title: Residual cellular proliferation on the internal limiting membrane in macular pucker surgery.
abstract: OBJECTIVE
  To provide pathology data on the completeness of epiretinal membrane (ERM) removal with and without internal limiting membrane (ILM) peeling.
  
  
  METHODS
  Twenty-two patients with idiopathic ERM formation underwent vitrectomy with ERM removal and subsequent staining of the vitreomacular interface with brilliant blue. If the ILM was still present after ERM removal, it was peeled off. Both ERM and ILM specimens were harvested in different containers and prepared for flat-mount phase-contrast and interference microscopy, immunocytochemistry, and transmission electron microscopy.
  
  
  RESULTS
  In 14 patients (64%), the ILM was still present at the macula after ERM removal. On average, 20% (range, 2-51%) of the total cell count was left behind at the ILM if the ERM was removed only. There were mainly glial cells on the ILM, and few hyalocytes. In nine eyes, the cells were forming cell clusters. In 8 patients (36%), both ERM and ILM were removed together. Electron microscopy showed cellular proliferation directly attached to the ILM in these eyes, whereas in the sequentially peeled group, there was collagen interposed between the ERM and the ILM. Surgical ERM removal resulted in splitting of the vitreous cortex in these eyes, leaving the ILM with residual cells behind.
  
  
  CONCLUSIONS
  Simple ERM removal results in sufficient separation of fibrocellular tissue in one third of cases, only. In 2 of 3 patients with idiopathic ERM, the vitreous cortex splits when the ERM is removed, leaving an average of 20% of the total cell count behind on the ILM. As these cells are capable of proliferation and causing ERM recurrence, staining of the ILM with subsequent removal seems beneficial in macular pucker surgery.
authors: Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. arnd.gandorfer@med.uni-muenchen.de
authors: Arnd
authors: A
authors: Gandorfer
authors: Christos
authors: C
authors: Haritoglou
authors: Renate
authors: R
authors: Scheler
authors: Ricarda
authors: R
authors: Schumann
authors: Fei
authors: F
authors: Zhao
authors: Anselm
authors: A
authors: Kampik
mesh_terms: D000368:Aged; D001485:Basement Membrane / Q000473:pathology; D049109:Cell Proliferation; D019773:Epiretinal Membrane / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D012163:Retinal Detachment / Q000473:pathology* / Q000601:surgery*; D014821:Vitrectomy / Q000379:methods