In an anterior ischemic optic neuropathy (AION) is an acute occlusion of the artery that supplies the optic nerve. This eye condition is also known as an eye attack .
What is anterior ischemic optic neuropathy?
In anterior ischemic optic neuropathy, there is a circulatory disorder of the optic nerve head. The sudden decrease in blood flow to the optic nerve head causes a rapidly progressing deterioration in eyesight.
According to aviationopedia, anterior ischemic optic neuropathy (AION) is also known under the names opticomalacia , apoplexia papillae or eye infarction . This eye disease leads to a circulatory disorder of the optic nerve head. In most cases, this is caused by an acute occlusion or blockage of the ocular artery, which is located in the Zinn-Haller vascular ring and is responsible for supplying the optic nerve.
Due to the lack of blood circulation, the optic nerve head can no longer be adequately supplied with nutrients and oxygen. This in turn leads to the death of functional nerve tissue. Therefore, anterior ischemic optic neuropathy is considered an ophthalmic emergency.
The sudden decrease in blood flow to the optic nerve head causes a fastprogressive deterioration in eyesight. This is how they are nerve cellsOften irreversibly affected by the undersupply of the neural tissue. This effect can be compared to an ischemic stroke. Without a corresponding blindness possible. In this way, no new nerve cells are created from the dead neurons. treatmentthe patient is threatened with a considerable loss of vision. In the worst case, there is even one
The mean age for anterior ischemic optic neuropathy to develop is 61 years. In the case of non-inflammatory AION, around 19 percent of all patients also damage the neighboring eye. In the inflammatory form, there is a risk of damage to the neighboring eye after just a few days. In such cases, those affected are usually over 70 years old. A relapse in the same eye is rare.
Causes
In the context of anterior ischemic optic neuropathy, doctors differentiate between inflammatory and non-inflammatory AION. Most people have anterior ischemic optic neuropathy as a result of embolism . This is often caused by a pronounced inflammation of the inner skin of the heart ( endocarditis ) or by atrial fibrillation that has previously occurred. The resulting blood clot can move through the blood vessels to the Zinn-Haller vascular ring.
Once there, there is a considerable risk of clogging the supplying ocular artery. Another possible cause of anterior ischemic optic neuropathy is advanced hardening of the arteries ( arteriosclerosis ). This shows up primarily in people who suffer from diabetes ( diabetes mellitus ). On the other hand, inflammatory processes rarely lead to the development of the eye disease.
Other possible causes are generalized vasculitis (inflammation of the blood vessels) and temporal arteritis . Around 90 percent of all AION patients also suffer from cardiovascular diseases such as high blood pressure or diabetes. Farsightedness is a possible risk factor for AION . Occasionally, anterior ischemic optic neuropathy is also caused by surgery. Probable triggers in such cases are anemia and a drop in blood pressure.
Symptoms, ailments & signs
In most cases, the symptoms and symptoms of this disease appear very suddenly and unexpectedly. Those affected suffer from severe vision loss that occurs relatively suddenly. There is a myopia or a hyperopia , so that the patient in his daily life on a visual aid is reliant. In very serious cases, the disease can also lead to complete blindness .
This is no longer reversible and can no longer be treated. Furthermore, the eye no longer reacts or only reacts very slowly to incident light, so that the pupil hardly changes any more. However, these complaints do not affect the healthy eye. Both eyes do not necessarily have to be affected by the loss of vision; the symptoms often only occur in one eye. However, this still leads to severe restrictions in everyday life and restrictions in the field of vision.
The risk of a stroke or a heart attack is also significantly increased with this disease, so that the patients depend on regular examinations in their life. A loss of vision can also lead to severe psychological complaints or even depression .
Diagnosis & course
If anterior ischemic optic neuropathy is suspected, a doctor should be consulted immediately. After just a few hours, there is a risk of irreparable damage to the eyes. A thorough examination is carried out at the ophthalmologist’s office, which also includes an eye microscopic examination.
A possible indication of a parallel edema is an optic nerve head, which is abnormally fuzzy. In addition, the optic nerve head is often noticeable due to its paleness. This pallor is a criterion for poor blood flow. In addition, fine hemorrhages can be seen in the papillary region. Often there are restrictions of the visual field.
The doctor uses fluorescence angiography to determine the presence of decreased blood flow. If there is a suspicion of an inflammatory cause of AION, an arterial biopsy of the temporal artery is performed to examine the affected tissue. Investigations such as magnetic resonance imaging (MRI) of the head as well as an erythrocyte sedimentation reaction and the CRP procedure are also considered useful . Due to the underlying disease or risk factors, further examinations by a neurologist or internist are usually required.
Even with a quick start of medical treatment, the previous eyesight can usually no longer be restored. In the event of central retinal artery occlusion , therapy can only improve vision in one to eight percent of all those affected. In addition, AION patients have an increased risk of a heart attack or stroke . Around 18 percent of all affected people subsequently suffer from diabetic neuropathy .
Complications
Anterior ischemic optic neuropathy (AION), an embolism in the eye, can lead to severe impairment or even loss of vision in the affected eye as well as a restriction of the visual field due to the damage to the optic nerve. Because anterior ischemic optic neuropathy is an emergency, prompt diagnosis and treatment are critical.
The question of whether this is an inflammatory or non-inflammatory form also plays an important role in the likelihood of complications occurring. Causes of anterior ischemic optic neuropathy require adequate treatment. Treatment that has already caused damage to the eye cannot be reversed, but the occurrence of further damage can be reduced or avoided.
