title: Corrosion casts of big bubbles formed during deep anterior lamellar keratoplasty.
abstract: OBJECTIVE
  To characterize the walls of big bubbles formed during deep anterior lamellar keratoplasty (DALK) using the corrosion casting technique.
  
  
  METHODS
  Fresh corneoscleral buttons with normal transparency and without any known eye diseases (n = 11) were obtained from 11 human donors. A 20-gauge needle was used to inject a solution of 20 % polyvinyl alcohol (PVA) immediately beneath the corneal endothelium to form big bubbles in eight corneoscleral buttons. In the second experiment on three corneoscleral buttons, a big bubble was first formed by air injection beneath the endothelium. Thereafter, 20 % PVA was injected into the bubble space. Scanning electron microscopy was used to characterize the surfaces of the casts, which replicated the walls of the big bubbles.
  
  
  RESULTS
  A type-1 bubble was formed in all corneas. In one cornea, one type-1 bubble was initially formed centrally, and while it was enlarged, an eccentric type-2 bubble appeared. Scanning electron microscopy showed that the casts of type-1 bubbles had two distinct surfaces. The anterior surface demonstrated several holes or pits, depending on the material used for the bubble formation, whereas the posterior surface exhibited an uneven surface. The anterior and posterior surfaces of the type-2 cast were more or less similar. A communication measuring 531.9 µm in length and 171.4 µm in diameter was found between the two bubbles.
  
  
  CONCLUSIONS
  The corrosion casting technique provides a permanent three-dimensional record of the potential spaces and barriers in the posterior corneal stroma, which explains several features associated with big-bubble DALK.
authors.affiliation: Ophthalmic Research Center, Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Boostan 9 St., Pasdaran Ave., Tehran, 16666, Iran. sepehrfeizi@yahoo.com.
authors.forename: Sepehr
authors.initials: S
authors.lastname: Feizi
authors.affiliation: Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mozhgan Rezaei
authors.initials: MR
authors.lastname: Kanavi
authors.affiliation: Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Davood
authors.initials: D
authors.lastname: Kharaghani
authors.affiliation: Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Sahar
authors.initials: S
authors.lastname: Balagholi
authors.affiliation: Department of Chemistry, Islamic Azad University-Lahijan Branch, Lahijan, Iran.|Bioengineering Department, Biomaterials Laboratory, Politecnico di Milano, Milan, Italy.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Meskinfam
authors.affiliation: Ophthalmic Research Center, Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Boostan 9 St., Pasdaran Ave., Tehran, 16666, Iran.|Central Eye Bank of Islamic Republic of Iran, Tehran, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Javadi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002102:Cadaver; D002648:Child; D003319:Corneal Stroma / Q000473:pathology / Q000601:surgery*; D016039:Corneal Transplantation / Q000009:adverse effects*; D004728:Endothelium, Corneal / Q000473:pathology*; D005260:Female; D006801:Humans; D007640:Keratoconus / Q000175:diagnosis / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: Big bubble; Cornea; Corrosion casts; Deep anterior lamellar keratoplasty; Scanning electron microscopy