Tools and methods of neurosurgeons in Assuta
Topographic mapping in the operations on the brain for tumors
While magnetic resonance spectroscopy or MRI neurosurgeons provide valuable information about brain tumors, they have not identified sensitive areas of the body that are responsible for speech, thought, sensation and movement. Mapping the brain during the operation sets the critical areas and determines necessary to remove the margin of healthy tissue.
Brain mapping tools include:
- direct stimulation of the cerebral cortex;
- somatosensory evoked potentials;
- functional MRI;
- intraoperative ultrasound imaging;
- intraoperative MRI.
Leading Israeli doctors perform brain surgery at the clinic Assuta. Here we use the most modern methods of treatment with the fewest possible side effects to improve patient's quality of life.
Highly qualified specialists work together to provide the team and individual approach to therapy. This achieves the best results. The team of experts may include neurosurgeons, radiation oncologists, and other medical neurooncology.
Direct cortical stimulation operations on the brain for tumors
This technique reveals the sensitive parts of the brain through direct contact with body tissue. For stimulation probe is used with a low dose of an electric current. When you touch a certain area of the brain occur visible movement associated with a particular part of the body. If the patient is awake, this method is used to determine the localization of critical areas of voice and feelings. So the surgeon identifies important areas of the brain.
Somatosensory evoked potentials
During this procedure the low dose electrical current to produce limb or facial. Electrodes placed on the surface of the brain, recorded weak electrical impulses that pass along the nerves to the brain. These pulses are called "evoked potentials" and is a tool for the detection of functionally important regions of the brain.
Functional MRI in the operations on the brain for tumors
For this method have a higher scanning speed snapshot with oxygen compared with conventional MRI. FMRI distinguishes healthy brain tissue utilizing oxygen from a tumor comprising dead cells and not in need of the substance.
Intraoperative ultrasound imaging
This technique during operation to determine the depth of the tumor and its resolution. Ultrasonic pulses are sent to the brain and instantly displayed on special equipment. The computer performs calculations, and an image is formed on the screen. With the intraoperative ultrasound imaging neurosurgeon:
- It defines the shortest path to the new formation;
- establishes its borders;
- distinguishes tumor from a cyst, swelling and healthy brain tissue.
Intraoperative MRI in operations on the brain for tumors
Assuta Hospital operating rooms are specialized MRI machine that scans carried out at the time of surgery. These images give the doctor information with similar information obtained from intraoperative ultrasound, but the images are more detailed.
Particularly useful intraoperative MRI during the cytoreduction, when most of the tumor is removed. Such navigation provides the surgeon is constantly updated images.
Embolization in operations on the brain for tumors
If the tumor has a large number of blood vessels, it may be difficult during surgery due to bleeding. Embolization - a technique used by neurosurgeons to stop the blood flow to the new formation before it is deleted.
Pre-angiography to find out if a significant amount of blood is concentrated within the tumor. If - large, neuroradiologist or neurosurgeon to place a small "plug" made of wire or glue-like material inside the vessel. This manipulation stops blood flow to tumors, but not to the healthy parts of the brain. Surgery to remove the tumor is carried out within a few days after that.
Embolization of tumors when used with a large number of blood vessels or "well developed vasculature" - meningiomas, hemangiopericytoma, and others.
Convection enhanced delivery (CED) in the operations on the brain in tumors
This is one of the newest methods of delivery of chemotherapy drugs and biological therapies to tumors. The procedure starts with the operation, during which several catheters or catheter (depending on the tumor size) was placed inside it. Neurosurgeon connects nasosobraznoe device (pump) to the catheter, filling it with a drug. The liquid moves through the zone of the tumor due to the pressure exerted. This method of convection delivery bypasses the blood-brain barrier, providing direct contact with the drug tumor tissue.
This method is now being studied in clinical trials for placing immunotoxins radioactive monoclonal antibodies and various cytostatic drugs to the site of the neoplasm. As this technology develops, researchers are studying the method of implementation of specific indicators in medicated substances. These indicators are visualized on MRI during the CED and allow scientists to observe in real time the movement of the therapeutic agents in and around tumors mode.
Removal of brain tumors by laser
Laser - a surgical instrument. The device emits a narrow beam of intense heat, through which cut tissue and evaporated during brain surgery. Laser rays do not pass through dense bone of the skull.
The use of this device is particularly effective in tumors:
- located at the base of the skull;
- deep within the brain;
- in all cases where it is difficult to remove the tumor for any other reason.
Lasers often involve microsurgery, during photodynamic therapy and for other diagnostic purposes. During laser interstitial thermal therapy is also used laser probe with guiding him in the deep-seated tumors. Will turn to this method during surgery depends on the doctor's experience and the best tools for the removal of options specific tumors.
Microsurgical brain surgery in case of tumors
Microsurgery involves the use of high powered microscope or other means of visual increase during surgery along with tiny surgical instruments that allow the neurosurgeon to perform the operation very delicate. This method is activated when the brain structure are extremely small and precise movement of the surgeon gets a key role. By turning microsurgery also when wrapped tumor blood vessels or nerves, or located at the base of the skull.
