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Vitrectomy

vitrctomy

Vitrectomy

 
 
 
Vitrectomy

 

 
  

Vitrectomy is surgery to remove some or all of the vitreous humor from the eye.

Anterior vitrectomy entails removing small portions of the vitreous humor 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 humor—the eye's clear internal jelly.

Even before the modern era, some surgeons performed crude vitrectomies. For instance, Dutch surgeon Anton Nuck (1650–1692) claimed to have removed vitreous by suction in a young man with an inflamed eye. In Boston, John Collins Warren (1778–1856) performed a crude limited vitrectomy for angle closure glaucoma.

Anesthesia for vitrectomy

 

Single port 19-gauge vitrectomy

Options for anesthesia for vitrectomy are general anaesthesia, local anesthesia, topical anesthesia and Trojan Horse anesthesia (Augmented topical anesthesia).

Each anesthesia technique has its advantages and disadvantages, and the selection of anesthesia will depend on various factors including the surgeon's and patient's choice, disease and additional surgical steps required.

Pars plana vitrectomy

Vitrectomy was originated by Robert Machemer with contributions from Thomas M. Aaberg, Sr in late 1969 and early 1970. The original purpose of vitrectomy was to remove clouded vitreous humor—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—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.

The development 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

 

Vitrectomy instruments

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-dissection (separating layers of 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. 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 – 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.

Vitrectomy iran

Indications

Conditions which can benefit from vitrectomy include:

Retinal detachment – 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) distorting vision. Also called epiretinal membrane. After vitrectomy to remove the vitreous gel, membranectomy is undertaken to peel away the tissue.

Diabetic retinopathy – 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 silicone with scleral buckle may be needed to return sight. Diabetics should have an eye exam yearly.

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

Vitreous hemorrhage – bleeding in the eye from injuries, retinal tears, subarachnoid hemorrhages (as Terson syndrome), or blocked blood vessels. Once blood is removed, photocoagulation with a laser can shrink unhealthy blood vessels or seal retinal holes.

Vitreous floaters – deposits of various size, shape, consistency, refractive index, and motility within the eye's normally transparent vitreous humor 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.

 

Complications

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

A more common complication is high intraocular pressure, bleeding in the eye, and cataract, which is the most frequent complication of vitrectomy surgery. Many patients will develop a cataract within the first few years after surgery.

Because there have been no published controlled trials evaluating the benefits and risks stemming from post vitrectomy cataract surgery, ophthalmologists have no clear evidence to rely upon, when counseling patients about cataract surgery.

iranian surgeryRecovery after vitrectomy


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 (
posturing) has to be maintained, such as face down or sleeping on the right or left side. The gas bubble will dissolve over time, but this takes several weeks. Flying should be avoided while the gas bubble is still present.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.

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


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

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

 

