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This is an effort from Neoretina Eyecare Institute to
provide the right information that makes your more knowledgable about your eyes.
 

Surgeries

 

Vitrectomy
Vitrectomy is a surgery to remove some or all of the vitreous humor from the eye.
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.
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Pars plana vitrectomy
Pars planaviterctomy is a surgery for removal of vitreous body in the eye for adequate access to the deeper layers of the retina.It is usually done by making three openings (port) in the region of parsplana in the eye ball ,one opening is for continuous infusion of the other two one is for illumination and other is for active instuments.Occassionally 2 port and 4 port vitrectomy may be done based on the condition.Based on the size of these openings there is 20 guage, 23 guage(sutureless) and 25 guage (sutureless) vitrectomies have been described.

Additional  surgical steps:
Additionalsurgical steps involved as part of modern vitrectomy surgeries may include:
Membrane peeling – 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 hexa fluoride. 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(as a part of vitreoretinal surgery) – 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 total  when it is cloudy (cataract) or as a part of vitreoretinal surgery
 Indications
Conditions which can benefit from vitrectomy include:
Vitreous floaters – 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 – 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 silicon with scleral buckle may be needed to return sight. Diabetics should have an eye exam yearly.
Macular holes – the normal shrinking of the vitreous with aging can occasionally tear the central retina causing a macular hole with a blind spot blocking sight.the surgery involves peeling of inner limiting membrane followed by gas injection.
Vitreous hemorrhage – bleeding in the eye from injuries, retinal tears, subarachoroidal bleedings (as tersons syndrome),or blocked blood vessels. Once blood is removed, photocoagulation with a laser can shrink unhealthy blood vessels or seal retinal holes.

Procedure:
Vitrectomy procedure in adults is done under monitored local anaesthesia. Local anaesthesia involves peribulbarinjection(injection to the outside of the eye ) achieving complete movement free and sensation free eye. Anaesthetist is present in the OR monitoring other vital parameters and making the patient comfortable.
Depending on the guage of the instruments there are three types of vitrectomy surgeries are possible. 20G has been the standard size of the vitrectomy instruments and classically since the beginning of the vitrectomy surgeries this involved making tiny incisions on the conjunctiva and then sclera and the end of the surgery there are closed with suture. This has classically been called 20G pars plana vitrectomy.
Currently with refining of the instruments and availability of smaller guage instruments and wound constructions 23 G and 25 G vitrectomies are possible and are routinely offered to the patients. 23 aswell as 25 G vitreous surgeries doent involve making incisions on the conjunctiva and the wound on the sclera is generally self sealing, so sometimes more appropriatelt these surgeries are called transconjunctivalsuturelessvitrectomies.
The definite  advantage these sutureless surgeries over the conventional surgeries is faster healing and faster visual rehabilitation, but the ultimate visual recovery will be remaining same.
Complications of vitrectomy
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.
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. Air travel 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 loss of vision. 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 and central portion of retina called macula is un affected but filled with blood, then vitrectomy can result in return of 20/20 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.
 

23 guage sutureless vitrectomy

23 guage sutureless vitrectomy

Scleral buckling
A scleral buckle is one of two main procedures that are commonly used to repair retinal detachment. Retinal detachments are usually caused by retinal tears, and a scleral buckle can be used to close the retinal break.
Scleral buckles come in many shapes and sizes. An encircling band is a thin silicone band sewn around the circumference of the eye ball . Buckles are often placed under a band to create a dimple on the eye wall.
The scleral buckle is secured around the eyeball under the conjunctiva. This moves the wall of the eye closer to the detached retina. It also may move the retina closer to the vitreous. This alteration in the relationships of the tissues seems to allow the fluid which has formed under the retina to be pumped out, and the retina to re-attach. The physics and physiology   of this process are not fully understood.
Retinal detachment surgery usually also involves the use of cryotherapy or phoyocoagulation. The laser or cryotherapy forms a permanent adhesion around the retinal break and prevent further accumulation of fluid and re-detachment.
Occassionally gas or air may be injected into the vitreous cavity at the end of the surgery,in such cases Air travel should be avoided while the gas bubble is present in the vitreous cavity.
Scleral buckles are done using local or general and are often done as  procedures. In the majority of treatments the buckle is left in place permanently, although in some instances the buckles can be removed after the retina heals. The buckle may also be removed in the event of infection.
Vision after Scleral Buckle
The return of eyesight after  Scleral Buckle depends whether  central portion of retina called macula is attached or detached at the time of the surgery,it also depends on the duration of the retinal detachment, if macula attached at the time of surgery can result in return of 20/20 eyesight.


 















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