spinal cord intramedullary tumor resection

Spinal cord intramedullary tumors account for about 15% to 20% of intraspinal tumors, and are more common in cervical and thoracic spinal canal. Among the intramedullary tumors, there are mainly various types of gliomas, and a few are epithelioid cysts, dermoid cysts, vascular reticuloma and lipomas, and there may be metastases and meningioma. Intramedullary tumors mostly have sensory disturbances as the first symptom. From the point of view of surgical treatment, intramedullary spinal cord tumors can be divided into two types, one is soft invasive tumor, such as malignant astrocytoma, polymorphic colloid. Maternal tumors, such tumors are invasive growth, often liquefaction, necrosis and cystic changes, and there is no clear boundary with normal spinal cord tissue, it is impossible to completely remove; another type of texture is hard and clear with the surrounding spinal cord tissue The boundaries may be completely removed, such as ependymoma, vascular reticuloma, and astrocytoma grade 1 (hair cell type). In intramedullary tumor surgery, the spinal cord must be incised and the tumor separated from it in order to remove the tumor. In general, intramedullary tumors account for about 50% of the cervical spinal cord. Postoperative neurological damage and spinal cord edema can aggravate the existing symptoms, or even respiratory muscle paralysis, central hyperthermia and other complications, so the risk of surgery Sexually large. If microsurgical techniques are applied, surgical damage can be minimized. Treatment of diseases: spinal cord tumors Indication Spinal cord intramedullary tumor resection is suitable for patients with neurological dysfunction diagnosed as intramedullary spinal cord tumor with progressive aggravation. Contraindications The age is upset, the vital organs such as the heart and lungs are poor, and the limbs are completely paralyzed for more than 3 months. Preoperative preparation 1. Prepare microsurgical instruments. 2. The nature of spinal cord intramedullary tumors is difficult to estimate before surgery. The operation is invasive and the total rate of resection is low. Therefore, before surgery, doctors must explain the various possibilities to the relatives of the patients and obtain their understanding and cooperation. Surgical procedure 1, surgical incision and laminectomy The number of surgical incisions and laminectomy was determined based on the length of the tumor displayed by myelography and MRI. After laminectomy, most of the epidural fat disappeared in the lesion, and the dural sac was fusiform, which had a firm feeling. The pulsation was visible above the swelling, while the pulsation disappeared below. The laminectomy must exceed this enlarged area to the extent of normal epidural fat. 2, dural incision After suturing the number of needle pull lines on both sides of the dura mater, the dura mater is cut at the midline of the inflated portion of the spinal cord. It should be noted that sometimes the spinal cord can adhere to the dura mater. Therefore, when the dura mater is cut, a small opening is made at the non-adhesive site of the peritumoral, and then the microscopic peeling is performed. If there is adhesion, the edge is separated or cut. The focus should be on the side of the dura mater. It is not advisable to do a one-time incision of the dura mater, as this may cause spinal cord injury. The spinal cord segment where the intramedullary tumor is located is fusiform, and the tumor is often invisible on the surface of the spinal cord, but may be pale yellow or brownish purple, and the blood vessels on the surface of the spinal cord may be indeterminate. Sometimes extramedullary tumors located in the ventral side of the spinal cord can cause the spinal cord to bulge to the dorsal side and are mistaken for intramedullary tumors. In particular, those who have not undergone MRI examinations must carefully explore the spinal cord before making a diagnostic puncture to eliminate this possibility and then puncture. 3, tumor resection Because of the different nature of the tumor, there are also differences in the method of resection. The resection process of the main intramedullary spinal cord tumor is now described as follows: (1) Astrocytoma: This tumor accounts for about 30% of intramedullary tumors. There is a clear boundary between grade I astrocytoma and adjacent spinal cord tissue, which is composed of proliferating glial cells and small blood vessels, and some astrocytomas may have cystic changes. Malignant astrocytoma and glioblastoma multiforme are rich in blood vessels, often with hemorrhage and necrosis, and the boundary between adjacent spinal cord tissue is unclear, and some tumors even protrude from the surface of the spinal cord. The specific surgical method for astrocytoma is as follows: the cystic tumor is first placed in the dorsal side of the spinal cord without a blood vessel, and the needle is inserted into the spinal cord with a 22-gauge needle. The depth should not exceed 5 mm, because the astrocytoma is mostly located. The dorsal spinal cord is a few millimeters below the subdural, and a yellow or orange-red liquid can be drawn into the capsule. If it is a solid tumor, it can be cut in the medial side of the spinal cord or close to the superficial midline of the tumor. If the tumor is soft and the spinal cord has no clear boundary, the invasive growth is highly classified III, IV. Grade astrocytoma can only be removed from the tumor or partially removed, and the effect of decompression is obtained. If the tumor is hard and has a clear boundary with the surrounding spinal cord tissue, mostly astrocytoma grade I or II, microsurgery can be used for total resection, and the resection method is the same as ependymoma. (2) ependymoma: This tumor is more common in intramedullary tumors, occurs in the thoracic spinal cord, can also be seen in the cervical and conical parts of the spinal cord, esophageal tumors in the conical region can be invaded by the spinal cord And cauda equina nerve roots. Ependymoma is mostly well-differentiated, with pseudo-enveloped, dilated, mostly elliptical, less blood vessels, blood supply from the ventral and median blood vessels of the spinal cord, sometimes with cysts, tumors and surrounding The spinal cord has obvious boundaries. After