title: Improvement of visual acuity in patients suffering from diabetic retinopathy after membrane differential filtration: a pilot study.
abstract: BACKGROUND
  Membrane differential filtration is an extracorporeal treatment procedure which eliminates high molecular weight proteins and lipids from the blood. This pilot study was initiated to investigate the short-term effects on blood rheology and visual function in patients suffering from diabetic retinopathy.
  
  
  METHODS
  Six patients with non-proliferative diabetic retinopathy, clinically significant macular edema (five patients, nine eyes) and inactive proliferative diabetic retinopathy (one patient, one eye) underwent a single treatment with a hollow fiber secondary plasma filter. The main parameter measured was visual acuity prior to and after treatment. Biochemical and rheological parameters (whole blood and plasma viscosity, and erythrocyte aggregation) were also measured. The mean follow-up was 25 (range 4-90) days after treatment.
  
  
  RESULTS
  The mean improvement of visual acuity was 1.4 lines (SD 0.8 lines, p = 0.002) 24 h after therapy. This remained stable during the follow-up period. The rheological measures were significantly lowered. A significant reduction of total protein, fibrinogen, IgG, IgM, IgA, alpha-2-macroglobulin, total cholesterol, LDL and HDL was found.
  
  
  CONCLUSIONS
  This study demonstrates the rheological impact of membrane differential filtration. It was shown that rheological changes correlated with clinical improvement in patients suffering from diabetic retinopathy with clinically significant macular edema.
authors.affiliation: Department of Ophthalmology, University of Cologne, Germany.
authors.forename: R A
authors.initials: RA
authors.lastname: Widder
authors.forename: R
authors.initials: R
authors.lastname: Brunner
authors.forename: P
authors.initials: P
authors.lastname: Walter
authors.forename: C
authors.initials: C
authors.lastname: Lüke
authors.forename: K U
authors.initials: KU
authors.lastname: Bartz-Schmidt
authors.forename: K
authors.initials: K
authors.lastname: Heimann
authors.forename: H
authors.initials: H
authors.lastname: Borberg
mesh_terms: D000368:Aged; D001809:Blood Viscosity; D003930:Diabetic Retinopathy / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006440:Hemofiltration; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D010974:Platelet Aggregation; D014792:Visual Acuity / Q000502:physiology*