From the office to the military: addressing occupational visual needs

Contact Lenses and Eyewear

Deciding how to best address a patient’s occupational visual needs may be quite simple or complex. In fact, depending on the career the patient is pursuing, the decision may already be made for the practitioner. Certain work environments are flexible in the type of corrective eye wear that a patient may use, whereas others may impose restrictions such as prohibiting refractive surgery as a vision correction option.

Office evaluation

While most people working in an office environment have their choice of vision correction options, the associated environmental conditions such as lighting, heating and monitor placement can all have adverse effects on a person. Some companies address their employees’ complaints about the office environment by bringing in an outside source to help determine and ultimately resolve the problem. James E. Sheedy, OD, PhD, FAAO, an associate professor at the Ohio State University College of Optometry and founder of the Computer Eye Clinic, visits companies who report that their employees are experiencing visual difficulties and discomfort in the work environment.

“Sometimes, the problems are caused by elements in the work environment, and sometimes they are vision problems that need correction,” Dr. Sheedy told Primary Care Optometry News. “So, to solve all the vision problems that people have in the workplace, you really need to evaluate both the vision environment aspects as well as the individual vision problems they may have.”

In workplaces where his services are requested, he said, there may be a small group of employees who have complaints about the environment, or even a workers’ compensation suit, and the employer may need help to resolve it. First, Dr. Sheedy said, he sends out questionnaires so the employees may express specifically what types of problems they are experiencing, such as eye strain, headaches, neck aches and eye dryness and irritation.

“Then, I will go through the workplace, department by department,” he said. “Say it’s a fairly large room with maybe 25 employees in there, in both cubicles and offices. I will evaluate the lighting from the windows, overhead lights and the illumination levels experienced at the desk surfaces. I will find out what types of computer displays they’re looking at, and I will determine if there are any particular shortcomings of the displays themselves. I’ll look for reflection problems and display placement.”

After this short assessment of the area, Dr. Sheedy then arranges to meet each individual who indicated that he or she has a problem, and he evaluates all aspects of that particular area. Some changes, he said, are as simple as tilting someone’s computer up or down or reorienting it slightly so that the reflection of a window no longer causes a glare.

“I also bring along some simple screening tools so that I can screen visual acuity, binocularity and accommodation,” he said. “And I evaluate the glasses that he or she is using to see if they’re appropriate for the job,” he said. “Very often, computer users are using bifocals or progressive-addition lenses, which are not well-designed for the computer workstation and cause people to get into an awkward posture.”

Lighting, presbyopia common problems

Dr. Sheedy said that one of the most common problems he encounters when evaluating a person’s work environment is lighting. “Bright light in peripheral vision causes discomfort,” he said. “This is particularly a problem for computer users. If people are looking down at their desks, those bright lights are not very prevalent in their field of view. But when people are looking horizontally in a room, bright overhead lights are in the field of view and cause discomfort. By the end of the day, that significantly contributes to eye fatigue and eyestrain. That is the most significant environmental factor I see.”

As far as eye-related conditions go, Dr. Sheedy said that presbyopia causes the most problems. “Your typical bifocals and progressive-addition lenses intended for everyday wear are designed to allow people to see clearly at about 16 inches and with a downward gaze angle of about 25°,” he said. “That’s where people hold a book, but that’s not where the computer screen is. It’s only down about 5° to 10°, and it’s farther away — about 24 inches. So a bifocal wearer, in order to see the computer screen, would need to tilt his or her head back and move closer to the computer screen to really see it clearly. Now they’re in an awkward posture, so they get neck aches and backaches. Or, they can sit comfortably, and the screen is blurry.”

Dry eyes, of course, can also be a side effect of computer use because the blink rate decreases. In addition, dry air and low humidity often circulates in office environments, Dr. Sheedy added.

Contact lenses in the workplace

When it comes to wearing contact lenses at work, the type of work a patient does figures predominantly into whether or not it is appropriate. However, patients can wear contact lenses in most work environments, even those in the industrial arena, said Anthony P. Cullen, OD, PhD, professor of optometry, biology and engineering at the University of Waterloo School of Optometry, and author of Contact Lenses in the Work Environment. “There are very few environments in which you cannot wear contact lenses; that’s the bottom line,” he said. “A lot of perceived hazards are not real.”

Soft contact lenses are much more protective in many environments than rigid gas-permeable (RGP) lenses, even in industrial surroundings, said Dr. Cullen, mainly due to the diameter of RGPs. “RGPs do not cover the whole cornea, so, mechanically, things can get underneath much easier,” he said.

