Optic disc edema
The papilla is the point in the eye where the optic nerve enters the eye. At this point there can be an accumulation of fluid, this is known as edema. A papilledema, therefore, a congestion in the optic nerve papilla. This “papillae” usually occurs due to increased pressure in the head. The result is deteriorated visual performance. Typically, papillary edema can be recognized by examination of the eye by swelling or bulging of the papilla.
What are the causes?
Optic disc edema can have various causes. Most of the time there are problems in the blood circulation, which leads to a build-up of fluid in the papilla of the eye. Depending on whether only one eye or both sides are affected, conclusions can be drawn about the different causes. If the papillary edema occurs on both sides at the same time, it is usually a matter of so-called central causes that have their origin in the skull (mostly in the brain). For example, increased intracranial pressure can lead to congestive papillae. But also inflammations in the brain (meningitis, encephalitis) or brain tumors can increase the pressure in the skull and thus cause a congestive papilla in both eyes. On the other hand, circulatory disorders such as central artery occlusion or central vein occlusion can also cause unilateral papillary edema.
Temporal arteritis (now officially called giant cell arteritis) is an inflammatory disease of the temporal artery. Inflammatory cells accumulate in the temporal artery (arteria temporalis). These can disrupt the blood flow in the temporal artery and thus disrupt the blood supply to the eye. As a result, blood flow to the affected eye deteriorates. Due to the changed blood flow situation, a congestive papilla (papillary edema) can develop. In addition, severe visual disturbances can occur. Temporal arteritis should be treated as quickly as possible, as long-term poor blood flow to the eye can cause permanent visual damage.
Read more on the subject at: Giant cell arteritis
Central artery occlusion
The central arteries are vessels that supply the retina of the eye. Since the eye itself is a closed area, the vessels of the eye, like the optic nerve at the papilla, have to get into and out of the eye. Optic disc edema usually leads to bulging of the optic nerve papilla. This not only has an influence on the eyesight, but also the blood flow situation of the vessels that reach the eye at the papilla is worsened. For example, papillary edema can disrupt the blood flow to the retina. In addition, the flow conditions change in a vessel that is compressed due to the papillary edema. A small blood clot (thrombus) can quickly develop in the affected area, which then completely closes the artery (central artery occlusion). As a result, the retina of the affected eye is no longer adequately supplied with blood, causing damage to the retina and the resulting (sometimes irretrievable) visual disturbances.
How is papillary edema diagnosed?
The ophthalmologist can diagnose disc edema in a number of ways. Typically, the first step is an anamnesis in which the person concerned expresses the corresponding complaints (visual disturbance, headache). A so-called ophthalmoscopy is then performed. The fundus (including retina and papilla) can be viewed enlarged with a special ophthalmoscope. A congestive papilla can be diagnosed in such an examination.
Imaging methods are also suitable for diagnosis. For example, an ultrasound of the eyeball can be done. However, sectional imaging methods such as CT or MRT are in principle also suitable for diagnosing papillary edema.
MRI of the eye
Magnetic resonance tomography is a sectional imaging method. The MRI of the eye specifically examines the eye region so that a three-dimensional image of the eye can be reconstructed afterwards. This means that even small changes in the eye can be detected. MRT is particularly well suited as an imaging method for the eye, since this examination allows the various types of soft tissue in the eye to be clearly distinguished. Therefore, one can see in an MRI whether the papilla of the examined eye is swollen. In addition, a change in the consistency can also be perceived in the MRI when liquid is deposited. Typically, the pupillary edema in the MRI is shown in a different level of brightness than the surrounding tissue.
Unilateral versus bilateral optic disc edema
In principle, papilledema can occur either in both eyes at the same time or in only one eye.
