title: Microcoaxial cataract surgery outcomes: comparison of 1.8 mm system and 2.2 mm system.
abstract: OBJECTIVE
  To compare clinical outcomes of a 1.8 mm and a 2.2 mm microcoaxial cataract surgery system.
  
  
  METHODS
  Department of Ophthalmology and Visual Science, Kangnam St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, Korea.
  
  
  METHODS
  In a prospective study, eyes were randomly selected to have phacoemulsification using a Stellaris system or an Intrepid Infiniti system. The initial incision size was 1.8 mm and 2.2 mm, respectively. Measured intraoperative parameters included phacoemulsification time, mean cumulative dissipated ultrasound energy (CDE), change in incision size at each step of surgery, and total volume of balanced salt solution (BSS) used. The best corrected visual acuity (BCVA), corneal astigmatism, corneal thickness, and endothelial cell count were evaluated preoperatively and postoperatively.
  
  
  RESULTS
  The study evaluated 86 eyes of 78 patients (43 eyes in each group). There were no significant differences in postoperative BCVA, surgically induced astigmatism, or amount of BSS used between the 2 systems (P >.05). However, for high-density cataracts, the 1.8 mm group had a greater change between the initial incision size and the incision size after phacoemulsification (P = .019, nuclear opalescence [NO] NO3; P = .001, NO4), a longer phacoemulsification time (P = .013, NO3), greater mean CDE (P = .005, NO3; P = .001, NO4), and greater corneal endothelial cell loss (P = .003, NO4).
  
  
  CONCLUSIONS
  Both systems were safe and effective in microcoaxial phacoemulsification. The 1.8 mm system performed better with cortical-type cataract and the 2.2 mm system, with high-density nuclear-type cataract.
authors.affiliation: Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Kyung-Min
authors.initials: KM
authors.lastname: Lee
authors.forename: Hyung-Goo
authors.initials: HG
authors.lastname: Kwon
authors.forename: Choun-Ki
authors.initials: CK
authors.lastname: Joo
mesh_terms: D000368:Aged; D001251:Astigmatism / Q000503:physiopathology; D002452:Cell Count; D004728:Endothelium, Corneal / Q000473:pathology; D005260:Female; D006801:Humans; D007431:Intraoperative Complications; D019654:Lens Implantation, Intraocular; D008297:Male; D008866:Microsurgery / Q000379:methods*; D018918:Phacoemulsification / Q000295:instrumentation / Q000379:methods*; D011183:Postoperative Complications; D011446:Prospective Studies; D019591:Pseudophakia / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology; D014945:Wound Healing