Enlarged ventricles, not all hydrocephalus, but also these reasons...

*Only for medical professionals to read and refer to neurologists, it has been collected! 1.
Local enlargement of lateral ventricle 1.
Localized brain atrophy After trauma, brain atrophy, brain atrophy after infection, brain atrophy after cerebral infarction, CT shows that the brain parenchyma near the enlarged part of the ventricle is sheet-like low-density focus MR: T1WI shows low signal, T2WI shows high Signal
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At the same time, the sulcus and subarachnoid space widened
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2.
Lateral ventricle neuroepithelial cysts are usually located in the triangle of the lateral ventricle, with thin cyst wall, usually unclear.
Because the cyst contains cerebrospinal fluid, CT and MR both show cerebrospinal fluid signals
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3.
The anatomical variation is characterized by no lesions in the nearby brain parenchyma, no enlargement of the sulcus and subarachnoid space or abnormal brain structure
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4.
The isolated temporal (inferior) angle of the lateral ventricle is caused by obstruction of the flow of cerebrospinal fluid in the temporal horn of the lateral brain.
It is often caused by lesions of the lateral ventricle, including intraependymmal hemorrhage, meningioma, and choroidal papilloma.
It can also be caused by Compression of the lesion around the triangle of the lateral ventricle
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2.
Enlargement of one side of the ventricle 1.
In normal variants, a considerable number of bilateral ventricles are inconsistent in size, and the asymmetric side of the ventricle is significantly larger than the other
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Clinically, intelligence and mental development are normal and have no clinical significance
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2.
Atrophy of one cerebral hemisphere can be caused by many reasons, such as cerebral infarction, trauma, hemorrhage and infection
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The most common cause is a large area of ​​cerebral infarction caused by vascular occlusion
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CT and MRI showed that the affected side of the ventricle was enlarged, the amount of brain tissue was reduced, and the midline was shifted to the affected side.
In severe cases, the sulci and gyrus disappeared
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3.
Cerebral trigeminal nerve hemangioma is also known as facial hemangioma syndrome.
CT plain scan is characterized by gyrus-like, orbit-like, arc-like or serrated calcification in the brain parenchyma of one hemisphere
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Due to the blood supply disorder on the affected side, brain parenchymal atrophy is often caused, so the affected side ventricles can be enlarged, the cranial cavity becomes smaller, and the cranial plate is thickened
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There are purple-red vascular nevi in ​​the typical calcification and clinical trigeminal extension area in the brain
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4.
One side of the interventricular foramen is blocked.
Cerebrospinal fluid is mainly produced in the choroidal plexus of the ventricle
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When one side of the interventricular foramen is blocked, the cerebrospinal fluid produced by the choroidal plexus of the ipsilateral ventricle cannot enter the third ventricle, and the cerebrospinal fluid accumulates in the lateral ventricle.
CT and MR examinations show that one side of the lateral ventricle is enlarged.
When the enlargement is obvious, there may be a midline structure facing The main causes of lateral displacement are tumors, cysts, cysts and inflammatory adhesions near the interventricular foramen
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The main points for determining that the expansion of one side of the lateral ventricle is caused by the obstruction of the interventricular foramen include: one side of the lateral ventricle is clearly dilated and has tension; the transparent septum shifts to the opposite side; there is no other surrounding area around the enlarged side of the ventricle that can cause the expansion of the lateral ventricle Reasons that can be explained
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5.
Periventricular leukomalacia is mainly related to ischemia, hypoxia and infection.
It is common in premature infants and is the main cause of cerebral palsy in premature infants
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Since the blood supply of the white matter around the ventricle comes from the terminal arteries in the ventricular area and the distal ventricular area, the collateral circulation of the deep perforating branch of the terminal artery in immature infants has not been established, and the white matter around the ventricle is sensitive to ischemia and hypoxia in the late embryonic stage
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Therefore, periventricular automalacia is more common in premature infants
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Because the lesions are often bilateral, the bilateral ventricles often expand at the same time
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Cerebral white matter softening lesions appeared as patchy low-density lesions in white matter on CT scan, MR T1-weighted map showed low signal, and T2-weighted map showed high signal
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3.
