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A cornea transplant, also known as a corneal graft or penetrating keratoplasty, is a surgical procedure where a damaged or diseased cornea is replaced by a donor. The cornea is the clear part of eye in front of the iris and pupil. The surgeries are performed by ophthalmologists, medical doctors who specialize in eyes, and are often done on an outpatient basis (The patient goes home following surgery). Image File history File links Download high resolution version (801x512, 183 KB) Courtesy of Indiana University School of Medicine, Department of Ophthalmology File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
Image File history File links Download high resolution version (801x512, 183 KB) Courtesy of Indiana University School of Medicine, Department of Ophthalmology File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...
Surgical procedures have long and possibly daunting names. ...
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber and provides most of an eyes optical power [1]. Together with the lens, the cornea refracts light and consequently helps the eye to focus. ...
This article needs to be cleaned up to conform to a higher standard of quality. ...
Iris has three main meanings, unrelated except for their derivation from the Greek word for rainbow: Iris (mythology), a messenger of the gods in Greek mythology, identified with the rainbow Iris (anatomy), the sphincter around the pupil of the eye, named for the color in human and animal eyes Iris...
The human eye The pupil is the central transparent area (showing as black). ...
An optical refractor in use. ...
Indications
Indications for corneal transplantation include the following: - Optical - To improve visual acuity by replacing the opaque host tissue by clear healthy donor tissue. The most common indication in this category is pseudophakic bullous keratopathy, followed by keratoconus, corneal degeneration and dystrophy, as well as scarring due to keratitis and trauma.
- Tectonic/reconstructive - To preserve corneal anatomy and integrity in patients with stromal thinning and descemetoceles, or to reconstruct the anatomy of the eye, e.g. after corneal perforation.
- Therapeutic - To remove inflamed corneal tissue unresponsive to treatment by antibiotics or anti-virals.
- Cosmetic - To improve the appearance of patients with corneal scars that have given a whitish or opaque hue to the cornea. [1]
Keratoconus Keratoconus, or conical cornea (from kerato- cornea and conus cone), is an eye condition or disease in which the cornea thins and changes shape to be more like a cone than a parabola. ...
Trauma can : A serious and often body-altering physical injury, such as the removal of a limb. ...
An antibiotic is a drug that kills or slows the growth of bacteria. ...
Pre-operative examination In most instances, the patient will meet with their ophthalmologist for an examination in the weeks or months preceding the surgery. During the exam, the ophthalmologist will examine the eye and diagnose the condition. The doctor will then discuss the condition with the patient, including the different treatment options available. The doctor will also discuss the risks and benefits of the various options. If the patient elects to proceed with the surgery, the doctor will have the patient sign an informed consent form. The doctor might also perform a physical examination and order lab tests, such as blood work, X-rays, or an EKG. In semantics, the patient is the passive part of a process. ...
Informed consent is a legal condition whereby a person can be said to have given consent based upon an appreciation and understanding of the facts and implications of any actions. ...
In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz...
ECG may also refer to the East Coast Greenway Lead II An Electrocardiogram (ECG or EKG, abbreviated from the German Elektrokardiogramm) is a graphic produced by an electrocardiograph, which records the electrical voltage in the heart in the form of a continuous strip graph. ...
The surgery date and time will also be set, and the patient will be told where the surgery will take place.
Procedure On the day of the surgery, the patient arrives to either a hospital or an outpatient surgery center, where the procedure will be performed. The patient is given a brief physical examination by the surgical team and is taken to the operating room. In the OR, the patient lays down on an operating table and is either given general anesthesia, or local anesthesia and a sedative. A typical modern surgery operation For other meanings of the word, see Surgery (disambiguation) Surgery (from the Greek cheirourgia - lit. ...
A physician visiting the sick in a hospital. ...
An operating theatre or operating room is a room within a hospital within which surgical operations are carried out. ...
In modern medical practice, general anaesthesia is a complex procedure involving: preanaesthetic assessment administration of general anaesthetic drugs cardirespiratory monitoring analgesia airway management fluid management Contents // Categories: Anesthesia | Medicine stubs ...
Local anesthesia is any technique to render part of the body insensitive to pain without affecting consciousness. ...
A sedative is a drug that depresses the central nervous system (CNS), which causes calmness, relaxation, reduction of anxiety, sleepiness, slowed breathing, slurred speech, staggering gait, poor judgment, and slow, uncertain reflexes. ...
