Third ventricle(ventriculus tertius) looks like a vertical slit (Fig. 3.22; see Atl.).
1 – caudate nucleus;
2 – columns of the vault;
3 – pineal gland;
4 – upper and
5 – inferior colliculus;
6 – fibers of the middle cerebellar peduncle;
7 – pathway of the superior cerebellar peduncle (prepared);
8 – tent core;
9 – worm;
10 – spherical,
11 – corky and
13 – dentate nucleus;
12 – cerebellar cortex;
14 – superior cerebellar peduncle;
15 – leash triangle;
16 – thalamic cushion;
17 – visual thalamus;
18 – posterior commissure;
19 – third ventricle
;
20 – anterior nucleus of the visual thalamus.
His side walls formed by the medial surfaces of the thalamus and hypothalamus. The latter limits the ventricle and below. Its back wall includes posterior commissure, under which there is a water supply hole. The anterior wall of the ventricle is formed columns (pillars) of the vault and passing in front of them anterior commissure, related to telencephalon. Between the columns of the fornix and the visual tuberosities are located interventricular foramina, connecting the cavity of the third ventricle with the lateral ventricles cerebral hemispheres. The superior wall of the third ventricle consists of an epithelial lamina (a remnant of the wall of the medullary bladder) and choroid, forming choroid plexus third ventricle.
The human brain is a complex and amazing structure, all the mysteries of which scientists have not yet unraveled. One of the most interesting mechanisms of functioning nervous system What remains is the process of formation and circulation of cerebrospinal fluid (CSF), which is carried out using the 3rd ventricle of the brain.
3rd ventricle of the brain: anatomy and physiology
The third ventricle of the brain is a thin slit-like cavity, bounded by the visual tuberosities of the thalamus and located in diencephalon. Inside, the third ventricle of the brain is lined with a soft membrane, a branched choroid plexus and filled with cerebrospinal fluid.
Physiological significance 3 ventricles are very large. It ensures unimpeded flow of cerebrospinal fluid from the lateral ventricles into the subarachnoid space for washing the brain and spinal cord. Simply put, it ensures the circulation of cerebrospinal fluid, which is necessary for:
- regulation of intracranial pressure;
- mechanical protection of the brain from damage and injury;
- transport of substances from the brain to spinal cord and vice versa;
- protecting the brain from infection.
3rd ventricle of the brain: normal in children and adults
A normally functioning liquor system is an uninterrupted and harmonious process. But if even a small “breakdown” occurs in the processes of formation and circulation of cerebrospinal fluid, this will certainly affect the condition of the child or adult.
The 3rd ventricle of the brain is especially important in this regard, the norm of which is indicated below:
- Newborns -3-5 mm.
- Children 1-3 months -3-5 mm.
- Children 3 months - 6 years -3-6 mm.
- Adults -4-6 mm.
Common diseases of the third ventricle of the brain
Most often, the problem of impaired outflow of cerebrospinal fluid occurs in children - newborns and babies up to one year old. One of the most common diseases at this age is ICH () and its complication – hydrocephalus.
During pregnancy future mom undergoes mandatory fetal ultrasound, which makes it possible to identify birth defects development of the child’s central nervous system is still early stages. If during the examination the doctor notes that the 3rd ventricle of the brain is dilated, additional diagnostic tests and careful medical supervision will be needed.
If the cavity of the 3rd ventricle in the fetus becomes more and more dilated, in the future such a baby may require bypass surgery to restore the normal outflow of cerebrospinal fluid.
Also, all babies born at the age of two months (earlier if indicated) undergo mandatory medical checkup a neurologist who may suspect dilatation of the 3rd ventricle and the presence of ICH. Such children are sent to special examination brain structures – (neurosonogathia).
What is NSG?
Neurosonography is special type ultrasound examination of the brain. It can be performed on infants because they have a small physiological opening in the skull - the fontanel.
Using a special sensor, the doctor receives an image of all the internal structures of the brain, determines their size and location. If the 3rd ventricle is dilated in the NSG, more detailed tests are performed - computed tomography (CT) or magnetic resonance imaging (MRI) to obtain a more accurate picture of the disease and confirm the diagnosis.
Which doctors should you contact when diagnosing ICH?
