; D000867:Anterior Chamber / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002829:Choroid / Q000000981:diagnostic imaging* / Q000378:metabolism*; D003287:Contrast Media / Q000493:pharmacokinetics*; D004285:Dogs; D016503:Drug Delivery Systems; D021621:Imaging, Three-Dimensional; D066298:In Vitro Techniques; D056965:Injections, Intraocular / Q000379:methods; D007840:Latex / Q000493:pharmacokinetics; D045423:Microbubbles; D057972:Posterior Eye Segment / Q000000981:diagnostic imaging / Q000378:metabolism; D012160:Retina / Q000000981:diagnostic imaging / Q000378:metabolism; D013552:Swine; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D007840:Latex