/ /

  • linkedin
  • Increase Font
  • Sharebar

    Postop keratometry not associated with night-vision problems

    Effect was predictor of satisfaction, change in halo; but not glare, starburst, ghosting/double vision

    San Francisco—Postoperative keratometry does not appear to affect patients’ night vision or satisfaction with LASIK, according to Steven Schallhorn, MD. 

    “There are many surgeons who won’t do LASIK if the cornea is made too flat by a myopic procedure,” said Dr. Schallhorn, a clinical professor of ophthalmology at the University of California, San Francisco. “But it has a very small and clinically irrelevant influence.”

    Few studies have investigated the influence of a flat postoperative cornea on visual degradation, and these have reached contradictory results.

    Recent: Exploring SLT efficacy for prior incisional glaucoma surgery

    At the same time, a flatter postoperative keratometry is associated with higher attempted myopic correction, which might confound results.

    To investigate the effect of keratometry on patient’s night vision and satisfaction, Dr. Schallhorn and his colleagues evaluated 8,672 myopic eyes of 4,602 patients from the database of Optical Express in Glasgow, United Kingdom.

    Before surgery, the mean manifest spherical equivalent was -3.72 D, and the mean keratometry (K) value was 43.64.

    The researchers compared these statistics to similar measures 1 month after surgery.

    Related: Using fibrin adhesives to tackle epithelial ingrowth post-LASIK

    “We wanted to look at the early postoperative time period specifically because symptoms are generally worse in the 1-month time period,” Dr. Schallhorn said.

    At 1 month after surgery, 93.7% of eyes were within 0.50 D and 99.1% were within 1 D of emmetropia. Similarly 94.6% of eyes achieved monocular uncorrected-distance visual acuity (UDVA) of 20/20 or better, and 98.3% achieved binocular uncorrected distance visual acuity of 20/20.

    At the same time, 48.7% of the eyes had a flat corneal meridian (Kmin) of 40.0 D or less, and 6.0% had a Kmin of 37 D or less.

    Overall, 95.6% of the patients said they were satisfied or very satisfied with the procedure, while 2.6% were neither satisfied nor dissatisfied and 1.8% were dissatisfied.

    Related: Tablet-based tests putting detection of glaucoma at hand

    The mean scores for postoperative night-vision phenomena were 1.96 for glare, 1.89 for halo, 1.94 for starburst, and 1.39 for ghosting and double vision.

    Postoperative keratometry was a small-but-statistically-significant predictor of patient-reported satisfaction, and the change in halo reports. But it accounted for only 0.3% of the variance in patient satisfaction and 0.1% of the variance in halo complaints.

    In addition, it was not a significant predictor of changes in reports of glare, starburst, ghosting, or double vision.

    Subcategory analysis

    New Call-to-action

    0 Comments

    You must be signed in to leave a comment. Registering is fast and free!

    All comments must follow the ModernMedicine Network community rules and terms of use, and will be moderated. ModernMedicine reserves the right to use the comments we receive, in whole or in part,in any medium. See also the Terms of Use, Privacy Policy and Community FAQ.

    • No comments available

    Poll

    View Results