If the 3rd ventricle of the baby’s brain is slightly enlarged and the mother has no serious complaints, regular monitoring by a local pediatrician is sufficient. Consultation with a neurologist and neurosurgeon is necessary if there is significant dilatation of the ventricles on ultrasound or symptoms of ICH:
- the child began to suck the breast worse;
- the fontanel is tense, protruding above the surface of the skull;
- the saphenous veins of the scalp are dilated;
- Graefe's symptom - a section of white sclera between the iris and eyelid when looking down;
- loud, sharp cry;
- vomit;
- divergence of the sutures of the skull;
- rapid increase in head size.
Doctors determine further tactics for treating a baby with: conservative means prescribing vascular medications, massage, physiotherapy; surgical – performing an operation. After therapy, children quickly recover, the activity of the nervous system is restored.
Colloid cyst of the 3rd ventricle is a disease common among adults 20-40 years old. It is characterized by the appearance of a benign round formation in the cavity of the 3rd ventricle, which is not prone to rapid growth and metastasis.
The colloid cyst itself does not pose any danger to human health. Problems begin if it reaches a large size and interferes with the outflow of cerebrospinal fluid. In this case, the patient experiences neurological symptoms associated with increased intracranial pressure:
- severe headache;
- vomit;
- visual impairment;
- convulsions.
Diagnosis and treatment of colloid cyst of the third ventricle is carried out jointly by a neurologist and a neurosurgeon. If the size of the formation is pronounced, determined on CT or surgery cysts. After the operation, the normal flow of cerebrospinal fluid is quickly restored, and all symptoms of the disease disappear.
Summing up
Thus, the third ventricle is important element liquor system, diseases of which can lead to serious consequences. Attentive attention to health and timely consultation with doctors will help you quickly and permanently cope with the disease.
The 3rd ventricle of the brain is a slit-like cavity bounded by the visual thalamus, located in the diencephalon. Inside, it has a soft shell, which is branched by choroid plexuses and filled with cerebrospinal fluid.
The physiological significance is extensive. Thanks to it, a flow of cerebrospinal fluid is possible for performing ablution. The circulation of cerebrospinal fluid will also occur.
All ventricles are united into common system, but the third one has some peculiarities. If deviations in its performance are detected, it is necessary to immediately consult a specialist, because the consequences can be extremely unfavorable.
So, its acceptable size should be no more than 5 mm in infants, and 6 mm in adults. However, only in it are autonomic centers, providing the process of inhibition of the autonomic nervous system, which is associated with visual function and is the central storehouse of cerebrospinal fluid.
Its pathologies have serious consequences depending on the ventricles of a different type. It plays a significant role in the functioning of the central nervous system, the performance of which depends on their functionality. Any violations may cause bad feeling, which often leads to disability.
The third ventricle externally resembles a kind of ring, which is located between two tubercles, and the inner surface contains a gray substance with subcortical centers. Below it is in contact with the 4th ventricle.
In addition, certain functions are distinguished:
- CNS protection;
- cerebrospinal fluid production;
- normalization of the microclimate of the organs of the central nervous system;
- metabolism, preventing unnecessary substances from entering the brain;
- circulation of cerebrospinal fluid.
Proper performance of the liquor system is a continuous and refined process. However, failure or any disturbance in the formation of cerebrospinal fluid is possible, which will affect the well-being of children or adults. Despite this, the norm is determined, which is different for each age:
- For infants, acceptable values are 3 – 5 mm.
- For children under 3 months, the value should not exceed 5 mm.
- For a child under 6 years of age – 6 mm.
- For an adult – no more than 6 mm.
Possible pathologies and diagnosis in children
Often, problems with the outflow of cerebrospinal fluid are observed in children - infants and children under 12 months of age. The main pathology is intracranial hypertension, and with more acute form– hydrocephalus.
During pregnancy, the parent is required to undergo an ultrasound examination of the fetus to detect the presence of congenital diseases nervous system in the early stages. If the examination reveals an enlargement of the 3rd ventricle, then it is worth taking additional diagnostic measures and carefully monitoring the development of the situation.
If the cavity continues to expand, then upon birth the child will need shunt surgery to normalize the outflow of cerebrospinal fluid. In addition, all newborns at the age of 2 months are sent for examination by a neurologist, who determines changes and the possibility of complications. Such children require specialized examination - neurosonography.
