Indirect ocular trauma is damage or injury to the retina that did not occur directly. Possible causes of such trauma include fat emboli or facial skull fractures.
What is indirect ocular trauma?
In indirect ocular trauma, there is damage to the retina. However, this damage did not occur because of direct trauma. Thus, there has been no direct force on the orbit prior to the onset of symptoms. Indirect ocular trauma is usually caused by circulatory disturbances resulting from trauma to other areas of the body. Symptoms of trauma may appear immediately or with a delay of several days. Therapy is usually conservative. In the majority of cases, the resulting damage regresses. However, this regression process may take several weeks. In some patients, visual disturbances or visual field loss persist permanently.
Causes
Indirect ocular trauma is called indirect because it occurs without direct force to the eye socket (orbit). The trauma develops at the base of a more distant violent impact. Accordingly, the cause is injuries that may not even be close to the eye. These injuries affect and damage the retina through various pathways. The exact pathogenesis of indirect ocular trauma can vary widely. Fracture of a long bone may result in injury to the fatty marrow. This may release fat droplets from the marrow and wash them into the blood. This process is also known as fat embolism. The fat particles are transported further via the bloodstream and are deposited in the body. Most commonly, the fat particles become lodged in the lungs, where they cause fat embolism. However, depending on their size, they can pass through the pulmonary vessels and only get stuck in the smallest vessels of the retina. There they deposit and cause an embolism. The small capillaries of the retina are blocked. The blood can therefore no longer circulate and the tissue behind the occlusion is no longer supplied with oxygen and nutrients. As a result, it dies. Another cause of indirect ocular trauma is an injury to the chest (thorax). When an embolism occurs, there is an increase in pressure in the chest. This increase in pressure also affects the vessels. The pressure travels in a wave throughout the vessels of the body. When it reaches the small vessels of the eye, rupture or spasm may occur. The result is an acute undersupply of the retina. This undersupply due to lack of blood flow is called ischemia. Car accidents can also result in indirect ocular trauma. In particular, chest compression from a seat belt can cause damage to the eye. A particular form of indirect ocular trauma is high-altitude retinopathy. In cases of severe fluid loss or at very high altitudes, the hematocrit and hemoglobin concentrations in the blood are elevated. The elevation of these two blood components increases blood viscosity, allowing small vessels, such as retinal vessels, to become blocked.
Symptoms, complaints, and signs
Indirect ocular trauma can cause a wide range of symptoms and complaints. The first signs of trauma generally do not appear until several days after the triggering event. Typically, mild to moderate visual disturbances present after three to five days and become more severe in the following days. Affected individuals often experience a loss of visual acuity. This is a disorder that results in rigid visual acuity. As a result, the eye can no longer adjust to different visual situations, which leads to significant limitations in everyday life. If indirect ocular trauma is treated early, visual loss can often be averted. However, further complaints of the eyes usually occur, for example pain or discomfort. In extreme cases, complete blindness occurs. The visual disturbances are irreversible and often precede mental complaints. Young people often suffer from psychological upsets as a result of indirect ocular trauma, which can develop into full-blown depression in the course of time.Outward signs of trauma include visible injuries, bruising, or skin changes, depending on the cause and extent of the indirect ocular trauma.
Diagnosis and course of the disease
In cases of visual disturbances, a detailed history should be taken first. In particular, accidents or injuries that occurred only a short time ago should be noted in the history. If indirect ocular trauma is suspected, fundus diagnostics are performed. This involves examining the back of the eye with an ophthalmoscope. With the help of a magnifying glass, the attending physician looks through the pupil into the interior of the eye. At the same time, the eye is illuminated with a light source. During ophthalmoscopy, bleeding within the retina becomes visible. A typical examination finding is a so-called cotton-wool foci. These are cotton-wool-like shadows in the area of the retina. These are white or yellowish in color. These cotton-wool foci are caused by swelling of the nerve fibers in the fibrous layer of the retina (stratum neurofibrarum). They occur because ischemia also impairs neuroaxonal transport.
Complications
Various symptoms or complications may occur with this trauma. These usually depend on the cause of the trauma, so a definite course of the disease cannot be predicted. In most cases, however, this results in complaints of the eyes. Patients usually suffer from visual disturbances or pain in the eye. In the worst case, those affected suffer complete blindness, which can no longer be treated and is therefore irreversible. In many cases, sharp vision is no longer possible for the patient. Likewise, veil vision or so-called double images occur. The quality of life of the affected person is significantly reduced by this trauma. Young people in particular suffer from depression or other psychological upsets due to visual complaints. However, life expectancy is usually not reduced by this trauma. It is not uncommon for the trauma to cause further facial deficits, which can complicate the daily life of the affected person. The treatment itself does not lead to further complications. However, most of the damage cannot be restored, so the patient may be dependent on visual aids.
When should you see a doctor?