Bilateral ventricular enlargement 1.
General brain atrophy General brain atrophy often involves gray matter and white matter at the same time, and may manifest as bilateral lateral ventricle enlargement
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And it is the most common cause of mild symmetrical enlargement of bilateral ventricles
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Especially in patients with white matter atrophy
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    The enlargement of the lateral ventricle caused by general brain atrophy is usually symmetrical, with no shift in the midline
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It is characterized by symptoms of cortical atrophy such as brain sulci and brain fissure widening at the same time
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General brain atrophy can be seen in normal elderly people.
The main reasons are: ① CT and MR examinations of age-related brain atrophy show mild enlargement of the ventricles and cisterns, and mild enlargement of the sulci, often more obvious in the frontal lobe and parasitic
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②Alzheimer's disease.
In addition to the general manifestations of general brain atrophy, the temporal lobe atrophy is often obvious and early, so the lateral ventricle enlargement is more obvious with the temporal horn
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The severity of neuronal loss in Alzheimer's disease was hippocampus, posterior temporal lobe, frontal lobe and parietal lobe in order of severity
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③Huntington's disease (chorea) is an autosomal dominant degeneration of the basal ganglia and cerebral cortex
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Mainly damage the basal ganglia and cerebral cortex, and the caudate nucleus and putamen are the most obvious
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Small ganglion cells are severely damaged, large cells are also reduced, Nissl bodies disappear, nuclear pyknosis, amyloid bodies appear, as well as demyelination changes and glial hyperplasia.
The involvement of the basal ganglia is often the most obvious and the earliest
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The clinic is mainly based on 3 major characteristics: choreography, dementia, and family history
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④Parkinson's disease, also known as tremor, is a common extrapyramidal disease
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Clinically characterized by tremor, muscle rigidity and dyskinesia
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The first symptom of tremor feeding is obvious when resting and quiet
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In addition to CT atrophy, sometimes calcification of the basal ganglia can be seen
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There are often multiple hyperintensity spots in the basal ganglia and white matter on MR T2WI
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⑤Pick’s disease, also known as lobar sclerosis, is more common in women.
The peak incidence is 50 years old.
The clinical manifestation is progressive dementia
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CT and MR often focus on atrophy of the frontal and temporal lobes
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Another feature is that bilateral atrophy is often inconsistent, the left side is more obvious, the front half of the superior temporal gyrus is atrophied, and the back is often normal
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⑥ Jakob-Creutzfeldt's disease, a kind of encephalopathy characterized by rapidly progressive dementia, is characterized by symmetrical enlargement of the lateral ventricles and widening of the sulci-brain fissure
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Short-term reexamination showed that the degree of atrophy was significantly worsened, and diffuse white matter demyelination changes may occur in the late stage
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⑦ other causes such as hypoxia, poisoning, physical trauma and malnutrition
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2.
The expansion of the lateral ventricle in premature infants is relatively large in the early embryonic stage.
As the development matures, the lateral ventricle gradually becomes smaller and reaches a normal size at 36 weeks of the embryo.
Therefore, preterm infants often show mild symmetry of bilateral lateral ventricles.
Sexual expansion, Long Qi is a premature baby born 30 weeks ago
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Can be combined with or without intracranial hemorrhage in premature infants
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3.
Megacerebral malformation.
