What Is the Connection Between the Midbrain and the Pons?

Also known as the pons, is part of the brainstem. It is located between the medulla oblongata and the midbrain. The ventral area of the pontine is the base of the pontine, which contains a large number of transverse fibers that connect the cerebellar hemisphere, and also some longitudinal nerve fibers.

Also known as the pons, is part of the brainstem. It is located between the medulla oblongata and the midbrain. The ventral area of the pontine is the base of the pontine, which contains a large number of transverse fibers that connect the cerebellar hemisphere, and also some longitudinal nerve fibers.

Chinese name

Pontine

Foreign name

pons

location

Above the medulla oblongata

Physiological function

Adjust breathing

Pinyin

Nao Qiao

Pontine anatomy

The pontine is located between the midbrain and the medulla oblongata and is divided into the ventral basal part and the dorsal cover part.

The ventral side of the pontine is broad and swollen, which is called the pontine base. Its upper edge is connected to the cerebral feet of the midbrain; the lower edge is continuous with the medulla by the pons. Inside the pons and medullary sulcus, abdomen nerve, facial nerve and vestibular snail nerve roots emerge from the brain in order from the inside to the outside. There is a longitudinal shallow groove in the middle of the ventral side, called the basal sulcus, which houses the basilar artery. There are a large number of transverse fibers on the ventral side, which gradually narrow to the sides, move to the cerebellum or the pontine, and turn to the dorsal side to enter the cerebellum. A large trigeminal root is attached at the transition, and this root is usually regarded as the dividing line between the ventral side of the pontine and the midfoot of the cerebellum. The base of the pontine is a relay station connecting the large and small cerebral cortex.

The intersection of the medulla oblongata and the posterior cerebellum is clinically called the pontine cerebellar triangle. The vestibular snail nerve is located here, which has important clinical significance. When a tumor compresses the vestibular snail nerve fibers there, hearing impairment and cerebellar damage may occur. At the same time, the tumor can also compress the facial nerve, trigeminal nerve, glossopharyngeal nerve, and vagus nerve, resulting in corresponding symptoms. The front end of the pontine is narrow, which is the transition part of the pontine and midbrain. It is called Lingnao Gorge. Here you can see the left and right cerebellum upper feet, or combined arms, moving from the cerebellum forward and downward. There is a premedullary sail between the left and right binding arms. After the cross of the pulley nerve within the premedullary sail, the brain exits the brain on both sides of the midline, bypasses the brain feet after exiting the brain, and reaches the ventral side of the brain stem. The pulley nerve is the only pair of nerves that exit the brain from the back of the brain stem.

There are trigeminal nerves, abductor nerves, facial nerves, and vestibular snail nerves that enter and exit the pontine. The trigeminal nerve root enters and exits the pontine at the junction of the base of the pontine and the midfoot of the cerebellum, and the roots of the abductor nerve, facial nerve, and vestibular snail nerve are located in the medullary pontine groove from the inside to the outside. The abductor nerve is on the inside, 4 to 5 cm from the midline, and the vestibular snail nerve is on the outermost side, just at the pontine cerebellum triangle. The facial nerve is on the inner side of the vestibular snail nerve, and there is a small intermediate nerve between it and the vestibular snail nerve.

Pontine pontine hemorrhage

Sudden onset, severe headache, dizziness, vomiting, falling to the ground, and loss of consciousness within minutes, into a deep coma. Bleeding often starts from one side of the pontine and manifests as cross paralysis, that is, bleeding from lateral paralysis and contralateral flaccid paralysis of the upper and lower limbs. The head and eyes turned to the non-bleeding side, showing a "gaze paralysis". A small number (about 20%) of patients can be limited to such small-scale bleeding; most of them quickly spread to the contralateral side, paralysis of both sides of the face and limbs occurs, bilateral pathological signs are positive, and the head and eyes return to the middle. The lateral pupil is extremely narrow and needle-like (this is a characteristic manifestation, which is caused by damage to sympathetic nerve fibers in the pontine); often persistent high fever, and can affect the medullary respiratory center and early difficulty in breathing. The critically ill patients soon developed irregular breathing, blood pressure decreased, bilateral pupils dilated, light reflection disappeared, and mortality was high.

Points of diagnosis for pontine hemorrhage:

1) Middle-aged and elderly patients with acute onset, rapid disease progression, and risk factors for cerebrovascular disease, such as hypertension and atherosclerosis;

2) Characteristic clinical manifestations of severe pontine hemorrhage: disturbance of consciousness, central high fever, respiratory disturbance, quadriplegia or cross paralysis, pinpoint pupil reduction, ocular bobbing, etc. may occur at the onset and within 24 hours. Complex and complicated with complications such as stress-induced gastrointestinal bleeding, infection, and multiple organ failure;

3) The diagnosis depends mainly on imaging examinations, such as brain CT and MRI. The bleeding site and bleeding volume are the main factors affecting the prognosis.