Retinal venous occlusion

In some cases, circulatory disorders may lead to the occlusion of a retinal vein in the eye. Such occlusion results in congestion that may in turn lead to hemorrhages in the retina and the development of edema. Such changes may lead to irreversible damage of the photoreceptor cells. Depending on the blood vessel affected, the disorder is referred to as either a branch vein occlusion or a central vein occlusion.

In the case of a branch vein occlusion, the main complication is a swelling at the centre of the retina, the so-called “macula”. This may lead to impaired eyesight which patients experience as distorted or blurred vision. In some cases, severe circulation obstructions in the affected area of the retina may lead to neovascularization, which, if left untreated, may have effects ranging from vitreous hemorrhage to retinal detachment.

In the case of central vein occlusion, hemorrhages are spread out over the entire retina. In addition, swelling of the macula may occur. One serious complication is neovascularization, i.e. the growth of new vessels, which develops primarily in the area of the iris and the drainage area of the aqueous humour known as the “iridocorneal angle”. Such changes can lead to very high intraocular pressure.

Treatment is indispensable in cases of macular edema or severe ischemia, and neovascularization.

branch vein occlusion

Venenastverschluss

central vein occlusion

Zentralvenenverschluss

Treatment

  1. Intravitreal injection (IVI) of anti-angiogenic drugs: This form of treatment specifically inhibits metabolic factors in the retina and vascular tissue that promote neovascularization and edema. A variety of drugs are available. Compared to laser therapy, there is a higher probability of achieving improved vision upon completion. Frequent re-treatment can be necessary. The drugs are injected into the vitreous humour; the therapy is performed in the practice.
  2. Steroid depot therapy: In this form of therapy, a small cylinder (implant) is placed in the vitreous humour, which continually produces steroids for four months. Steroids have a very strong anti-inflammatory and edema-reducing effect on the retina. This operation has the advantage of making further therapy unnecessary for four months (unlike conventional intravitreal injections). The drawbacks are a significant rise in intraocular pressure in 10% of all patients and cataract development. This therapy usually needs to be performed in a hospital on an outpatient basis.
  1. Platzhalter (auf visibility:hidden gesetzt)
  2. Platzhalter
  3. Laser: In this procedure, low-intensity laser spots are placed around the centre of the retina. The laser increases edema removal at the retinal pigment epithelium and activates the body’s own immune system so that cells are recruited to the area in order to further reduce or completely eliminate the edema. As laser therapy is not as efficient as IVI or steroid depot treatment in improving vision, it is generally used for recalcitrant cases. Occasionally, re- treatment may be necessary in the event of residual swelling, In the case of neovascularization, laser therapy of the affected area of the retina is also the preferred therapy to improve oxygen consumption and oxygen requirements of the (central) retina.
  4. Surgery: In certain forms of retinal vascular occlusion, early surgery may improve eyesight, but only for select cases.