title: Enhanced depth imaging optical coherence tomography in type 2 diabetes.
abstract: OBJECTIVE
  To investigate the changes in macular choroidal thickness in eyes with various stages of diabetic retinopathy, using enhanced depth imaging optical coherence tomography (EDI OCT).
  
  
  METHODS
  Sixty-three consecutive diabetic patients--who presented without diabetic retinopathy (NDR); with diabetic retinopathy (nonproliferative diabetic retinopathy [NPDR]) and no clinically significant macular edema (CSME-); or with NDPR and clinically significant macular edema (CSME+)--underwent EDI OCT. Twenty-one age- and sex-matched healthy subjects (21 eyes) also underwent EDI OCT.
  
  
  RESULTS
  A total of 63 eyes of 63 consecutive diabetic patients (26 female [41.2%]; mean age 65 ± 9 years, range 48-83 years) were included in the analysis. Mean best-corrected visual acuity was 0.13 ± 0.25 LogMAR (range 0-1). Mean CMT was 272.5 ± 16.2 μm in 21 NDR eyes, 294.5 ± 23.5 μm in 21 NPDR/CSME- eyes, and 385.6 ± 75.1 μm in 21 NPDR/CSME+ eyes. There was no difference in mean subfoveal choroidal thickness among each diabetic group (238.4 ± 47.9 μm [NDR], 207.0 ± 55.9 μm [NPDR/CSME-], 190.8 ± 48.4 μm [NPDR/CSME+]; P = 0.23). The mean subfoveal choroidal thickness was significantly reduced in each diabetic group compared with the control group (309.8 ± 58.5 μm, P < 0.001).
  
  
  CONCLUSIONS
  In diabetic eyes, there is an overall thinning of the choroid on EDI OCT. A decreased choroidal thickness may lead to tissue hypoxia and consequently increase the level of VEGF, resulting in the breakdown of the blood-retinal barrier and development of macular edema.
authors.affiliation: Department of Ophthalmology, University Vita Salute San Raffaele, Milan, Italy. giuseppe.querques@hotmail.it
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Querques
authors.forename: Rosangela
authors.initials: R
authors.lastname: Lattanzio
authors.forename: Lea
authors.initials: L
authors.lastname: Querques
authors.forename: Claudia
authors.initials: C
authors.lastname: Del Turco
authors.forename: Raimondo
authors.initials: R
authors.lastname: Forte
authors.forename: Luisa
authors.initials: L
authors.lastname: Pierro
authors.forename: Eric H
authors.initials: EH
authors.lastname: Souied
authors.forename: Francesco
authors.initials: F
authors.lastname: Bandello
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002829:Choroid / Q000473:pathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000175:diagnosis*; D003930:Diabetic Retinopathy / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement; D008269:Macular Edema / Q000175:diagnosis / Q000209:etiology; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012160:Retina / Q000473:pathology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence / Q000379:methods*