If the ventricle is slightly dilated, observations from a pediatrician are sufficient. If serious complaints arise, then you should seek advice from a neurosurgeon or neurologist. There are certain symptoms that indicate the presence of violations:
- the child sucks poorly at the breast;
- a small hole in the skull is tense and protrudes above its surface;
- the saphenous veins on the head are dilated;
- Graefe's symptom;
- a sharp and loud cry;
- vomit;
- the sutures on the skull are coming apart;
- the head increases in size.
If such symptoms are present, specialists prescribe a different treatment: prescribe vascular drugs, massage and physiotherapy, but surgery is possible. After therapeutic methods In a short period of time, children restore their health, and at the same time their nervous system.
Colloid cyst
It is one of the most common pathologies that are present in people under 40 years of age. A colloid cyst is characterized by the appearance of a benign tumor located in the cavity of the ventricle. At the same time, they are not observed fast growth and metastases.
Often it does not pose a serious danger to human health. Complications arise when the cyst increases in size, which impairs the outflow of cerebrospinal fluid. In this case, the patient experiences neurological symptoms caused by hypertension inside the skull. This is characterized by:
- Headache.
- Vomit.
- Vision problems.
- Cramps.
Diagnostics and the choice of optimal treatment depend on the neurosurgeon and neurologist. It is possible to find out what size the neoplasm is through an examination, with large sizes it is necessary to resort to surgical intervention. The main examination technique is neurosonography - ultrasound examination. This method is applicable to newborns because they have a small hole in the skull. Thus, thanks to a special sensor, the doctor receives information about the state of the brain organs exactly down to location and size. When the 3rd ventricle is enlarged, more accurate tests and diagnostic methods are needed - tomography. IN postoperative period the outflow is normalized, and the symptoms no longer bother you.
The third ventricle of the brain is a significant element of the cerebrospinal fluid system, the pathologies of which can result from many complications. Attention to one’s own health and timely examination medical centers will help prevent the development of the disease and cure the patient.
Dilatation, or expansion of the lateral ventricles, occurs due to the production of a large amount of cerebrospinal fluid, as a result of which it does not have time to be excreted normally, or due to the occurrence of obstacles to the exit of the cerebrospinal fluid. This disease most often occurs in premature babies due to the fact that the size of their lateral ventricles is much larger than in children born at term.
Separation of the choroid plexus in the stomach in fetuses with normal-sized cerebral ventricles on sonography: postpartum outcome. Isolated mild fetal fetal ventriculomegaly: clinical course and outcome. Mild fetal cerebral ventriculomegaly: diagnosis, clinical associations and outcomes.
Perinatal and neurological outcome with isolated fetal fetuses: a systematic review. Clinical outcome of mild fetal ventriculomegaly. Fetal cerebral ventriculomegaly: result in 176 cases. Prenatal isolated mild ventriculomegaly: result in 167 cases. Postpartum clinical and imaging follow-up of newborns with prenatal isolated mild ventriculomegaly: a series of 101 cases.
When diagnosing hydrocephalus, the size of the lateral ventricles is determined by their quantitative and qualitative characteristics. For this there is a sufficient number special techniques. In this case, the immediate depth of the lateral ventricles is measured, as well as the size of the cavity of the transparent septum located in the third ventricle.
The result of the development of children with antenatal moderate isolated ventriculomegaly. Outcomes in children with fetal mild ventriculomegaly: a case series. Fetal interferon-alpha serum suggests viral infection as the etiology of unexplained lateral cerebral ventriculomegaly.
Ultrasonography of prenatal and newborn. Effect of measurement errors on sonographic assessment of ventriculomegaly. The ratio of ventricular volume to whole brain volume was obtained as a secondary independent measure. In addition, these biomarkers are abnormal in the preclinical stage of mild cognitive impairment. These measurements are currently being explored in the Alzheimer's Disease Neuroimaging Initiative study as potentially useful biomarkers of disease progression.
Normally, the depth of the ventricles ranges from 1 to 4 mm. When these indicators increase by more than 4 mm, as a result of which their lateral curvature disappears and the shape becomes rounded, they speak of the beginning of expansion of the lateral ventricles.