Megacerebral malformation can simultaneously show symmetrical enlargement of bilateral lateral ventricles
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Usually mild
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This kind of giant brain malformation can be a symptom of many diseases: such as Alexander disease, spongiform degeneration, Soto's syndrome and so on
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The common situation is that many large-headed children have normal clinical mental development and physical development, no manifestations of increased intracranial pressure, and no signs and symptoms of the nervous system
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Soto's syndrome, also known as cerebral gigantism, manifests itself in the neonatal period with a marked increase in physical development, macrocephaly with megacephaly, delayed mental development, and special body, protruding forehead, blepharoplasty, tilted eyes The distance is too wide, the mandible is thin and prominent, growth hormone and endocrine examinations are normal, and the head CT and MR examinations are mainly manifested as giant brains and lateral ventricles
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The diagnosis is mainly combined with the above-mentioned clinical conditions
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4.
Abnormalities of congenital brain development.
Many kinds of brain development abnormalities can simultaneously manifest the right ventricle enlargement, including forebrain anemia, split brain malformation, anencephaly and giant gyrus
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(1) Forebrain nonscission malformation: refers to a series of malformations of varying degrees located in the midline, involving the brain, face, cerebellum and cerebellum
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The forebrain could not be separated, and it was incomplete or complete, and the telencephalon and the diencephalon could not be distinguished
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According to the degree of brain and facial deformities, they are divided into leafless type, semi-lobe type and simple lobe type
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Forebrain without lobules is the most serious.
There are no fissures between the cerebellar hemispheres.
The single ventricle with horseshoe or crescent-shaped enlarged crosses the midline and communicates with the dorsal capsule
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The thalamus merge with each other, and the facial deformities range from too close to the one-eyed deformity, and often die in the fetus or neonatal period
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Hemilobe-type forebrain afissure malformation has partial fissures in the forebrain, forming longitudinal cerebral fissures and falx cerebrum of different developmental degrees
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The two cerebral hemispheres are not completely separated in the anterior part, but the occipital lobe and the bilateral ventricle body are separated, and the thalamus is not completely separated
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The third ventricle and hippocampus are underdeveloped, the corpus callosum is only visible in the depressed part, and other parts are absent, and the frontal lobe and the anterior part of the basal ganglia are unclear
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The clinical manifestations are that the eyes are too close, cleft lip, cleft palate and other facial deformities, the lateral ventricle is single and obviously enlarged
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The unilobular forebrain acephalic malformation is only slightly different from the normal developing brain, such as the absence of transparent septum or the incomplete separation of bilateral frontal lobes
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  (2) Split brain malformation: embryonic brain development goes through six main stages: ① dorsal induction stage; ③ ventral induction stage; ③ neuroproliferation stage; ④ neuron migration stage; ⑤ tissue formation stage; ⑥ myelination Stage
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Split brain malformation occurs in the stage of neuron migration
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The split brain malformation can involve one or both of the cerebral hemispheres, and the split brain malformation is located on the side
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It often involves the central anterior and posterior gyrus and occasionally other parts of the cerebral hemisphere
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The fissures of cleft brain deformities can be very narrow, and the gray matter on both sides of the fissures is close to each other, which is called closed type
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The fissure can also be very wide, with cerebrospinal fluid in the middle, separated
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Separate split brain malformation needs to be distinguished from penetrating malformation cysts.
The fissure of split brain malformation must be surrounded by a gray matter structure on both sides, and there is no brain gray matter surrounding the penetrating malformation cyst
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Whether there are gray matter structures on both sides of the fissure is a reliable sign to distinguish between a split brain malformation and a penetrating malformation cyst
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The gray matter on both sides of the fissure may be abnormal and may be multi-cerebellar
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Split brain malformations can also be associated with heterotopic brain gray matter
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The separated type is easy to show on CT, and the closed type is sometimes easily missed.
MRI can easily identify the gray matter structures on both sides of the fissure
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Split brain malformations often merge with a transparent septum, enlarged lateral ventricles, and irregular edges of the ventricles at the split brain malformations.
Fissures or triangular diverticula pointing to the cleft are often seen
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Clinically, split brain malformations often present with epileptic seizures, and other neurological symptoms can range from very mild to very severe
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It mainly depends on the severity of the brain tissue defect caused by the split brain malformation
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Symptoms of unilateral closed split brain malformation are usually mild, and symptoms of bilateral split brain malformation are more obvious
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 (3) Acerebrospinal gyrus and giant gyrus.
