title: Residual internal limiting membrane after epiretinal membrane peeling: results of the Pan-American Collaborative Retina Study Group.
abstract: OBJECTIVE
  To determine the degree of residual internal limiting membrane (ILM) after idiopathic epiretinal membrane (ERM) peeling and the usefulness of staining with brilliant blue G.
  
  
  METHODS
  A prospective, multicenter, observational study of 98 eyes undergoing pars plana vitrectomy and membrane peeling for idiopathic ERM. All eyes underwent core vitrectomy (20, 23, or 25 gauge) followed by intravitreal triamcinolone to verify that the posterior hyaloid had been removed. Brilliant blue G (0.2 mL of 0.25 mg/mL) was injected into the vitreous cavity and washed out immediately. The ERM was peeled and then the surgeon observed and recorded the characteristics of the underlying ILM. The posterior pole was restained with brilliant blue G (0.2 mL of 0.25 mg/mL), and the same observations on the characteristics of the ILM were recorded. Peeling of the remaining ILM was performed. The main outcome measured was the status of the ILM after ERM peel. Secondary outcomes included best-corrected visual acuity and central macular thickness at 6 months postoperatively.
  
  
  RESULTS
  After ERM peel, all of the eyes had residual ILM. In 74 eyes, the ILM was present and damaged, whereas in 24 eyes, the ILM was present and undamaged. In 37 eyes, the operating surgeon was unable to determine the status of the ILM before brilliant blue G staining. At 6 months, the logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.75 ± 0.39 at baseline to 0.31 ± 0.26 (P < 0.0001). The central macular thickness also improved from 460 ± 91 μm at baseline to 297 ± 102 μm (P < 0.003).
  
  
  CONCLUSIONS
  Internal limiting membrane is frequently still present after ERM peeling. Staining with brilliant blue G facilitates its identification.
authors.affiliation: *Fundación Oftalmológica Los Andes, Santiago, Chile; †Instituto de Cirugía Ocular, San José, Costa Rica; ‡Department of Ophthalmology, University of Puerto Rico, San Juan, Puerto Rico; §Department of Ophthalmology, Universidad Austral, Buenos Aires, Argentina; ¶Instituto Oftalmológico de Valencia, Valencia, Spain; **Vitreoretinal Surgery Unit, Brazilian Institute of Fighting Against Blindness, Assis/Presidente Prudente, Sao Paulo, Brazil; ††The King Khaled Eye Specialist Hospital, Riyadh, Kingdom of Saudi Arabia; ‡‡Wilmer Eye Institute, The Johns Hopkins University, Baltimore, Maryland; and §§Vitreoretinal Surgery, Universidade Federal de Sao Paulo, Sao Paulo, Brazil.
authors.forename: Cristian
authors.initials: C
authors.lastname: Carpentier
authors.forename: Mario
authors.initials: M
authors.lastname: Zanolli
authors.forename: Lihteh
authors.initials: L
authors.lastname: Wu
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Sepulveda
authors.forename: Maria H
authors.initials: MH
authors.lastname: Berrocal
authors.forename: Mario
authors.initials: M
authors.lastname: Saravia
authors.forename: Manuel
authors.initials: M
authors.lastname: Diaz-Llopis
authors.forename: Roberto
authors.initials: R
authors.lastname: Gallego-Pinazo
authors.forename: Luis
authors.initials: L
authors.lastname: Filsecker
authors.forename: Juan I
authors.initials: JI
authors.lastname: Verdaguer-Diaz
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Milan-Navarro
authors.forename: J Fernando
authors.initials: JF
authors.lastname: Arevalo
authors.forename: Mauricio
authors.initials: M
authors.lastname: Maia
mesh_terms: D001485:Basement Membrane / Q000473:pathology; D019773:Epiretinal Membrane / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D007202:Indicators and Reagents; D008266:Macula Lutea / Q000473:pathology; D011446:Prospective Studies; D012394:Rosaniline Dyes; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology; D014821:Vitrectomy
chemical_list: D007202:Indicators and Reagents; D012394:Rosaniline Dyes; C004692:coomassie Brilliant Blue