central pontine myelinolysis
Introduction
Introduction to central medullary myelinolysis Central ponsine myelinolysis (CPM) is a fatal disease characterized by symmetry demyelination at the base of the pons. This disease is a rare acute myelinolysis lesion, which is now considered to be low. Sodiumemia, specifically due to the rapid correction of hyponatremia. Adams et al. (1959) first reported that the first case of Adams et al. in 1950 observed a young chronic alcoholism, hospitalized for alcohol withdrawal symptoms, developed into quadriplegia and pseudobulbaric paralysis within a few days, and very Coming soon. The main finding of the pathological examination is a large area of symmetry demyelinating lesions at the base of the pons, which is known by its name. basic knowledge The proportion of illness: 0.001% - 0.008% Susceptible people: no special people Mode of infection: non-infectious Complications: urinary tract infections acne
Cause
Causes of central myelinolysis in pons
(1) Causes of the disease
In the early cases, most of the patients were found to be patients with severe or chronic wasting diseases, especially malnourished chronic alcoholism, and most of them coexisted with Wernicke encephalopathy. Therefore, the incidence is related to malnutrition, but in some cases, it is difficult to find Malnutrition factors exist.
Most authors now believe that the cause of this disease is caused by hyponatremia and excessive or excessive correction of hyponatremia. When hyponatremia occurs, the brain tissue is in a hypotonic state, and hypertonic saline is supplemented too quickly. Sodiumemia causes a rapid increase in plasma osmotic pressure, causing dehydration of brain tissue and destruction of the blood-cerebrospinal fluid barrier. Harmful substances can cause loss of myelin through the blood-cerebrospinal fluid barrier.
(two) pathogenesis
Severe hyponatremia (blood sodium at least below 130 meq/L, mostly lower) is present in almost all reported cases (Adams et al, 1959; Burcar et al, 1977; Karp et al, 1993).
In animal experiments, repeated injections of angiotensin (visopressin) and intraperitoneal injection of water caused severe hyponatremia (100-115 meq/L), followed by injection of hypertonic saline (3%) to correct hyponatremia and The presence of severe weakness, followed by the emergence of tonic quadriplegia in these dogs, its pathological changes are almost indistinguishable from human central bridge myelinolysis (Laureno, 1983), but McKee et al (1988) reported that in the necropsy Ten of the 139 severely burned patients had typical central demyelinating lesions of the pons. According to histological features and clinical data, when the 10 burn patients with cerebral central myelinolysis had pons, clinical There have been severe, persistent hyperosmolarities without hyponatremia; no hypernatremia, hyperglycemia or hyperazoemia.
The most striking feature of this disease is its pathological anatomical changes. The central gray of the pons of the pons is visible in the horizontal section of the brainstem, which is a fine-grained lesion. The lesion can range from a few millimeters in diameter to occupy almost the entire pons, but in the lesion There is always a circle of normal myelin between the surface of the pons. The lesion can be from the back to the medial collateral. When it is very serious, it can be extended to other covered structures. In rare cases, the lesion can be extended to the midbrain, but it has never been involved. Medulla, in cases of severe cerebral palsy, sometimes in the thalamus, hypothalamus, striatum, internal sac, deep cerebral cortex and similar white matter found similar to pons lesions, symmetrically distributed demyelinating area, called For extrathoracic myelinolysis.
The most basic feature of the lesion under the microscope is the destruction of the myelin sheath in the affected area and the relatively intact axon and bridging nerve cells. The lesion always starts from the center of the pons and the most severe part of the lesion is here, sometimes developing into obvious tissue. Necrosis, reactive phagocytic cells and glial cells are seen in the demyelinated area, but no oligodendrocytes, and it is noticeable that there is no other inflammatory reaction in the lesion.
The current consensus on this disease is that some areas of the brain, especially the base of the pons, have a special susceptibility to certain metabolic disorders that cause central demyelination of the pons, which may be either rapidly or excessively corrected. Sodiumemia may also be severe hyperosmolaremia.
Prevention
Central bridge myelinolysis prevention
There is no effective prevention method, and prevention and treatment of primary disease and complications are important contents of clinical medical care.
Complication
Pulmonary central myelinolysis complications Complications, urinary tract infection, acne
As the disease progresses, the symptoms and signs that appear may be the primary disease manifestations. In addition, secondary lung infections, urinary tract infections, hemorrhoids, etc. should be noted.
Symptom
Pneumonia central myelinolysis symptoms common symptoms cachexia hyponatremia liver failure pseudobulbar paralysis bacterial infection renal failure quadriplegia dehydration
1. The disease is sporadic, can occur at any age, and child cases are not uncommon. The prominent feature of this disease is that the patient is in the late stage of chronic alcoholism or often accompanied by a serious life-threatening disease.
More than half of the cases occur in the later stages of chronic alcoholism, accompanied by Wernicke encephalopathy and multiple peripheral neuritis, and other diseases or clinical symptoms often associated with central medullary myelinolysis: dialysis treatment Chronic renal failure; liver failure; advanced lymphoma and cancer; cachexia caused by various causes; severe bacterial infection; dehydration and electrolyte imbalance; severe burns and hemorrhagic pancreatitis.
2. Only a small number of patients, the central medullary myelinolysis can be diagnosed before birth, patients often on the basis of the primary disease, sudden limb flaccid paralysis, chewing, swallowing and speech disorders, nystagmus and eye gaze disorders, etc., can be silent And complete or incomplete atresia syndrome.
3. Brainstem auditory evoked potential (BAEP) can help to determine the pons lesions, but the extent of the lesion can not be determined. MRI can find the characteristic bat wing-like lesions in the basal part of the pons, showing a symmetric distribution of T1 low signal, T2 high signal, no enhancement effect. .
Examine
Examination of central medullary myelinolysis
1. Peripheral blood leukocytosis, erythrocyte sedimentation rate.
2. Cerebrospinal fluid pressure is increased or normal, the number of cells increases, and the protein is mild to moderately elevated.
3. Imaging examination, especially MRI examination, greatly improved the prenatal diagnosis rate of central medullary myelinolysis. The typical batwing lesions found at the base of the pons found by MRI have diagnostic significance, but this change is only clinical. Symptoms can take place only a few days later.
4. Brainstem auditory evoked potential examination is helpful for lesions involving the pons of the pons.
Diagnosis
Diagnosis and identification of central myelinolysis in pons
Patients with chronic alcoholism, severe systemic diseases and hyponatremia corrected too quickly, clinically developed into quadriplegia within a few days, pseudobulbaric palsy and atresia syndrome, should consider the central medullary lysis of the pons Diagnosis of the disease, MRI helps to confirm the diagnosis.
The disease should be differentiated from cerebral infarction, tumor and multiple sclerosis. MRI showed that CPM had no significant space-occupying effect, the lesion was symmetrical, and it did not conform to the characteristics of blood vessel distribution, and it could return to normal as the condition improved.