Acerebrospinal gyrus and giant gyrus are a group of gyrus development abnormalities caused by abnormal neuron migration
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Giant brain gyrus is also called smooth brain
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The giant gyrus refers to the existence of part of the gyrus, these gyruses are abnormally enlarged and widened, and the sulci become shallow
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The giant brain gyrus is mainly located in the frontal and temporal regions
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The upper back of the brainless gyrus should be located at the parietal and occipital areas
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Clinically, children with anencephaly and giant gyrus both have microcephaly and minor facial abnormalities.
Complete anencephaly usually die before the age of two.
Incomplete gyrus can often survive for a long time
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Both CT and MR can well show the anencephaly and giant gyrus.
The surface of the cerebral hemisphere is almost smooth.
Only a few broad, thick and flat gyrus can be seen, and the sulci are absent
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The gray matter of the brain thickens, the white matter of the brain becomes thinner, and the interface of the gray matter is abnormally smooth, and no white matter extends into the gray matter
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The common transparent septum has lateral ventricle enlargement and the subarachnoid space enlargement
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5.
Bilateral interventricular foramen obstruction is the same as one-sided interventricular foramen obstruction.
After bilateral interventricular foramen obstruction, it can be manifested as symmetrical or asymmetrical enlargement of bilateral lateral ventricles.
The enlargement of the ventricles is usually very significant, and there are many around the ventricles.
In interstitial cerebral edema, the cause of obstruction of bilateral interventricular foramen is the same as that of one interventricular foramen
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May also be accompanied by narrow aqueduct
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Diagnosis points: The bilateral lateral ventricles are enlarged and the third ventricles are normal in size
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6.
Periventricular leukomalacia is mainly related to ischemia, hypoxia and infection
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It is common in premature babies
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The common cause in premature infants is related to the time when brain damage occurs in the embryonic stage.
Brain damage in the early and mid embryonic stage mainly causes developmental malformations, and the later stage mainly causes cerebrovascular changes
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Since the blood supply of the white matter around the ventricle comes from the terminal arteries in the ventricular area and the distal ventricular area, the collateral circulation of the deep perforating branch of the terminal artery in immature babies has not been established, and the white matter around the ventricle is sensitive to ischemia and hypoxia in the late embryonic stage
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Therefore, periventricular leukomalacia is more common in premature infants
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Due to the softening and atrophy around the lateral ventricle, the enlarged lateral ventricular rim is often irregular and not smooth.
This irregularity and unevenness are the characteristics of the disease caused by the enlargement of the ventricle
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In addition, the disease is characterized by decreased white matter and patchy softening of the white matter.
When the white matter is severe, the white matter disappears in some areas, and the cerebral cortex is close to or even connected to the lateral edge of the ventricle
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CT showed patchy low-density foci
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MR showed low signal on T1WI and high signal on T2WI
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7.
Optic-septal dysplasia is a rare congenital malformation, which mainly includes: ① absent or hypoplastic transparent septum; ② dysplasia of optic nerve, optic chiasm and funnel; ③ different degrees of hypothalamic-pituitary dysfunction
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The imaging findings may be mild, including the absence of a transparent septum, thinning of the optic nerve and optic chiasma, small optic canal, enlargement of the three ventricle optic recesses, enlarged bilateral lateral ventricles, and a square anterior horn of the lateral ventricles
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It is more common in women, and may present with diabetes insipidus, visual impairment and subthalamic dysfunction
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8.
The dysplasia of the corpus callosum is induced in the late stage of brain development on the ventral side.
The newly formed dorsal part of the side wall of the mouth of the cerebellum is thickened and indented, and it extends posteriorly along the not fully developed cerebral interhemispheric fissure
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Two months later, a commissural cell frame of the corpus callosum fiber is formed.
