title: Analysis of forces acting upon submacular hemorrhage in pneumatic displacement.
abstract: OBJECTIVE
  To analyze the forces affecting pneumatic displacement of submacular hemorrhage and determine an efficient postoperative positioning method for patients.
  
  
  METHODS
  Geometric analysis of the forces that act upon submacular hemorrhage in the absence and presence of a gas bubble.
  
  
  RESULTS
  A component of gravity force of the hemorrhage parallel to the subretinal space is responsible for pneumatic displacement. This component is largest when the patient is looking straightforward and is absent when the patient is positioned facedown.
  
  
  CONCLUSIONS
  Face down positioning is not optimal for pneumatic displacement of submacular hemorrhage and should be avoided.
authors: Duke University Eye Center, Durham, North Carolina, USA.
authors: Marcin
authors: M
authors: Stopa
authors: Andrew
authors: A
authors: Lincoff
authors: Harvey
authors: H
authors: Lincoff
mesh_terms: D005466:Fluorocarbons / Q000008:administration & dosage*; D006112:Gravitation; D006801:Humans; D008954:Models, Biological; D011312:Pressure; D016684:Prone Position; D012166:Retinal Hemorrhage / Q000628:therapy*; D013459:Sulfur Hexafluoride / Q000008:administration & dosage*
chemical_list: D005466:Fluorocarbons; D013459:Sulfur Hexafluoride