thalamic tumor resection

Thalamic tumors account for about 1% of intracranial tumors. Deep in the brain, the medial and inferior third ventricle and hypothalamus, and the outer sac. If the tumor is resected, such as the important structure around the injury, it will lead to adverse consequences. In thalamic tumors, gliomas account for about 90%. Among all types of gliomas, astrocytoma accounts for about 80%, and other such as oligodendroglioma, mixed glioma and ependymoma account for about 20%. According to Berstein (1984), in astrocytomas, half of the patients with low and high grades are inferior. Before the 1950s, most of them were conservative in the removal of thalamic tumors. Aseni (1958) reported that 10 cases of basal ganglia tumors were treated with surgical resection, and 6 of them survived for 3 to 9 years. In recent years, with the development of microsurgical techniques, the clinical application of ultrasound surgical aspirator (CUSA), the efficacy of thalamic tumor resection has been significantly improved, the surgical disability rate and mortality have decreased significantly, many patients obtained after surgery Survive for a long time. Among a group of 17 gliomas in China, 2 patients with low-grade astrocytoma survived for 14 and 26 years, and their life and work were still good. Treating diseases: glioma Indication Thalamic tumor resection is applicable to: 1. The clinical manifestations are hemiparesis or hemiplegia, unilateral sensory dysfunction and isotropic hemianopia, and more often accompanied by increased intracranial pressure symptoms, confirmed by CT scan or MRI examination for thalamic tumor, the patient can tolerate the operator. 2. The thalamic tumor was stereotactic biopsy, and the pathology proved to be a well-differentiated glioma or other benign tumor. 3. After the thalamic tumor was treated by radiotherapy, the tumor did not shrink significantly. Contraindications 1. Small spherical lesions of the thalamus, the patient has no obvious symptoms, and the nature of the lesion is difficult to determine. Non-surgical treatment such as anti-inflammatory can be performed, and CT examination is performed regularly. According to the reduction or enlargement of the lesion, further treatment measures are decided. 2. Thalamic metastases, multiple lesions in the brain or thalamic tumors were stereotactic biopsy. Pathology confirmed as malignant glioma, surgery is difficult to prolong survival. Preoperative preparation In recent years, due to the use of microsurgical techniques for deep brain tumor resection, surgical microscopes and other microsurgical instruments should be prepared before surgery, and conditional units can also prepare navigation systems. Surgical procedure 1. When the tumor is located in the anterior part of the thalamus, a forehead flap incision is made, and 4 skulls are drilled to form a rectangular bone flap. The dural flap is turned to the sagittal sinus side, in front of the cortical motor area and from the sagittal midline. At each 2.5 cm, the frontal cortex was cut longitudinally 3 cm. 2. When the tumor is located in the posterior part of the thalamus, a one-sided top flap incision is used to form a rectangular skull flap with a dural flap turned to the sagittal sinus side, 2.5 cm from the cortical motor area and the sagittal midline, and the incision is made posteriorly. Leaf cortex 3cm. 3. For the anterior thalamic tumor, the frontal lobes should be cut into the anterior horn of the lateral ventricle; the posterior tumor should be cut into the posterior and triangular regions of the lateral ventricle. Retract the lateral wall of the lateral ventricle, see the lateral ventricle choroid plexus through the interventricular pore into the third ventricle, thalamo-striate vein (thalamo-striate vein) at the posterior edge of the interventricular septum and the transparent septum, into the third ventricle intracerebral vein At this time, it can be seen that it is equivalent to the upper bulge of the tumor. If the tumor has cystic changes, it is feasible to puncture the liquid. Before incision of the thalamus to explore the tumor, the interstitial space in the anterior chamber is covered with a saline pad, and the triangular area and the posterior horn are also padded with cotton pad to prevent intraoperative bleeding and blood from flowing into other parts of the ventricular system. It is best to operate under a surgical microscope. The ependymal and thalamic tissues are dilated by bipolar electrocoagulation at the tumor bulge, and tumors are generally found only a few millimeters. Apply microscopic stripper and small cotton sheet to close the surface of the tumor and peel off normal brain tissue. For example, the tumor is benign or low-grade glioma, and the tumor is completely cut or under the naked eye; if the tumor is high-grade, the tumor When the boundary with the normal brain tissue is unclear, it is not necessary to use barely peeling, and the invasive method of attracting the side of the tumor around the tumor can not be used. When the upper or upper part of the tumor is exposed, the surface of the electrocoagulated tumor is exposed. At the beginning, the tumor-clamping force was strictly entered into the tumor center to remove the tumor content to reduce the tumor volume. Continue to peel away from the surface of the tumor to the deep part, electrocoagulate the tumor blood vessels, and remove the tumor tissue in blocks. The operation must be meticulous and accurate, without damaging the surrounding normal structure, reaching most or subtotal resection of the tumor, or even under the naked eye, with clear or covered tumors, and strive to be fully cut. 4. After the tumor is resected, the tumor bed is hemostasis by bipolar electrocoagulation, clearing the blood clot accumulated in the cerebral ventricle, and then repeatedly flushing the ventricle with a large amount of physiological saline, and a silicone drainage tube is built in the ventricle to prepare the postoperative ventricle. Continuous drainage bottle and intracranial pressure monitoring. 5. The dura mater is tightly sutured, the dura mater is externally drained, the bone flap is repositioned, and the suture is layer by layer. In addition, some authors used the anterior approach of the corpus callosum to enter the lateral ventricle to remove the tumor. Prakash (1986) also entered the lateral ventricle to remove tumors through the parietal lobe, cerebral hemispheres, and the lateral ventricle of the lateral ventricle, but there are currently few applications. complication 1. Intraoperative and postoperative hemorrhage of obstructive or traffic hydrocephalus resection, blood flow to the ventricular system and subarachnoid space, affecting the absorption and circulation of cerebrospinal fluid. Generally, through continuous drainage of the ventricle or repeated lumbar puncture drainage and clot lysis, blood absorption, the condition can be relieved or self-healing. In some patients, conservative therapy is ineffective, and lateral ventricle-cerebellar medullary shunt or ventriculo-peritoneal shunt should be performed in time. 2. Intracranial infections are caused by continuous drainage of the ventricles. Select appropriate antibiotics for the sensitivity of the bacteria to the drug and the passage of the drug through the blood-brain barrier. Such as ceftriaxone sodium (bacteria must cure) 1 ~ 2g, 1 or 2 times a day, soluble in physiological saline, intravenous drip, good effect on Gram-positive and negative bacteria, and easy to pass the blood-brain barrier, is control An effective antibiotic for intracranial infections. With severe intracranial infection, cerebrospinal fluid opacity or purulent, the infection is still difficult to control by systemic and intrathecal antibiotics. At this time, the ventricles and subarachnoid space should be washed. Some authors in China have used cefazolin (Ceramicin No. 5) 0.5g dissolved in 500ml of normal saline, dripped by the lateral ventricle drainage tube, and discharged through the lumbar puncture needle. The rate and amount of entry and discharge are basically equal. This method cures many patients with severe intracranial infection and dying.