While soft lenses are not intended to be eye protectors, they can be worn in a wider variety of work situations. “In some environments that are dusty or have fumes or chemicals in the air, soft lenses can be worn quite safely and comfortably,” he said. “Daily disposables lend themselves to this sort of regimen. Because if any of the contaminants become attached to the lens, they are discarded with the lens.

“Of course, if you’re working in an industry where protective eye wear is mandated, then obviously you must wear it,” he added. “Conversely, your contact lens does not negate the effect of the protective eye wear. So if you’re wearing protective eye wear and you’ve got a contact lens underneath, you’re at no more risk than the person who is wearing protective eye wear without contact lenses.”

Risks with contact lens wear

Certain unique work environments can present risks with contact lens wear, said Dr. Cullen, such as those where there are extremes of heat, particularly radiant heat. “Furnace environments and some glass-blowing environments will dry out soft contact lenses and cause them to stick to the eye,” he said. “But that is not a big problem because you either let it rehydrate on its own from natural tears or you put in an artificial tear and wait for the lens to hydrate. The danger comes when someone tries to force a lens out when it’s still adherent to the eye.”

Refractive surgery in the military

Contact lenses may be safe and permitted in most work environments, but what about refractive surgery? New recruits about to join the Navy, Marines, Army, Air Force and Coast Guard need to be aware of each branch’s particular guidelines as far as what type of refractive surgery, if any, is allowed.

According to Steve Schallhorn, MD, director of cornea and refractive surgery at the Naval Medical Center in San Diego as well as a captain in the Navy, any new recruits seeking refractive surgery are required to get a waiver. “Any form of refractive surgery is disqualifying for entry into the service,” he said. “However, a uniform set of waiver requirements has been established to allow entrance into the service for those who have had refractive surgery. That is the mechanism by which the Department of Defense can specify the requirements.”

Navy/Marine Corps requirements

Photorefractive keratectomy (PRK) can be waived in all branches of the military, said Dr. Schallhorn. Beyond that, the requirements for each branch and the specific occupations within those branches vary slightly.

Because the Navy provides medical care for the Marine Corps, the two share requirements for a waiver. For new accessions, excluding Special Forces and aviation, both PRK and LASIK are waiverable, provided the patient had less than or equal to 8 D of preop ametropia and it is at least 3 months postop. Radial keratotomy (RK) is not permitted, and Intacs prescription inserts (Addition Technology, Fremont, Calif.) are permitted on a case-by-case basis. Refractive stability must be 0.5 D or less change in both sphere and cylinder over 1 month, with an end result of 20/20 best-corrected visual acuity. There must be no visual symptoms related to surgery, and the patient must be able to provide preop and perioperative reports and meet all other applicable vision standards.

For new accessions in special forces, such as Navy SEALs, only PRK is acceptable. LASIK is considered only if it is at least 6 months postop, the patient is able to provide preop and perioperative reports, and the patient is accepted into study to provide long-term follow-up. All of the other requirements are the same.

For new aviation candidates, the requirements are much more stringent. Only PRK is allowed — LASIK is disqualifying, with no exceptions. Pre-PRK refractive error must be ± 5.50 D (total) or less in any meridian with ±3 D or less of cylinder and 3.50 D or less of anisometropia. The patient must meet all other aviation entrance requirements and be accepted into flight training, and he or she must be accepted into study to provide long-term follow-up. All of the other requirements are the same.

There are too many unanswered questions regarding LASIK at this time for it to be authorized for aviation candidates, said Dr. Schallhorn. “Aviators are an incredibly important and expensive-to-train national asset,” he said. “It’s not a matter of bowing to public pressure or demand to allow these surgeries to be done on them. It’s a matter of making careful, cautious decisions on what is best for that community.

“What’s the difference between PRK and LASIK? The flap that is created,” he continued. “There are issues relating to that flap. For instance, could ejecting from an aircraft displace the flap? No one has been able to answer that or the issues relating to it: Will refraction or acuity change with a change in pressure or a change in oxygen content? How well can somebody with LASIK see through night-vision goggles? Studies need to bear that out.”

LASIK for aviators has not been dismissed completely, however. “Thoughtful, carefully done” studies are being conducted, and these issues have been under scrutiny for about 4 years now, Dr. Schallhorn said. “Those are many of the aspects we’ve been looking at; we looked at them with PRK, and we’re in the process of looking at them with LASIK now,” he said. “We’ve been doing studies on divers — we’ve enrolled lots of individuals in LASIK studies to look at quality of vision and related issues. We have a study program where we are allowing folks who have had LASIK and a good outcome to go into SEAL training.”

