Eyes and Vision
Visual Function and Disorders
Best Corrected Distant Visual Acuity
The LEO should have distance-corrected visual acuity of 20/20 or better binocularly, with at least 20/40 in each eye.1 Individuals who cannot be corrected to 20/20 in each eye, must be evaluated by an ophthalmologist or optometrist.
Uncorrected Distant Visual Acuity
LEOs who wear soft contact lenses should have no uncorrected distant visual acuity recommendation. For LEOs who wear glasses or hard contacts, uncorrected distant visual acuity should be 20/100 or better binocularly, without any further recommendation for single eye visual acuity.8,9
Best Corrected Near Visual Acuity
LEOs require 20/40 corrected visual acuity in the better eye to perform near vision dependent job functions. If near vision cannot be corrected to 20/40 in both eyes, an evaluation should be performed (see Appendix A).
Uncorrected Near Visual Acuity
There are no recommendations for uncorrected near visual acuity.
Refractive surgery can be a reasonable option for LEOs with refractive error.10,11 For LEOs who undergo refractive surgery to correct refractive error, the operating surgeon should complete the surgical report form (see Appendix B), describing the surgery and post-operative course. This form will provide sufficient information to the police physician to enable evaluation of the LEO for duty status.12 LEOs must still meet the visual acuity standards in this guidance; occasionally, glasses or other corrective lenses may be necessary.
Post-operatively, the LEO should present a stable refraction (no more than 1/2 dioter of change between documented refractions at least 2 weeks apart). In addition, for unrestricted duty, the LEO should not have any of the following:
- use of steroid drops;
- significant haze (+2 or less is acceptable);
- glare, halos, starbursts, and ghosting (monocular diplopia);
- microstriae that affect vision;
- dryness that affects vision; and
- loose epithelium, diffuse lamellar keratitis (DLK), and/or active infection;
Refractive surgery patients should have periodic refractions and follow-up. A discussion of radial keratotomy, PRK, LASIK and LASEK issues, and ongoing monitoring and surveillance is found in Appendix A.
Orthokeratology is not endorses as a suitable means for refractive correction for LEOs. A more detailed discussion of orthokeratology is found in Appendix A.
LEOs should have normal color vision or only mild color vision deficiency (i.e., adequate color vision). For LEOs who fail a screening test for normal color vision, it is recommended that they be tested using a procedure that provides a measure of the degree of impairment (see Appendix A for details) to ensure their color discrimination is adequate.
Because of the rarity of tritan (blue-yellow) deficiencies, it is the consensus of the Task Group that routine testing for this impairment is not necessary. Use of tinted contact lenses is NOT a suitable accommodation for impaired color vision (see Appendix A for a discussion of color vision).
Using common testing equipment, the Task Force considered the following common criteria as appropriate screening for adequate color vision:
- Passing of a standard test for color vision (see Appendix A)
- No errors or errors only on the mild classification plates on the Hardy, Rand and Ritter Plates, 4th Edition
- No major (diametrical) crossings on a Farnsworth D-15 test
The LEO’s horizontal field should be at least 120º in each eye.1
LEOs with visual field deficiencies need additional evaluation. Formal visual field testing should be performed on all LEOs with a history of eye disease (e.g., glaucoma, retinal diseases – not simple refractive errors) and in those who cannot be corrected to 20/20 in both eyes.
LEOS with eye diseases that are progressive (e.g., glaucoma) should have formal visual testing annually. See discussion on visual fields in Appendix A.
LEOs should have binocular vision (see Appendix A for details).
LEOs with anisometropia should meet the visual acuity requirements previously listed in this chapter (see Appendix A for details).
Surgically Induced Monovision
Surgically induced monovision is a deliberate induction of anisometropia so that one eye is corrected for clearer distance vision and one eye is corrected for clearer near vision. It is not recommended that LEOs undergo surgery to create monovision as it is likely to create more visual problems than it solves. All LEOs should still meet the visual acuity standards listed in this document. It is likely that those LEOs with surgical monovision will require the wearing of corrective lenses to meet those standards (see Appendix A for details).
Stereopsis (the ability to use two eyes to fuse an image) is not critical for most LEO positions and no standard is recommended. An agency may have unique job functions that require a particular performance level, and if so, should identify those functions and link them with an appropriate standard (see Appendix A for further discussion).13
Night Blindness (Nyctalopia)
Night blindness (nyctalopia) is the inability to see well at night or in poor light. It is not a disease in of itself, but rather a symptom of a possible underlying problem.14 LEOs who complain of difficulty seeing at night or with glare or fog or haze should be referred to an ophthalmologist or optometrist for a comprehensive eye exam that includes contrast sensitivity testing, plus detailed evaluation of the retina, lens, and cornea. If all testing is normal, it should be reported that no objective evidence exists to substantiate the complaints and no medically based restrictions are indicated.15 See Appendix A for further discussion.
Contrast sensitivity is a measurement of both the quantity and quality of vision. It is a strong predictor of driving performance. It is rarely abnormal in persons who have healthy eyes and is not indicated as a routine screening test for LEOs. If measured, the LEO should have Pelli Robson score ≥1.5 in the worse eye. Those with a score of 1.25 or less are unlikely to be able to perform the essential job functions of a LEO. Those with scores between those values should have annual monitoring. See Appendix A for further discussion.16