If there is evidence of a circulatory disorder, a doctor should be consulted. If there is dysfunction in the area of the head, there is cause for concern. A physician should be consulted as soon as disturbances in vision, headaches, or a feeling of pressure in the eye develop. Changes in visual acuity, a flickering in front of the eye, problems with sharp vision or signs of fatigue of the eye, should be examined and treated. If the changes occur immediately after the eye has been exposed to violence, a check-up is recommended as soon as possible. After an accident or an act of violence, a doctor is needed as soon as there has been any forceful impact on the area of the eye or face. Discoloration of the eye, bleeding of the eye or deformation of the eye socket should be examined by a specialist. If failures of the facial muscles or nerves develop, a visit to the doctor should be made. To minimize permanent damage to vision or blood vessels, it is advisable to consult a doctor or go to a hospital immediately after the damage. If there is unusual secretion from the eye, this is a warning sign from the organism of existing injuries and damage. If there are feelings of pressure in the chest, problems with breathing or a general feeling of malaise, a doctor is also needed. If there is anxiety, pain or lung problems, a physician should be consulted.
Treatment and therapy
Usually, findings in the fundus area resolve on their own within four to six weeks. In some cases, vision loss or visual field loss remains. If visual disturbances persist, therapy with high-dose steroids or prostaglandin inhibitors may be attempted. In high-altitude retinopathy, normalization of hemoglobin and hematocrit levels is the primary goal. For this purpose, patients are administered isovolemic hemodilutions. The drugs pentoxifylline and aspion are also resorted to.
Outlook and prognosis
The prospect of suffering indirect ocular trauma increases in an accident involving a thoracic injury, fracture of a long tubular bone, or fat embolism precipitated by such incidents. In these cases, indirect trauma to the retina must be considered in the presence of subsequent visual disturbances. Treatment must be aimed at ensuring that no subsequent damage remains to the eye. The chances of this are quite good. Since indirect ocular trauma is not due to a direct impact on the ocular environment, the associated damage to the retina often occurs with a delay due to a causative agent that was actually effective elsewhere. The precipitating causes of this event require treatment first. However, the prognosis for indirect ocular trauma is quite good because the resulting sequelae are readily treatable with conservative therapy. Indirect ocular trauma can sometimes be caused by causative agents so far removed from the eye that a connection must first be established. In most cases, the consequences of indirect ocular trauma can resolve within several weeks. Only in a part of the affected persons permanent damages of the eye remain. These can remain, for example, as visual field defects or visual disturbances. Whether these can still be improved with medication or at least their effects mitigated must be decided on a case-by-case basis.
Prevention
High-altitude retinopathy can be prevented by good preparation for being at high altitude. Adequate ascent and descent stages should be followed. This will ensure that the body can acclimate to the varying air conditions. The normal form of indirect ocular trauma is difficult to prevent. However, if visual disturbances occur after an accident, an ophthalmologist should be consulted as soon as possible.
Aftercare
Indirect ocular trauma requires timely treatment and targeted follow-up care. This includes, among other things, prevention. For example, depending on the situation, individuals can prepare for higher altitudes by preparing properly. In this way, they reduce the risk of altitude retinopathy. Reducing the pace of ascent and descent is also helpful in acclimating the body. However, there are few options for prophylaxis in the classic form of the disease. In connection with an accident, those affected should immediately consult an ophthalmologist in case of visual disturbances. The disturbance of the normal visual function has an extremely disturbing effect on the patients. Nevertheless, they should remain as calm as possible and not panic. Stress could have negative consequences on the condition and worsen the chances of recovery. That is why it is important for those affected to take the necessary rest. At home or in a familiar environment, they can avoid major difficulties. This also means increased protection of the eyes from external influences. Direct sunlight, strong winds and large temperature fluctuations should be avoided, as should prolonged gazing at a computer screen. Those affected should also avoid contact with cosmetics and even water to prevent irritation.
What you can do yourself
Indirect ocular trauma is usually accompanied by impairment of usual visual function and is therefore very distressing for those affected. Nevertheless, it is important to remain calm and avoid stress if possible, as this may have a negative effect on the state of health as well as the prospects for recovery. At best, patients allow themselves sufficient rest and spend a lot of time at home or in familiar surroundings to avoid difficulties. It is particularly important to protect the eyes from strong external influences, such as wind, sunlight, cold and heat. In addition, it is not advisable to spend hours in front of various screens every day, as this costs the eyes considerable effort. Contact with water and cosmetics should also be avoided so that irritation of the eye does not develop and the disease regresses. In this context, attention should also be paid to meticulous hygiene in the area of the diseased eye, because contamination sometimes has serious consequences for the further course of the disease. Patience is therefore required from patients with indirect ocular trauma.In certain situations, it is advisable to seek assistance from others to avoid mistakes or accidents caused by impaired vision.
