title: Association between surgically-induced astigmatism and cataract incision size in the early postoperative period.
abstract: One hundred sixteen eyes with cataracts were prospectively randomized into four surgical groups. Silicone and polymethylmethacrylate (PMMA) intraocular lenses were implanted into the posterior chamber of these eyes through 4-, 6-, or 11-millimeter incisions by one surgeon. Surgically-induced astigmatism was evaluated in terms of: (1) the proportion of eyes achieving a refractive cylinder of 1.5 or less, without regard to axis; and (2) the induced cylinder, with regard to axis, using vector analysis. One week postoperatively, the eyes with a 4-millimeter incision had a significantly lower mean induced cylinder than those with larger incisions (P = .019); and all three phacoemulsification groups had a significantly higher proportion of eyes with a cylinder of 1.5 or less than the nuclear expression group (P < .01). One month postoperatively, the 4-millimeter-incision group had a significantly lower mean induced cylinder (P = .044) as well as a significantly higher proportion of eyes with a cylinder of 1.5 or less, than the larger-incision groups (P = .05). Three months postoperatively, no value of any parameter in any group differed significantly from that of that parameter in any other group.
authors.affiliation: Department of Ophthalmology, Hahnemann University Hospital, Philadelphia, Pa.
authors.forename: M M
authors.initials: MM
authors.lastname: Leen
authors.forename: C C
authors.initials: CC
authors.lastname: Ho
authors.forename: M
authors.initials: M
authors.lastname: Yanoff
mesh_terms: D000368:Aged; D001251:Astigmatism / Q000209:etiology*; D002387:Cataract Extraction / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D007910:Lenses, Intraocular; D008297:Male; D020366:Methylmethacrylate; D008768:Methylmethacrylates; D011184:Postoperative Period; D011446:Prospective Studies; D012029:Refraction, Ocular; D012826:Silicone Elastomers; D014792:Visual Acuity
chemical_list: D008768:Methylmethacrylates; D012826:Silicone Elastomers; D020366:Methylmethacrylate