title: Comparison of surgically induced astigmatism after coaxial phacoemulsification through 1.8 mm microincision and bimanual phacoemulsification through 1.7 mm microincision.
abstract: OBJECTIVE
  To compare surgically induced astigmatism (SIA) after coaxial 1.8 mm microincision cataract surgery (MICS) and bimanual 1.7 mm MICS calculated with 3 mathematical methods.
  
  
  METHODS
  Department of Ophthalmology, Medical University of Lodz, Lodz, Poland.
  
  
  METHODS
  Study comprised a nonrandomized prospective consecutive series of 58 eyes of 58 patients who had uneventful coaxial MICS with implantation of an Akreos MI60 foldable intraocular lens (IOL) using a 1.8 mm temporal clear corneal incision. Fifty eyes of 50 patients who had uneventful bimanual MICS through a 1.7 mm clear corneal incision for a sleeveless phaco tip and a 1.5 mm side port for an irrigating chopper with implantation of an Acri.Smart 48S foldable IOL served as a comparison group. All surgery was performed by 2 experienced surgeons. Surgically induced astigmatism was calculated using 3 methods.
  
  
  RESULTS
  The patients were examined preoperatively and 2 weeks to 1 month postoperatively. No intraoperative or postoperative complications were seen in any patient. The corrected distance visual acuity improved significantly in both groups after surgery (P<.01); the visual outcomes were not significantly different (P>.05). In vector analysis, the mean SIA was 0.42 +/- 0.29 in the coaxial MICS group and 0.50 +/- 0.24 in the bimanual group; the difference was not statistically significant (P>.05). In vector decomposition, the mean SIA (C90) coaxial MICS group was 0.23 +/- 0.29 in the coaxial MICS group and 0.23 +/- 0.22 in the bimanual MICS group; the difference was not significant. Using the Naeser method, DeltaKP-90 was calculated, amounting to 0.05 +/- 0.44 in the coaxial MICS group and -0.04 +/- 0.42 in the bimanual MICS group; the difference was not significant.
  
  
  CONCLUSIONS
  The amount of SIA induced by bimanual MICS and coaxial MICS phacoemulsification was very small. The bimanual MICS induced a slightly higher degree of SIA; however, according to all methods of SIA analysis, there was no significant difference in the mean SIA induced by both techniques.
authors.affiliation: Department of Ophthalmology, Medical University of Lodz, Lodz, Poland. michalwilczynski@wp.pl
authors.forename: Michal
authors.initials: M
authors.lastname: Wilczynski
authors.forename: Ewa
authors.initials: E
authors.lastname: Supady
authors.forename: Loba
authors.initials: L
authors.lastname: Piotr
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Synder
authors.forename: Dorota
authors.initials: D
authors.lastname: Palenga-Pydyn
authors.forename: Wojciech
authors.initials: W
authors.lastname: Omulecki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000209:etiology*; D002386:Cataract / Q000150:complications; D003315:Cornea / Q000601:surgery; D005260:Female; D006801:Humans; D065347:Hypromellose Derivatives; D019654:Lens Implantation, Intraocular; D008297:Male; D008747:Methylcellulose / Q000008:administration & dosage / Q000031:analogs & derivatives; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged; D018918:Phacoemulsification / Q000009:adverse effects*; D011446:Prospective Studies; D012029:Refraction, Ocular / Q000502:physiology; D055675:Viscosupplements / Q000008:administration & dosage; D014792:Visual Acuity / Q000502:physiology
chemical_list: D055675:Viscosupplements; D065347:Hypromellose Derivatives; D008747:Methylcellulose