title: Microincision versus Standard Corneal Incision Phacoemulsification: Visual Outcome.
abstract: OBJECTIVE
  To compare the visual outcome of microincision (2.2 mm) with standard (2.75 mm) corneal incision phacoemulsification.
  
  
  METHODS
  In this prospective, randomized comparative study, patients with senile cataract and less than 1 diopter (D) of astigmatism were divided into two groups. Group 1 included patients undergoing phacoemulsification with 2.2 mm clear corneal incision and group 2 included those undergoing phacoemulsification with 2.75 mm incision. The steep axis measured on keratometry was marked preoperatively. Phacoemulsification was performed through clear corneal incision on this steep axis. Assessment of visual acuity (distance and near), keratometry, keratometric cylinder, contrast sensitivity by Functional Acuity Contrast Test, and surgically induced astigmatism (SIA) was performed at 1 day, 1 week, and 1, 3, and 6 months.
  
  
  RESULTS
  Fifty eyes of 50 patients were included in the study (29 were male). There were 25 patients in each group. The mean (±SD) SIA calculated by vector analysis method (Holladay-Cravy-Koch) using keratometry value, at the end of 6 months, was 0.54 (±0.18) D and 0.58 (±0.14) D in groups 1 and 2, respectively (p = 0.27). No significant differences were found in the distance and near uncorrected visual acuity, mean keratometry, keratometric cylinder, contrast sensitivity, and SIA at any follow-up visit between two groups.
  
  
  CONCLUSIONS
  In patients with less than 1 D astigmatism undergoing phacoemulsification, both 2.2-mm and 2.75-mm clear corneal incisions result in similar postoperative visual outcome in terms of SIA, keratometry, and contrast sensitivity.
authors.affiliation: *MD †MS Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India (VKJ, SK, MV); Department of Ophthalmology, All India Institute of Medical Sciences, Raipur, India (VKJ); Stanley M. Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska (AA); and Post Graduate Institute of Medical Education and Research, Chandigarh, India (JK, JR).
authors.forename: Vaibhav K
authors.initials: VK
authors.lastname: Jain
authors.forename: Sudarshan
authors.initials: S
authors.lastname: Khokhar
authors.forename: Aniruddha
authors.initials: A
authors.lastname: Agarwal
authors.forename: Murugesan
authors.initials: M
authors.lastname: Vanathi
authors.forename: Jaya
authors.initials: J
authors.lastname: Kaushik
authors.forename: Jagat
authors.initials: J
authors.lastname: Ram
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000503:physiopathology; D015350:Contrast Sensitivity / Q000502:physiology; D003315:Cornea / Q000503:physiopathology / Q000601:surgery*; D019781:Corneal Topography; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular; D008297:Male; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged; D018918:Phacoemulsification / Q000379:methods*; D011183:Postoperative Complications; D011446:Prospective Studies; D014792:Visual Acuity / Q000502:physiology