Dilatation of the lateral ventricles is not considered a pathology, but a symptom of some disease. It is this reason that specialists have to diagnose.
Tau likely arises from the degeneration of neurofibrillary glomerular neurons and axons. There is evidence that this occurs in the preclinical stage of the disease, many years before symptoms of dementia appear. Hydrocephalus with normal pressure- This clinical syndrome, manifested by a triad of gait disturbances, incontinence Bladder and late dementia. Brain imaging studies reveal a pattern of ventricular dilatation consistent with communicating hydrocephalus type, in which ventricular dilatation is disproportionate to the degree of cortical atrophy.
Diseases in which dilatation of the lateral ventricles occurs.
Excessive accumulation of cerebrospinal fluid most often occurs as a result of a condition such as hydrocephalus. It is considered a fairly serious brain pathology. In this case, the process of cerebrospinal fluid absorption is disrupted, as a result of which it accumulates in the lateral ventricles, which leads to their dilatation.
Another reason for this failure may be due to the enrollment of too many moderate-to-severe patients. Like a number of current anti-amyloid experimental treatments that have failed in clinical trials, the intervention may also have come too late to restore or slow a well-established neurodegenerative cascade.
Data used in the preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative database. Biological samples are submitted to the University of Pennsylvania. Biomarkers studied include apolipoprotein E genotype, tau and phosphorylated tau 181p, Aβ 1-42, isoprostanes and homocysteine.
Excess cerebrospinal fluid appears with lesions of the central nervous system. In this case, the ventricles dilate due to the slow release of cerebrospinal fluid.
Disruption of the normal circulation of cerebrospinal fluid occurs due to the occurrence of neoplasms in the form of tumors or cysts, as well as as a result of traumatic brain injuries, inflammatory processes and hemorrhages in the brain.
Other cases of pathology
All subjects underwent extensive clinical diagnostic evaluation, including baseline tests mental status, neuropsychological tests, physical and neurological studies. Global measures of cognitive function included the Mini-Mental State Examination. Dementia severity was assessed using the Clinical Dementia Rating. The entry criteria for the study were any significant neurological disorder such as Parkinson's disease, multi-infarct dementia, Huntington's disease, normal pressure hydrocephalus, brain tumor, progressive supranuclear palsy, seizure disorder, subdural hematoma, multiple sclerosis, or history of significant head trauma followed by permanent neurological defaults or known structural brain disorders.
A common cause of dilatation is a congenital defect of the Sylvian aqueduct. It occurs in 30% of cases of hydrocephalus. Hydrocephalus can also be caused by an aneurysm of the vein of Galen and a subdural hematoma of the posterior cranial fossa.
Arnold-Chiari syndrome causes communicating hydrocephalus. In this case, a displacement of the brain stem and cerebellum occurs. This condition can also be caused by cytomegaly or toxoplasmosis.
Thus, cases with normal pressure hydrocephalus were excluded by clinical criteria without specific radiological exclusion of any person with dilated ventricles. More than 50 studies have demonstrated clinical sensitivity and specificity for these biomarkers of more than 80%. Anders Dale and colleagues in the Department of Neuroscience and Radiology at the University of California, San Diego. Phantom scanning was used to correct for gradient nonlinearities followed by normalization of image intensity.
Other causes of dilatation of the lateral ventricles.
Dilatation of the lateral ventricles can cause brain defects. At the same time, despite the fact that they do not affect health, observation by a specialist is still necessary.
Most often, dilatation of the lateral ventricles, not caused by serious diseases, does not lead to serious consequences. It can be a consequence of rickets, and also appear as a result of the specific structure of the skull.
Total ventricular volume and total brain volume were the main regions of interest. Total brain volume is a summary measure of the total brain parenchyma, including the brain, basal ganglia, medulla and cerebellum. An additional measure of total intracranial volume was obtained to control for between-subject variability in head size. This measure was intended to be insensitive to brain atrophy and thus reflect intracranial volume regardless of age or disease progression.
Dilatation and asymmetry of the lateral ventricles is detected when ultrasound examination brain. If in doubt, a repeat ultrasound scan is scheduled after a certain period of time.
And so, given:
Three-month-old child, slight asymmetry of the lateral ventricles. History C-section by the onset of fetal hypoxia. During a “manual” examination by a neurologist at 2 months, there is no traction on the arms (according to my observations, persistent traction appears at three months).
