A Guide for Opticians
and Consumers
Part I

                        

                        

Abbreviations, Definitions, and Terms

AMBLYOPIA, LAZY EYE, affects just two to three percent of the population. But, if left uncorrected, this vision problem can have a very big impact on those affected. Central vision fails to develop properly, usually in one eye, which is called amblyopic. A related condition, strabismus, sometimes causes amblyopia.

Untreated amblyopia may lead to functional blindness in the affected eye. Although the amblyopic eye has the capability to see, the brain "turns off" this eye because vision is very blurred, and the brain elects to see only with the stronger eye.

    
Clearer vision occurs in the eye with normal sight
Blurry vision occurs in the lazy eye, even with glasses

Signs and Symptoms

Amblyopia generally develops in young children, before age six, and symptoms often are noted by parents, caregivers or health-care professionals. These symptoms include:

Eyestrain
Overall poor visual acuity
Squinting or completely closing one eye to see
Headaches

Causes

Trauma to the eye at any age can cause amblyopia, as well as a strong uncorrected refractive error (nearsightedness or farsightedness) or strabismus. It's important to correct amblyopia as early as possible, before the brain learns to entirely ignore vision in the affected eye.

Treatment

Amblyopic children can be treated with vision therapy (which often includes patching one eye), atropine eye drops, the correct prescription for nearsightedness or farsightedness, or surgery.

Vision therapy exercises the eyes and helps both eyes work as a team. Vision therapy for someone with amblyopia forces the brain to see through the amblyopic eye, thus restoring vision.

Sometimes the eye doctor or vision therapist will place a patch over the stronger eye to force the weaker eye to learn to see. Patching may be required for several hours each day or even all day long and may continue for weeks or months. If you have a lot of trouble with your child taking the patch off, you might consider a prosthetic contact lens that is specially designed to block vision in one eye but is colored to closely match the other eye.

In some children, atropine eye drops have been used to treat amblyopia instead of an eye patch. One drop is placed in your child's good eye each day (your eye doctor will instruct you). Atropine blurs vision in the good eye, which forces your child to use the eye with amblyopia more, to strengthen it. One advantage is that it doesn't require your constant vigilance to make sure your child wears the patch.

Recently a study compared atropine therapy with patching in 419 children age 3 to almost 7 and found it an effective alternative. As a result, some previously skeptical eye care practitioners are using atropine as their first choice over patching.

Anissa's Fun Patches

Innovative amblyopia patches help children comply with their amblyopia treatment.
You can help your child accept patching more readily. Anissa's Fun Patches, for instance, require no adhesive because they slide onto the temple of an eyeglass frame.

However, atropine does have side effects that should be considered: light sensitivity (because the eye is constantly dilated), flushing and possible paralysis of the ciliary muscle after long-term atropine use, which could affect the eye's accommodation, or ability to change focus.

If your child has become amblyopic due to a strong uncorrected refractive error or a large difference between the refractive errors of both eyes, amblyopia can be treated with eyeglasses or contact lenses in the correct prescription. Your eye care practitioner may prescribe an eye patch along with the new glasses or contact lenses.

Surgery is best for amblyopic children with an underlying physical problem, such as strabismus. The surgery corrects the muscle problem that causes strabismus so the eyes can focus together and see properly.

ASTIGMATISM is a blurred vision condition produced by a football-shaped cornea, which is too steep in one meridian and too flat in another. An astigmatic cornea focuses light in two different places in the eye, adversely affecting both near and distance vision. See CYLINDER below.

Astigmatism
Objects appear blurry at all distances

     
      BEFORE Corrected Vision                     AFTER Corrected Vision          

AXIS corresponds to the orientation of the cylinder power in terms of degrees from 0 to180.

BRIDGE is that part of the frame front that connects the eyewires and holds the frame in place at the nose.

BRIDGE TYPES: KEYHOLE BRIDGE is a type of bridge that fits only on the sides, and does not touch the top. Resembles a keyhole. SADDLE BRIDGE is a type of bridge that sits uniformly over the nasal crest.

CATARACT is a clouding of the lens of the eye. More in depth cataract data, here.

Experience simulated eye diseases here. Cataract simulator. Detached retina simulator. Diabetic retinopathy simulator. Glaucoma simulator. Macular degeneration simulator.

CYLINDER corresponds to numbers indicating the amount of astigmatism correction. See ASTIGMATISM above.

              

Left image, spherical lens with no cylinder.
Vertical and horizontal meridians are equal.
Right, lens with cylinder to correct astigmatism.
Vertical and horizontal meridians are unequal.

DBL is the Distance Between Lenses, the least distance between the two lenses, or the frame's bridge size.

DIOPTER is a measurement of lens refractive power equal to the reciprocal of the focal length of a lens in terms of meters, e.g., a 2.00 Diopter lens will bring parallel rays of light to a focus at a half meter, i.e., .50 meters. Also, the measurement of the degree to which light converges (a plus Diopter, +2.00D, lens will correct farsighted vision), or the degree to which light diverges (a minus Diopter, -2.00D, lens will correct nearsighted vision).

"It is how well the eyewear makes contact with the
Patient that ultimately defines Ophthalmic Dispensing."

DISPENSING OPTICIAN, or LICENSED DISPENSING OPTICIAN, LDO, is herein defined as a Board Certified and-or State Licensed healthcare provider who specializes in the design of prescription eyewear, i.e., lenses, frames and contact lenses, which includes the duplicating, measuring, inspecting, and verifying of prescription lenses, and any subsequent frame Alignment or other Adjustments, including the Final Fitting, whereby the Patient's visual comfort, and the long-term comfort and wear-ability of their eyewear is the primary objective.

An expanded definition as defined by the U.S. Dept. of Labor, Bureau of Labor Statistics: "Designs, measures, fits, and adapts lenses and frames according to written optical prescription or specifications; assists with selecting frames; measures for size of eyeglasses and coordinates frames with facial and eye measurements and optical prescriptions; prepares work order for optical laboratory containing instructions for grinding and mounting lenses in frames; verifies exactness of finished lens spectacles; adjusts frame and lens position to fit; shapes or reshapes frames. Includes contact lens Opticians." See OpticiansForChange.com.

"When's the last time you saw or heard a retail optical
ad that promoted the custom fitting of eyewear?"

DISTOMETER is for measuring Vertex Distance. When an eyeglass prescription reaches a certain strength, the vertex distance between the eyes and the Patient's eyeglasses must match the vertex distance between the Patient's eyes and the Phoropter, i.e., the instrument used during the comprehensive eye examination to determine refractive error, at the time of the Doctor's refraction. Patients can experience problems with an Rx of about 6 Diopters of power, give or take. A 1mm difference between the working distance of the Phoropter at the time of their exam and the fitting distance of their corrective lenses can cause significant refractive error relative to the Patient. Therefore it is important to match the vertex distance between that of the Phoropter and their glasses, or modify the optics in order to accommodate the actual fitting distance of the eyeglasses. The Distometer is an instrument used for measuring and calculating this compensation.

The Distometer measures the vertex distance and compensates for the average eyelid thickness. The Patient closes their eyes in a relaxed fashion with the eyeglasses in position while the Optician places the flat end on the Patient’s eyelid directly behind the lens. As the elongated button at bottom of photo above is pushed the Distometer arm moves from its resting position. As it lightly touches the back of the lens, the Optician observes the reading. The rotating chart above is designed to calculate the correct Rx compensation. From here, the Optician can adjust the frame and fit the glasses at that same distance or determine the necessary changes to be made in the Rx. Note: The further away the lenses are positioned from the cornea, the smaller the field of view.

EYE DISEASES - CATARACTS, DIABETES, GLAUCOMA

Cataracts: The natural lens in the eye gradually becomes less clear as we get older. When opacities develop in the lens and the lens gets too hazy, vision will be impaired. When the cataract affects the vision to the extent that one cannot read or see distant objects comfortably, cataract surgery may be required.

Diabetes: Diabetic Patients should have a dilated retinal examination each year. Laser treatments have proven to slow the progression of retinal eye disease for many Patients. Diabetes often stimulates the growth of new blood vessels in the back of the eye, which ultimately leak and damage the retina. If this condition is discovered early, laser treatment can destroy these vessels.

Glaucoma: Glaucoma gradually destroys the optic nerve tissue in the back of the eye. The greatest danger of glaucoma stems from the fact that the disease is painless and without obvious symptoms until significant damage has occurred. The most common cause is from pressure being too high inside the eye, but vascular disease and other diseases can also cause glaucoma. A full eye exam includes checking the pressure of the eye, screening for peripheral vision defects and analyzing the appearance of the optic nerve. If you are diagnosed with glaucoma, your eye care professional may prescribe medications that lower the eye pressure. Most forms of glaucoma are successfully treated with eye drops. Laser treatments and eye surgery are secondary treatments that offer alternative ways to treat more advanced glaucoma.

EYEWEAR, as defined within the Ophthalmic Industry, is inclusive of spectacles and contact lenses. But for the purposes of our Frame Fitting Course, EYEWEAR refers to any sunwear, streetwear, safety, athletic, or other occupational or avocational, corrective or plano lenses, worn in combination with an ophthalmic frame.

EYEWIRE is that portion of the frame front into which the lenses are inserted or mounted and which is connected to its opposite by the bridge.

FRAME is that portion of a pair of eyeglasses that is designed to hold the lenses in the proper position before the eyes.

                

HANDS-ON DISPENSING AND DELIVERY is herein defined as those procedures, which involve eyewear adjustments performed by a skilled Dispensing Optician, which specifically include, a) the visual and 'touch and feel,' hands-on-the-Patient, tactile assessment of the frame, while it is in-place, on-the-face of the Patient, in order to determine any misalignment, and b) any subsequent multi-dimensional hands-on-the-Patient, tactile, 'touch and feel' handcrafting that is required to refit, align, adjust, reshape, bend, stretch, twist and sculpt the components of the frame in order to personalize the eyewear for maximum visual comfort and wear-ability. See example.

Special Note: This level of craftsmanship can be accomplished only after a visual as well as a tactile, i.e., touch and feel, assessment of the frame, in-place, on the Patient, and requires the removal and re-placement of the eyewear directly on the Patient, BY THE OPTICIAN, as many times as necessary to complete the procedure. (Unfortunately, many of today's Dispensers make no contact with either the Patient or their eyewear while in place, on-the-face, whereby it is impossible to make a significant assessment or subsequent multi-dimensional adjustments to the frame. This practice is akin to a Dentist making no direct contact with a Patient while attempting fit dentures. Sadly, latter generation Dispensers give little or no attention to fitting a new frame after it arrives from the lab, presumably four-point inspected on a flat surface by the lab technicians. Just as in the case of fitting a set of dentures, a frame must ultimately be custom fitted to the variable dimensions of the Patient, not the one-dimensional surface of a flat table. The lab only zeroes-out any frame misalignment in lieu of anticipated adjustments by the Optician.)

Furthermore, a properly executed hands-on, in-place, on-the-face assessment, and frame fitting procedure requires not only appropriate communications between the Dispenser and the Patient, but some direct physical contact must occur as well. A proper hands-on fitting involves the repeated removal and re-placement of the frame on and off the Patient by the Dispenser until such time as the fitting is completed, which depends of course on the experience of the Dispenser, any asymmetric features of the Patient, and the type and design of the eyewear. See example. The Dispenser cannot rush the procedure. Much time is actually saved in the long run when the fitting is done with sensitivity and patience whereby Patient return visits are minimized.

HEALER is one who contributes to making a person whole.

HEALING ARTS are those skillful practices, which contribute to the health and wellness of those to whom they are applied. See Ophthalmic Health and Wellness.

HEALTHCARE PROVIDER is any professional individual or organization, which provides health and wellness products and services to the public. Note: The Florida Board of Opticianry is an entity within the Florida Department of Health, which has jurisdiction over Florida Healthcare Providers.

HYPEROPIA is another word for FARSIGHTEDNESS, which is a common vision problem, affecting about a fourth of the population. People with hyperopia can see distant objects very well, but have difficulty focusing on objects that are up close. Farsightedness can be corrected with glasses or contact lenses to change the way light rays bend into the eyes. If your glasses or contact lens prescription begins with plus numbers, like +2.50, you are farsighted. You may need to wear your glasses or contacts all the time or only when reading, working on a computer or doing other close-up work.

Hyperopia or Farsightedness
Near objects appear blurry, far objects clear

     
          BEFORE Corrected Vision                     AFTER Corrected Vision 

LASIK SURGERY or LASER VISION CORRECTION occurs when a flap is surgically cut in the cornea and gently folded back. An Excimer Laser is used to reshape the cornea into a flatter shape (this is reminiscent of a contact lens that corrects vision by forming a new shape on the cornea). The flap is then put back in place, acting like a natural bandage. The healing process is quick and the discomfort level is quite low.

Following the procedure Patients will often say that they did not feel anything, and could see well the very first day. Most people have improved vision in 24-48 hours but it must be noted that each person will heal at a different rate. Vision, although greatly improved immediately after surgery, often continues to improve for some weeks, even months.

LASIK is not for everyone. People's eyes are different and it may not be the best course of treatment for you. Consult your eye care professional. 

MYOPIA is another word for NEARSIGHTEDNESS, which is a vision problem experienced by up to about one-third of the population. Nearsighted people have difficulty reading highway signs and seeing other objects at a distance, but can see for up-close tasks such as reading or sewing. Nearsighted people often have headaches or eye strain and might squint or feel fatigued when driving or playing sports. If you experience these symptoms while wearing your glasses or contact lenses, a comprehensive eye exam as well as a new prescription may be needed. Myopia occurs when the eyeball is slightly longer than usual from front to back. This causes light rays to focus at a point in front of the retina, rather than directly on its surface. Nearsightedness runs in families and usually appears in childhood. This vision problem may stabilize at a certain point, although sometimes it worsens with age. This is known as myopic creep. Nearsightedness may be corrected with glasses, contact lenses or eye surgery.

Myopia or Nearsightedness
Distant objects appear blurry, near objects clear

     
      BEFORE Corrected Vision                     AFTER Corrected Vision          

OPHTHALMIC means anything that pertains to the eye or is situated near the eye.

OPHTHALMIC DISPENSER is any healthcare provider who specializes in the design of prescription eyewear, i.e., lenses, frames and contact lenses, which includes the duplicating, measuring, inspecting, and verifying of lenses, and any subsequent Alignment and other Adjustments, including the Final Fitting of the eyewear. See DISPENSING OPTICIAN, LDO.

"It is how well the eyewear makes contact with the
Patient that ultimately defines Ophthalmic Dispensing."

OPHTHALMIC DISPENSING is herein defined as those frame adjustments performed by a qualified Dispensing Optician, which include, a) the fullest discovery and maximum consideration of the Patient's visual needs, b) the assistance and advice to the Patient regarding the appropriate choice of lens design and frame selection, c) the duplicating, measuring, inspecting, and verifying of lenses, and d) any subsequent Gross Frame Alignment and Subtle Frame Adjustments, including the Final Fitting.

OPHTHALMIC HEALTH AND WELLNESS is herein defined as that state of well-being wherein a Patient's visual health and comfort is supported, and the long-term wear-ability of their eyewear is provided and maintained.

OPHTHALMIC PATIENT is herein defined as one who needs or receives health related services having to do with their vision and-or eyewear.

The Three O's of Eye Care
Ophthalmologists, Opticians and Optometrists

OPTHALMOLOGIST, MD or DO, is a State Licensed-Board Certified healthcare provider who specializes in the diagnostic, surgical, and other medical treatments as well as the refraction of the eye in order to determine any refractive visual error and the means by which the error can be corrected. An Ophthalmologist is a Physician, Doctor of Medicine or Doctor of Osteopathy, who specializes in the comprehensive care of the eyes and visual system in the prevention of eye disease and injury. An Ophthalmologist must complete four or more years of college level premedical education, four or more years of medical school, one year of internship, and three or more years of specialized medical and surgical training and experience in eye care. An Ophthalmologists is a Physician who is qualified by lengthy medical education, training and experience to diagnose, treat and manage all eye and visual system problems, and is licensed by a state regulatory board to practice medicine and surgery. The Ophthalmologist is a medically trained specialist who can deliver total eye care: primary, secondary and tertiary care services, i.e., vision services, contact lenses, eye examinations, medical eye care and surgical eye care, and diagnose general diseases of the body.

OPTICIAN, LICENSED DISPENSING OPTICIAN, LDO, see also DISPENSING OPTICIAN. An Optician is a healthcare provider who is qualified to fit, adapt, and dispense eyeglasses or contact lenses and other optical devices from the written prescription of a licensed Physician or Optometrist, or to duplicate same. An Optician's education consists of (2) two years at an accredited college of ophthalmic dispensing. Additionally required for Florida state licensure is national certification by the American Board of Opticianry and National Contact Lens Examiners. Then, to achieve state licensing, an Optician must pass a State Board examination. To maintain licensure, an Optician must fulfill continuing education requirements. (Note: An Optician is as related to the ophthalmic industry just as a Pharmacist is related to the pharmaceutical industry. Both fill the prescription needs of Patients.)

