title: Morphometric changes of corneal endothelial cells following intracameral air for micro perforation of the Descemet Membrane during big-bubble deep anterior lamellar keratoplasty.
abstract: OBJECTIVE
  The aim of this study was to assess the effect of intracameral air on the endothelial cell morphometrics.
  
  
  METHODS
  This is a retrospective controlled interventional cohort study of 26 patients (18 males and 8 females) who underwent unilateral deep anterior lamellar keratoplasty (DALK) for moderate keratoconus. The DALK patients were divided into two groups: a treatment group (14), which had micro perforations of the Descemet Membrane (DM) intraoperatively and received intracameral air at the end of the surgery; and an independent control group (12), which had no micro perforation and thus no intracameral air was injected. Postoperative best corrected visual acuity (BCVA), sphere, cylinder, spherical equivalent (SEQ), central corneal thickness, and endothelial cell morphometric features consisted of the endothelial cell density (ECD), polymegathism, and pleomorphism were compared between treatment and control groups.
  
  
  RESULTS
  The mean BCVA was 0.36 ± 0.36 logMAR in the treatment group and 0.17 ± 0.11 logMAR in the control group (p = 0.081), and the mean corneal thickness was 507.86 ± 62.69 μm in the treatment group and 525.67 ± 37.54 μm in the control group air (p = 0.399). Furthermore, the mean sphere was -5.14 ± 4.17D and -1.02 ± 3.29D, the mean cylinder was -3.16 ± 2.20D and -2.88 ± 1.21D, and the mean SEQ was -6.72 ± 4.66D and -2.46 ± 3.14D and in the treatment and control groups respectively (p = 0.011, 0.693, and 0.013). As to morphometric features, the mean ECD was 2176.76 ± 549.18 cell/mm(2) and 2257.30 ± 436.12 cell/mm(2) in the treatment and control groups respectively (p = 0.686), and the mean pleomorphism 0.48 ± 0.09 and 0.54 ± 0.10 in the treatment and control groups respectively (p = 0.139). In contrast, the mean polymegathism was 0.37 ± 0.06 and 0.31 ± 0.05 in the treatment and control groups respectively (p = 0.009).
  
  
  CONCLUSIONS
  The presence of air inside the anterior chamber for a short term may not cause further endothelial cell loss and can be safely performed to prevent postoperative Descemet Membrane detachment in case of micro perforations.
authors.affiliation: Dhahran Eye Specialist Hospital, P.O. Box: 39455, Dhahran, Eastern Province 31942, Saudi Arabia.
authors.forename: Ashbala
authors.initials: A
authors.lastname: Khattak
authors.affiliation: Optometry and Investigation Services, Dhahran Eye Specialist Hospital (DESH), P.O. Box: 39455, Dhahran, Eastern Province 31942, Saudi Arabia.
authors.forename: Fouad R
authors.initials: FR
authors.lastname: Nakhli
authors.affiliation: University of Dammam, Dammam, Saudi Arabia.
authors.forename: Hussam Mohammad
authors.initials: HM
authors.lastname: Abdullatif Abouollo
keywords: Endothelial cell density; Keratoconus; Keratoplasty; Pleomorphism; Polymegathism