The fontanel (xìn mén) refers to two "skylights" with no bones on the top of the head when a baby is born, which is called "fontanel" in medicine. Generally, the posterior fontanel is closed 3 months after birth, and the anterior fontanel will not be closed until 1.5 years old. People often say "skylight" or "fontanel" mainly refers to the front fontanel.

The skull consists of six bones. After the baby is born, because the skull is not fully developed, there are gaps between the bones, and two areas without bone cover are formed on the top of the head and behind the pillow, which are called the anterior fontanel and the posterior fontanel respectively.

The surface of fontanel is scalp, below it is meninges, and below it is brain and cerebrospinal fluid. Put your finger gently on the fontanel, and you can feel the beating. That is, cerebrospinal fluid pressure changes with heartbeat and blood pressure, which is consistent with pulse. When a normal baby is seated, the fontanel is slightly depressed. fontanel

The position of fontanel and the structure of newborn skull, cerebrospinal fluid in the brain, blood and tissue fluid in the body are constantly exchanged and kept in balance. When the body loses more water, the cerebrospinal fluid in the ventricle will also decrease, the pressure will decrease, and the fontanel will be obviously depressed. If the baby has this symptom after vomiting and diarrhea, it means that the body has been moderately dehydrated and needs to be replenished in time. Otherwise, due to the baby's poor natural adjustment ability and insufficient tolerance, circulatory failure may occur, which is life-threatening; Extremely thin infants with severe malnutrition due to improper feeding will also have fontanel depression. At this time, it is necessary to strengthen nutrition and feed reasonably. Very few babies have small heads because of maternal infection or other diseases during the embryonic period. The head circumference was small at birth, and the fontanel was closed in advance 5-6 months after birth, resulting in microcephaly; The head is small and pointed, the forehead is narrow, the bridge of the nose collapses, and the jaw shrinks back, accompanied by mental retardation. In children with cretinism caused by hypothyroidism, fontanelle will also be delayed; At the same time, there are few and light eyebrows, nose bridge collapse, wide eye distance and mental retardation. , can be treated with thyroxine.

Infant growth is particularly rapid, and bone development needs vitamin D and calcium. If it is not supplemented in time, it is easy to suffer from rickets. After birth 18 months, the fontanel is still not closed, resulting in "square skull" deformity, and the skull feels like a ping-pong shell (osteomalacia). In addition, it can also form bone beaded changes, chicken breasts, O-shaped or X-shaped legs and other deformities.

When a few babies grow to 5-6 months, the fontanel is only the size of a finger, which seems to be about to close, but it is not ossified. This is not premature closure, as long as the head circumference is not less than 33-34 cm at birth, 46 cm at 1 year, and 47-48 cm at 2 years old, it is normal and there is no need to worry.

Some people think that the fontanel can't be touched, and even think that the fontanel will become dumb, so the baby will accumulate black scabs, which is very unsanitary. The fontanel should be cleaned like the scalp in other parts, but the action should be gentle when washing.

Have you noticed that there is a small soft place above the baby's head, and sometimes you can see it jumping up and down. This is the baby's front fontanel. It is a rhombic space between bilateral frontal bone and bilateral parietal bone. When the newborn is born, the line connecting the opposite midpoint is about 1.5-2 cm. The head circumference increased rapidly in the first few months, and the anterior fontanel also became larger, reaching the maximum of 2.5-3 cm in about 6 months. Later, with the gradual ossification of the skull, the anterior fontanel gradually became smaller. Some children are locked up at the age of 1, at the latest.

A triangular gap is formed between the parietal bone and occipital bone on both sides of the anterior fontanel, which is usually closed or small at birth and can only accommodate one fingertip, except for premature infants.

If the newborn delivered through the birth canal is born naturally, the seams between the skulls may overlap. After birth, with the increase of head circumference, the skull suture can be slightly separated and closed 3-4 months after birth. The closure of anterior fontanel and suture reflects the ossification process of skull, which leads to microcephaly. Too late closure is more common in rickets, hydrocephalus or dementia (hypothyroidism). If you have fontanel, early closure of suture or late closure of suture, you should seek medical advice in time.

The front fontanel is flat when it is normal, but it can be sunken when the baby vomits frequently or loses a lot of water due to diarrhea. Meningitis, encephalitis, excessive vitamin A, sometimes high fever caused by upper respiratory tract infection or other reasons, such as acute rash in children, can all cause swelling or bulging of the anterior fontanel. When the baby has a fever or vomits, he should pay more attention to the changes of the anterior fontanel. If there is depression or swelling, he should go to the hospital immediately.

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Folding front fontanel

Touch the baby back and forth along the center line of the head, and you will find that there is an opening in the front and back of the baby's skull, which is soft to touch, and the front end is called the front chimney door, which is rhombic. It is the largest suture intersection on the skull, because there is no bone block here, which is slightly concave and soft compared with other parts, and there will be a slight beating feeling. After the baby was born for 6 months, the area of the anterior fontanel became smaller with the ossification of cranial suture, and 1 year was closed, and it was replaced by bone at the latest.