After the cell frame is formed, the corresponding part of the corpus callosum develops immediately.
The knee develops first, then the body and the pressure part, and the corpus callosum mouth located behind the knee of the corpus callosum develops last.

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If harmful factors occur during the development of the corpus callosum, it may lead to dysplasia of the corpus callosum, which is completely absent or partially absent
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It is often manifested as the presence of the knee or the presence of the knee and body, and the lack of pressure and corpus callosum mouth
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The dysplasia of the corpus callosum can be seen alone, but it is more common to be accompanied by other malformations of the central extension system, including lipoma around the corpus callosum, encephalocele, communicating hydrocephalus Chaarii malformation, Dandy-Walker cyst, cleft cerebral malformation and so on
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Clinically, it can be asymptomatic or have only mild clinical symptoms.
Clinical examination shows that the eye distance is too wide, macrocephaly, and mental retardation
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In the absence of the corpus callosum, the anterior horn of the upper lateral ventricle in the coronal position of MR appears crescent-shaped, and the body of the lateral ventricle is separated and runs vertically and parallel
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4.
Simultaneous expansion of the third ventricle and lateral ventricles 1.
Aqueduct stenosis: The midbrain aqueduct is the narrowest passage in the ventricular system and the most common site where the circulation of cerebrospinal fluid is blocked
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Complex cause aqueduct stenosis, include: ① congenital stenosis; ② gutter surrounding gum degeneration; ③ aqueduct adhesions
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Congenital developmental stenosis can be linear stenosis, bifurcated stenosis, or diaphragm formation
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Glue around the aqueduct is mostly caused by inflammation, which is mainly seen after congenital intrauterine infection, especially toxoplasma infection
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Aqueduct adhesions are mainly seen after intracranial infection and hemorrhage, can occur in the embryonic period, and can also be seen at any age after birth
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The stenosis caused by adhesion of the aqueduct is mostly located at the distal end of the aqueduct
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The length of the stenosis is usually 2-5mm, and the aqueduct at the proximal end of the stenosis can be expanded like a bell mouth
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When the aqueduct is stenosis, the third ventricle is often enlarged significantly.
The anterior optic and infundibular crypts of the third ventricle expand or disappear, and the pineal and suprapineal crypts in the posterior part of the third ventricle are obviously protruding to the cerebellum.
The pool herniated
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In severe cases, it can oppress the cerebellum
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2.
Inferior cerebellar tonsil hernia malformation is also known as Chiari's malformation, that is, the cerebellar tonsils move down into the spinal canal, and the medulla oblongata and the fourth ventricle are elongated and partially shifted downwards.
They can be divided into 3 types, and each type often has hydrocephalus.
The third ventricle and the lateral ventricle are enlarged
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Type I: If only the cerebellar tonsils move down
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Tonsil below the lower edge of the foramen magnum connection than 5mm, no brain stem and to the fourth ventricle changer type Ⅰ
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Type Ⅱ: In addition to the downward shift of the cerebellar tonsils, part or all of the fourth ventricle descends below the foramen magnum
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Type Ⅲ: Type Ⅲ if the whole cerebellum and four brains herniate into the foramen magnum below
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5.
Enlargement of all ventricles 1.
Communication hydrocephalus, also known as ventricular obstructive hydrocephalus, is hydrocephalus caused by cerebrospinal fluid circulation after the exit of the fourth ventricle
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It is often located in the subarachnoid space, with the basal cistern the most common
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The main causes include meningitis, subarachnoid hemorrhage, meningeal metastasis, trauma, venous sinus thrombosis, post-cranial surgery and cerebrospinal fluid absorption dysfunction
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The clinical manifestations are mainly caused by increased intracranial pressure, which may include headache, vomiting, diplopia, and papilledema
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In communicating hydrocephalus, the expansion of the fourth ventricle usually occurs later, so in the early stage, it may only show the expansion of the lateral ventricle and the third ventricle
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It should be distinguished from obstructive hydrocephalus caused by aqueduct stenosis
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MR sagittal T1-weighted image is the best way to directly observe whether the aqueduct has stenosis
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In addition, it needs to be distinguished from general brain atrophy.