Pearson correlation coefficients comparing the ventricle with whole brain volumes were analyzed. For the entire sample, there was a significant interaction between the two volume measurements. Independent variables included ventricle and total brain parenchyma volume, as well as age. To assess whether ventricular volume may simply be a proxy for lateral ventricular enlargement secondary to early degeneration and atrophy of the medial temporal structures, significant relationships between biomarkers and hippocampal and entorhinal cortical volumes were also examined.
The situation is quite routine to consider the essence and problem of adequate assessment of hydrocephalic syndrome. In particular, to show how little relation “outpatient” cases of hydrocephalus have to cerebral palsy.
So, what is ventricular asymmetry? This means that one (or both ventricles in varying degrees) increased in size.
What is a cerebral ventricle? This is a cavity inside the brain. Take a peach, remove the pit from it and slam it shut. We will consider what formed at the site of the removed bone as a ventricle of the brain. Mentally pump it up with any liquid (whatever you like).
Graphs were created using the same software. Demographic information for the study sample is shown in Table 2. Tau was significantly associated with whole brain volume, but not stomach volume or age. In addition, the coefficient served as a correction factor for head size.
Mild cognitive defects
There was no significant effect of total intracranial volume when entered as a covariate in any of the above models. This finding suggests that blood-brain barrier dysfunction is not directly related to brain atrophy. The results of this study should be interpreted with great caution for a number of reasons. The ventricular volume measure is a global measure of the entire ventricular system. We cannot rule out the possibility that ventricular volume is simply a proxy for brain atrophy in certain adjacent brain regions, such as the medial temporal lobe, which may affect primarily the temporal horn.
Now let's think about what we can do with a peach to make our “stomach” increase in volume?
While you're thinking about it, I'll write an answer.
There are two ways to increase the volume of the brain ventricle (i.e. peach):
- pump it harder with liquid so that the elastic walls of the peach move apart under its pressure.
- cut out a larger cavity with a knife.
Now we are slowly moving from the peach to the brain.
These are rich areas of potential future research. Biomarkers in preclinical Alzheimer's disease. Cerebrospinal fluid tau and beta-amyloid: How well do these biomarkers reflect autopsy-confirmed diagnosis? Alzheimer's disease: the amyloid cascade hypothesis.
Other causes of dilatation of the cerebral ventricles
Towards a comprehensive theory of Alzheimer's disease. Hypothesis: Alzheimer's disease is caused by cerebral accumulation and cytotoxicity of amyloid beta protein. Associated incidence of Alzheimer's disease with normal pressure hydrocephalus: prevalence and shunt response.
We have just modeled two types of ventricular volume expansion: hypertensive and atrophic.
In 99% the cause of an increase in the volume of the ventricles of the brain (by medical language this is called internal hydrocephalus or simply hydrocephalus) is hypoxia. 1% accounts for infections and rare diseases, which we will not consider now.
Prevalence of Alzheimer's disease in patients studied for presumed normal pressure hydrocephalus: a clinical and neuropathological study. Unifying concept of Alzheimer's disease, vascular dementia and normal pressure hydrocephalus - hypothesis.
Alzheimer's diseases are associated with diseases characterized by increased intracranial or intraocular pressure. Homeostatic capabilities of the choroid plexus epithelium in Alzheimer's disease. Production and increased detection of amyloid beta protein and amyloidogenic fragments in cerebral microvessels, meningeal vessels, and the choroid plexus in Alzheimer's disease.
And so, let us remember that hypoxia, i.e. oxygen starvation at healthy brain always causes increased production of intracerebral fluid (or cerebrospinal fluid), which leads to intracranial hypertension (ICH).
Under the pressure of the cerebrospinal fluid, the ventricular cavity expands, which is what we see on ultrasound.
How dangerous is this?
As much as intracranial hypertension is expressed. Ideally, the patient feels only external discomfort. Anyone who has ever suffered a concussion has experienced it.
Alzheimer's Disease Neuroimaging Initiative. A practical method for assessing the cognitive state of patients for the doctor. The Clinical Dementia Assessment: A reliable and valid diagnostic and graded measure of dementia of the Alzheimer's type. Cerebrospinal fluid biomarker signature in neuroimaging subjects of Alzheimer's disease.