With anesthesia induced, the surgical team prepares the eye to be be operated on and drapes the face around the eye. An eyelid speculum is placed to keep the lids open, and some lubrication is placed on the eye to prevent drying. A metal ring is then stitched to the sclera, which will provide a base for a trephine. Meanings of speculum include: A medical tool used for examing body cavities; see Speculum (medical). ...
The sclera is the white outer coating of the eye. ...
A trephine is a surgical instrument. ...
A trephine is then placed over the cornea and is used by the surgeon to cut the host cornea. The trephine is then removed and the surgeon cuts a circular graft (a "button") from the donor cornea. Once this is done, the surgeon returns to the patient's eye and removes the host cornea. In medicine, grafting is a surgical procedure to transplant tissue without a blood supply. ...
The donor cornea is then brought into the surgical field and manuvered into place with forceps. Once in place, the surgeon will fasten the cornea to the eye with a running stitch (as used in the image above) or a multiple interrupted stiches. The surgeon finishes up by reforming the anterior chamber with a sterile solution injected by a canula, then testing that it's watertight by placing a dye on the wound exterior. Forceps are a hand-held instrument for grasping and holding objects, similar in concept to tongs, tweezers or pincers. ...
A cannula (pl. ...
With the metal ring removed and antibiotic eyedrops placed, the eye is patched, and the patient is taken to a recovery area while the effects of the anesthesia wear off. The patient typically goes home following this and sees the doctor the following day for the first post operative appointment. An antibiotic is a drug that kills or slows the growth of bacteria. ...
Risks As with any surgery, there are some possible risks. While the cornea itself doesn't have any blood vessels, there is still a potential for some blood loss, usually from suturing the metal ring to the sclera. Any blood loss is typically less than a teaspoon, or less than 2 cc. When used as a quantity, such as in a recipe, a teaspoon is the name of several units of measuring volume used primarily in cooking. ...
There is also a risk of infection. Since the cornea has no blood vessels (it takes its nutrients from the aqueous humor) it takes longer to heal than would a cut on the skin. While the wound is healing, it is possible that it might become infected by various microorganisms. This risk is minimized by antibiotic prophylaxis (using antibiotic eyedrops, even when no infection exists). An infection is the detrimental colonization of a host organism by a foreign species. ...
The aqueous humour is the clear, watery fluid that fills the complex space in the front of the eye which is bounded at the front by the cornea and at the rear by the front surface or face of the vitreous humour. ...
A wound is a physical trauma where the skin is torn, cut or punctured. ...
A microorganism or microbe is an organism that is so small that it is microscopic (invisible to the naked eye). ...
Prophylaxis refers to any medical or public health procedure whose purpose is to prevent, rather than treat or cure, disease. ...
Graft failure can occur at any time after the cornea has been transplanted, even years or decades later. The causes can vary, though it is usually due to new injury or illness. Treatment can be either medical or surgical, depending on the individual case.
Prognosis When the primary purpose of a cornea transplant is to improve visual acuity, the prognosis is dependent upon whether the rest of the eye is healthy. If the rest of the eye is healthy, then it should be possible to recover normal vision.
History The first cornea transplant was first performed in 1905, by Dr. Eduard Zirm, making it one of the first types of transplant surgery successfully performed. On December 7, 1905 Dr. Eduard Zirm, the Chief of Medicine of the hospital in Olomouc (now in Moravia in the Czech Republic) and representative of the famous Medical School in Vienna, was able to do what had previously been impossible: He performed the first successful organ transplant*. The cornea...
Advances in microscopes enabled surgeons to get a better view of the surgical field, while advances in materials science enabled them to use sutures finer than a human hair. A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ...
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Sutures are the stitches doctors, and especially surgeons, use to hold skin, organs, blood vessels and all other tissues of the human body together, after they have been severed in minor or major surgery. ...
Instrumental in the success of cornea transplants were the establishment of eye banks. These are organizations located throughout the world to coordinate the distribution of donated corneas to surgeons, as well as providing eyes for research. Some eye banks also distribute other anatomical gifts. Organ donation is the removal of specific tissues of the human body from a person who has recently died, or from a living donor, for the purpose of transplanting them into other persons. ...
See also The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber and provides most of an eyes optical power [1]. Together with the lens, the cornea refracts light and consequently helps the eye to focus. ...
This article needs to be cleaned up to conform to a higher standard of quality. ...
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