the surgical exploration has identified that it may be an ependymoma, it is advisable to use a microsurgical procedure to perform an operation 6 to 10 times in the field. Generally, a median incision is made on the dorsal side of the spinal cord or longitudinally in the median side of the tumor surface. The spinal cord is separated by a microscopic stripper to reveal the surface of the tumor. The tumor may be reddish or taupe. When the tumor and the spinal cord are separated, the focus of the instrument should be on the side of the tumor. Try not to touch the spinal cord, use a microscopic aspirator, and adjust the suction force. The power of the bipolar coagulator should also be reduced. Take the snake brand bipolar coagulator as an example, the output power can be adjusted to 1, 5 to 1, 8 readings. The end of the tumor is first released, where several perforating sutures are made, through which the tumor is lifted and further separated along the edge of the tumor. Some of the spinal cord intramedullary ependymoma is often very fragile and easily torn in the separation, but there is always a boundary between the spinal cord and the tumor parenchyma, patiently and carefully separated until the tumor is completely removed. Generally speaking, there is always one pole in the two poles of the tumor that is relatively easy to free. At this time, the tumor can be separated from the end which is easy to free, and then penetrate through several thick wires to make the tumor for traction, and continue to the end of adhesion and fibrosis. Separation, such an operation is beneficial to the tumor from the tumor bed, revealing tumor blood vessels in front of the surgical field, facilitating electrocoagulation and cutting. If the interface between the tumor and the spinal cord is found to be unclear during the process of tumor isolation, the separation should be stopped immediately, and only the part of the tumor that has been isolated is removed. Failure to do so will result in increased spinal cord damage. (3) Subependymoma: This tumor contains a dense fibrous matrix because histopathology is different from that of ependymoma. Therefore, WHO tumor classification classifies it as a new type. It occurs mostly in the cervical and thoracic segments of the spinal cord and is eccentrically growing, which is distinct from the spinal cord. Separation under the microscope can reduce the damage of the surgery. (4) Vascular reticuloma (hepatoblastoma): a relatively rare benign tumor in intramedullary tumors, which may be located entirely within the spinal cord or partially protruding from the surface of the spinal cord. This tumor can occur in various segments of the spinal cord. Because the blood vessels are rich, mostly meat red, spinal angiography before surgery, will provide a reference for the diagnosis and surgery of this disease. This tumor has a complete envelope, mostly substantial, sometimes cystic. The surgical resection method is similar to the ependymoma. Under the operating microscope, the tumor supply artery can be released for a short period of time by careful separation. After bipolar electrocoagulation treatment and cutting, the tumor can be completely removed. To reduce intraoperative bleeding, it is necessary to emphasize that tumor resection should not be performed. Because of the bleeding in the section, it is difficult to stop bleeding and it is easy to damage the spinal cord. (5) Lipoma: It often invades into the spinal cord in a lobulated shape, and there are nerve fibers in the tumor tissue. Therefore, this intramedullary tumor is difficult to be resected. In order not to damage the spinal cord, only the tumor tissue can be partially removed and decompressed. The laser can help. For resection. Previous use of secondary surgery for intramedullary spinal cord tumors. That is, after the first operation is determined as the intramedullary spinal cord tumor, only the midline incision of the dorsal side of the spinal cord is performed, so that the tumor can be self-extracted from the spinal cord. At this time, a silicone membrane can be used to cover the spinal cord and the bilateral dorsal sphincter. The cutting edge is stitched. The incision was reopened during the second operation, and the silicone membrane was taken out, and the tumor removed from the spinal cord was excised. This method is currently rarely used in the context of the development of microsurgery. 4, incision suture After partial or total resection of the intramedullary spinal cord tumor, the surgical field completely stops bleeding. For the complete resection of the tumor, the dura mater can be tightly sutured. The dura mater can be opened and decompressed, and the edge is sutured around. Muscle, muscle, deep fascia, subcutaneous tissue, skin layered suture. complication 1. Epidural hematoma Paravertebral muscles, vertebrae and epidural venous plexus are not completely hemostasis. Hematoma can form after operation, resulting in increased limb spasm, which occurs within 72 hours after surgery. A hematoma can occur even when the drainage tube is placed. If this phenomenon occurs, it should be actively checked to remove the hematoma and completely stop bleeding. 2, spinal cord edema Often caused by surgical operation to damage the spinal cord, the clinical manifestations resemble hematoma. The treatment is mainly dehydration and hormones; in severe cases, the dura mater has been sutured, and the operation can be performed again to open the dura mater. 3, cerebrospinal fluid leakage It is caused by lax suture of the dura mater and/or muscle layer. If there is drainage, it should be removed in advance. If the leakage is less, the dressing is observed. If it cannot be stopped or the fluid is leaked, the leak should be sutured in the operating room. 4, wound infection, splitting The general condition is poor, and the incision healing ability is poor or the cerebrospinal fluid leakage is easy to occur. Intraoperative attention should be paid to aseptic operation. In addition to antibiotic treatment, it should actively improve the general condition, paying special attention to the supplement of protein and multivitamins. Special parts such as between the shoulder blades should be reinforced with muscle layer sutures. 5, intraoperative spinal cord injury caused by increased dysfunction.