title: Assessment of macular function by multifocal electroretinography following epiretinal membrane surgery with indocyanine green-assisted internal limiting membrane peeling.
abstract: OBJECTIVE
  To evaluate the changes in macular function and potential retinal toxicity in epiretinal membrane (ERM) surgery with indocyanine green (ICG)-assisted internal limiting membrane (ILM) peeling using multifocal electroretinography (mfERG).
  
  
  METHODS
  Thirteen eyes of 13 patients were randomly assigned to have ERM surgery with ILM peeling using 0.5 mg/ml or 1.25 mg/ml ICG staining. Patients were examined at baseline and at 3 and 6 months postoperatively. The postoperative mfERG N1 and P1 response amplitudes and peak latencies of various ring eccentricities were assessed and compared with baseline to determine any serial changes.
  
  
  RESULTS
  After surgery, the median best-corrected visual acuity improved from 20/70 at baseline to 20/30 at 6 months postoperatively (Wilcoxon signed-ranks test, P=0.004). At 3 months postoperatively, the 0.5 mg/ml group showed no significant changes in N1 and P1 response amplitudes and peak latencies, whereas the 1.25 mg/ml ICG group showed significant reductions in N1 and P1 response amplitudes compared with baseline. No significant changes in mfERG responses were observed in either group at 6 months after surgery.
  
  
  CONCLUSIONS
  Our mfERG findings suggested that the use of a higher concentration of ICG for ILM staining might result in transient retinal functional impairment postoperatively. The lowest possible concentration of ICG should be used intraoperatively to minimize potential retinal toxicity.
authors.affiliation: Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, 147 K Argyle Street, Kowloon, Hong Kong, People's Republic of China. tyylai@netvigator.com
authors.forename: Timothy Y Y
authors.initials: TY
authors.lastname: Lai
authors.forename: Alvin K H
authors.initials: AK
authors.lastname: Kwok
authors.forename: Amy W H
authors.initials: AW
authors.lastname: Au
authors.forename: Dennis S C
authors.initials: DS
authors.lastname: Lam
mesh_terms: D000368:Aged; D001485:Basement Membrane / Q000473:pathology / Q000601:surgery*; D004396:Coloring Agents / Q000009:adverse effects; D004596:Electroretinography / Q000187:drug effects; D019773:Epiretinal Membrane / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007208:Indocyanine Green / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000187:drug effects / Q000503:physiopathology*; D013194:Staining and Labeling / Q000379:methods; D014792:Visual Acuity
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green