A parietal foramen is an opening at the upper edge of the so-called parietal bone on the skull. Through it passes the emissary parietal vein, which is a connection to the superior sagittal sinus, as well as a collateral branch of the occipital artery. However, the presence and size of such foramina varies from person to person. While in some there is no parietal foramen at all, abnormal enlargement of the same occurs in the context of congenital parietal foramen permagnum disease.
What is foramen parietale permagnum?
Foramen parietale permagnum is a rare congenital skull bone defect based on a gene mutation. This is usually located on either side of the parietal ossa approximately one centimeter lateral to the sagittal sutura and above the lambdoid sutura. The main visual feature is a significant enlargement of normal parietal foramina, which are physiologically present in approximately 65 percent of the population. Thus, a parietal foramen permagnum can range in size from at least five millimeters to several centimeters. The prevalence is approximately 1 in 15,000 to 1 in 25,000.
Causes
In this case, the dysplasia of the skull bone is genetic and due to certain gene mutations. However, the basic defect of the local ossification disorder is still unknown. It is known, however, that the mode of inheritance is autosomal dominant. Foramina Parietalia Permagna can be classified into different groups depending on which mutation in which gene underlies the respective case. If there is a mutation in the MSX2 gene at gene locus 5q35.2, this foramen belongs to group 1, whereas if there is a mutation in the ALX4 gene at 11p11.2 5q35.2, this oversized foramen is assigned to class 2. In addition, there is a third group in which no specific mutation has yet been found at a particular gene locus. A parietal permagnum foramen per se has basically no disease value worth mentioning. However, it often occurs associated with a more complex syndrome, such as Saethre-Chotzen syndrome also called acrocephalosyndactyly type 3](ACPS 3).
Symptoms, complaints, and signs
A parietal permagnum foramen is characterized by an oval or roundish opening in the parietal bones, approximately five centimeters in size in adulthood, which can be either unilateral or bilateral and is closed membranously. Very commonly, a mongoloid eyelid axial position is found. Occasionally, headache and/or absences occur, but these are very nonspecific symptoms. Frequently, the large foramina are associated with cleft lip and palate. Abnormalities on the scalp or local alopecia may also occur. In the course of studies it has been noticed that in a clan with three consecutive affected generations a foramen parietale permagnum occurs in combination with ptosis, i.e. partial or complete drooping of one eyelid. In addition, other cranial bones may be involved in some circumstances, for example, a cranium bifidum. In particular, the most common complications include severe headaches that can affect quality of life. Taken alone, however, foramina parietalia permagna have basically no clinical significance. This occurs only when they are accompanied by syndromes. Possible syndromes include FG syndrome, Potocki-Shaffer syndrome, Ritscher-Schinzel syndrome, multiple cartilaginous exostoses, and Toriello syndrome.
Diagnosis
Thanks to today’s modern examination methods, FPPs can be diagnosed very early in the unborn child during gestation. However, sometimes they are incidental findings in adulthood. During a clinical examination, the openings are often palpable as a flattened region or as an enlarged posterior fontanel. The openings are well visible in an anterior-posterior radiograph. In a lateral radiographic image, however, it is often more difficult to detect a parietal permagnum foramen. CT imaging with 3D reconstruction can delineate the osseous defect very accurately, and magnetic resonance (MR) imaging can visualize any intracranial changes. If FPP is concomitant with vascular abnormalities, additional vascular imaging is helpful.Prenatal diagnosis during pregnancy is recommended in families with a known genetic defect that may be associated with foramina permagna. This prenatal diagnosis is performed between the 18th and 20th week of pregnancy and includes neurosonography in the context of further ultrasound diagnostics, as well as molecular genetic diagnostics for the MSX2 and ALX4 genes. The disease course is usually asymptomatic and benign, but spontaneous closure is extremely unlikely.
Complications
Foramen parietale permagnum does not cause specific symptoms or discomfort in most cases. For this reason, the diagnosis of foramen parietale permagnum also occurs relatively late, making early treatment impossible. Those affected suffer from headaches, which, however, occur only sporadically and are not permanent. Likewise, confusion may occur, although this is also not permanent. It is not uncommon for patients to also suffer from a cleft palate, which significantly reduces the quality of life. One of the two eyelids hangs downwards. Due to the headaches, it is not uncommon for depression or other psychological upsets to occur. It is not uncommon for those affected to also suffer from fatigue or irritability and no longer take an active part in life. As a rule, the affected person is also restricted in his or her everyday life by the Foramen Parietale Permagnum, so that certain dangerous sports should not be performed. Furthermore, the disease can be treated by surgical intervention. In this case, no complications occur and there is no reduction in life expectancy.
When should one go to the doctor?