Whole brain segmentation: Automatic labeling of neuroanatomical structures in the human brain. Congenital and acquired infections of the central nervous system pose a serious threat to the developing brain, even in the face of appropriate treatment. Over the past five years, several reports have described ultrasonic features intracranial infection, including echogenic sulci, extra-axial fluid collections, ventricular enlargement, calcifications, abnormal parenchymal echogenicity, abscess formation, cystic degeneration of the brain parenchyma, intraventricular echogenicity, ventricular septations and irregularity and prominence of the ventricular walls.
In newborns, manifestations of hypertension syndrome can occur just as violently, but most often they are mild:
- Regurgitation (may or may not occur)
- Revitalization of postural reflexes (head tilting, etc.). But it may not be.
- A large percentage of children have no symptoms at all, but only an ultrasound picture of the brain, where it is written about the asymmetry of the lateral ventricles of the brain.
- Increase in head size. It may not be either.
What is the danger of ventricular dilatation due to excess cerebrospinal fluid?
These features enable ultrasound diagnosis of intracranial infection and help guide decisions that impact patient management. The cerebral ventricular system is considered to be the core of the mammalian central nervous system and plays several physiological roles. This is important when physically supporting the brain through buoyancy effects; it is a trophic mediator for global distribution wide range neuromodulators, neuropeptide hormones and neurotransmitters.
The cerebral ventricular system also contains the choroid plexus, which is responsible for the production of cerebrospinal fluid. Respiratory system gastrointestinal tract mammals have specialized regions called obstructive organs that allow the brain to not only perceive the peripheral endocrine and physiological environment, but also to respond by changing it with precision.
The ventricle is a cavity, an emptiness filled with water. Emptiness cannot think, cannot send signals to our muscles. Therefore, theoretically, cerebral palsy cannot develop due to ventricular enlargement.
The somewhat unpleasant symptoms described above, a slight tempo (temporary) delay in the motor sphere, are all that can threaten a “small asymmetry of the lateral ventricles of the brain.”
Ventricles, meninges and cerebrospinal fluid formation
The third ventricle, in turn, connects to the fourth ventricle, located in the pons and brain, through the aqueduct of Silvius. The fourth ventricle ends caudally in the central spinal canal and continues as the smallest midline structure through. The ventricular system of the brain is an extension of the central canal of the neural tube. As certain parts of the brain form, the central canal expands into well-defined ventricles, which are connected by thinner canals.
Exceptions are cases of severe hypertension, when a progressive accumulation of fluid in the ventricle compresses, damaging, the substance of the brain.
Now we will return to our peach again. Let's imagine that we are pumping liquid into the cavity left after removing the bone, building up pressure.
What will happen? Two options: either the pulp around the cavity will be compressed, or the peel will crack. Sometimes all together.
Something similar happens to the brain when too much energy accumulates in its cavities. a large number of cerebrospinal fluid: the brain substance surrounding the ventricles can change its properties, and therefore, nervous regulation can be disrupted.
Children are often helped by the fact that the bones of the skull (“skin”) are very elastic and are not fused together. This relieves some of the pressure on the brain.
The situation is complex, unlike the first one, it requires serious examination and treatment.
What can be reassuring? Only because it rarely happens “at home” and is more typical for children after severe intraventricular hemorrhages.
Now let's go back to the peach.
Remember the second way to increase the volume of the ventricular cavity? Yes, cut it with a knife. Sounds cruel. And when applied to the brain it is more than serious. This is the so-called atrophic hydrocephalus.
The role of a knife is most often performed by severe hypoxia. Sometimes infection, hemorrhage or rare metabolic diseases.
Since we are talking about damage to the brain substance, neurological disorders in the future are likely; the “threat of cerebral palsy” is often raised.
So what do we have? What is the most common cause of ventricular dilatation? normal reaction to mild hypoxia, does not affect the brain substance and does not lead to cerebral palsy.
In some cases, enlargement of the ventricles is caused by a decrease in the volume of brain matter, which is a formidable prognostic sign.
Now let's go back... no, not to the peach. Let's return to the child whose ultrasound revealed asymmetry of the ventricles of the brain.
