Clinical staging and segmental localization diagnosis of intravertebral canal tumor 1. Clinical staging of intravertebral canal tumor Clinical manifestations due to the progressive compression of the tumor and damage to the spinal cord and nerve roots, its clinical manifestations can be divided into three phases: ① irritation phase, the tumor is small in this phase, and the main manifestation is irritation symptoms of the corresponding structures, the most common symptom in this phase is radicular neuralgia, which is expanding along the root distribution area, and is distributed in the limbs as a thread-like distribution. The most common symptom in this stage is radicular pain, which extends along the radicular distribution area and has a linear distribution in the limbs, and has a band-like distribution in the trunk. It is aggravated by coughing, straining, breath-holding, and defecation. The area of pain is fixed, and some patients may have “night pain” or “lying down pain”, which is one of the characteristic manifestations of intraspinal tumor. ②Partial compression of spinal cord, with the growth of the tumor, the volume increases, the spinal cord is squeezed, and the symptoms of spinal cord conduction bundle compression gradually appear. Typical signs are spinal cord hemisection syndrome (Brown-Sequard’s syndrome), which manifests as ipsilateral upper motor neuron paralysis and loss of tactile deep sensation below the lesion segment, and loss of pain and warmth sensation below the contralateral lesion plane of 2-3 segments. Lesions on the side below the lumbar medulla do not cause this syndrome. In the stage of spinal cord paralysis, the spinal cord hemiparesis syndrome or incomplete paralysis progressively worsens, eventually leading to complete paralysis. There is loss of superficial and deep sensation below the tumor plane, complete paralysis of limbs, autonomic dysfunction such as sphincter dysfunction, and dermal dystrophy. (1) Cervical medulla: manifested as radiating pain in the cervico-occipital region, forced head position, cervical rigidity, spasmodic paralysis of limbs, somatosensory impairment below the lesion segment, phrenic nerve stimulation causing retching and vomiting, phrenic nerve damage resulting in respiratory distress and respiratory muscle paralysis. Cervical bulging lesion may appear neck and shoulder pain, hand muscle atrophy, spinal cord half-cut sign, etc.. (2) Thoracic medulla: radicular symptoms manifest as intercostal neuralgia, abdominal and back pain, sometimes accompanied by band scars, and some patients behave like acute abdomen. The plane of sensory impairment is located below T1 and above the groin, with spastic paralysis of both lower limbs, hyperreflexia of the keys, and hyporeflexia or disappearance of the abdominal wall reflexes. (3) Lumbosacral medulla: upper lumbar segment (L1~3): the medullary joints can not be flexed and the femoral internal retracted movement, the knee, manic and toe are spastic paralyzed. The distribution of radicular pain is in the groin, external hip, perineum or inner thigh. The lower limb cone beam sign was positive, knee reflex was hyperactive, and tiku reflex disappeared. Lower lumbar (L4-5 S1-S2): radicular pain is distributed in the anterolateral thigh or lateral calf, and sensory disturbances are limited to the lower limbs. Knee maniculated joint dyskinesia. Biceps femoris reflex and tic reflex are normal. Knee reflexes and stomp reflexes are absent. Incontinence or retention of urine and feces. (4) Cone (S3-S5): Saddle-shaped hyperalgesia or loss of sensation in the perineum and anal area, called saddle area dysesthesia. There is often bladder and rectum dysfunction, hypogonadism or loss of sexual function. If the tumor compresses the adjacent cauda equina, radicular pain and lower motor neuron paralysis and sensory impairment in one part of the lower limb may occur. (5) Cauda equina: Cauda equina syndrome is often manifested, and pain is the most common early symptom. It is characterized by pain in the lumbar skeleton or sciatica, loss of knee and manic reflexes, and hyperalgesia in the saddle region, which is unilateral in the early stages and then bilateral. Anal reflexes are absent. There may be lower motor neuron paralysis of the lower limbs, sphincter dysfunction appears later, and there may be trophic ulcers on the soles of the feet. Extramedullary subdural tumors Extramedullary subdural tumors account for 60% of intradural tumors, most of which are benign, with nerve sheath tumor, neurofibroma and chordoma being the most common. Most of them are found in 20-60 years old, with typical symptoms of radicular pain and later numbness, aching and swelling or hypesthesia in the limbs. (1) Nerve sheath tumor belongs to benign tumors, the incidence rate accounts for the first place of intraspinal tumors. 