Neurofibromas

Introduction to neurofibroma Neurofibromas are also known as meningioma, neuroma, perineural fibroids, Schwann cell tumors, and perineural fibroblastoma. The disease has a wide range of names, reflecting different views on its source. It can be summarized in the following categories: the first category: neuroma or Schwannoma; the second category: neurofibromatosis or perihematoblastoma, It refers to connective tissue in which tumor cells are deepened from the inner mesoderm. Neurofibromas can originate from peripheral nerves, cranial nerves, and sympathetic nerves. The tumor is often located in the upper jaw, the quality is soft, the eyelids are swollen and thickened, the pigmentation is sag, the sag is drooping, and the cord and small nodules can be touched without pain. Often associated with glaucoma, iris, ciliary body and choroidal neurofibromatosis. Due to the disease, the defect of the tibia can cause the pulsatile eyeball to protrude or sag and be consistent with the radial artery. If the tumor originates in the muscle cone, visual impairment may occur in addition to the protrusion of the eyeball. basic knowledge The proportion of illness: the probability of being sick over 18 years old is 0.02% Susceptible people: no special people Mode of infection: non-infectious Complications: cutaneous fibroma

Cause of neurofibromatosis

Cause of the disease (60%):

The NFI genome spans 350Kb, has a cDNA length of 11Kb, contains 59 exons and encodes 2818 amino acids, and constitutes 327kD of neurofibroprotein, which is distributed in neurons. The NFI gene is a tumor suppressor gene that causes disease loss due to loss of tumor suppressor function when translocation, deletion, rearrangement or point mutation occurs. Mutations in the NFII gene result in Schwann cell tumors and meninges.

Pathogenesis (35%):

The pathogenesis of this disease is unknown, and may be abnormal development of neural crest. It is thought that it is too much or too high in the production of nerve growth factor, which causes abnormal proliferation of nerve fibers and leads to tumor growth.

The main pathological features are dysplasia of ectodermal nerve tissue, hyperplasia and tumor formation. NFI neurofibromatosis occurs in the distal nerve of the peripheral nerve, the spinal nerve root, especially the cauda equina; the cranial nerve is more common in the auditory nerve, optic nerve and bifurcation nerve. Intraspinal tumors include ependymoma and astroglioma, the most common intracranial tumors are gliomas, tumors vary in size, and the cells are arranged in a nucleus like a fence.

Electron microscopy showed that these tumors were formed by the proliferation of Schwann cells from fibroblasts or peripheral nerves. Tumors are usually benign and grow slowly. About 3% to 4% can cause malignant transformation, especially large plexiform neuroma is more malignant. Most of the malignant changes are peripheral tumors, and the central tumors rarely have malignant changes. Skin fibroids and fibroids are formed by fibrous tissue hyperplasia. Mostly located in the dermis or subcutaneous tissue, no cell membrane, skin pigmentation spots caused by melanin deposition in the epidermal basal cell layer.

NFII is more common in bilateral acoustic neuroma and multiple meningioma. The tumor cells are loosely arranged and common megakaryocytes. In addition, the disease may also have meningeal bulging, syringomyelia, and congenital malformations and other diseases. Some patients still have lesions other than the nervous system, such as metabolic bone disease caused by bone hyperplasia, cranial occlusion, bone replacement due to normal bone replaced by fibroblasts and fibroblasts, cyst formation; and congenital Spinal abnormalities, bone cysts, humeral pseudoarthrosis; may also have a limb and half of the tongue or face hypertrophy, scoliosis and so on. There are also reports of cerebral cortical histology abnormalities, gray matter ectopic islands and localized gliosis, which may be the cause of mental retardation.

Neurofibroma prevention

Prevention common sense:

Conduct genetic counseling. Preventive measures include avoiding the marriage of close relatives, genetic testing of carriers, prenatal diagnosis and selective abortion to prevent the birth of the child. Early diagnosis and treatment of the sprinkler can prolong survival.

Neurofibromatosis complications Complications cutaneous fibroma

The disease can be aggravated, and as the tumor grows, depending on the location of the tumor, corresponding complications will occur.

Symptoms of neurofibromatosis Common symptoms Limb numbness, hypersensitivity, catecholamine secretion

1. Located in the limb mass, it is fusiform, and its nerves often have numbness, pain, and hyperesthesia on the far side of the inner limb.

2. Compression of the tumor can also cause numbness.

Neurofibromatosis examination

When the examination showed that the tumor was pink or grayish white, the base was not easy to move or pedicled, and the quality was hard. It was confirmed by pathological examination.

X-ray plain films can be seen in various skeletal deformities; central nervous system tumors can be found by angiography, CT and MRI. Brainstem auditory evoked potential has a great diagnostic value for acoustic neuroma. Genetic analysis can determine NFI and NFII types.

Diagnosis and diagnosis of neurofibromatosis

Diagnose based on

1. Most of the tumors are located in the limbs, armpits, and can also be located on the clavicle, neck and other parts.

2. The tumor on the limb is completely fusiform, and the limbs innervated by the nerve trunk often have numbness, pain, and hyperesthesia.

3. Compression of the tumor can also cause numbness.

Differential diagnosis

Facial nerve tumors have different clinical manifestations due to their different growth sites. Early symptoms are concealed and clinically misdiagnosed. The clinical manifestations of cerebellopontine angles are similar to acoustic neuromas. It occurs in the humerus and appears as sudden facial paralysis. Bell's palsy, the most common symptom of facial schwannomas is progressive facial dysfunction, and facial muscle spasm can be the first symptom. It should be distinguished from primary facial muscle spasm. Primary facial spasm is rarely associated with facial paralysis. Many scholars have suggested that tumors and other possibilities should be considered if conservative treatment is not improved for 16 to 20 weeks. If the facial paralysis is more than 6 to 12 weeks from the beginning to the full sputum, Bell's palsy, sensorineural deafness, dizziness, unilaterality may be ruled out. Tinnitus may be located in the cerebral cerebral horn, the clinical symptoms of the internal auditory canal. For those with the above clinical symptoms, ear neurology, facial nerve electrophysiology test, facial nerve function localization and other tests should be performed.

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