Operation Of Brain Tumors
When Does Surgery Have To Be Done?
Operation Of Brain Tumors, The most important aspects in the choice of the therapy of brain tumors are the efficiency and the risks of the therapy, as well as the biological behavior of the tumor itself. An indication for surgery is given when:
- The tumor is readily accessible and removable for operation with the individually available techniques and instruments,
- The tumor exerts a great space-demanding effect on the environment and shows a rapid progression,
- The overall condition and, last but not least, the patient’s age
The surgical therapy of infiltrating growing gliomas is only a part of the therapy and can usually not cure the tumor. Therefore, the type of necessary surgical therapy is first clarified. This can be a sampling, partial or subtotal or even total removal of the tumor. When a nerve water drainage through the tumor occurs, a nerve water accumulation (hydrocephalus) can occur, which may necessitate a nerve drainage operation (shunt, valve operation).
The Aim Of The Surgical Therapy İs:
- The improvement of the quality of life
- The delaying of a deterioration
- The improvement of conditions for subsequent therapies such as radiotherapy and chemotherapy
Unless an open operation is planned, a sampling can be performed computer-controlled with a stereotactic technique for fine-web examination. Stereotaxy is a Greek word: “defining a point in three-dimensional space by means of mathematical principles”.
The stereotactic sampling is performed in the majority of cases with frames which are temporarily attached to the head. Points in the brain are calculated and calculated using mathematical calculations.
The sampling is carried out seamlessly with a neuron navigation system. This works with stereotactic arm or magnetic fields or ultrasonic pulses or infrared rays with passive or active marker technology. The difference between neuronavigation and conventional stereotactic technique is that the operator can check the location of his instruments during surgery by showing the corresponding CT or MRT layer on the computer’s screen. Neuronavigation can be used to calculate different target points as well as volumes of the tumor to be removed. However, neuronavigation does not reach the precision of conventional stereotaxy but is faster and can be used in larger tumors.
Indications For Stereotactic Sampling Are:
- Small tumors in unfavorable localization (basal ganglia, brainstem, etc.)
- Diffuse growing tumors
- Large cystic tumors
- Elderly patients
- Patients with low Karnofsky index
The aim of the open surgery is as complete tumor removal as possible without impairing neurological functions. To achieve this goal, numerous techniques are now being used. Which includes:
- Fluorescence-assisted resection with ALA (Gliolan®)
- Functional monitoring (neurophysiological monitoring, operations with wax phases)
- Intra-operative imaging (MRI, CT)
In the case of the operation with navigation support, the patient must be prepared either the previous evening or the day of the operation, if the operating room has a CT or MR device.
In general anesthesia (occasionally also in local anesthesia if it is an operation near the speech center), the head is stored according to the position of the tumor and fixed in a three-point head clamp. After a straight or arcuate cut, the bone cap is mostly sawn with the high-pressure drilling system. The hard brain is opened.
The tumor is roughly targeted with the navigation guidance. This is removed under microsurgical conditions. The ultrasonic suction device is often used as an auxiliary instrument in larger tumors. In fluorescence-assisted resection, the patient receives a drug before the operation, which during the operation makes some tumors more visible by their fluorescence under blue light. The extent of tumor removal depends on the adjacent functional areas which are not to be damaged. During operations near the important functional centers, an intraoperative neurophysiological monitoring is performed in which the function of the sensory and motor tracts as well as the auditory pathway and other brain nerves such as those for facial, tongue, shoulder muscles etc. are monitored during the operation. The same applies to the monitoring of speech function in local anesthesia.
After complete blood discontinuation and, if necessary, intraoperative imaging control (CT or MR), the hard brain membrane and the wound are closed. The patient is moved to the neurosurgical monitoring station, where he wakes up. Normally, an MR or CT check is performed the next day or 48 hours after the operation at the latest to determine the outcome of the operation. On the first day after the operation, the patient returns to the general ward without any complications and can be mobilized step by step with the help of physiotherapy so that the patient can leave the clinic after 7 to 10 days (home, home hospital, rehabilitation clinic etc. ).
A cortisone administration for 3 to 7 days after the operation is generally carried out, the reduction takes place stepwise depending on the clinical and radiological findings. An additional therapy, eg radiation therapy and chemotherapy, is connected as a function of the fine-web examination result. Clinical and MRI control is performed approximately 4 weeks after radiation therapy, and then every 2-3 months depending on the tumor. In benign tumors, the control can be performed every 6 to 12 months.