When the brain is atrophy, the sulci-brain is widened, and when the hydrocephalus, the sulci is narrowed and disappears or is normal
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Moreover, the expansion of the third ventricle is not obvious, and the expansion of the third ventricle is more obvious when the brain is atrophy
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In the late stage, communicating hydrocephalus appears and the entire ventricular system is generally enlarged and the sulci is normal or narrowed and disappeared
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2.
Normal pressure hydrocephalus is actually a special type of communicating hydrocephalus.
Also known as occult hydrocephalus, low-position hydrocephalus or chronic communicating hydrocephalus
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The normal cerebrospinal fluid pressure may be due to the decrease in the compensatory secretion of cerebrospinal fluid and the enhanced absorption, which makes the pressure of the cerebrospinal fluid relatively normal; ②the cerebrospinal fluid is absorbed through the ependyma to keep the cerebrospinal fluid pressure constant; ③the tension of the brain parenchyma is reduced
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Normal pressure hydrocephalus may be caused by occult subarachnoid hemorrhage or infection, and may also be secondary to other brain diseases
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Including subarachnoid hemorrhage, traumatic brain injury, inflammation, adhesions after brain surgery
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Normal pressure hydrocephalus is common after 50 years of age
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The clinical manifestations are actually the manifestations of chronic communicating hydrocephalus plus brain atrophy.
Its typical clinical manifestations are dementia, abnormal gait and incontinence, which are progressively worsening
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A few cases also have limbs and transient disturbance of consciousness
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CT and MR examination showed general ventricle enlargement, but the sulci did not narrow or disappear
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Or it may show widening of sulci and brain fissure, which is difficult to distinguish from brain atrophy
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Normal pressure hydrocephalus can also only show brain atrophy without ventricular enlargement.
Therefore, when the clinical symptoms are typical, only brain atrophy can not exclude the diagnosis of normal pressure hydrocephalus
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3.
Fourth ventricle outlet obstruction Simple fourth ventricle outlet obstruction is mostly caused by adhesions, which is rare in clinical practice
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After adhesion, obstructive hydrocephalus is caused, and all ventricles are enlarged, but the enlargement of the fourth ventricle is usually the most significant, and it is often difficult to distinguish from a cyst in the fourth ventricle
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The most effective way to distinguish is to perform ventricle anaphora CT examination.
If it is a cyst, it will show a round filling defect in the fourth ventricle.
When the outlet of the fourth ventricle is blocked, the fourth ventricle will be filled with cerebrospinal fluid
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4.
Dandy-Walker's syndrome is also known as congenital atresia of the lateral foramen in the fourth ventricle
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In the early embryonic stage, the median foramen and lateral foramen of the fourth ventricle are closed, resulting in cystic expansion of the fourth ventricle, accompanied by dysplasia of the cerebellar vermis and hemispheres.
The posterior fossa is enlarged and the tentorium is raised
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Hydrocephalus in this disease is usually seen in infancy, or exists after birth, but does not develop until adulthood
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5.
Four ventricle cysts Four ventricle cysts can cause obstruction and enlargement of the entire ventricular system
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6.
Isolated fourth ventricle When the aqueduct and the outlet of the fourth ventricle are severely narrowed or completely blocked, the fourth ventricle is isolated.
This situation is called isolated fourth ventricle
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Source of this article: Xinxiang Medical Imaging Review of this article: Deputy Chief Physician Li Tuming Responsible Editor: Mr.
Lu Li Copyright Statement Timeliness, as well as the accuracy and completeness of the cited information (if any), make any promises and guarantees, and assume no responsibility for the outdated content and the possible inaccuracy or incompleteness of the cited information.

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Relevant parties are requested to check separately when adopting or using this as a basis for decision-making
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