Ophthalmology is the branch of medicine which deals with the anatomy, functions, and diseases of the eye. The term ophthalmologist refers to a specialist in medical and surgical eye problems. Since ophthalmologists perform operations on eyes, they are considered to be both a surgical and medical specialty.

The word ophthalmology comes from the Greek roots ophthalmos meaning eye and logos meaning word, thought or discourse; ophthalmology literally means "the science of eyes". "Opthomology" is a common mis-hearing or mis-remembering of the term. As a discipline, it applies to animal eyes also, since the differences from human practice are surprisingly minor and are related mainly to differences in anatomy or prevalence, not differences in disease processes. However, veterinary medicine is regulated separately in many countries and states/provinces resulting in few ophthalmologists treating both humans and animals.

Of all the branches of Islamic medicine, ophthalmology was considered one of the foremost. It was during this period that ophthalmology began being treated as an independent medical discipline in its own right. As such, medieval islamic physicians are considered founders of ophthalmology as an independent discipline. One of the pioneers of ophthalmology was the great Persian physician Rhazes. Scores of specialized instruments were developed. Innovations such as the “injection syringe”, invented by the Iraqi physician Ammar ibn Ali of Mosul, which was used for the extraction by suction of soft cataracts, were quite common. In cataract surgery, Ammar ibn Ali attempted the earliest extraction of cataracts using suction. He introduced a hollow metallic syringe hypodermic needle through the sclera and successfully extracted the cataracts through suction.

Ibn al-Haytham (Alhazen) wrote extensively on optics and the anatomy of the eye in his Book of Optics (1021). He was the first to hint at the retina being involved in the process of image formation.

Ibn al-Nafis, in The Polished Book on Experimental Ophthalmology, discovered that the muscle behind the eyeball does not support the ophthalmic nerve, that they do not get in contact with it, and that the optic nerves transect but do not get in touch with each other. He also discovered many new treatments for glaucoma and the weakness of vision in one eye when the other eye is affected by disease.[6] Salah–ud-din bin Youssef al-Kalal bi Hama (i.e. the eye doctor of Hama) was a Syrian oculist who flourished in Hama in 1296. He wrote for his son a very elaborate treatise of ophthalmology entitled Nur al-Uyun wa Jami al-Funun (light of the eyes and collection of rules).

 

The seventeenth and eighteenth century saw the use of hand lenses (by Malpighi), microscopes (van Leeuwenhoek), preparations for fixing the eye for study (Ruysch) and later the freezing of the eye (Petit). This allowed for detailed study of the eye and an advanced model. Some mistakes persisted such as: why the pupil changed size (seen to be vessels of the iris filling with blood), the existence of the posterior chamber, and of course the nature of the retina. In 1722 Leeuwenhoek noted the existence of rods and cones though they were not properly discovered until Gottfried Reinhold Treviranus in 1834 by use of a microscope.
[edit] Ophthalmic surgery in Great Britain

The first ophthalmic surgeon in Great Britain was John Freke, appointed to the position by the Governors of St Bartholomew's Hospital in 1727, but the establishment of the first dedicated ophthalmic hospital in 1805; now called Moorfields Eye Hospital in London, England was a transforming event in modern ophthalmology. Clinical developments at Moorfields and the founding of the Institute of Ophthalmology by Sir Stewart Duke Elder established the site as the largest eye hospital in the world and a nexus for ophthalmic research.

At a more integrative level, the primary function of the nervous system is to control the body. It does this by extracting information from the environment using sensory receptors, sending signals that encode this information into the central nervous system, processing the information to determine an appropriate response, and sending output signals to muscles or glands to activate the response. The evolution of a complex nervous system has made it possible for various animal species to have advanced perception abilities such as vision, complex social interactions, rapid coordination of organ systems, and integrated processing of concurrent signals. In humans, the sophistication of the nervous system makes it possible to have language, abstract representation of concepts, transmission of culture, and many other features of human society that would not exist without the human brain.

Neurons and synapses

Most neurons send signals via their axons, although some types are capable of dendrite-to-dendrite communication. (In fact, the types of neurons called amacrine cells have no axons, and communicate only via their dendrites.) Neural signals propagate along an axon in the form of electrochemical waves called action potentials, which produce cell-to-cell signals at points where axon terminals make synaptic contact with other cells.