Fold the fontanel back

The rear chimney door is located behind the baby's head, at the junction of the occipital bone and the two parietal bones. It is small in size and sometimes even out of reach. The rear chimney door is close to being closed when the baby is born, or it can only accommodate the fingertips, and it is closed about 2-4 months after birth.

Although the baby's fontanelle is small, it is an important window to reflect the baby's health. Within the baby 1 year, many diseases can be found as soon as possible by observing this small window, so that the baby can be diagnosed and treated as soon as possible. Therefore, mommy should know more about the normal development process of the baby's fontanel and the abnormal phenomena that are easy to appear.

Fold and edit the relevant information in this paragraph.

When does the folding fontanel close?

There is a soft place on the baby's head, and sometimes you can see the beating. It's medically called fontanel. There are two main fontanels at birth: one is called Jingfontanel, which is located in front of the head and consists of the anterior upper corners of the parietal bones on both sides connected with the frontal bone. The oblique diameter at birth is 2.5 cm, and it usually closes at the age of 1 ~ 1.5; The other is called Houfontanel, which consists of parietal bone and occipital bone. In the back of the head, it is usually small or closed at birth and closed at the latest 2 ~ 4 months.

What are the conditions for early and late closure of fontanelle?

The main content of measuring skull development when fontanel is closed early or late. Early or late closure is a sign of abnormal growth and development. In traditional Chinese medicine, fontanel protrusion is called fontanel filling, fontanel depression is called fontanel depression, and fontanel delayed closure is called craniectomy. Late closure of fontanelle is more common in rickets, hydrocephalus, dementia and overgrowth of infants.

The fontanel on the baby's head is usually closed in 12- 18 months. Fontanel closure is a window reflecting brain development. If it is closed 6 months ago, it means that the child may have microcephaly or brain hypoplasia. 18 months later, it will be too late. Such children may have hydrocephalus, rickets and short stature. The fontanel bulge indicates that intracranial pressure is increased. This child may have meningitis, encephalitis and vitamin A poisoning. Children with fontanel depression may be due to dehydration and malnutrition. If the fontanelle closes early, but as long as the head circumference is long, don't worry. If you find that the fontanel door is abnormally closed, you should immediately take your child to the hospital for further examination.

Can I wash the folding fontanel door?

The fontanel is a gap left by incomplete development of the head and skull when the fetus is born. The posterior fontanel usually closes within three months after birth, and the anterior fontanel closes about 1 ~ 1.5 years after birth. Because there is no hard skull covering at the fontanel, we should pay attention to protection to prevent brain damage.

When washing the baby's hair. You can wash the fontanel door, but the action should be gentle and you can't scratch it with your fingers. Don't overheat the shampoo, you should use warm water.

Some babies have tan greasy scales on their foreheads, which is seborrheic dermatitis of babies. You can use sterilized cotton to smear paraffin oil or refined vegetable oil on the scales, soften them and then gently wipe them off with sterilized cotton. Do not forcibly remove it. This disease can heal itself, as long as it is not infected, there is no need to apply any medicine. When washing your hair, because your baby's skin is delicate, you should use neutral soap with little irritation.

Normal development process of folding fontanel

* The human skull consists of six bones, and the front fontanel and the back fontanel have been formed when the baby is born.

* When the baby was born, the skull was not fully developed and there were gaps between the bones.

* After the baby is born, two special areas with no bones and only scalp cover are formed on the top of the head and behind the pillow. These two special areas are called anterior fontanel and posterior fontanel respectively.

* Under normal circumstances, the size of the baby's front chimney door is about 1.5×2cm. From the outside, the fontanel in front looks flat or slightly concave.

* In the first few months after birth, the anterior fontanel will increase slightly with the gradual increase of the head circumference, and after 6 months, due to the gradual ossification of the skull, the anterior fontanel will gradually become smaller.

* Usually when the baby reaches 1-1 year and a half, the front fontanel is basically closed.

* The back fontanel is very small, which is generally not noticeable. Most of them are closed 2-3 months after the baby is born.

Abnormal development of fontanel in infants

Folding fontanel bulge

* The front fontanelle was originally flat. If you suddenly bulge, especially when the baby is crying, you feel nervous with your hands, accompanied by fever, vomiting and even convulsions, indicating that the baby's intracranial pressure is increased. Increased intracranial pressure is usually caused by intracranial infection, and the baby may suffer from meningitis, encephalitis and other diseases.

* If the baby's front fontanel gradually becomes full, it may be that there is a tumor in the brain, or there is effusion, pus and hematocele under the subdural space.

* Long-term use of large doses of cod liver oil, vitamin A or tetracycline can make the baby's front fontanel full. However, after vitamin A and tetracycline are stopped, the anterior fontanel will gradually flatten out.

* For some reason, the baby was injected with adrenaline. If you stop taking medicine suddenly, you can also make your baby's front fontanel full.

