title: Macular dysfunction is common in both type 1 and type 2 diabetic patients without macular edema.
abstract: OBJECTIVE
  To study retinal function in asymptomatic Type 1 and Type 2 diabetic patients with nonproliferative diabetic retinopathy (NPDR) and no clinical signs of diabetic macular edema.
  
  
  METHODS
  Thirty-six consecutive Type 1 and Type 2 diabetic patients with nonproliferative diabetic retinopathy and no diabetic macular edema and 28 healthy controls underwent a complete ophthalmologic examination, including spectral domain optical coherence tomography and microperimetry.
  
  
  RESULTS
  Seventy-one eyes (17 patients with Type 1 and 19 with Type 2 diabetes) were tested, and data from 36 (17 Type 1 and 19 Type 2) eyes were analyzed. Mean best-corrected visual acuity was 0.00 ± 0.01 logMAR and 0.00 ± 0.02 logMAR for Type 1 and Type 2 diabetic patients, respectively (P = 0.075). Mean central foveal thickness was 234.5 ± 13.7 μm and 256.3 ± 12.7 μm for Type 1 and Type 2 diabetic patients, respectively (P = 0.04); the central foveal thickness was statistically different compared with the control groups (P = 0.04 and P = 0.01, respectively). Mean retinal sensitivity was 18.9 ± 0.5 dB and 17.7 ± 0.4 dB for Type 1 and Type 2 diabetic patients, respectively; it was statistically different compared with control groups (P < 0.0001 and P < 0.0001, respectively).
  
  
  CONCLUSIONS
  We demonstrated a significantly reduced sensitivity in both nonproliferative diabetic retinopathy groups without diabetic macular edema compared with healthy controls; this reduction was greater in Type 2 diabetic patients. Central foveal thickness was increased in all diabetic patients compared with healthy controls, despite the absence of diabetic macular edema.
authors: *Department of Ophthalmology, Scientific Institute San Raffaele, University Vita Salute San Raffaele, Milan, Italy; †Department of Ophthalmology, University of Paris Est Creteil, Centre Hospitalier Intercommunal de Creteil, Creteil, France; and ‡Epidemiology Unit, Scientific Institute San Raffaele, Milan, Italy.
authors: Umberto
authors: U
authors: De Benedetto
authors: Giuseppe
authors: G
authors: Querques
authors: Rosangela
authors: R
authors: Lattanzio
authors: Enrico
authors: E
authors: Borrelli
authors: Giacinto
authors: G
authors: Triolo
authors: Gisella
authors: G
authors: Maestranzi
authors: Giliola
authors: G
authors: Calori
authors: Lea
authors: L
authors: Querques
authors: Francesco
authors: F
authors: Bandello
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000503:physiopathology*; D005260:Female; D005584:Fovea Centralis / Q000473:pathology; D006801:Humans; D008266:Macula Lutea / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult