An age old question that many patients, and others have, is what is the difference between an Optometrist and an Ophthalmologist?

The true answer is somewhat complicated. Interestingly, based on my experience as an Optometric Physician, Lawyer and Educator, most Optometrists and Ophthalmologists do not know the complete answer.

The functional and legal roles and differences between these two types of Eye Doctors as is with all licensed professions, controlled by State Law and Statutes within the United States. Also, in other countries the legal differences and nomenclature used to describe these two professions may be significantly different than the United States. For example in recent decades within the United States many Optometrists and State Laws refer to Optometrists as ‘Optometric Physicians’

As an Optometrist (Optometric Physician), former professor, lawyer, and State Legislative Lobbyist I have had an intimate look at the true answer.

Because both Professions practice under different types of Statutory Licenses outlined by State Law, the only Doctor actually practicing as an Eye Doctor under Statute or Law is The Optometrist. Optometrists are specifically licensed and controlled by Statute to practice as an Eye Doctor or Eye Physician. By Statute Ophthalmologists are Licensed only as General Medical Doctors, obtained at the time they finish their general medical training, and are not specifically licensed to practice as an Eye Doctor by the State Government. They become Eye Doctors through Specialty Training in a residency program after they receive their general medical degree which may be an M.D., D.O., or MBBS or other designation based on their country of Training.

In fact, no Specialty in Medicine is licensed by Statute and Law to actually practice their Specialty. It is expected that they should pass a Board Certification Exam after a qualified residency in order to practice the specialty. This in fact has been the age old problem with specialties in Medicine, the quality of residency training, certification and lack of State and Government licensing of Medical Specialists has over history presented problems for securing the safety of patients seeking medical care because the public generally has no idea as the actual training, qualifications and certifications of medical specialists, particularly due to the wide variance of these factors and the lack of government and State licensure. The general government license that Medical Specialists obtain before they even enter into specialty training cannot therefore adequately govern Specialty practice.

This is just the opposite with Doctors of Optometry (Optometrists) whose training and practice is specifically dictated and outlined by State Statutes and Law. For example all Optometry School in the United states follow a strict, detailed and uniform course dictated by Statutory Law in every State ensuring that patients seeking care by Optometric Physicians (Optometrists) receive a uniform and specific standard of care. For example, if a patient is treated for the disease/disorder of Glaucoma by an Optometrist, the State Law and Statute details the equipment, process and procedures that must be used. This is not so for treatment by an Ophthalmologist who is governed only by a General Medical License received even before any Ophthalmology Training.

Medical Specialists become specialist only after their specialty training and many do not even sit or pass the specific privately required Board Certification Examinations which are generally used to allow them to obtain privileges to practice in Institutions and Hospitals.

Generally in modern times Ophthalmologists within the United States are mostly Eye Surgeons who specialize in Cataract, Retina, Cornea and other surgical disciplines. Optometrists generally practice as Primary Care Eye Doctors specializing in diagnosing & Treating Vision Anomalies, Eye Disease, and other Non Surgical Eye Treatments. However, Optometrists by law in many States may also engage in various Eye Surgery Treatments.

Interestingly, the public generally may not understand that in the case of Eye Doctors, the reference to Ophthalmologists as the Eye Specialist really references the fact that they specialize in Eye Care rather and practice as a General Medical Doctor as their license allows them to. Optometrists are also Eye and Vision Specialists in Special Areas of Training and Practice which they obtain in residencies and other Post-Graduate Training after obtaining their Doctor of Optometry Degree (O.D.).

Also, due to the legislative requirements for Optometric Education most Schools and Colleges of Optometry require the same or more training in General Medicine and Pharmacology to obtain the Doctor of Optometry Degree (O.D.) as required for the Doctor of Medicine (M.D.) Degree, and  usually in Courses taught by the same professors.

Another interesting fact about these two professions is that despite their differences in Training and licensure, their scope of practice is essentially the same as relates to the standards of care and treatment, and represents a unique situation in Health Care delivery and practice. Optometry is essentially the only none Allopathic (M.D.), or Osteopathic (D.O.) type of proprietary Health Practitioner that practices what is essentially a Medical Specialty outside of Allopathic or Osteopathic Medicine.

The functional Difference between an Optometrist and a properly trained and certified Ophthalmologist is therefore very similar to the difference between a Cardiologist and Cardiac Surgeon, or a Neurologist and Neuro Surgeon.

Having considered the facts relating to these two professions, patients can ask the appropriate questions about their particular Eye Doctor’s training and other qualifications, and then make an informed decision as to which type of Eye Doctor they choose for their Eye and Vision Care.

Systemic diseases are diseases that involve many organs or the whole body. Many of these diseases also affect the eyes. In fact, an eye exam sometimes leads to the first diagnosis of a systemic disease.

Why is the eye so important in systemic disease?

The eye is composed of many different types of tissue. This unique feature makes the eye susceptible to a wide variety of diseases as well as provides insights into many body systems. Almost any part of the eye can give important clues to the diagnosis of systemic diseases. Signs of a systemic disease may be evident on the outer surface of the eye (eyelids, conjunctiva and cornea), middle of the eye and at the back of the eye (retina).

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The optic nerve and eye movements often reflect changes in the central nervous system. This is because a large part of the brain helps provide visual information and controls eye movements. Because the eye structures are uniquely transparent, a doctor can see inside the eye. The eye is the only organ in the body in which a doctor can directly see blood vessels (particularly the small blood vessels and the underlying body tissues in their natural state). The health of the blood vessels (and body tissues) in the eye often indicates the condition of the blood vessels (arteries and veins) (and tissues) throughout the body.

Which systemic diseases most commonly affect the eye?

The eye may be involved in these diseases, among others:

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Diabetes mellitus – an imbalance in blood glucose (sugar) levels. Acquired immunodeficiency syndrome (AIDS) – a life-threatening disease caused by a virus that cripples the body’s immune defenses. Graves’ disease – a thyroid disorder, most often in women, which can cause a goiter (swelling in the front part of the neck) and protruding eyes. Sarcoidosis – a disease that mainly affects the lungs, brain, joints and eyes, found most often in young African-American women. Systemic lupus erythematosus – a connective tissue disorder involving mainly the skin, joints and kidneys. Rheumatoid Arthritis Hypertension (high blood pressure) Atherosclerosis (hardening of the arteries) Sickle cell disease – an inherited blood disorder that can block circulation throughout the body, primarily affectingAfrican-Americans Multiple sclerosis – a disease that damages nerve coverings, causing weakness, coordination and speech disturbances.

See a more detailed review of the importance of examination of the eye in systemic disease at: http://nationalmex.com/file/view/17732/why-the-eye-is-so-important-in-systemic-disease#.VVigpNh0zIU

Examples Include all aspects of eye, vision, and nervous system conditions involving the brain, cranial nerves, spinal cord, peripheral nerves, and corresponding muscles, i.e., multiple sclerosis, pituitary tumor, brain trauma, myasthenia gravis, papilledema, horner's syndrome, and numerous other organic and functional anomalies

Anatomically, a significant number of the twelve cranial nerves in the brain (seven of the twelve) are intricately and/or primarily involved with eye and vision function, as are numerous pathways in the cerebral cortex. Four of the twelve cranial nerves innervate the eye only, and three others innervate the eye and some other organ. As such the eye which is also the closest major organ to the brain, is directly innervated by seven of the twelve cranial nerves in addition to other brain processes. The eye has therefore often been described as an appendage of the brain.

It is a significant fact that most people never see a brain doctor (Neurologist) in their entire lifetime. They are usually referred to a Neurologist only after some neurological event is discovered or suspected by another practitioner. In contrast, many patients may see their eye doctor as much as several times each year, evidencing the fact that the best neurological exam most people ever receive is a good eye examination. This is the reason many neurological problems are first discovered through an eye examination.

While the eye is the physical conduit of vision, the cerebral hemispheres of brain is the actual place in the body where vision occurs and is interpreted. Likewise most of the motor functions of the eye are directly controlled by the cranial nerves.

Neurological deficits therefore can have many eye and visual consequences. A proper eye examination therefore is often the first examination to identify or discover a neurological problem. In addition, many eye and vision problems have their direct cause as a neurological deficit or neuro-physiological event.

In addition to its diagnostic modalities, Neuro-Optometry deals with related disorders which have a neurological etiology or base and benefits from Neuro-Optometric Rehabilitation. Neuro-Optometric Rehabilitation is the examination and treatment of adult and pediatric patients with visual dysfunction related to conditions like traumatic brain injury, stroke, cerebral palsy, multiple sclerosis, or brain tumor.

Neuro-visual problems can manifest as reading difficulties, visual inattention, eyestrain, double vision, visual memory problems, visually related anxiety, balance and postural difficulties, side vision loss, sensitivity to bright light, and other related symptoms or signs.

Neuro-Optometric Rehabilitation is an individualized treatment regimen for patients with Visual Deficits as a direct result of Physical Disabilities, Traumatic Brain Injuries, and other Neurological Insults. Neuro-Optometric Therapy is a process for the Rehabilitate of Visual/Perceptual/Motor Disorders. It includes, but is not limited to, Acquired Strabismus, Diplopia, Binocular Dysfunction, Convergence and/or Accommodation, Paresis/Paralysis, Oculomotor Dysfunction, Visual-Spatial Dysfunction, Visual Perceptual and Cognitive Deficits, Autism related eye & visual anomalies, and Traumatic Visual Acuity Loss.

Patients of all ages who have experienced Neurological Insults require Neuro-Optometric Rehabilitation. Visual problems caused by Traumatic Brain Injury, Cerebrovascular Accident, Cerebral Palsy, Multiple Sclerosis, etc., may interfere with performance causing the person to be identified as Learning Disabled or as having Attention Deficit Disorder. These Visual Dysfunctions can manifest themselves as psychological sequella such as Anxiety and Panic Disorders as well as Spatial Dysfunctions affecting balance and posture.

A Neuro-Optometric Rehabilitation treatment plan improves specific Acquired Vision Dysfunctions determined by standardized diagnostic criteria. Treatment regimens encompass medically necessary noncompensatory lenses and prisms with and without occlusion and other appropriate medical rehabilitate strategies.

Some of the more common Ocular and Vision problems involved with Neuro-Optometric care are:

Headaches
Blurred Vision (constant & intermittent)
Double Vision (constant & intermittent)
Eye Pain
Crossed or Turning Eyes (constant & intermittent)
Accommodative (Focusing) Dysfunctions
Binocular Vision Dysfunctions
Eye Movement Problems
Psychogenic Visual Disturbances
Psychoperceptual Disorders
Brain Injured Eye & Visual Disorders
Autism Related Visual Disorders
Low Vision Anomalies
School & Learning Related Problems

 See more information on Neuro Ophthalmic Disorders, Eye and Vision Care, and Vision Therapy

Due to the extensive reach of pediatric eye and vision care special training is necessary to adequately diagnose and treat the anomalies of pediatric eye and visual function. The following list details some of the more common categories of anomalies in pediatric eye & vision care.

Primary Ocular Diseases
Systemic Ocular Diseases
Neuro-Ophthalmic Disorders
Refractive Disorders
Binocular Disorders
Accommodative Dysfunctions
Amblyopias
Ocular Motility Disorders
Vision Development Anomalies
Psychogenic Visual Disturbances
Psychoperceptual Disorders
Vision Related Educational Dysfunctions

Neuro-Vision Evaluation in Pediatric Eye/Vision Care

A major problem with in pediatric eye care is the development of a child's visual system and the demands made upon it in the ever increasing competitive school environment. For a student to effectively compete in school and learning actvities their visual system should be in prime functional condition. This generally means that visual functions beyond the basic evaluation for clinical eye disease, and visual acuity must be evaluated.

Generally in a basic eye examination only eye disease and visual acuity is evaluated, and many children with other functional and school performance problems get a clean bill of ocular health and acuity but may still be visually deficient because they have not had all of the necessary elements of visual performance evaluated.

Many times classroom teachers will notice that school performance, reading difficulties, and deficient pycho-perceptual visual function persists in children who have supposedly had their eyes examined with given a clean report of Ocular-Vision function. Teachers are most important in detailing and recognizing such problems and should always be properly engaged in a Child's Ocular-Vision care if school performance is at question.

It is therefore most  important that school age children be properly and fully  evaluated. Parents should question the examining practitioner as to whether their examination specifically covers a detailed evaluation of the areas of Binocularity, Fusional and Accommodative disorders, and Pyscho-Perceptual Vision functions.

