Vitrectomy is a major operation

Pars plana vitrectomy

Vitreous Surgery (PPV)

For some diseases inside the eye, a vitreous body removal (pars plana vitrectomy, PPV) is necessary. This procedure can be carried out without any further measures, but it can also be combined with other treatments of the retina. The empty vitreous space must be filled with a substitute substance (liquid, oil, gas) in order to maintain stability.

What is the vitreous?

The vitreous is a transparent, gel-like mass inside the eye. The vitreous space takes up about 2/3 of the volume of the entire eye and is bounded by the retina, the lens and their suspension apparatus. The vitreous body consists almost entirely of water, which still contains binding substances (hyaluronic acid, collagen). The glass body adheres firmly to the surrounding structures in several places. It usually sits loosely on the retina, but it can also form very tight connections.

For which diseases is a vitrectomy (removal of the vitreous humor) performed?

Several eye diseases can cause the vitreous body to be surgically removed. These are diseases of the retina or the vitreous itself. The operation can be useful for bleeding into the vitreous space that does not resolve by itself, for dangerous inflammations within the eye (endophthalmitis), for long-term disturbing vitreous opacities and foreign bodies in the eye. Sometimes an operation also has to be performed because the lens has moved back into the vitreous humor.

On the retina, the cell layer that absorbs the incident light, various other clinical pictures can make it necessary to remove the vitreous humor. These include retinal detachments as well as damaging membranes on the retina caused by other eye diseases. The latter can form after stimuli such as damage to the retina due to diabetes (diabetic retinopathy), injuries or retinal tears.

Preliminary examinations that are necessary before a vitreous surgery

The anamnesis (interview and questioning of the patient) often already gives clues about the disease at hand. The basic ophthalmological examination is carried out, which includes, among other things, an eye test, examination of the eye with assessment of the fundus when the pupil is dilated and eye pressure measurement. An ultrasound examination is carried out in particular if (e.g. due to vitreous hemorrhage) the view is reduced or absent. The particular disease may require further examinations. If an artificial eye lens is to be used, the eye must be measured using special methods (biometrics). If the patient takes anticoagulants such as Aspirin® or Marcumar®, these should usually be discontinued before the operation. This must be discussed with the medical team.

The operation to remove the vitreous humor (pars plana vitrectomy)

The surgical removal of the vitreous (pars plana vitrectomy, PPV) is carried out under general or local anesthesia through a syringe next to the eyeball (retrobulbar anesthesia).

The procedure is carried out under the surgical microscope. Instruments are inserted through three small punctures in the anterior lateral eyeball area (light source, infusion cannula and the actual suction-cutting device for removing the vitreous body). With the suction and cutting device (vitrectome), the vitreous body is gradually carefully cut out and sucked out, while a liquid solution is filled through the cannula in order to maintain normal pressure in the eye. The glass body and any membranes that may be present are removed as completely as possible.

Depending on the disease, further measures can then be taken. So z. B. a laser treatment of the retina can be carried out as part of the operation. In many cases it is advisable to remove the eye lens during a vitreous operation and replace it with an artificial lens.

After removing the vitreous or other actions, the room must be refilled. Often it is sufficient to introduce liquid (Ringer's solution). In some cases gas is useful, e.g. B. with a retinal detachment in the upper area of ​​the eyeball. The effect of silicone oil is that pressure is exerted on the entire retina in order to fix it on the layers below. The puncture holes are finally provided with sutures and the eye is provided with a bandage. The gas and liquid solution are slowly replaced by the body's own fluid after the operation. Silicone oil, on the other hand, has to be drained off later in a follow-up procedure and replaced with liquid.

What complications can arise during a vitrectomy (removal of the vitreous humor)?

Bleeding and secondary bleeding are possible. Infections can be very serious. The retina as well as other structures of the eye or the surrounding area can be injured. In particular, if the eye is filled with oil, the lens can become cloudy, the intraocular pressure increased or the cornea cloudy. In a few cases, blindness or even loss of the eye can occur.

How should the patient behave after the operation?

The day after the operation, the ophthalmologist will examine you with an eye test and eye pressure measurement. The newly operated eye should be spared at first. The patient should avoid physical exertion. Swimming and the application of make-up should also be avoided. Eye drops, as well as other medications, should be used by the patient as directed by the doctor. Sometimes it is important to keep your head in a certain position after the operation. The doctor will tell the patient about this.

Chances of success of the vitrectomy

The prognosis after vitreous removal depends primarily on the original disease. Vitreous hemorrhage can be removed without any problems, but there is a risk of further bleeding. If there is inflammation within the eye (endophthalmitis), removal of the vitreous humor can in many cases bring an improvement. Vitreous opacities can usually be removed without problems, although it is worth considering whether it makes more sense to leave them in place. In the case of foreign bodies, the prognosis depends on the severity of the injury and the accompanying symptoms such as infections. Retinal membranes are usually relatively easy to remove, but quite often develop again. Retinal detachment can be treated well with a vitrectomy; the prognosis here also depends on how far the disease has progressed.