Transverse septal cyst of the brain

Anomalous cerebral masses of a benign nature - congenital or acquired - include the cyst of the transparent septum of the brain.

In most cases, it is asymptomatic and is detected quite incidentally during visualization of brain structures. [1]

Epidemiology

There are no clinical data regarding the number of diagnosed transparent septal cysts, and septum pellucidum cavity cysts are detected in 0.04% of patients with cerebral cystic masses.

Causes of the transparent septal cysts in the brain.

The common causes of most cerebral cysts, including intracerebral cysts of the transparent septum, are most often congenital. That is, their formation is caused by abnormalities in the ontogenesis of the brain - the process of its formation by neural stem and glial cells - in the prenatal period (in the first two months of pregnancy).

Read also - Brain variants and anomalies

A transparent septal cyst of the brain in adults may be associated with a neuroinfection (meningitis), brain injury, tumor encephalopathy, or brain surgery.

More details in the publication - Complications and consequences after brain injury

Risk factors

Factors that increase the risk of abnormal formations in the form of brain cysts are generally considered to be:

• diseases of the pregnant woman (acute viral, chronic and systemic);
• teratogenic effects on the embryo and fetus of alcohol or drugs;
• various pregnancy pathologies, including nlacental insufficiency and fetal hypoxia;
• prematurity (birth earlier than 35-37 weeks of gestation);
• Complicated labor, often resulting in birth trauma;
• Cerebral edema in a newborn.

Pathogenesis

The transparent septum (septum pellucidum), located below the corpus callosum, is a triangular-shaped vertical membrane that separates the anterior horns (cornu frontale) of the left and right lateral ventricles (ventriculi laterales) located in the frontal lobes of the large hemispheres and forms their middle walls. This septum has two layers in the form of laminae consisting of white matter (substantia alba), nerve cells (neurons) and fibrin fibers.

A cyst (from the Greek "sac") is a delimited closed cavity with clear contours, often with fluid contents. The pathogenesis of congenital neuroepithelial cysts is not fully understood. Although among the hypotheses of the mechanism of transparent septal cyst formation there is a version of its connection with the functions of the ventricular (ventricular) system and the movement of cerebrospinal fluid - the cerebral aqueduct (aqueductus cerebri).

If the septum pellucidum cystic formation is filled with cerebrospinal fluid (liquor cerebrospinalis) produced by the lateral ventricles, a liquor cyst of the transparent septum is defined.

In addition, a cyst of the cavity of the transparent septum may be detected. A slit-shaped closed space, the cavity between the laminae of the transparent septum (cavum septum pellucidum), forms in the third month of fetal development and is considered a marker of the development of the nervous system. During the fifth month of the prenatal period, the laminae begin to fuse, and closure of the cavity is completed three to six months after birth.

But in 12-15% of cases, the cavity is not closed, especially in premature infants. And when found in adults, it is considered an anatomical variant of the norm

If cerebrospinal fluid remains in the closed cavum septum pellucidum, it is a transparent septal cyst in a child. [2]

Symptoms of the transparent septal cysts in the brain.

Often a cyst of this localization does not manifest itself in any way. But it can press on the brain tissue and cause symptoms such as headache accompanied by dizziness, vomiting and epileptic seizures, vision and hearing problems (patients often complain of tinnitus).

The first signs of a transparent septal cavity cyst are also manifested by recurrent headaches. In addition, patient complaints include dizziness, nausea and vomiting, visual disturbances. [3]

Complications and consequences

The consequences and complications associated with this cerebral cyst are due to its large size. It can put pressure on the occipital and temporal horns of the lateral ventricles of the brain and part of the aqueductus cerebri - with the development of obstructive hydrocephalus. In such cases, there are morning headaches in the frontal region, difficulty concentrating and other symptoms of increased intracranial pressure.

In addition, cyst compression can impair venous blood outflow from the brain or affect hypothalamic structures and midbrain regions, causing autonomic or sensorimotor symptoms.

Also does not exclude the rupture of cystic formation, fraught with quite serious CNS problems.

Diagnostics of the transparent septal cysts in the brain.

Symptoms and patient history are not sufficient for diagnosis. Instrumental diagnosis is necessary:

• echoencephaloscopy or neurosonography;
• color duplex ultrasound of brain structures;
• CT - brain CT scan;
• magnetic resonance imaging (MRI) of the brain.

Differential diagnosis

Differential diagnosis with arachnoid cyst of the interhemispheric gap, cyst of the pineal gland of the brain, arteriovenous malformation (aneurysm) of the vein of Galen is performed.

Treatment of the transparent septal cysts in the brain.

Only when a clear septal cyst is causing symptoms does it need to be treated.

Although there is no cure to get rid of this cystic formation,

Empirically prescribed drugs to improve metabolic processes in brain tissue - nootropics (Piracetam, Piriditol, Cerebrolysin).

Thus, Piracetam (Nootropil), used for memory impairment, cognitive decline and myoclonia, is taken at 1.24-4.8 mg per day (the dosage is determined by a doctor). At the same time, the side effects of this drug are manifested by nausea and vomiting, weight gain, nervousness and depression, hyperexcitability and hyperkinesias, insomnia or drowsiness

Diuretics - osmotic diuretics Diakarb (Acetazolamide), Mannitol - are prescribed for increased intracranial pressure. Diacarb tablets are taken 0.125-0.25 g twice a day, but it is contraindicated in liver and kidney failure, closed-angle glaucoma and children under 12 years of age. Side effects in the form of electrolyte imbalance in the body, thrombocytopenia, suicidal thoughts, growth retardation in children are possible.

Mannitol is administered intravenously (dose by body weight); its side effects include headache, nausea and vomiting, impaired circulation, dehydration and electrolyte imbalance.

If the cyst increases in size, surgical treatment may be required, which includes shunting the cyst cavity or endoscopic fenestration. [4]

Prevention

The possibilities to prevent the formation of congenital cysts of the transparent septum of the brain are limited by the fact that not all risk factors for the development of anomalies in the intrauterine period can be avoided. Therefore, prevention, in fact, concerns only the complete refusal of alcohol before and during pregnancy, as well as extreme caution in the use of medications.

Forecast

If symptomatic transparent septal cyst of the brain is treated and there are no neurologic complications, the prognosis is considered favorable.