Synapses may be electrical or chemical. Electrical synapses make direct electrical connections between neurons,but chemical synapses are much more common, and much more diverse in function. At a chemical synapse, the cell that sends signals is called presynaptic, and the cell that receives signals is called postsynaptic. Both the presynaptic and postsynaptic areas are full of molecular machinery that carries out the signalling process. The presynaptic area contains large numbers of tiny spherical vessels called synaptic vesicles, packed with neurotransmitter chemicals. When the presynaptic terminal is electrically stimulated, an array of molecules embedded in the membrane are activated, and cause the contents of the vesicles to be released into the narrow space between the presynaptic and postsynaptic membranes, called the synaptic cleft. The neurotransmitter then binds to receptors embedded in the postsynaptic membrane, causing them to enter an activated state. Depending on the type of receptor, the resulting effect on the postsynaptic cell may be excitatory, inhibitory, or modulatory in more complex ways. For example, release of the neurotransmitter acetylcholine at a synaptic contact between a motor neuron and a muscle cell induces rapid contraction of the muscle cell. The entire synaptic transmission process takes only a fraction of a millisecond, although the effects on the postsynaptic cell may last much longer (even indefinitely, in cases where the synaptic signal leads to the formation of a memory trace).

 

Ophthalmologists are medical doctors (M.D. or D.O., not O.D.) who have completed a college degree, medical school,additional residency and internship training and further additional four to five years of postgraduate training in ophthalmology. In many countries, ophthalmologists also undergo additional specialized training in one of the many subspecialities. Ophthalmology was the first branch of medicine to offer board certification, now a standard practice among all specialties.
[edit] Australia and New Zealand

In Australia and New Zealand, the FRACO/FRANZCO is the equivalent postgraduate specialist qualification. It is a very competitive speciality to enter training and has a closely monitored and structured training system in place over the five years of postgraduate training. Overseas-trained Ophthalmologists are assessed using the pathway published on the RANZCO website. Those who have completed their formal training in the UK and have the CCST/CCT are usually deemed to be comparable.
Canada

In Canada, an Ophthalmology residency after medical school is undertaken. The residency lasts a minimum of five years after the MD degree although subspecialty training is undertaken by about 30% of fellows (FRCSC). There are about 30 vacancies per year for ophthalmology training in all of Canada.
Finland

In Finland, physicians willing to become Ophthalmologists must undergo a five year specialization which includes practical training and theoretical studies.
Germany

In Germany, physicians willing to become Ophthalmologists must undergo a five year specialization of practical training.
India

In India, after completing MBBS degree, post-graduation in Ophthalmology is required. The degrees are Doctor of Medicine (MD), Master of Surgery (MS), Diploma in Ophthalmic Medicine and Surgery (DOMS) or Diplomate of National Board (DNB). The concurrent training and work experience is in the form of a Junior Residency at a Medical College, Eye Hospital or Institution under the supervision of experienced faculty. Further work experience in form of fellowship, registrar or senior resident refines the skills of these eye surgeons. All India Ophthalmological Society (AIOS) and various state level Ophthalmological Societies (like DOS) hold regular conferences and actively promote continuing medical education. Royal colleges of the united kingdom, mainly Royal college of surgeons of Edinburgh (RCSEd), Royal College of ophthalmologists (RCOphth)[dead link] and Royal college of physicians and Surgeons of Glasgow (RCPSG) are conducting their fellowship and membership examinations since mid 1990s and awarding fellowships and memberships to the successful candidates.
Pakistan

In Pakistan, after MBBS, a 2 year residency programme leads to FCPS in Ophthalmology. Moreover, MCPS and DOMS are also being offered.[1] M.S.(Ophthalmology) is also one of the specialty programmes. In addition to programmes for Doctors, various diplomas and degrees for Opticians are also being offered to produce competent Optic technicians in this field. These programmes are being offered notably by Punjab Institute of Preventive Ophthalmology (PIPO) Lahore,Pakistan.[2] Sub-specialty Fellowships are also being offered in the field of Pediatric Ophthalmology and Vitreo-Retinal Ophthalmology.
Philippines

Ophthalmology is a considered a medical specialty that uses medicine and surgery to treat diseases of the eye. To become a general ophthalmologist, a candidate must have completed a Doctor of Medicine degree or its equivalent (e.g. MBBS...), have passed the physician licensure exam, completed an internship in medicine, and completed residency at any Philippine Academy of Ophthalmology (PAO)[7] accredited program. Attainment of board certification in ophthalmology from PBO is optional, but is preferred and required to gain privileges in most major health institutions. Graduates of residency programs can receive further training in subspecialties of ophthalmology such as neuro-ophthalmology, etc. by completing a fellowship program which varies in length depending on each program's requirements. The leading professional organization in the country is the Philippine Academy of Ophthalmology[8] which also regulates ophthalmology residency programs and board certification through its accrediting agency, the Philippine Board of Ophthalmology.
United Kingdom and Republic of Ireland

In the United Kingdom, there are three colleges that grant postgraduate degrees in ophthalmology. The Royal College of Ophthalmologists grants MRCOphth and FRCOphth (postgraduate exams), the Royal College of Edinburgh grants MRCSEd, the Royal College of Glasgow grants FRCS. In Ireland the Royal College of Ireland grants FRCSI. Work experience as a specialist registrar and one of these degrees is required for specialisation in eye diseases.
United States

