Parinaud syndrome is vertical gaze paralysis. Paralysis of the eye muscles is caused by lesions of the midbrain and the nerve nuclei located there, as can be present from tumors, strokes, and inflammation. Treatment of the symptom complex depends on the triggering disease.
What is Parinaud syndrome?
In Parinaud syndrome, vertical gaze paralysis due to cranial nerve damage is present in combination with other neurologic symptoms. The symptom complex is also known as dorsal midbrain syndrome and was first described by Parinaud in the 19th century. Convergence movements of the eyes are limited in this phenomenon. Upward command movements can no longer be performed at all. Parinaud’s disease must be distinguished from Parinaud’s syndrome. This is an infectious disease caused by the bacterium Francisella tularensis. In the course of this disease, the so-called oculoglandular syndrome Parinaud can develop. This refers to conjunctivitis with swollen lymph nodes under the jaw and in front of the ear. This phenomenon occurs not only in the context of Parinaud’s disease, but also in the context of tuberculosis, fungal infections or syphilis.
Causes
Damage to the cranial nerves is the cause of vertical gaze paralysis in the form of Parinaud syndrome. More specifically, the cranial nerve nuclei are damaged. Most often, these are lesions in the midbrain area, that is, the brainstem between the pons and diencephalon. Most eye muscles are controlled from the midbrain. Usually, the causative lesion of Parinaud’s syndrome is located ventrocaudally of the tetrapod plate. A pineal tumor is most often responsible for lesions of this type. These tumors are tumors of the pineal gland and usually occur in childhood. A stroke in the midbrain area can also cause lesions near the four mound plate. In addition to these causes, other possible causes include inflammatory diseases of the brain, such as encephalitis or multiple sclerosis.
Symptoms, complaints, and signs
Parinaud syndrome is characterized primarily by upward gaze paralysis. Reflective movements in the paralyzed direction are possible as part of the doll head effect. The patients’ pupils are usually dilated and show no reflexes. A close-up view is no longer possible or only possible to a limited extent. Usually, the pupils are light-rigid, but other pupillary disorders may also occur. Convergence disorders of the bulbi are also present. In addition, nystagmus may develop, i.e. involuntary trembling of the eyes. Parallel eye movement does not necessarily have to be restricted in Parinaud syndrome. A uniform definition of the symptoms is difficult to give for Parinaud syndrome. The cause of the triggering midbrain lesion plays a role in the symptoms that actually occur. For example, with a tumor on the pineal gland, cerebrospinal fluid builds up and intracranial pressure increases.
Diagnosis and course of the disease
Symptoms are assessed by a neurologist in a pertinent manner, including testing of ocular motor function. After this initial assessment, an imaging procedure is usually ordered. This may be either a CT scan or an MRI. Cerebral pressure measurements supplement the imaging. The underlying disease behind Parinaud syndrome must be elucidated at diagnosis. Inflammatory diseases of the central nervous system can be detected by analysis of cerebrospinal fluid. Tumors such as the pineal tumor appear relatively typical on MRI and are accordingly easy to differentiate from inflammatory diseases. In addition, tumor markers are found in the cerebrospinal fluid for some tumor types. The prognosis varies in Parinaud syndrome depending on what caused the lesions in the midbrain.
Complications
As a result of Parinaud syndrome, affected individuals suffer from vision problems. The further course of this disease is very dependent on its cause, so a general prediction of complications is equally impossible. In many cases, however, treatment is no longer possible if the nerves have been irreversibly damaged. Patients are no longer able to see properly in a particular direction. As a rule, focusing on close objects is also no longer possible due to Parinaud’s syndrome, resulting in significant restrictions in the affected person’s everyday life.In many cases, Parinaud’s syndrome also results in significantly increased pressure in the brain. This often leads to severe headaches or unpleasant feelings of pressure in the head and ears. The treatment of Parinaud’s syndrome depends on the underlying disease, although it is not always positive. Without treatment, inflammation of the meninges can also occur, which can be fatal for the affected person. Possibly, Parinaud syndrome also reduces the patient’s life expectancy.
When should you see a doctor?
Parinaud syndrome is a rare condition that occurs in association with Parkinson’s disease, among other conditions. People suffering from a nervous system disorder should involve the doctor if the typical upward or downward gaze paralysis occurs. A reduced pupillary reflex as well as nystagmus are accompanying symptoms that need to be investigated. The same applies to a dilated pupil or unusual eye movements such as strabismus or exophoria. People suffering from multiple sclerosis, Parkinson’s disease, encephalitis or a neurological disorder are particularly at risk. Parinaud’s syndrome also occurs frequently in connection with a brain tumor or a cerebral infarction. People who notice the above symptoms and at the same time suffer from one of these diseases should immediately talk to the doctor in charge. Depending on the causative disease, either the neurologist, the general practitioner or an internist is responsible. Oncologists and psychologists may also be involved in treatment. Parinaud syndrome is treated depending on the cause and usually requires medication. Eye training as well as special glasses can support the therapy.
