Clinical data of 1
There were 23 cases in this group, including male 12 and female 1 1, aged from 7 to 64 years. There were 6 pituitary ACTH microadenomas, 4 pineal tumors, 65,438+0 astrocytomas in medulla oblongata, 4 intramedullary and extramedullary tumors in high neck, 65,438+0 meningiomas in parasagittal sinus and sphenoid ridge, 2 gliomas in the fourth ventricle, 2 acoustic neuromas, 65,438+0 ependymomas in lateral ventricle, and sellar region.
2 surgical methods
After general anesthesia, the patient took a sitting position, fixed his head with a hood, cut the skin, subcutaneous and muscular layers, cut the dura mater, cut the cortex and tumor capsule (low power density, wide beam) through the arachnoid plane, and cut off the tumor vaporization with a large spot or focused beam wedge; Focused beam, low power (1 ~ 3W) and short pulse (0. 1 ~ 0.5s) were used to separate residual tumors attached to nerve roots and important blood vessels. The low-energy beam vaporizes the residual tumor mass adhering to or invading the dura mater. After tumor resection, stop bleeding completely, rinse the residual tissue with normal saline, suture the dura mater, restore the bone flap and suture the skin.
Three results
Total resection was performed in 20 cases, and there were no neurological complications after operation. Hemiplegia, aphasia, cerebral palsy (dysphagia) and other original nervous system diseases have been significantly improved. Subtotal resection was performed in 3 cases, and symptoms and signs improved in 2 cases. 1 case died of infection caused by other reasons after pinealectomy. Follow-up ranged from 6 to 65438 08 months, with an average of 65438 02 months. There was no recurrence after the patient returned to work.
4 surgical cooperation
4. 1 preoperative material preparation
① OPMILAS CO2-L (OPTON) consists of a laser generator, a light guide joint arm, a console and a micro-manipulator. Manipulator is an important connecting device between laser instrument and surgical microscope, and laser is refracted to the target structure through manipulator. Adjust the laser focal length (five steps of 200, 250, 300, 350 and 400 mm) before operation, which is consistent with the focal length of the microscope objective; Check the distance between the emission points of CO2 laser and He-Ne laser, and the error should be less than 0.5 mm Check whether the functions of manual control panel and trimmer are in good condition. ② Connect the objective lens of the operation microscope (OPM 1-6, OPTON) with the micromanipulator. Fumigating with 40% formaldehyde for 65438±02h before operation. ③ Prepare conventional neurosurgical instruments, sterile saline 1 000 ~ 2 000 ml, irrigator, brain cotton pad, 15A (three-phase) socket wiring board and automatic negative pressure suction device.
4.2 Patient preparation
After the patient enters the operating room, check the situation of gastric tube and urinary tube, and explain the methods and advantages of the operation to the patient. After general anesthesia, the body position should be adjusted slowly, from supine position to sitting position, and it is appropriate to complete it in about 20 minutes. When the back plate of the operating table rises 15, pay attention to the changes of the patient's blood pressure and pulse. Establish venous access to ensure fluid infusion, drug administration and blood transfusion during operation. Adjust the infusion speed at any time, generally controlled at 20 ~ 40 gtt/min. Intravenous drip of antibiotics during scalp incision can effectively prevent and treat surgical infection.
4.3 Keep the surgical field of vision clear.
Closely observe the progress of the operation, suck out the vaporized smoke in time, and wash it with normal saline to reduce the local temperature. Because the penetration of CO2 laser into tissues is weak, the operating field must be kept clear and clean, and cerebrospinal fluid, physiological saline or blood should be cleaned in time to avoid reducing the laser power and affecting the accuracy of cutting, separating and vaporizing tissues.
4.4 Strictly implement the operation procedures.
Pay close attention to the operation and strictly grasp the technical parameters. When cutting cortex, spinal cord and brain stem parenchyma, the power density is more than 2 500 W/cm2, and the focused light spot (diameter 0. 1 ~ 0.3 mm) is used, and each exposure is less than 0.5 s; ; When the tumor was vaporized, the power density was > > 2 500 W/cm2, and continuous exposure was performed with positive defocus and wide spot (diameter > > 2 mm). Low power, power density of 500 W/cm2, negative defocus (no damage to surrounding structures), medium spot (diameter of 0.3~2 mm), spot diameter larger than blood vessel diameter, total exposure time of 0.5 s ... For important functional tissue laser, exposure time is less than < 0.5 s to prevent heat energy from spreading to deep layer. So that the joystick for adjusting and controlling the laser beam is in a semi-locked state. The operation should be accurate to prevent accidents caused by misoperation and misfire. There were 1 cases of brain stem fire in this group. Because the exposure time of single pulse is only 0. 1 s and the disappearance length of CO2 laser is 0.3 m, the damage is superficial and will not cause dysfunction.
4.5 Prevention of radiation injury
Laser can be refracted from metal instruments in the field of vision to important functional structures nearby. Therefore, bright instruments should be covered with wet cotton sheets to avoid reflecting light and shooting normal tissues by mistake; Great blood vessels and cranial nerves should also be covered with wet cotton sheets for protection. Patients' eyes should be covered with wet blindfolds or wear protective glasses, and staff should also wear protective glasses.
4.6 closely observe the changes of the disease.
The changes of blood pressure and intracranial pressure were observed. High blood pressure may lead to wound bleeding, while low blood pressure may lead to air embolism (vein) in the patient's body (sitting position). Oxygen saturation is controlled above 95%. Strictly carry out aseptic operation.
5 instrument maintenance
Microscopic CO2 laser instrument and microscope are both precision instruments. After operation, the blood and dirt were wiped with normal saline, and the lens was wiped with special lens paper. For patients with infectious diseases such as hepatitis B, they should be scrubbed with 0.5% "84" disinfectant first, then fumigated with 40% formaldehyde for maintenance, and managed and maintained by special personnel.