30-50 years old is the most common age. Most of them originate from the posterior root of spinal nerve, and some of them develop outside the spinal canal through the intervertebral foramen to become dumbbell-shaped. Pathology: The tumor is round, ovoid or lobulated, often solitary, a few can be multiple, often involving the posterior root of the nerve, so 90% of nerve sheath tumors are located in the posterior and lateral part of the vertebral canal, and the diameter of the tumor is usually only a few centimeters, and sometimes it is easy to develop cystic changes and even hemorrhage. Due to the slow growth of the tumor, the spinal cord is subjected to long-term pressure, and there are obvious pressure marks, even in the form of flat strips, accompanied by edema and softening, etc. The first choice for treatment is surgery. Surgery is the first choice for treatment, and the tumor can be resected completely with few recurrences and good prognosis. (2) The incidence rate of chordoma is the second place of intraspinal tumor, accounting for 25% of all intraspinal tumors. They mainly originate from arachnoid cells, almost all of them are benign, and are the most effective intravertebral tumors for surgical resection. It is more common in females, with 40-60 years old as the most common age, and is more common in thoracic segment (80%), followed by cervical and lumbar segments, and is rare in sacral region. Localized adhesion to the dura mater. Pathology: Spinal meningioma originates from arachnoid cells, more than 80% occur in the thoracic segment, rare in the cervical segment, rare below lumbar 1, usually located in the posterior and lateral part of the spinal canal. The tumor is round or ovoid, without clitoris in broad base shape, mainly solitary, with diameter of 2-3.5cm, and is substantial. Surgery is the first choice for treatment, and attention should be paid to the treatment of affected dura mater during surgical treatment, otherwise there is a possibility of recurrence. (3) Lipoma mostly occurs in the age of 40, mainly manifested as spinal cord compression symptoms, pain appears less and there is no radiating pain. (1) Ventricular meningioma is the most common intramedullary tumor (60%), most of them are slow-growing benign intramedullary tumors, and only a few of them are malignant. Most of them are slow-growing benign intramedullary tumors, and only a few of them are malignant. The tumor has a thin pseudo-envelope on the surface, which forms a boundary with the normal spinal cord tissue. Surgery is the only effective method, the timing and indications for surgery are not uniform, usually with moderate neurological dysfunction as an indication. (2) Astrocytoma is also a common intramedullary tumor, accounting for about 30-40% of all intramedullary tumors. It is the most common intramedullary tumor in children, and it is prevalent at the age of 10-25 years. Most of them are low malignant and have a good prognosis. Most of them are found in the thoracic spinal cord, and MRI scans show localized thickening of the spinal cord, with abnormal signals in between, and some of the lesions may be strengthened. Pathology: The tumor starts from astrocytes of spinal cord, shows expansive or infiltrative growth, and there is no obvious decomposition with normal spinal cord, the tumor may undergo cystic transformation to form cavities (38%), and the cavities may extend upward to the medulla oblongata. The degree of malignancy of spinal cord astrocytoma is lower than that of intracerebral, 76% are grade I-II, but its malignancy is disproportionate to the extent of the tumor. The tumor is infiltrative growth, lack of clear decomposition with normal tissues, surgical resection is easy to cause complications, so it needs to be carefully resected under the microscope or select biopsy plus laminectomy. Extradural tumors Extramedullary epidural tumors account for 25% of intradural tumors, and most of them are malignant tumors, such as metastatic tumor and lymphocytoma, and there are sarcomas, lipomas, hemangiomas, osteomas, chondrosarcomas, nerve sheath tumors and chordomas, etc. The treatment should be surgical and based on pathology. Treatment requires surgery and radiotherapy according to the nature of pathology. (1) Metastatic tumor is most common in the elderly, pain is the most common first symptom, and severe spinal cord compression will soon appear. Thoracic spine is the most common, followed by lumbar spine, cervical spine, sacral spine is rare. Primary tumors are most common in breast, lung and prostate cancers, followed by lymphoma, renal cancer and melanoma. The metastatic pathways are: 1, trans-arterial dissemination; 2, trans-vertebral vein dissemination; 3, trans-lymphatic dissemination; 4, trans-subarachnoid dissemination; 5, direct invasion of neighboring foci into the vertebral canal. Hematogenous metastases are mostly located in the lateral and posterior part of the extraperitoneal space, which can affect the vertebral body and accessories, but the intervertebral disc is not invaded. (2) Lymphoma is mostly seen in male, and the age of onset is not consistent. It often involves thoracolumbar vertebrae and mainly manifests as spinal cord and nerve root compression symptoms, with local pain being the most common, and lower limb motor and sensory disorders and sphincter dysfunction gradually appearing. Malignant lymphoma may invade the intravertebral structures via the lymphatic system, but less frequently involves the vertebral body. The diagnosis of lymphoma often needs to be combined with clinical and laboratory examination for comprehensive judgment. 4.Congenital tumors include epithelioid cyst, dermatoid cyst, teratoma and so on. Epithelioid cysts and dermatoid cysts originate from the ectopic germ layers of the vertebral canal that develop into skin. Epithelioid cysts have translucent walls of complex squamous epithelial tissue with contents of exfoliated keratinized epithelium rich in cholesterol crystals. Dermatoid cysts have thicker walls, more fibrous tissue and dermis at the base of the stratified squamous epithelium, containing skin accessory structures such as sweat glands, sebaceous glands, and hair follicles, and often have hair in the contents. Teratomas are less common and contain tissue originating from all three germ lobes. Surgery is the only treatment option available, with removal of the capsule contents and partial or total excision of the tumor wall, depending on the location and nature of the tumor.