A doctor should be consulted for foramen parietale permagnum. This complaint can cause significant limitations in everyday life. Especially in children, early treatment is necessary to prevent developmental disorders. The doctor should be consulted if there is an opening at the parietal bone. Severe headaches or a malposition of the head may also indicate the parietal foramen permagnum and should be examined. In some cases, the affected person also suffers from a cleft palate, although this is recognized and treated at birth. In most cases, the Foramen Parietale Permagnum only causes pain in the head or neck. If this pain significantly limits everyday life and reduces the quality of life of the affected person, a visit to the doctor is recommended. The treatment of the disease is carried out by a general practitioner or an orthopedist. In most cases, this can alleviate the symptoms. In the case of parietal foramen permagnum, however, the affected person should refrain from dangerous sports or activities in which there is an increased risk of accidents. In most cases, there is a positive course of the disease.
Treatment and therapy
Treatment for an enlarged foramen parietale is mostly conservative. Persistent cranium bifidum, however, warrants surgical intervention for closure. Possible associated headaches and seizures can be treated with medication. The risk for penetrating brain injury, although low, may cause anxiety in patients and relatives, so good eduction about the abnormality of the skull is very important. Thus, parents, affected children and even teachers should be well informed about the condition. This way they can avoid risky behaviors that could lead to such an injury, such as contact sports, if possible. Cranioplasty is considered only for risk groups for skull injury, such as active children, but the use of such a procedure remains controversial.
Outlook and prognosis
The disease is based on a genetic defect. Because of legal requirements, human genetics cannot be altered. For this reason, symptomatic treatment takes place. The prognosis of foramen parietale permagnum is tied to the extent of existing symptoms. Complete freedom from symptoms is not to be expected. If the irregularities such as headaches or cramps occur sporadically and not very strongly in the patient, a medicinal therapy is applied.As soon as the impairments become apparent in the course of life, the active ingredients in the remedies alleviate the existing complaints until recovery occurs after some time. These patients report periods of complete recovery and periods when an increase in symptoms is observed. Often the developments depend on the lifestyle and the developments in the immediate environment of the affected person. In severe cases, surgical intervention is performed. In this the skullcap is closed. Operations are always associated with various risks and side effects. If complications occur, the prognosis for the patient worsens. If the operation is successful, there is a rapid improvement in general health. Headaches or seizure disorders subside. Nevertheless, some restrictions are necessary during the course of life. Because there is an increased risk of injury, the skullcap must be protected from foreign impact.
Prevention
The most important measure to prevent complications is adequate eduction of the affected person and his or her environment. High-risk sports involving a lot of physical activity or other dangerous behaviors should be avoided as much as possible. If the skull bone defect is already diagnosed prenatally, the further procedure must be planned and discussed with the pregnant woman. For example, an elective cesarean section reduces the risk of traumatic injury to the brain during the birth process.
Follow-up care
In most cases of foramen parietale permagnum, there are no options for follow-up care. However, these are not really necessary, since the condition can be treated completely and without complications by surgical intervention. After the treatment, the symptoms disappear completely. The earlier Foramen Parietale Permagnum is detected, the more successful is the further course of this disease in most cases. Therefore, a doctor should be consulted at the first symptoms that indicate the disease. In most cases of Foramen Parietale Permagnum, a surgical procedure is performed on the skull to completely relieve the symptoms. Since this is a relatively serious and complicated procedure, the patient should definitely rest afterwards and not exert his body unnecessarily. Bed rest should be observed, and stressful activities should also be avoided. In the case of children, information should be provided by the parents prior to the procedure to avoid unnecessary feelings of anxiety or other psychological upsets. Also, care and support in everyday life by one’s family or friends is always helpful and usually accelerates healing. Successful treatment of foramen parietale permagnum also does not reduce the patient’s life expectancy.
What you can do yourself
To improve the quality of life, the patient should avoid anything that could trigger headaches or discomfort of the skull. Stress should be reduced and likewise physical overexertion should be refrained from. Hectic and hurry often lead to inner tension, which have a negative influence on the organism. Musings and arguments should be avoided, so that no internal pressure builds up. As soon as the first headaches appear, it is important to rest and take it easy. Sufficient sleep, adequate fluid intake and avoidance of loud ambient noises help to alleviate the symptoms. When dealing with the visual abnormalities of the disease, a strong sense of self is important. The use of accessories to cover up or cosmetic tricks can be applied. In most cases, an open approach to the disease leads to acceptance by people in the immediate social environment, so that the use of accessories can increasingly be dispensed with. In addition, conversations with therapists, relatives or other sufferers help to get to know the perception of the environment. Often, this leads to cognitive changes and transformations in one’s own attitude, as many worries are shown to be unnecessary. The exchange with other people additionally contributes to the reduction of fears.