The in-depth evaluation of these functions will require additional evaluations beyond a general eye examination, and in our offices patients needing this type of evaluation are scheduled for a Neuro-Vision Evaluation. 

See more about pediatric eye vision care diagnosis & treatment, and School Performance Therapy.

About the Author - A former professor of pediatric eyecare and neuro-optometry, Dr. Hanna has been involved with clinical care and research in virtually all aspects of Pediatric Eye & Vision Care.

Pediatric eye/vision care requires special examination and treatment techniques. In addition to diseases and disorders of the eye and visual system which primarily affect children, special attention should be paid to the child's developing visual system.

In particular these developing systems and the stress placed upon them by the demands of school work cause tremendous problems with school and academic performance.

It is important that in addition to the examination for eye disease and eye sight as usually performed in a regular eye examination, other systems which control a child's focusing, eye teaming, eye tracking and visual perception be examined. These systems are extremely important to ensure that the child can compete with the demands and the visual stress involved in school work. Children who perform below standard in school many times show remarkable improvement with proper eye/vision care. Many times these children have had eye/vision screenings and regular eye/vision examinations which reveal no eye disease and normal 20/20 sight. They may have been given a clean bill of eye/visual health when in fact they have not been examined for many of the functions which would truly reveal their problem.

It is important to have the eye doctor check your child for proper function in the following six (6) areas:

1. PRIMARY AND SECONDARY EYE HEALTH

eye disease limited to the eye and eye disease caused by other systemic diseases or disorders.

2. REFRACTIVE STATUS

Eyeglass needs and measurement of clarity of sight.

3. ACCOMMODATIVE FUNCTION

focusing problems, particularly the stability, accuracy and ease of focusing.

4. BINOCULARITY

The teaming of both eyes in maintaining good depth perception and fusion under the stressful situations caused by reading, close work and concentrated school work.

5. OCULAR MOTILITY

The tracking of the eyes particularly in precise demands like reading.

6. VISUAL PERCEPTION

The function that allows the brain to interpret what the eyes see. In children this function is the last to develop fully. All of the physical attributes of vision may be fully functional yet the child may still have problems understanding what he or she sees. Dyslexia is a classic example of a visual perceptual problem.

If your child exhibits any of the following signs or symptoms you should immediately have the child checked by a Pediatric Optometrist:

eye disease
painful or itching eyes
watery eyes
red/pink eyes
double vision
rubbing eyes
Squinting
unsteady eye movement
constant or intermittent blurriness
Sleepiness when reading
Reversing words and letters
Skipping letters, words or lines when reading Excessive or abnormal blinking
head movement or turning when reading
Using a finger to follow the lines when reading skipping lines and words while reading discomfort from reading and school work
poor reading skills and comprehension
poor or recently reduced school performance

The most important fact to remember about your child's vision is that the child may have perfect eye health (no eye disease) and perfect clarity of eyesight (20/20) and still have significant vision problems, particularly the kinds of problems that can cause poor school performance.

WHAT YOU SHOULD KNOW ABOUT PROPER EYE EXAMINATIONS AND EYE CARE.

Consumers of health care in general and eye care in particular are increasingly confronted with advertising and gimmickry in the market place. Without an adequate knowledge of the essentials of proper eye care consumers are frequently in the position of the blind leading the blind in their search for proper eye care. It is important that eye care patients recognize that a thorough eye examination is the most important element of their primary level eye care, unfortunately most seem unaware of its importance. Consumers should be well educated about the elements of a thorough eye examination since it provides the basis for all other further care. In the increasing commercialization of health care and eye care in particular it is ironic that patients already visually at risk are bombarded with misinformation and advertising gimmickry which further clouds their ability to understand and see fact from fiction and gimmick from quality.

Patients seeking good eye care should ensure that the eye examination covers the six (6) major areas of ocular and visual function: Eye health, Refractive status, Ocular Motility, Binocularity, Accommodative Function, and Psycho/Perceptual Visual Function.

All areas of evaluation are essential for a proper general eye/vision evaluation of all patients. Unfortunately in practice many times only the first two areas are emphasized. In particular the evaluation of childrens' vision as it pertains to the development of the visual system and school performance requires careful evaluation of the last four areas. Also evaluation of these functions are critical for college students, those who use computers extensively or who other wise do a significant amount of near reading or close work. All of these types of patients may have excellent ocular health and 20/20 sight but may still have significant visual problems which may go undetected if these last four (4) areas of function are not adequately evaluated.