Folding fontanel depression

* fontanel depression, more common in the baby's lack of water. If you don't replenish water in time after diarrhea, the front fontanel is sunken. In this case, the baby needs to be replenished with liquid immediately.

* In order to reduce intracranial pressure, a large dose of dehydrating agent was used, and dehydration caused anterior fontanel prolapse. It is necessary to replenish water to the baby's body in time to prevent excessive dehydration from causing metabolic disorders in the body.

* Malnourished and emaciated babies usually have sunken front fontanels.

Early closure of folding fontanel

* When the fontanel of a baby is closed earlier, the size of its head circumference must be measured. If the head circumference is lower than normal, it may be brain dysplasia.

* Some healthy babies, at the age of 5-6 months, the front fontanel is only the size of a fingertip, which seems to be closing, but it is not ossified, so they need to be identified by a doctor.

Closing delay of folding fontanelle

* The fontanel is closed late, which mainly means that the baby has passed 18 months, but the front fontanel has not been closed, which is more common in rickets and minor illnesses.

* fontanel closed late, and a few cases were caused by hydrocephalus or other reasons, so they should go to the hospital for further examination.

The folding fontanel is too big.

* The fontanel is too large, which generally means that the fontanel will reach 4-5cm shortly after the baby is born.

* fontanelle is too big. One is that the baby may have congenital hydrocephalus, and the other is that it may be caused by congenital rickets.

* When a baby with congenital hydrocephalus is born, his head is squeezed when he passes through the birth canal, so his fontanel is not big at birth. But a few days after birth, the front fontanel usually gets bigger and bigger.

* After the baby with congenital rickets is born, not only the front fontanel is big, but also the back fontanel, and a bone seam (sagittal seam) in the middle is also wide, connecting the front fontanel and the back fontanel.

The folding fontanel is too small.

* fontanelle is too small, which mainly means fontanelle is only as big as a fingertip. Such babies are likely to have microcephaly.

* The fontanel is too small, which may also be caused by premature closure of the skull, especially the premature closure of sagittal suture, which will make the baby's skull longer and narrower, forming a skull called navicular deformity, that is, the occipital part is prominent, the forehead is wide, and the front fontanel is small or invisible.

* When the baby is too young, it is necessary to measure the head circumference regularly, that is, to observe whether the head circumference is within the normal range before the full moon.

* Check the growth rate of head circumference every month or every two months, and compare it with normal infants to see if there is obvious backwardness.

* If after 3-4 months of follow-up, the baby's head circumference development is still normal and can be maintained, even if the fontanel is small, it will not affect the development of the brain.

Fold and clean fontanelle correctly.

Brain tissue is as soft as tender tofu and needs the protection of bone skull. The skull is closed, and the fontanel is an open gap above, which is easily influenced by external unfavorable factors.

It is what parents want to do to do a good job of nursing the fontanel, protect the normal development of the baby's brain and let the child grow up intelligently.

Since ancient times, people have known to use hair to protect fontanel. When a baby shaves his head, he keeps the hair at the fontanel to protect the fontanel, which looks like an iron shovel for cooking. Some areas in China are called "spatula heads", forming a landscape where babies have "spatula heads". The three locks of "San Mao" written by Mr. Zhang Leping are the three hairs that protect the mouth.

Some parents don't know much about fontanelle, and they dare not touch it or clean it, which leads to dirt accumulation. Moreover, because babies are prone to seborrheic eczema (commonly known as tinea lactis), greasy scales and dirt can easily be mixed into ugly "shit bumps" full of fontanels. All these are beneficial to the parasitism of some pathogenic microorganisms, which are easy to cause scalp infection, and then the pathogens penetrate the fontanel without bone structure and cause meningitis and encephalitis, so the clean nursing of fontanel is more important.

You can clean the fontanel when taking a bath, and you can use a special shampoo for children instead of strong alkali soap to avoid stimulating the scalp to induce eczema or aggravate eczema. When cleaning, your fingers should be placed flat at the fontanel, and rubbed gently. You can't press or scratch hard, and you can't scratch at the fontanel with sharp tools. If the "shit bumps" at the fontanel are not easy to wash off, you can steam them with sesame oil or refined oil and soak them for 2 ~ 3 hours. When the dirt becomes soft, wipe it off with a sterile cotton ball in the direction of hair growth, and then wash it with baby powder. If you accidentally scratch your scalp, you should immediately disinfect it with an alcohol cotton ball to prevent infection.

Usually pay attention to avoid sharp things stabbing the fontanel, and wear a hat when carrying the baby out. Wear a thick hat when going out in winter to protect your head and reduce heat loss; Wear a white cool hat when going out in hot summer to protect the fontanel. With the popularization of parenting knowledge, parents all know that taking their babies outdoors 1 ~ 2 hours to avoid light can prevent rickets. Please pay attention to basking in the sun after morning and before dusk, and don't direct the scorching sun at the fontanelle to avoid heatstroke.