If bilateral papillary edema occurs, the disease is mostly due to central causes. For example, increased intracranial pressure can lead to congestive papillae. This creates increased pressure within the skull due to various diseases. Because of the hard skull bone, this pressure can only escape in a few places. A typical place for this are the papillae in the eye, here the entrance of the optic nerve is literally pressed into the eye socket by the pressure in the skull. Depending on the level of intracranial pressure, papillary edema can be stronger or weaker. Possible reasons for increased intracranial pressure that causes pupillary edema on both sides are trauma to the skull, brain tumors or even inflammation of the brain and / or meninges.
If, on the other hand, there is only one-sided pupillary edema, the blood flow to the affected side is usually disturbed. This can be for many different reasons. Diseases such as high blood pressure, diabetes mellitus (blood sugar disorder) or inflammatory changes in the vessels (such as temporal arteritis) are possible causes of impaired blood flow. As a result, pupillary edema can be triggered. Typically, the symptoms of these underlying diseases initially only appear in one eye. Usually, however, the second eye is also affected a little later, as the vessels in both eyes are affected by these underlying diseases. Consistent therapy of the risk factors (diabetes therapy, lowering of blood pressure, etc.) can, however, prevent disease in the second eye and alleviate the symptoms in the affected eye.
With optic disc edema, there are usually two accompanying symptoms. Vision is disturbed by the swelling of the papilla and thus also of the optic nerve. Affected people typically complain that their vision is only blurred in the affected eye. In addition, headaches are often associated with papillary edema. The reason for this is the increased intracranial pressure, which is usually the cause, which also triggers the headache.
Visual disturbances can be triggered by papillary edema. Due to the expansion of the tissue at the site of the papilla due to the accumulation of fluid, the surrounding tissue and thus the retina can also be influenced. If there are slight changes in shape such as fluid accumulation around the papilla, the retina is displaced. This can lead to a distorted perception of images.
Other important structures of the visual apparatus can also be damaged. If, for example, the receptors and nerve cells are affected, which transmit important information about the light that falls into the eye to the brain, blindness can even result from the papillary edema. It may also be that only individual parts of the visual field are affected by the visual disturbances caused by the papillary edema.
We speak of increased intracranial pressure when the pressure in the skull itself is increased. This can result from swelling of the brain, but the chambers in which the cerebrospinal fluid (liquor) is produced are often also involved in the development of high intracranial pressure. The growth of tissue, for example through a tumor, can also increase the pressure inside the skull and thus lead to intracranial pressure. Since the head is almost completely closed off by the skull, the pressure can only escape the head in a few places. One of these places is where the optic nerve passes through the skull and into the eye socket. Increased intracranial pressure can push additional tissue or the optic nerve through this gap, which can cause papillary edema.
Read more on the subject at: Increased intracranial pressure
How is papilledema treated?
The treatment of papillary edema is very dependent on the cause of the disease.
Circulatory disorders can often be attributed to increased blood pressure throughout the body. Therapy therefore consists of reducing blood pressure so that the treatment takes place throughout the body and not directly on the eye.
If, on the other hand, the papillary edema occurs as a result of a rheumatic-inflammatory disease of the vessels, a treatment is sought which treats the underlying rheumatic disease process. This often requires drugs that downregulate the body's immune system.
If there are causes inside the skull that increase intracranial pressure and thus cause papilledema, the underlying disease must also be treated. For example, brain edema can be treated with medication.
If the body builds up too much brain water so that it builds up, a small tube (so-called liquor drainage) can be inserted, which drains the brain water and thus lowers the pressure.
If the cause of the papillary edema lies in the eye itself, drug therapies can also be used. But surgical therapies are also possible, depending on the exact underlying cause.
How long does papillary edema last?
How long papillary edema lasts depends very much on the underlying disease. Many causes, such as increased intracranial pressure, can in some cases be treated quickly. After successful treatment, the papillary edema disappears very quickly on its own. Other causes (e.g. increased blood pressure) are chronic diseases that can be adjusted and improved with medication. However, they cannot be completely treated, so that the risk of developing pupillary edema remains.