Vitrectomy is a surgery to remove some or all of the vitreous humor

Vitreous humour

The vitreous humour or vitreous humor is the clear gel that fills the space between the lens and the retina of the eyeball of humans and other vertebrates...

 from the eye

Human eye

The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...

. Anterior vitrectomy entails removing small portions of the vitreous from the front structures of the eye—often because these are tangled in an intraocular lens or other structures. Pars plana vitrectomy is a general term for a group of operations accomplished in the deeper part of the eye, all of which involve removing some or all of the vitreous—the eye's clear internal jelly.

Pars plana vitrectomy

Originated by Robert Machemer and facilitated by Thomas M. Aaberg, Sr in late 1969 and early 1970, the original purpose of vitrectomy was to remove clouded vitreous—usually containing blood.
The success of these first procedures led to the development of techniques and instruments to remove clouding and also to peel scar tissue off the light sensitive lining of the eye—the retina

Retina

The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...

—membranectomy, to provide space for materials injected in the eye to reattach the retina such as gases or liquid silicone, and to increase the efficacy of other surgical steps such as scleral buckle

Scleral buckle

A scleral buckle is one of several ophthalmologic procedures that can be used to repair a retinal detachment. Retinal detachments are usually caused by retinal tears, and a scleral buckle can be used to close the retinal break....

.

An explosion of new instruments and surgical strategies through the 1970s and 1980s was spearheaded by surgeon/engineer Steve Charles, M.D. More recent advances have included smaller and more refined instruments for use in the eye, the injection of various medications at the time of surgery to manipulate a detached retina into its proper position and mark the location of tissue layers to allow their removal, and for long term protection against scar tissue formation.

Additional surgical steps

Additional surgical steps involved as part of modern vitrectomy surgeries may include:

Membranectomy – removal of layers of unhealthy tissue from the retina with minute instruments such as forceps (tiny grasping tools), picks (miniature hooks), and visco-discection (separating layers or tissue with jets of fluid.)

Fluid-air exchange – injection of air into the eye to remove the intraocular fluid from the Posterior Segment of the globe while maintaining IntraOcular Pressure to temporarily hold the retina in place or seal off holes in the retina. The air pressure is temporary as the Posterior Segment will soon re-fill with fluid.

Air-gas exchange – injection of gas, or more typically mixed gas and air, into the Posterior Segment of the globe. Typical gases used are perfluoropropane or sulfur hexafluoride

Sulfur hexafluoride

Sulfur hexafluoride is an inorganic, colorless, odorless, and non-flammable greenhouse gas. has an octahedral geometry, consisting of six fluorine atoms attached to a central sulfur atom. It is a hypervalent molecule. Typical for a nonpolar gas, it is poorly soluble in water but soluble in...

. The gases are mixed with air to neutralize their expansive properties to provide for a longer acting (than air alone) retinal tamponade. The retinal tamponade acts to hold the retina in place or temporarily seal off holes in the retina. The mixed gases disappear spontaneously once they have accomplished their purpose and the Posterior Segment re-fills with fluid.

Silicone oil injection – filling of the eye with liquid silicone to hold the retina in place.

Photocoagulation – laser treatment to seal off holes in the retina or to shrink unhealthy, damaging blood vessels which grow in some diseases such as diabetes.

Scleral buckling

Scleral buckle

A scleral buckle is one of several ophthalmologic procedures that can be used to repair a retinal detachment. Retinal detachments are usually caused by retinal tears, and a scleral buckle can be used to close the retinal break....

– placement of a support positioned like a belt around the walls of the eyeball to maintain the retina in a proper, attached position.

Lensectomy – removal of the lens in the eye when it is cloudy (cataract) or if it is attached to scar tissue.

Indications

Conditions which can benefit from vitrectomy include:

Vitreous floaters

Floater

Floaters are deposits of various size, shape, consistency, refractive index, and motility within the eye's vitreous humour, which is normally transparent. At young age the vitreous is perfectly transparent, but during life imperfections gradually develop. The common type of floater, which is...

– deposits of various size, shape, consistency, refractive index, and motility within the eye's normally transparent vitreous humour which can obstruct vision. Here pars plana vitrectomy has been shown to relieve symptoms. Because of possible side effects, however, it is used only in severe cases.

Retinal detachment

Retinal detachment

Retinal detachment is a disorder of the eye in which the retina peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. It is a medical emergency.The retina is a...

– a blinding condition where the lining of the eye peels loose and floats freely within the interior of the eye. Steps to reattach the retina may include vitrectomy to clear the inner jelly, scleral buckling to create a support for the reattached retina, membranectomy to remove scar tissue, injection of dense liquids to smooth the retina into place, photocoagulation to bond the retina back against the wall of the eye, and injection of a gas or silicone oil to secure the retina in place as it heals.

Macular pucker – formation of a patch of unhealthy tissue in the central retina (the macula

Macula

The macula or macula lutea is an oval-shaped highly pigmented yellow spot near the center of the retina of the human eye. It has a diameter of around 5 mm and is often histologically defined as having two or more layers of ganglion cells...