An AION that has been through, not treated or not treated in time also carries an increased risk of infarcts in larger organs such as the heart and brain. If the AION is not treated and sources of danger are not eliminated, further damage to the eye in question, including blindness and the occurrence of an AION in the other eye, can occur. Eliminating risk factors and avoiding triggering drugs can prevent or reduce the complications of anterior ischemic optic neuropathy.
When should you go to the doctor?
In principle, anterior ischemic optic neuropathy (AION) is an emergency situation that requires rapid care, if possible in an eye clinic. Alternatively, the treatment can also take place in a neurological or internal medicine clinic that has experience and equipment to locate and dissolve a blood clot (thrombus) in the vascular system of the head. The goal of rapid emergency care is to locate the causative thrombus in the optic nerve artery in order to dissolve it as quickly as possible.
The approximately one million extremely fine nerve fibers that leave the eye bundled through the papilla are very sensitive to a lack of oxygen supply. If professional care is not possible within hours, there is a risk of irreversible blindness in the affected eye. If the journey to the clinic takes a long time or if neither a specialist nor a clinic can be visited, the patient should be lying flat with the legs raised in order to improve the blood flow through the artery despite possible occlusion of the optic nerve artery (arteria opticus).
In addition, the eyeball can be lightly massaged, which in some cases led to the arterial blockade being lifted, so that at least a partial supply of the optic nerve head in the papilla was restored. If there is a kind of spontaneous healing during the transport to the clinic, because the blood supply to the optic nerve head has normalized again, it is important to visit the clinic anyway, because there is an increased risk of stroke and preventive measures should be initiated, which usually consist of drug anticoagulation exist.
Treatment & Therapy
An AION is usually treated in a clinic. So far, however, there is no uniform therapy scheme. Various methods are used, all of which are intended to improve blood circulation in the eye. These include massaging the eyeball, lying flat, giving infusions that thin the blood, and administering anticoagulant drugs such as acetylsalicylic acid and heparin .
It is also important to treat the underlying underlying diseases. As a rule, the patient is given drugs that stimulate blood circulation. These are mostly calcium channel blockers. If an inflammation is the cause of the AION, a high-dose cortisone treatment is carried out .
Outlook & forecast
The prospect of a cure in anterior ischemic optic neuropathy depends on the severity of the circulatory disorder. In mild cases and when the blood flow is interrupted for a short time, hardly any nerve cells in the optic nerve are damaged or destroyed. Therefore, there is no severe deterioration in eyesight. Often, a reduction in vision in everyday life can be compensated for or improved through the use of visual aids.
If the blood circulation is disrupted for a long time , damage occurs to the nerve cord that can no longer be repaired. The impairments remain permanent or can only be improved minimally with the available therapy options. Relief of the symptoms is possible in only about 40% of patients with anterior ischemic optic neuropathy. However, this moves to a minor extent. If the cardiovascular risk factors can be found and reduced, there is the possibility of improving eyesight in the healing process.
The other patients suffer lifelong impairments that cannot be remedied with current medical options. In addition to the prognosis of the underlying disease, there is an increased risk of suffering from a mental disorder due to the loss of eyesight. Therapy for mental health problems takes a long time. The prognosis prospects are individual for the mental impairments. The symptoms can continue unabated for years.
Prevention
Specific preventive measures against the AION are not known. It is recommended to prevent the underlying illnesses causing it.
Aftercare
With this disease, the options for follow-up care are relatively limited in most cases. The patient is primarily dependent on treatment by a doctor in order to completely alleviate the symptoms. If left untreated, the disease can, in the worst case, lead to complete blindness of the person affected.
The earlier the symptoms of the disease are recognized, the better the further course of the disease. Since the disease is still largely unexplored at the present time, no direct treatment can be carried out. The affected person is dependent on massages of the eye, which he can also do himself in his own home.
Medicines can also be used to thin the blood and thereby alleviate the symptoms. However, complete healing cannot be guaranteed. Those affected are primarily dependent on taking the medication regularly, although possible interactions with other medications must also be taken into account.
The administration of cortisone can also alleviate the symptoms. Often, the support of family and friends also has a very positive effect on the further course of the disease and can prevent psychological complaints.
You can do that yourself
AION is often caused by a disease of civilization such as arteriosclerosis, high blood pressure or diabetes mellitus. Since the yellow spot in the fundus of the eye continuously has the highest metabolic activity in the human body, cardiovascular diseases can often be recognized in the fundus – the underlying disease is also shown as an insufficient supply of the optic nerve in an AION.
It is therefore important that the underlying disease is carefully controlled, monitored and adjusted in order to keep the effects on the cardiovascular system as low as possible. Basically, if possible, prevention begins a few decades earlier with a healthy lifestyle, exercise and sport. Attempts should be made to keep the body in balance with as much healthy lifestyle as possible.
Ophthalmological checks should also be carried out. Even if the vision of the affected eye cannot be restored, it is still important to watch that eye and the other eye. Over time, the eye and brain will more or less learn to compensate for the loss of function in the affected eye.
If the visual acuity in the better eye is 30 percent due to other eye diseases, magnifying visual aids can help out. These are available for the near and far range. These aids are available on prescription from the ophthalmologist at the optician or specialized low-vision optician. The apartment can be designed to be rich in contrasts, including when setting the table or preparing meals or using the dishes.
This is where the area of activity of self-help associations such as DBSV or Pro Retina begins. In these associations, those affected with different eye diseases have come together to offer voluntary psychosocial advice and practical help in life – on an equal footing.
