Quality of Vision

"Disability glare, defined as glare that disrupts daily activities, occurs rarely, but a few patients find it necessary to curtail night driving, to use sunglasses, or to change their occupation."

Statement on Radial Keratotomy, George O Waring III -1988

"Similarly, persons In occupations with high visual demands such as engineers, surgeons, and writers need careful counseling about expectations and also need to be told that a complication could interfere with their current occupation."

Dr Charles Casebeer, Incisional Keratotomy - 1995


Binocular vision complications after radial keratotomy.

Duling K, Wick B. Source College of Optometry, University of Houston, Texas. Abstract

Radial keratotomy (RK), a popular procedure for reducing myopia, does not always have a successful outcome. Of the adverse effects reported in the literature, there have been few reports of undesirable disturbances of binocular vision. Four representative cases are reviewed which presented clinically with varying binocular problems induced by RK. The treatment considerations and final solutions for each are discussed. In the presence of RK-induced anisometropia, aniseikonia can be a particularly debilitating binocular vision problem for some patients.


Contrast Sensitivity and Glare Disability After Radial Keratotomy 

Alaa A. Ghaith, MD; Jan Daniel, MD; R. Doyle Stulting, MD, PhD; Keith P. Thompson, MD; Michael Lynn, MS

Arch Ophthalmol. 1998;116:12-18. ABSTRACT

Objectives To study the effects of radial keratotomy (RK) and photorefractive keratectomy (PRK) on contrast sensitivity and glare disability using 4 different devices, and to correlate subjective complaints with objective scores of visual performance.

Methods Preoperative contrast sensitivity for 30 eyes undergoing RK and 30 eyes undergoing PRK was compared with contrast sensitivity at 1, 3, and 6 months postoperatively using the CSV 1000, MCT (Multivision Contrast Tester) 8000, and Pelli- Robson chart. The BAT (Brightness Acuity Tester) and MCT 8000 were used to test for daytime and nighttime glare disability, respectively. At 3 and 6 months postoperatively, a questionnaire was administered to assess visual performance subjectively.

Results Contrast sensitivity decreased after RK and PRK up to the sixth postoperative month, while glare disability was significantly increased at 1 month after PRK as determined by the MCT 8000 and the BAT, and at the third and sixth months after RK using the MCT 8000. Compared with RK, PRK significantly decreased contrast sensitivity as measured with the MCT 8000 at all spatial frequencies 1 month postoperatively. No significant difference in visual performance between patients undergoing RK and PRK was observed with the CSV 1000, the Pelli-Robson chart, or the BAT up to 6 months postoperatively. No consistent difference was found between glare disability scores of patients undergoing RK and PRK when measured with the MCT 8000. Subjective reports of problems with night driving and blurring correlated only with glare disability scores of the MCT 80003 months after RK.

Conclusions Both RK and PRK reduce contrast sensitivity and cause glare disability; however, the relative effect is highly dependent on the time postoperative testing is performed and the instrument used for testing. Contrast sensitivity and glare disability, as measured by the instruments used in this study, do not accurately reflect patients' subjective assessment of visual performance in daily life.


Penetrating Keratoplasty for Severe Complications of Radial Keratotomy

Hersh, Peter S. M.D.; Kalevar, V M.D.; Kenyon, Kenneth R. M.D.

Abstract

Severe sight-threatening complications were seen in five eyes of three patients following improperly performed radial keratotomy. All patients exhibited neovascularization of the incision sites, severe stromal scarring or ulceration involving the visual axis, loss of the anterior chamber, and iridocorneal adhesions. These complications necessitated multiple and complex surgical interventions, including penetrating keratoplasty and anterior segment reconstruction. Final visual acuity was decreased to light perception in four eyes while one eye achieved 6/60 vision following repeated penetrating keratoplasty. The success and safety of radial keratotomy rely on careful case selection, appropriate instrumentation, specialized training, and the ability to perform complex secondary procedures to correct surgical complications.

This photo shows how a lot of RK patients see at night.

screen shot 2012-10-18 at med

To See more similar photos, go to visionsimulations.com