title: Purtscher retinopathy: an alternative etiology supported by computer fluid dynamic simulations.
abstract: OBJECTIVE
  To explore an alternative etiology for Purtscher retinopathy by literature review and fluid dynamic computational simulations of wall shear stress (WSS) profiles.
  
  
  METHODS
  Computer simulations were developed, incorporating posterior pole retinal microvascular flow parameters, to demonstrate WSS profiles at 90° and 45° angle artery/arteriolar branching.
  
  
  RESULTS
  Computer simulations reveal WSS profiles dependent on artery/arteriolar branching angles. At high flow rates an area of changed WSS and flow swirling and reversal was noted at the proximal fillet of the 90° arteriolar branching. These changes did not appear at the 45° arteriolar branching until the flow rate was increased an additional 30%.
  
  
  CONCLUSIONS
  Computer simulation data, as well as review of the history and clinical findings of Purtscher and Purtscher-like retinopathy, present evidence that an additional etiology for Purtscher retinopathy may be a rheological event at a retinal posterior pole foci of vascular endothelial dysregulation, followed by downstream endothelin-induced vasculopathy.
authors: Alaska Retinal Associates, Anchorage, Alaska, USA. tom_harrison3@hotmail.com
authors: Thomas J
authors: TJ
authors: Harrison
authors: Cyrus O
authors: CO
authors: Abbasi
authors: Tariq A
authors: TA
authors: Khraishi
mesh_terms: D001783:Blood Flow Velocity; D001790:Blood Physiological Phenomena; D003198:Computer Simulation; D055119:Elastic Modulus / Q000502:physiology; D004730:Endothelium, Vascular / Q000503:physiopathology; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D012039:Regional Blood Flow / Q000502:physiology; D012164:Retinal Diseases / Q000209:etiology* / Q000503:physiopathology; D012171:Retinal Vessels / Q000502:physiology*; D033081:Shear Strength / Q000502:physiology