Army, Air Force, Coast Guard

For Army new accessions, PRK and LASIK are both waiverable, with no LASIK being permitted in aviation or special forces candidates, no RK and Intacs on a case-by-case basis. The Army requires at least 3 months postop, with all other requirements the same as the Navy/Marines. For new accessions in special forces, LASIK is waiverable, with all other requirements the same.

For Coast Guard new accessions, PRK is waiverable, with no surgery in aviation candidates and no RK, LASIK or Intacs. It requires at least 12 months postop, with refractive stability (0.5 D or less change over 3 months) and no loss of preop best-corrected visual acuity. All other requirements are the same.

PRK and LASIK are both waiverable for Air Force new accessions, with no RK or Intacs and no LASIK in aviation or Special Forces candidates. The Air Force also requires patients to be at least 12 months postop and have refractive stability (0.5 D or less change in 3 months) and no loss of preop best-corrected visual acuity. Air Force new accessions and aviation and Special Forces candidates may have undergone PRK only; LASIK is disqualifying. Candidates must meet all other aviation entrance requirements, be accepted into flight training and be enrolled in a surveillance program for long-term assessment. All other requirements are the same as Air Force new accessions.

The stipulation that recruits not have more than –8 D uncorrected vision is not just for those considering refractive surgery, Dr. Schallhorn said. “That’s a requirement for general enlistment,” he said. “Someone who is extremely nearsighted or farsighted can have other ocular abnormalities, such as a higher incidence of retinal detachment or myopic degeneration of the macula. The military does not want to accept people who they know have a much higher chance of having problems. But they do consider waivers for different types of positions and depending on the job requirements.”

Ortho-K not allowed

One form of vision correction that is not allowed in the military is orthokeratology (ortho-K), said Dr. Schallhorn, because of the instability of visual acuity. “You can do ortho-K, and it may work, but 3 days later, if you can’t wear the retainers, uncorrected vision is going to gradually revert to what it was prior to treatment,” he said. “It’s not stable unless you can maintain that wear pattern with the contact lenses. The military screens for it pretty carefully for aviation entrance; they make sure that recruits don’t have retainers with them, and if they suspect it, they measure them every day. They’re pretty concerned about it. That rule probably will not change.”

Police, firefighters: rules vary

On a more local level, law enforcement officers and firefighters must follow the guidelines established by the city or state. Because these occupations often find their employees in dangerous situations demanding excellent vision, certain restrictions are placed on refractive surgery that differ all over the country.

“If law enforcement officers get into a situation, such as a fight, they’re worried about getting their glasses knocked off,” said Colman Kraff, MD, a private practitioner in Chicago. “Those are some of the reasons they want to have this procedure done.”

Dr. Kraff said that he has treated patients who are attempting to become secret agents in the FBI, police officers, firefighters and professional athletes. One or two patients a week who inquire about having LASIK are law enforcement officers or firefighters, he noted. And while he has performed both PRK and LASIK on them, the majority of patients — about 95% — have LASIK done.

“In every police department, it’s a little bit different,” he said. “Each state and each city have different guidelines. Most don’t have a problem with their employees having refractive surgery.”

As an example, the Web site for the Los Angeles Police Department states that the department requires a 6-month deferral period after LASIK has been performed. The Las Vegas Metropolitan Police Department necessitates a 1-year post-surgery waiting period. In New York, a state police trooper “will not be permitted to participate in subsequent phases of the selection process until at least 30 days after successful completion of the surgery.”

For Your Information:

• James E. Sheedy, OD, PhD, FAAO, is an associate professor at Ohio State University, College of Optometry. He may be reached at 320 West 10th Ave., Columbus, OH 43210; (614) 247-7632; fax: (614) 688-5603.
• Anthony P. Cullen, OD, PhD, is professor of optometry, biology and systems design engineering at the University of Waterloo School of Optometry, Waterloo, Ontario, Canada N2L 3G1; (519) 888-4567, ext. 3680; fax: (519) 725-0784; e-mail: acullen@uva.uwaterloo.ca.
• Steve Schallhorn, MD, is director of cornea and refractive surgery at the Naval Medical Center in San Diego as well as a captain in the Navy. He may be reached at 34800 Bob Wilson Dr., San Diego, CA 92134; (619) 532-6702; fax: (619) 532-7272; e-mail: scschallhorn@nmcsd.med.navy.mil.
• Colman Kraff, MD, is in private practice in Chicago. He may be reached at Ste. 606, 25 E. Washington, Chicago, IL 60602; (312) 444-1111; fax: (312) 444-1953; e-mail: ckraff@ix.netcom.com.