) distorting vision. Also called Epiretinal membrane

Epiretinal membrane

Epiretinal membrane is a disease of the eye in response to changes in the vitreous humor or more rarely, diabetes. It is also called macular pucker. Sometimes, as a result of immune system response to protect the retina, cells converge in the macular area as the vitreous ages and pulls away in...

. After vitrectomy to remove the vitreous gel, membranectomy is undertaken to peel away the tissue.

Diabetic retinopathy

Diabetic retinopathy

Diabetic retinopathy is retinopathy caused by complications of diabetes mellitus, which can eventually lead to blindness....

– may damage sight by either a non-proliferative or proliferative retinopathy. The proliferative type is characterized by formation of new unhealthy, freely bleeding blood vessels within the eye (called vitreal hemorrhage) and/or causing thick fibrous scar tissue to grow on the retina, detaching it. Often diabetic retinopathy is treated in early stages with a laser in the physician's office to prevent these problems. When bleeding or retinal detachment occur, vitrectomy is employed to clear the blood, membranectomy removes scar tissue, and injection of gas or silicon with scleral buckle may be needed to return sight. Diabetics should have an eye exam yearly.

Macular hole

Macular hole

A macular hole is a small break in the macula, located in the center of the eye's light-sensitive tissue called the retina.-Diagnosis:Macular degeneration is a condition affecting the tissues lying under the retina, while a macular hole involves damage from within the eye, at the junction between...

s – the normal shrinking of the vitreous with aging can occasionally tear the central retina causing a macular hole with a blind spot blocking sight.

Vitreous hemorrhage

Vitreous Hemorrhage

Vitreous Hemorrhage is the extravasation of blood into the areas in and around the vitreous humor of the eye. The vitreous humor is the clear gel that fills the space between the lens and the retina of the eye...

– bleeding in the eye from injuries, retinal tears, subarachnoidal bleedings (as Terson syndrome

Terson syndrome

Terson syndrome or Terson's syndrome is the occurrence of a vitreous hemorrhage of the human eye in association with subarachnoid hemorrhage. Vitreous hemorrhage of the eye can also occur in association with intracranial hemorrhage and elevated intracranial pressure . Intraocular hemorrhage can be...

),or blocked blood vessels. Once blood is removed, photocoagulation with a laser can shrink unhealthy blood vessels or seal retinal holes.

Complications of vitrectomy

Along with the usual complications of surgery, such as infections, vitrectomy can result in retinal detachment

Retinal detachment

Retinal detachment is a disorder of the eye in which the retina peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. It is a medical emergency.The retina is a...

. A more common complication is high intraocular pressure, bleeding in the eye, and cataract

Cataract

A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...

, which is the most frequent complication of vitrectomy surgery. Many patients will develop a cataract within the first few years after surgery.

Recovery after vitrectomy

Patients use eye drops for several weeks or longer to allow the surface of the eye to heal. In some cases heavy lifting is avoided for a few weeks. A gas bubble may be placed inside the eye to keep the retina in place. If a gas bubble is used, sometimes a certain head positioning has to be maintained, such as face down or sleeping on the right or left side. It is very important to follow the physician’s specific instructions. The gas bubble will dissolve over time, but this takes several weeks. Flying should be avoided while the gas bubble is still present. Problems such as return of the original condition, bleeding, or infection from the surgery may require additional treatment or can result in blindness. In the event that the patient would need to remain face down after surgery, a vitrectomy support system can be rented to help aid during the recovery time. This particular equipment may be used for as little as five days to as long as three weeks.

Vision after vitrectomy

The return of eyesight after vitrectomy depends on the underlying condition which prompted the need for surgery. If the eye is healthy but filled with blood, then vitrectomy can result in return of 20/20

20/20

20/20 is an American "television newsmagazine", , broadcast on ABC since June 6, 1978. Created by ABC News executive Roone Arledge, the show was designed similarly to CBS's 60 Minutes but focuses more on human interest stories than international and political subjects...

 eyesight. With more serious problems, such as a retina which has detached several times, final sight may be only sufficient to safely walk (ambulatory vision) or less.

Cultural references

In 1996, Spalding Gray

Spalding Gray

Spalding Rockwell Gray was an American actor, playwright, screenwriter, performance artist and monologuist...

 (June 5, 1941 – ca. January 10, 2004), an American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 actor

Actor

An actor is a person who acts in a dramatic production and who works in film, television, theatre, or radio in that capacity...

, screenwriter

Screenwriter

Screenwriters or scriptwriters or scenario writers are people who write/create the short or feature-length screenplays from which mass media such as films, television programs, Comics or video games are based.-Profession:...

 and playwright

Playwright

A playwright, also called a dramatist, is a person who writes plays.The term is not a variant spelling of "playwrite", but something quite distinct: the word wright is an archaic English term for a craftsman or builder...

,
released Gray's Anatomy, a film monologue describing his experiences dealing with a macular pucker and his decision to undergo surgery.