OPTOMETRIST, OD, is a State Licensed-Board Certified healthcare provider who specializes in the refraction of the eye in order to determine any refractive visual error and the means by which the error can be corrected. The Optometrist is a health care professional trained and state licensed to provide primary eye care services. These services include comprehensive eye health and vision examinations; diagnosis and treatment of eye diseases and vision disorders; the detection of general health problems; the prescribing of glasses, contact lenses, low vision rehabilitation, vision therapy and medications; the performing of certain surgical procedures; and the counseling of Patients regarding their surgical alternatives and vision needs as related to their occupations, avocations and lifestyle. The Optometrist will have completed pre-professional undergraduate education in a college or university, and four years of professional education at a College of Optometry, leading to a Doctor of Optometry, OD, degree. Some Optometrists complete a residency.

Phoropter

PHOROPTER is the instrument that contains multiple lenses for use by a refractionist, i.e., Optometrist, OD, or Ophthalmologist, MD, during a comprehensive eye examination to determine any refractive error. Any prescription for eyeglasses or contact lenses is determined mostly with this instrument.

PRESBYOPIA is a term used to describe a condition whereby a person needs vision assistance by way of READING GLASSES and-or BIFOCALS or TRIFOCALS. During middle age, usually beginning in the 40s, people experience blurred vision at near points, such as when reading, sewing or working at the computer. There's no getting around it -- this happens to everyone at some point in life, even those who have never had a vision problem before. Currently an estimated 90 million people in the United States either have presbyopia or will develop it by 2014. This is generating a huge demand for eyewear, contact lenses, and surgery that can help presbyopes deal with their failing near vision.

Presbyopia
Objects appear blurry at near and intermediate distances

     
      BEFORE Corrected Vision                     AFTER Corrected Vision          

When people develop presbyopia, they find they need to hold books, magazines, newspapers, menus and other reading materials at arm's length in order to focus properly. When they perform near work, such as embroidery or handwriting, they may have headaches or eyestrain or feel fatigued. Presbyopia is caused by an age-related process. This is different from astigmatism, nearsightedness and farsightedness, which are related to the shape of the eyeball and caused by genetic factors, disease or trauma. Presbyopia is generally believed to stem from a gradual loss of flexibility in the natural lens inside your eye.

These age-related changes occur within the proteins in the lens, making the lens harder and less elastic with the years. Age-related changes also take place in the muscle fibers surrounding the lens. With less elasticity, the eye has a harder time focusing up close. Other, less popular theories exist as well.

PRISM is an element added to the prescription if the Patient's eyes need help working more effectively together, and-or to remain in proper alignment.

RX is an abbreviation of the word, PRESCRIPTION, and refers to the document, which expresses the lens powers and other pertinent details, and is signed by the attending Refractionist, i.e., Optometrist, OD, or Ophthalmologist, MD.

SPRING HINGE is a type of hinge on eyeglass frames that flexes, making the frames more durable. Spring hinges also help keep the eyewear in proper alignment and help reduce the need for some adjustments.

TEMPLES can be generally defined as the hinged extensions on each side of the frame front, which when the frame is worn, extend along each side of the head, and in most styles, bend down behind the ears. Temples are made to be reshaped to follow the contours of the skull (see example) and avoid direct contact with ears, while resting evenly against the skull with minimum pressure, whereby they act to hold the eyewear comfortably in place. See Variations on Styles of Temples.

TEMPLE-END is that part of the temple that extends down behind the ear and makes direct contact with the mastoid portion of the skull. The temple-end is designed to be reshaped to follow the contours of the skull whereby it acts to stabilize and hold the eyewear in place for long-term comfort and wear-ability. The temple-ends, with all gaps and space removed, and making full contact with the skull, NOT THE EARS, are the primary means of holding the eyewear in place.

VERTEX DISTANCE is the distance between the back surface of a corrective lens, i.e. glasses (spectacles) or contact lenses, and the front of the cornea. Increasing or decreasing the vertex distance changes the optical properties of the system, by moving the focal point forward or backward, effectively changing the power of the lens relative to the eye. Since most refractions are performed at a vertex distance of 14mm, the power of a corrective device fitted at a different vertex distance may need to be compensated to effect the same correction of the Doctor's initial refraction. Usually, when the lens power exceeds ±6.00 or ±7.00 diopters, depending on the Patient, vertex distance must be considered as an important factor. See Distometer. Note: A Refraction is that portion of a comprehensive eye exam that is performed using a Phoropter.

WRAP-AROUND EYEWEAR (WRAP): Type of eyeglass lens-frame that curves around the head, from the front to the side. Wrap-around sunglasses tend to offer extra sun protection because the lenses usually hug close to the face and protect the delicate tissue around the eye as well. Get the rap on wrap-arounds here. See Advisory on Frame Selection here.