title: Impact of crystalline lens opacification on effective phacoemulsification time in femtosecond laser-assisted cataract surgery.
abstract: OBJECTIVE
  To compare effective phacoemulsification time in cataract surgery performed by manual phacoemulsification vs femtosecond laser-assisted lens fragmentation.
  
  
  METHODS
  Retrospective, consecutive, nonrandomized, comparative case series.
  
  
  METHODS
  The setting was the Department of Ophthalmology, Goethe-University, Frankfurt, Germany. The study population included 150 eyes of 86 patients with senile cataract. In the intervention, 88 eyes (group 1) underwent femtosecond laser-assisted surgery (corneal incisions, capsulotomy, lens fragmentation) using the LenSx platform (Alcon) and residual lens work-up with pulsed ultrasound energy (Infiniti Vision System; Alcon). In 62 eyes (group 2), complete cataract removal was performed with phacoemulsification only, using pulsed ultrasound energy with the same device (Infiniti). Nucleus staging (Pentacam nucleus staging; PNS) was evaluated using Pentacam HR (Oculus); endothelial cell density was measured using specular microscopy (NonCon Robo). The main outcome measures were as follows. Mean preoperative PNS staging was assessed using an automatic ordinal scaling (PNS-O, grades 0-5) and a manually defined density grid derived from Scheimpflug imaging (PNS-P [%]). Effective phacoemulsification time and endothelial cell loss were evaluated in both groups.
  
  
  RESULTS
  Preoperative PNS-O and PNS-P showed no significant difference between groups (P = 0.267). Overall mean effective phacoemulsification time was significantly lower in group 1 (1.58 ± 1.02 seconds) compared to 4.17 ± 2.06 seconds in group 2 (P = 0.001). Effective phacoemulsification time was significantly lower in group 1 for all PNS-O stages (P < 0.001). With increasing preoperative PNS-P, effective phacoemulsification time increased in both groups; however, this gain was noticeably, but not significantly, lower in group 2. Endothelial cell loss was significantly lower in group 1 (P = 0.02).
  
  
  CONCLUSIONS
  Femtosecond laser-assisted cataract surgery allows a significant reduction in effective phacoemulsification time, which correlates positively with the preoperative lens opacity.
authors.affiliation: Department of Ophthalmology, Goethe-University Frankfurt am Main, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany; Department of Ophthalmology, Ludwig-Maximilians-University Munich, Mathildenstrasse 8, 80336 Munich, Germany.
authors.forename: Wolfgang J
authors.initials: WJ
authors.lastname: Mayer
authors.affiliation: Department of Ophthalmology, Goethe-University Frankfurt am Main, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
authors.forename: Oliver K
authors.initials: OK
authors.lastname: Klaproth
authors.affiliation: Department of Ophthalmology, Goethe-University Frankfurt am Main, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
authors.forename: Fritz H
authors.initials: FH
authors.lastname: Hengerer
authors.affiliation: Department of Ophthalmology, Goethe-University Frankfurt am Main, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany. Electronic address: kohnen@em.uni-frankfurt.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kohnen
mesh_terms: D000368:Aged; D002386:Cataract / Q000145:classification*; D055954:Corneal Endothelial Cell Loss; D005260:Female; D006801:Humans; D007431:Intraoperative Complications; D053685:Laser Therapy; D007908:Lens, Crystalline / Q000473:pathology*; D008297:Male; D018918:Phacoemulsification / Q000379:methods*; D012189:Retrospective Studies; D013997:Time Factors