What examinations should be performed in a child with suspected hydrocephalic syndrome?
- Estimation of monthly head growth. It can be performed by a local doctor and even by a mother. Simple but very informative method to assess the severity of hydrocephalus.
- Examination by a neurologist. But we remember that up to three months, a “manual” inspection is not very informative.
- Ultrasound of the brain. Well reflects the size of the ventricles.
- If the situation is considered serious, then additional examinations: computed tomography of the brain or MRI.
What is the mother's action algorithm?
- Ask how severe the enlargement of the ventricle is (ventriculomegaly). Typically, if the increase is significant, further consultation will be offered. With the option “slightly more than normal» will offer monitoring over time without leaving the local clinic.
- Be sure to clarify whether there is atrophy of the brain substance.
- Ask your doctor about the suspected cause of hydrocephalic syndrome. Clarification is required here: we are talking about the immediate cause, such as infection, hypoxia. There is no point in finding out whether the umbilical cord entanglement or a long period of pushing is to blame.
- Remember that neurological examination up to three months of age is uninformative.
- If the doctor pronounces the words “cerebral palsy”, “developmental disorder”, demand, in addition to the pills, additional examination: computed tomography, Dopplerography, referral to a specialized center. Because in this case the situation is too serious to be limited to Cavinton and dynamic examination.
- Visit a competent osteopath (not a charlatan).
- The last piece of advice is to seek alternative advice from medical practitioner at a serious government clinic. The fact is that many outpatient doctors have never seen truly severe cases, so they tend to exaggerate the severity of the problem.
I sincerely wish everyone exactly the last option - a false alarm.
Third (III) ventricle, ventriculus tertius (see Fig. , , , , , , , , , ), unpaired, located in the midsagittal plane and communicates with the lateral ventricles and the IV ventricle.
The cavity of the third ventricle is slit-like, limited by 6 walls: upper, anterior, lower, posterior and two lateral.
Upper wall of the third ventricle – vascular basis III ventricle, tela choroidea ventriculi tertii(see Fig.) is a formation of two plates - the upper, dorsal one, lying under the fornix and corpus callosum, and the lower, ventral one, facing the cavity of the third ventricle. Between both plates there is a loose connective tissue. It has two internal veins brain, which, having received blood from the veins of the thalamus and striatum, veins of the transparent septum and choroid plexus, lateral ventricles, flow into the large vein of the brain. From the ventral plate a number of villi project into the cavity of the third ventricle, which form choroid plexus of the third ventricle, plexus choroideus ventriculi tertii. Anteriorly, at the interventricular foramen, it connects with the plexuses of both lateral ventricles.
The lateral walls of the third ventricle are formed by the medial surfaces of the thalami. Vertical bundles pass under the ependyma of the lateral wall periventricular fibers, fibrae periventriculares, connecting the medial group of thalamic nuclei with the hypothalamic nuclei.
In front, the cavity of the third ventricle is limited by the columns of the fornix and the anterior commissure adjacent to the back surface end plate. Between the anterior tubercle of each thalamus and the anterior columns of the fornix, a interventricular foramen, foramen interventriculare, connecting the third ventricle with the lateral ones.
Ventral to the posterior commissure there is a cluster of specialized ependymal cells - tanycytes. These cells perform a secretory function and are involved in the transport of hormonal and mediator substances from adjacent tissue to the cerebrospinal fluid and in the opposite direction. This portion of the ependyma of the third ventricle is designated as subcommissural organ.
Between the diverging columns of the arch and the anterior commissure there is a small, triangular-shaped depression. It also contains a cluster of specialized ependymal cells - subfornical organ.
In the area where the end plate adjoins the optic chiasm, a visual recess, recessus opticus. On early stages development of the brain, it represents the terminal section of the cavity of the brain (nervous) tube.
The lower wall, or bottom, of the third ventricle is the formation of the hypothalamus, which lies at the base of the brain.
The posterior wall of the third ventricle is mainly represented epithalamic commissure, commissura epithalamica. It is a curved plate protruding into the ventricular cavity and consists of transverse fibers. Below it is located pineal recess, recessus pinealis, passing into the cerebral aqueduct connecting the third ventricle with the fourth, above it - suprapineal recess, recessus suprapinealis, and even higher - the soldering of leashes.