1. EYE HEALTH

The examination should cover 3 basic areas.

A. Primary eye disease, such as cataracts and glaucoma where the disease is limited entirely to the eye.

B. Eye disease or function secondary to neurological function. The eye in many aspects is an extension of the brain, and many primary neurological diseases may have one or several eye signs.

C. Eye disease or function secondary to systemic diseases. Many systemic disorders such as diabetes and hypertension may have one or more eye signs. Diabetes for example is the leading cause of blindness in the United States.

2. REFRACTIVE STATE

Examination of this function includes a measurement of visual acuity (ability for clear sight) at near and far distances e.g. 20/20, 20/50, 20/100 etc. This examination also requires measurement of the refractive error of the eye for both near and far distances. The refractive error is basically the correction needed for lenses to improve sight for nearsightedness, farsightedness, astigmatism and presbyopia. This area of testing is emphasized by many patients because it is the portion of the examination primarily responsible for the eyeglass prescription. It is important to note that such a prescription cannot be adequately determined without a thorough examination for eye disease since the refractive error may be intrinsically related to the health of the eye. Patients may have perfect 20/20 sight and still have significant eye disease.

3. OCULAR MOTILITY

The eyes should be examined for their ability to move in the orbits, for restriction of such movements and for accuracy, quickness, smoothness and facility in fixating on a target. Their ability to shift from one target to another and to follow a moving target should also be evaluated. Testing of these functions has significant neurological significance. deficiencies in these functions may cause problems with reading.

4. BINOCULARITY

Both eyes must be able to work together so that they aim and point at the same target, and function without undue effort to produce one image from the two images derived from both eyes. The convergence system is the primary system responsible for this binocularity of vision. This ability in humans to make one single image from the images from the two eyes is mediated by the brain. Certain interferences with ocular function may make it more difficult and in some cases impossible for the brain to perform this function of producing single vision. Differences of refractive state in the two eyes, functionally crossed or wall eyes, cranial nerve and muscle disorders, muscle tension and visual acuity imbalances between the two eyes may all cause such problems.

These problems may result in patients experiencing double vision, headaches, significant eye strain, use of only one eye, reduced depth perception, difficulty reading, and poor school performance.

Examination of the relationship between the two eyes for any problem which may interfere with the two eyes functioning as a team is therefore extremely important.

5. ACCOMMODATIVE FUNCTION

The eyes should be able to easily focus up close a certain degree or amount and to do so quickly from far to near and near to far. They should both focus at the same rate, do so accurately, and maintain a stable nonfluctuating level of focus or control of the system. This ability to focus or accommodate is the primary function responsible for the clarity of sight at differing distances. An inability to focus or to be able to maintain stable accurate focusing will cause significant blurry vision even though the patient may have no significant refractive error. Also the association and relationship of the accommodative system to the convergence system is of prime importance and needs to be fully evaluated. Evaluation of the ability of the eyes to focus and produce a clear sharp image without undue effort is therefore important to detect and resolve problems with intermittent or constant blurriness, eye strain, difficulty reading and at times poor performance with school work.

6. PSYCHO/PERCEPTUAL VISUAL FUNCTION

This area involves a wide range of potential problems including types of visual disturbances or dysfunction caused by emotional or psychological factors. Problems may also be primarily of a perceptual nature and may result in confusion and misunderstanding of information taken in through an intact and patent physical vision system. The visual perceptual functions allow the brain to interpret what the eyes see. In children these functions are generally the last to fully develop. All of the physical attributes of vision may be fully functional yet the child may still have problems understanding what he or she sees. In some cases Dyslexia is a classic example of a visual perceptual problem. Other visual perceptual problems may cause deficient visual memory, form, size and shape recognition, and visual figure ground. Because such problems may interfere with the learning process these problems are usually first discovered or suspected by astute teachers, special educators, speech therapists, school and educational psychologists or psychologists in the behavioral specialties. Resolution of these problems usually require further evaluation and treatment by optometric specialists with special training in Neuro-Optometry or Behavioral and Developmental Optometry. Many of these problems may also require a multidisciplinary approach utilizing various therapists and educators for adequate resolution.

Originally published at The Education Network Journal