Treatment and therapy
Treatment of Parinaud syndrome depends on the causative disease. For example, a pineal tumor must be surgically removed. If CSF is accumulated as part of this disease, regulation of the increased intracranial pressure is first necessary. Before the operation, cerebrospinal fluid is drained for this purpose. The physician achieves this goal, for example, during an endoscopic ventriculocisternostomy, in which the third ventricle of the brain is opened at the base. Afterwards, the physician preferably performs microsurgical removal of the tumor, especially in the case of carcinomas, chorionic carcinomas and teratomas. The surrounding tissue must be spared as much as possible during this procedure. In the case of a malignant tumor, care must be taken not to spread tumor cells to other tissues during surgery. In the case of germinoma, there is no surgery, but primary radiation. In other malignant tumors, the head and spine are irradiated after microsurgical removal of the tumor to prevent metastasis through the cerebrospinal fluid. If the cause is inflammatory, the patient is usually given cortisone intravenously. If multiple sclerosis is suspected as the cause, acute treatment with cortisone is usually followed by long-term treatment with immunosuppressive drugs. In the case of meningitis caused by bacteria, antibiotics are administered instead of cortisone during the acute phase. Depending on the accompanying symptoms, treatment for Parinaud syndrome may vary.
Outlook and prognosis
The outlook and prognosis of Parinaud syndrome depend on the causative disease. A severe course results in bilateral damage to the eyes and eventual blindness. Severe courses are to be expected, for example, as a result of brain tumors, cerebral infarction or multiple sclerosis. The prognosis is better if Parinaud’s syndrome is caused by increased intracranial pressure. If this is treated early, recovery is likely. Aqueductal stenosis and encephalitis also offer a good prognosis if treated quickly. Life expectancy may be limited by Parinaud syndrome. Many patients die early from concomitant symptoms of the causative disease. Parinaud syndrome itself does not negatively affect life expectancy. However, the quality of life is limited by the impaired vision and the accompanying symptoms. The outlook and prognosis is determined by the specialist in charge. Usually an internist or neurologist is responsible. Parinaud syndrome itself is evaluated in the context of the underlying disease and the prognosis must be adjusted accordingly to the course of the disease. Vertical gaze paralysis can lead to accidents and falls in everyday life.As a rule, those affected are dependent on assistance and are also unable to carry out their occupation as before.
Prevention
Vaccines are available against some brain infections caused by infection. Strokes can be prevented by eating a healthy diet, getting enough exercise, and avoiding cigarettes and alcohol. Multiple sclerosis, on the other hand, cannot be prevented because the causes of this disease are still unclear. Midbrain tumors can also hardly be prevented.
Follow-up
In most cases, only limited and few measures of direct aftercare are available to those affected by Parinaud syndrome. Because it is a paralysis of the eyes that usually can no longer be fully treated, affected individuals are primarily dependent on early and rapid diagnosis of the disease. This is the only way to prevent further complications or other complaints. The earlier a doctor is contacted, the better the further course of the disease usually is. Affected persons are dependent on various interventions to remove the tumor, which is responsible for this disease. After such an operation, the patient should take it easy and rest. Exertion should be avoided. Regular checks and examinations by a doctor are also very important in order to detect further tumors at an early stage. When taking antibiotics, always ensure that they are taken regularly and in the correct dosage. These should also not be taken together with alcohol. In many cases, Parinaud syndrome reduces the life expectancy of the affected person.
What you can do yourself
Children and adolescents who have Parinaud syndrome usually suffer permanent damage. The extent of the visual impairment can be narrowed down by consulting a doctor immediately. After diagnosis, it is necessary to ensure that the eye can recover well. This is accomplished by wearing special glasses that correct the vision. In some patients, visual exercises, such as those used in the treatment of strabismus, help. Affected children should remain under parental observation to prevent accidents or falls. In the case of chronic symptoms, alterations must be made in the home. Since the child cannot see properly, stairs must be secured. In the case of mildly pronounced Parinaud’s syndrome, it is sufficient to help the child with everyday tasks during the first few months. After some time, activities such as riding a bike or climbing stairs can be done on their own. Parinaud syndrome does not require further treatment beyond that. The sufferer can lead a normal life with the necessary support, without the need for further therapeutic measures. However, if symptoms increase, the appropriate ophthalmologist must be consulted.
