title: Detection of early functional changes in diabetic retina using slow double-stimulation mfERG paradigm.
abstract: Aim Diabetes mellitus (DM) is a systemic disease with insufficient secretion of insulin or poor response to insulin. This typically causes poor control of blood glucose level leading to a range of complications. Early detection of the retinal function alteration in DM is needed.  Methods A newly modified paradigm-slow double-stimulation multifocal electroretinogram (mfERG)-was introduced to measure early changes of retinal function in DM and to investigate changes in the adaptation mechanisms in the diabetic retina. The mfERG was measured by using a slow double-stimulation mfERG paradigm (M(1)M(2)OOO).  Results The m1 amplitude of M(1) stimulation from diabetic subjects was significantly reduced in ring 1 in contrast to that of a control group. The m2 amplitude of M(2) stimulation from diabetic subjects was also significantly reduced in ring 1 and 2 as compared with those of the control group. The m1/m2 ratio which minimises intersubject variation shows a reasonable differentiation between the control and diabetic groups. There was a significant increase in the amplitude ratio from diabetic subjects in ring 2 and 3 as compared with those of the control group.  Conclusions The present findings suggest that the new mfERG paradigm is a fast and sensitive test for the detection of early functional changes in the diabetic retina.
authors.affiliation: School of Optometry, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, PR China. henryhl.chan@polyu.edu.hk
authors.forename: Henry Ho-lung
authors.initials: HH
authors.lastname: Chan
authors.forename: Patrick Ho-wai
authors.initials: PH
authors.lastname: Chu
authors.forename: Jenny Chun-yee
authors.initials: JC
authors.lastname: Lung
authors.forename: Wing-cheung
authors.initials: WC
authors.lastname: Ho
authors.forename: Patrick Wai-ki
authors.initials: PW
authors.lastname: Ting
authors.forename: Rita Wing-man
authors.initials: RW
authors.lastname: Sum
authors.forename: Yiu-fai
authors.initials: YF
authors.lastname: Ng
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D003930:Diabetic Retinopathy / Q000175:diagnosis* / Q000209:etiology; D042241:Early Diagnosis; D004596:Electroretinography / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D010775:Photic Stimulation / Q000379:methods; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted