title: Effects of pentoxifylline on choroidal blood flow in nonproliferative diabetic retinopathy.
abstract: OBJECTIVE
  Diminished blood flow plays an important role in the progression of diabetic retinopathy. Since increased blood viscosity is a contributing factor to hypoperfusion, it was of interest to determine whether therapy intended to decrease blood viscosity and induce vasodilation could increase blood flow in patients with diabetic retinopathy.
  
  
  METHODS
  Ten patients, 4 with nonproliferative diabetic retinopathy and 6 age-matched, nondiabetic controls, were studied by a noninvasive system to index choroidal blood flow. Pentoxifylline was administered daily at an oral dose of 400 mg tid in the diabetic patients for nine months.
  
  
  RESULTS
  The control group had pulse amplitude = 2.87 +/- 0.67 mm Hg with pulsatile choroidal blood flow = 714 +/- 196 microL/minute. Reproducibility studies in the control group (6 patients measured on three separate occasions) demonstrated an intraclass correlation coefficient of reliability, r = 0.83. In the diabetic patients, pulsatile flow = 276 +/- 68 microL/minute, 61% lower than the age-matched nondiabetic subjects (P = 0.003). After nine months of pentoxifylline therapy the diabetic patients had an increase in pulsatile choroidal blood flow to 469 +/- 152 microL/minute (P < 0.002).
  
  
  CONCLUSIONS
  Pentoxifylline therapy brought blood flow levels in the diabetic patients closer to those of the nondiabetic age-matched control population so that following therapy there was no statistically significant difference between the two groups although the former were still lower. The potential efficacy of pentoxifylline in improving ocular blood flow in patients with diabetic retinopathy should be tested in a large controlled clinical trial.
authors.affiliation: Doheny Eye Institute, University of Southern California, Los Angeles.
authors.forename: J
authors.initials: J
authors.lastname: Sebag
authors.forename: M
authors.initials: M
authors.lastname: Tang
authors.forename: S
authors.initials: S
authors.lastname: Brown
authors.forename: A A
authors.initials: AA
authors.lastname: Sadun
authors.forename: M A
authors.initials: MA
authors.lastname: Charles
mesh_terms: D000328:Adult; D002829:Choroid / Q000098:blood supply*; D003930:Diabetic Retinopathy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010431:Pentoxifylline / Q000494:pharmacology*; D010865:Pilot Projects; D011673:Pulsatile Flow / Q000187:drug effects; D012039:Regional Blood Flow / Q000187:drug effects
chemical_list: D010431:Pentoxifylline