title: Visual dysfunction after panretinal photocoagulation in patients with severe diabetic retinopathy and good vision.
abstract: OBJECTIVE
  To compare macular thickness and best-corrected visual acuity (BcVA) before and after panretinal photocoagulation (PRP) in patients with severe diabetic retinopathy and good visual acuity (VA) to identify factors that predict post-operative visual function.
  
  
  METHODS
  Prospective, non-comparative, interventional case series.
  
  
  METHODS
  Sixty-four consecutive patients with severe non-proliferative diabetic retinopathy or with non-high-risk proliferative diabetic retinopathy whose VA was 20/20 or better before PRP were studied. Sixty-four eyes of 64 patients underwent scatter PRP in four sessions every other week. Macular thickness was measured by optical coherence tomography (OCT), and VA was measured before and periodically after PRP.
  
  
  RESULTS
  During the 24-week observation period, patients were classified into three groups according to changes in VA during the post-operative period. In group A, VA was maintained at pre-operative levels in 54 (84%) eyes during the 24 weeks after PRP. In group B, VA initially decreased in three eyes but subsequently recovered to baseline during the observation period; in group C, VA did not recover during follow-up in seven eyes. There was no significant difference in pre-operative foveal thicknesses among the three groups, but parafoveal thickness was <260 mum in group A, ranged from 270 to 280 mum in group B, and was >300 mum in group C.
  
  
  CONCLUSIONS
  For eyes with severe diabetic retinopathy and good VA, PRP did not affect post-operative VA in more than 80% of patients. Patients whose pre-operative parafoveal thickness was >300 mum had a worse visual prognosis.
authors.affiliation: Department of Ophthalmology, NTT East Japan Tohoku Hospital, Miyagi. masahiko@oph.med.tohoku.ac.jp
authors.forename: Masahiko
authors.initials: M
authors.lastname: Shimura
authors.forename: Kanako
authors.initials: K
authors.lastname: Yasuda
authors.forename: Toru
authors.initials: T
authors.lastname: Nakazawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Tamai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003924:Diabetes Mellitus, Type 2 / Q000150:complications; D003930:Diabetic Retinopathy / Q000601:surgery*; D005260:Female; D006801:Humans; D017075:Laser Coagulation; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011446:Prospective Studies; D012160:Retina / Q000473:pathology / Q000601:surgery*; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000209:etiology*; D014792:Visual Acuity