10 common question about vitrectomy surgery

1How long does it take to clear vision after vitrectomy?
You might have some pain in your eye and your vision may be blurry for a few days after the surgery. You will need 2 to 4 weeks to recover before you can do your normal activities again. It may take longer for your vision to get back to normal
2What is vitrectomy surgery like?
Vitrectomy is a surgical procedure undertaken by a specialist where the vitreous humor gel that fills the eye cavity is removed to provide better access to the retina. This allows for a variety of repairs, including the removal of scar tissue, laser repair of retinal detachments and treatment of macular holes.
3How long does vitrectomy surgery take?
Some of the more common conditions that are treated include retinal detachments, diabetic retinopathy, macular hole, complications from cataract surgery and infections inside the eye. The length of the vitrectomy depends on the problem you have. Time for surgery can be from 30 minutes to over 3 hours.
4Is vitrectomy major surgery?
Vitrectomy surgeries involve the removal and replacement of some or all of the vitreous humor or fluid from the eye. The procedure is considered very successful and is often done as part of other eye surgeries.
5Can a vitrectomy be done twice?
A vitrectomy is a type of eye surgery to treat various problems with the retina and vitreous. During the surgery, your surgeon removes the vitreous and replaces it with another solution. ... Scar tissue in your vitreous can also displace or tear your retina. All of this can impair vision.
6Are you awake during vitrectomy?
Vitrectomy is typically performed under local (injection) anesthesia, with sedation. In other words, the patient is awake during the procedure, but does not feel pain or see the procedure being performed.
7Does vitrectomy remove all floaters?
Outpatient surgery with local anesthesia can be utilized during vitrectomy to remove floaters and vitreous debris. During this procedure, nearly all the vitreous is removed, and with it, almost all of the vitreous opacities.
8When can I drive after vitrectomy?
We advise you not to drive for two weeks after the procedure. If gas has been injected in your eye to support the retina, you will not be able to drive for about six to eight weeks. This is because of the effects the gas may have on your eye during that time.
9Do floaters come back after vitrectomy?
However, most eye floaters don't require treatment. Eye floaters can be frustrating, and adjusting to them can take time. Once you know the floaters will not cause any more problems, you may eventually be able to ignore them or notice them less often.
10Is epiretinal membrane serious?
An epiretinal membrane will not cause total blindness – it will typically only affect the central vision in the affected eye, while peripheral or 'side' vision remains unaffected. ... In other cases, the epiretinal membrane may worsen over time, causing blurring and distortion to the central part of your vision.

Vitrectomy

Vitrectomy
 

Vitrectomy is surgery to remove some or all of the vitreous humor from the eye.

Anterior vitrectomy entails removing small portions of the vitreous humor 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 humor—the eye’s clear internal jelly.

Even before the modern era, some surgeons performed crude vitrectomies. For instance, Dutch surgeon Anton Nuck (1650–1692) claimed to have removed vitreous by suction in a young man with an inflamed eye. In Boston, John Collins Warren (1778–1856) performed a crude limited vitrectomy for angle closure glaucoma.

Anesthesia for vitrectomy

Single port 19-gauge vitrectomy

Options for anesthesia for vitrectomy are general anaesthesia, local anesthesia, topical anesthesia and Trojan Horse anesthesia (Augmented topical anesthesia).

Each anesthesia technique has its advantages and disadvantages, and the selection of anesthesia will depend on various factors including the surgeon’s and patient’s choice, disease and additional surgical steps required.

Pars plana vitrectomy

Vitrectomy was originated by Robert Machemer with contributions from Thomas M. Aaberg, Sr in late 1969 and early 1970. The original purpose of vitrectomy was to remove clouded vitreous humor—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—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.

The development 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

Vitrectomy instruments

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-dissection (separating layers of 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. 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 – 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.

Vitrectomy iran

Indications

Conditions which can benefit from vitrectomy include:

Retinal detachment – 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) distorting vision. Also called epiretinal membrane. After vitrectomy to remove the vitreous gel, membranectomy is undertaken to peel away the tissue.

Diabetic retinopathy – 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 silicone with scleral buckle may be needed to return sight. Diabetics should have an eye exam yearly.

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

Vitreous hemorrhage – bleeding in the eye from injuries, retinal tears, subarachnoid hemorrhages (as Terson syndrome), or blocked blood vessels. Once blood is removed, photocoagulation with a laser can shrink unhealthy blood vessels or seal retinal holes.

Vitreous floaters – deposits of various size, shape, consistency, refractive index, and motility within the eye’s normally transparent vitreous humor 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.

 

Complications

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

A more common complication is high intraocular pressure, bleeding in the eye, and cataract, which is the most frequent complication of vitrectomy surgery. Many patients will develop a cataract within the first few years after surgery.

Because there have been no published controlled trials evaluating the benefits and risks stemming from post vitrectomy cataract surgery, ophthalmologists have no clear evidence to rely upon, when counseling patients about cataract surgery.

iranian surgeryRecovery after vitrectomy


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 (
posturing) has to be maintained, such as face down or sleeping on the right or left side. The gas bubble will dissolve over time, but this takes several weeks. Flying should be avoided while the gas bubble is still present.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.

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


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

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

 

 

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