Definition & Overview
Vitrectomy, also known as macular hole surgery, is a procedure for removing the vitreous gel from the eye to treat several serious eye conditions and restore vision.
The vitreous gel, or vitreous humour, is a clear gel mostly composed of water. It contains a small amount of hyaluronic acid, a substance that acts as a lubricant, and other types of protein. The jelly-like property of the vitreous is due to the presence of fine collagen fibrils that give it form and density. The vitreous, which contributes to the spherical shape of the eye, is located between the lens and retina, providing support and cushion to these parts of the eye.
Vitrectomy is a delicate procedure performed by ophthalmic surgeons in a hospital setting where there is access to an operating microscope. Removing the vitreous gel does not have a significant impact on the person’s visual function and acuity.
Who Should Undergo and Expected Results
Patients who qualify for vitrectomy include those with:
Vitreous haemorrhage - A condition characterised by the presence of blood in vitreous that causes blurred vision. It is typically due to diabetic retinopathy, vein occlusions, macular degeneration, or injury.
Advanced stage of macular pucker – A condition brought about by the growth of a transparent scar tissue over the retinal surface. Over time, the scar tissue shrinks and contracts, leading to impaired or lost vision.
Macular hole - A type of hole in the macula that can cause severe vision loss. Vitrectomy is performed to close the hole in retina by filling the cavity with air and gas so the patient can regain his or her normal vision. When left untreated, the condition can worsen overtime. There are three macular hole stages; foveal detachments, partial thickness holes, and full thickness holes. Patients with foveal detachments are more likely to achieve full macular hole recovery with treatment while those with full thickness macular hole generally have a poor prognosis.
Uveitis – A condition characterised by the inflammation of the interior part of the eye, triggered by an attack of the body’s own immune system. If left untreated, uveitis can lead to blindness.
Retinal detachment - Most cases of extreme retinal detachment are also treated with vitrectomy. This condition is often caused by viral and bacterial infections, as well as injury to the eye. However, those who see floaters and spots in their vision are typically not advised to undergo the surgical removal of the vitreous gel, especially if their condition is largely brought about by ageing.
Vitrectomy can also be performed during complex cataract surgery if the natural lens of the eye is dislocated and falls into the vitreous cavity. The procedure is performed to retrieve and remove the lens.
As for the expected results, vitrectomy has a high success and satisfaction rating, with most patients reporting significant vision improvement or restoration of sight. In general, the surgery is effective in restoring some vision lost due to retinal tear and traction retinal detachment and helps in the prevention of further detachment.
How is the Procedure Performed?
Patients are administered with anaesthesia before tiny incisions are made in the sclera (the white part of the eye) where several specialised tools are inserted while the surgeon receives guidance from a surgical microscope. A light pipe is also used to provide illumination inside the eye while the vitreous gel is removed using a vitrector, a special tool designed to reduce traction to avoid injury to the retina. Additional tools like forceps and scissors may also be used to remove the scar tissue on the surface of the retina, if present. After the vitreous gel is removed, an infusion port is inserted to replace the fluid in the vitreous with saline solution. This is done to maintain adequate pressure and keep the retina and other associated eye parts in place. In some cases, specialists use gas or air to replace the fluid inside the vitreous. In time, the fluid from the eye itself will fill out this space.
There are also instances when the vitreous needs to be filled out with silicone oil that is removed at a later date. Oil bubble is more likely to stay in place and would aid in faster recovery, especially among children who may not be able to keep their eye in proper position after surgery.
Full macular hole surgery recovery is typically achieved after a few months with most patients returning to their normal activity within a few weeks.
Possible Risks and Complications
Vitrectomy, just like other surgical procedures, carries some risks and possible complications, including the following:
Adverse reaction to the anaesthesia
Bleeding in the vitreous
Retinal detachment, which can lead to serious vision-related problems
Increased intraocular pressure for patients with glaucoma, leading to worsening eye condition
Endophthalmitis or infection inside the eye
Cataracts, which could form as a post-surgical complication of the procedure
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Sharma T, Virdi DS, Parikh S, et al. A case-control study of suprachoroidal hemorrhage during pars plana vitrectomy. Ophthalmic Surg Lasers. 1997 Aug. 28(8):640-4
Ghoraba HH, Zayed AI. Suprachoroidal hemorrhage as a complication of vitrectomy. Ophthalmic Surg Lasers. 2001 Jul-Aug. 32(4):281-8