Neuro or endoscope - a long, narrow tube, equipped with a camera lens and light source at the end. It is used to visualize the hollow pathways in the brain, such as the ventricle. The endoscope is introduced through a small hole in the skull and lead to the ventricle. It provides coverage of the treated area in "real time." To it may be attached a surgical laser, a biopsy to eliminate clogging of the shunt to remove a tumor or a cyst in the ventricle. Since the endoscope is a long and very narrow, it is not used for resection of large tumors or those available through traditional surgical instruments.
Photodynamic therapy in operations on the brain for tumors
Photodynamic therapy - a procedure that uses a laser and the sensitizing drug. Before surgery the drug is administered into a vein or artery, where it spreads through the bloodstream and is absorbed by the tumor. The preparation contains the special compound, which makes fluorescent cell neoplasms. During the operation, the neurosurgeon sends a laser beam to the tumor, activating medication that destroys cancer cells.
To use this method, there are limitations:
- PDT is used, if a tumor is evaluated as "operability".
- Only the tumor cells are visible neurosurgeon can be identified and treated with a sensitizing drug. Part of the tumors can be hidden and not sensitive to light.
- Some tumors do not respond to this remedy.
- When tumors near the brain stem does not apply photodynamic therapy because of the risk of edema.
Polymer implants in operations on the brain for tumors
Since cancer cells can spread into the surrounding area, the doctors offer complementary therapies. Biodegradable polymeric Gliadel wafer used for this purpose. Impregnated in their chemotherapeutic drugs are placed into the tumor during surgery.
Traditionally cytostatic agent is administered intravenously or orally. One of the most common drugs - carmustine, or BCNU. Despite the fact that BCNU effective in some cases, its use may cause damage to the bone marrow when administered intravenously. To avoid this, the researchers developed a thin plate impregnated with the drug. They are placed directly into the cavity of the brain where the tumor was before. The plates are placed during surgery to remove tumors. It takes only a few minutes. It may be implanted to 8 plates. Within 2-3 weeks they slowly dissolve, releasing the drug into the surrounding cells. The plates do not need to be removed because they are biodegradable. This method:
- It provides a controlled and predictable delivery of the drug to the tumor.
- Eliminates traditional side effects that occur when the drug passes through all body neoplastic.
- Targeted delivers medication to the area that needs treatment.
- Is able to increase the risk of problems with wound healing.
- After applying this method, the patient may be regarded as unsuitable for certain clinical trials.
Stereotactic surgery operations on the brain for tumors
Using the most modern computers to detect tumors, creating a three-dimensional image is called its Stereotaxis. Application of this technique is called stereotactic surgery, during surgery. Conventional X-rays only measure the height and width. Stereotactic surgery adds a third option - the depth of which increases the ability of a neurosurgeon exactly match the location of the tumor and to find the best and safest way to remove it.
These methods are used for preparation for surgery, during a biopsy or removal of neoplasms, during implantation of radioactive pellets, to provide navigation during surgery. They are especially useful in finding and removing tumors located deep within the brain - in the trunk or the thalamus. Stereotactic system used in operating rooms Assuta, which allows surgeons to see images of the brain in the course of surgery. Some techniques used stereotactic frame, the other - no.
Stereotactic surgery using frames
The skull before surgery is fixed via a light frame at four points. To eliminate the pain using local anesthesia. Then, a CT, MRI or angiography. Set the exact location of the tumor in three dimensions. Neurosurgeon captures these coordinates through small incisions to insert the probe of a biopsy or other procedure.
There are limitations to this technique:
- Frame sometimes blocking your view of the surgical field;
- Manual installation frame can be time-consuming;
- there is a certain space to work within the arc radius;
- scan and the operation must be performed in the same day.
Frameless Stereotactic Surgery
Instead of using the outer frame as a reference point, frameless stereotaxis uses tiny tokens - fiducial marks that capture on film or adhered to the head prior to scanning. The resulting information is loaded into the navigation computer which creates a three-dimensional image and brain tumors. During the operation, a special device that identifies markers, directing the course of surgery.
There are many FDA approved neuronavigation systems. Most of them are equipped with computerized management, giving neurosurgeon fast, continuous, in "real-time" three-dimensional information on the location of the tumor.
Stereotactic surgery using microscope
Operating microscope monitors the coordinate markers, giving information about the localization of tumors established in the head. Image after CT or MRI is loaded into the microscope, it provides visualization during surgery.
Robotic brain surgery in case of tumors
Robotics allows surgeons to perform complex and lengthy surgery. The system consists of a computer, microscope and mechanical arms that hold the appropriate tools. The surgeon controls the robotic arms using special hand items.
Robotic surgery has advanced significantly neurosurgery. Now, however, it is mainly used for research purposes.
In the future, the use of robotics can:
- Reduce the burden of the surgeon during the long and complex operations.
- Improve the technical specifications with greater precision.
- Provide surgeons performing surgical procedures remotely.
Ultrasonic aspiration in operations on the brain for tumors
This technique uses a vibration created by the ultrasonic waves to break into pieces neoplasm, which is then removed in pieces. Aspiration minimizes the possibility of the spread of tumor cells to other parts of the brain. This method is not suitable when tumors solid consistency.