In the United States, four years of residency training after medical school are required, with the first year being an internship in surgery, internal medicine, pediatrics, or a general transition year. Optional fellowships in advanced topics may be pursued for several years after residency. Most currently practicing ophthalmologists train in medical residency programs accredited by the Accreditation Council for Graduate Medical Education (ACGME) and are board certified by the American Board of Ophthalmology. Some physicians train in osteopathic medical schools may hold a Doctor of Osteopathy ("DO") degree rather than an MD. The same residency and certification requirements for ophthalmology training must be fulfilled by osteopathic physicians. Completing the requirements of continuing medical education is mandatory for continuing licensure and re-certification. Professional bodies like the AAO and ASCRS organize conferences and help members through continuing medical education programs to maintain certification, in addition to political advocacy and peer support.

Ophthalmology includes sub-specialities which deal either with certain diseases or diseases of certain parts of the eye. Some of them are:

* Anterior segment surgery
* Cataract — not usually considered a subspecialty per se, since most general ophthalmologists perform cataract surgery
* Cornea, ocular surface, and external disease
* Glaucoma
* Medical retina, deals with treatment of retinal problems through non-surgical means.
* Neuro-ophthalmology
* Ocular oncology
* Oculoplastics & Orbit surgery
* Ophthalmic pathology
* Pediatric ophthalmology/Strabismus (mis-alignment of the eyes)
* Refractive surgery
* Uveitis/Immunology
* Veterinary Formal specialty training programs in veterinary ophthalmology now exist in some countries.[9][10][11]
* Vitreo-retinal surgery, deals with surgical management of retinal and posterior segment diseases and disorders. Medical retina and vitreo-retinal surgery sometimes together called posterior segment subspecialisation.

Ophthalmic surgery
For a comprehensive list of surgeries performed by ophthalmologists, see eye surgery.
Notable ophthalmologists

This is an incomplete list, which may never be able to satisfy particular standards for completeness. You can help by expanding it with reliably sourced entries.

See also: :Category:Ophthalmologists
Pre-18th century

* Detailed descriptions of delicate cataract surgery with sophisticated needle syringes is contained in the medical writings of Celsus (A.D. 14-37)
* Marie Colinet, wife of Wilhelm Fabry, employs a magnet for removing a foreign body from the eye, 1627.

18th-19th century

* Sir William Adams (UK) Founder of Exeter's West of England Eye Infirmary.
* Carl Ferdinand von Arlt (1812–1887), the elder (Austrian) proved that myopia is largely due to an excessive axial length, published influential textbooks on eye disease, and ran annual eye clinics in needy areas long before the concept of volunteer eye camps became popular. His name is still attached to some disease signs, e.g., von Arlt's line in trachoma. His son Ferdinand Ritter von Arlt, the younger, was also an ophthalmologist.
* Jacques Daviel (France) claimed to be the 'father' of modern cataract surgery in that he performed extracapsular extraction instead of needling the cataract or pushing it back into the vitreous. It is said that he carried out the technique on 206 patients in 1752-3, out of which 182 were reported to be successful. These figures are not very credible, given the total lack of both anaesthesia and aseptic technique at that time.
* Frans Cornelis Donders (1818–1889) (Dutch) published pioneering analyses of ocular biomechanics, intraocular pressure, glaucoma, and physiological optics. Made possible the prescribing of combinations of spherical and cylindrical lenses to treat astigmatism.
* Albrecht von Graefe (1828–1870) (Germany) Along with Helmholtz and Donders, one of the 'founding fathers' of ophthalmology as a specialty. A brilliant clinician and charismatic teacher who had an international influence on the development of ophthalmology. A pioneer in mapping visual field defects and diagnosis and treatment of glaucoma. Introduced a cataract extraction technique that remained the standard for over 100 years, and many other important surgical techniques such as iridectomy. Rationalised the use of many ophthalmically important drugs, including mydriatics & miotics. The founder of the one of the earliest ophthalmic societies (German Ophthalmological Society, 1857) and one of the earliest ophthalmic journals (Graefe's Archives of Ophthalmology). The most important ophthalmologist of the nineteenth century.
* Allvar Gullstrand (Sweden), Nobel Prize winner in 1911 for his research on the eye as a light-refracting apparatus. Described the schematic eye a mathematical model of the human eye based on his measurements known as the optical constants of the eye. His measurements are still used today.
* Hermann von Helmholtz, great German polymath, invented the ophthalmoscope (1851) and published important work on physiological optics, including colour vision (1850s).
* Hermann Snellen (Netherlands) introduced the Snellen chart to study visual acuity.
* Sir Arthur Conan Doyle (United Kingdom). English writer, primarily of the Sherlock Holmes stories. Trained in but apparently never practiced Ophthalmology.
* Jose Rizal (Philippines). The Philippines National Hero was a Ophtalmologist, One of his works was operation of his mother's eye for twice from cataract.