Image-guided Brain Tumor Surgery

High-Frequency Ultrasound
High-frequency ultrasounds are different than diagnostic ultrasounds. High-frequency ultrasounds use powerful waves to shatter large tumors into tiny pieces without any incisions. These smaller tumor pieces can be more easily removed during surgery. The surgeon can core the tumor with this technique, much as one would core the pulp of an orange. Then, the skin or the outside of the tumor can be more easily dissected away from surrounding structures. High-frequency ultrasound waves are precisely focused to break apart abnormal cells without damaging healthy brain tissue.

BrainPath® Technology and the Six Pillars
Houston Methodist is one of only a dozen facilities in the country to offer a new brain surgery technology called BrainPath. It is used — along with other minimally invasive techniques — to help neurosurgeons safely maneuver to deep, hard-to-reach areas of the brain. Surgeons access the brain through a dime-sized port while neuro-navigation and three-dimensional imaging help guide them safely through the brain's folds and corridors, along the safest route to the tumor. Tumors and blood clots are suctioned out with a non-heated device. With this technique, most patients are discharged on the morning after surgery.


Neurosurgeons at Houston Methodist  have been pioneers in new approaches to removing brain tumors that just a short while ago would have been considered inoperable because they are located deep in the brain.  Our neurosurgeons are experts in using a novel  brain surgery system called BrainPath. This revolutionary technology is transforming brain surgery: Houston Methodist neurosurgeons are planning and performing surgeries that they would never before have attempted.   We remain one of only a dozen programs in the country to offer this approach to our patients. We also educate other neurosurgeons about how to help their patients by using use this powerful new approach. The Six Pillars approach using the BrainPath technology allows neurosurgeons to safely maneuver to deep, hard-to-reach areas of the brain that were previously inaccessible. It is an opportunity to offer life-saving surgery where previously no options might have existed. The Six Pillars include the following elements:

• Image interpretation and trajectory planning – Existing brain images can be used to map a path to the tumor that spares normal tissue
• Navigation – Like GPS (global positioning system) BrainPath technology guides the neurosurgeon in real time as they perform the operation
• Optics – High definition optics provide a clear picture during surgery
• Safe access – A slender device called an obturator is used to gently move normal tissues out of the way as it is inserted. The obturator has a sheath on the outside and a core that is removed after the tip reaches the tumor. This creates a hollow tube or tunnel through which the procedure can take place without injuring normal brain tissue.
• Resection – The tumor is carefully removed (resected)
• Targeted therapy/neoadjuvant (chemotherapy) – The removal of tumor tissue without damaging it opens the door to possible targeted therapy.

Surgeons access the brain through a dime-sized port, while neuronavigation and 3-D imaging help guide them safely through the brain’s folds and corridors, along the safest route to the tumor. Tumors and blood clots are suctioned out with a non-heated device. With this technique, most patients are discharged on the morning after surgery.

Craniotomy
A craniotomy is a type of surgery in which part of the skull bone is removed so the surgeon can access the brain. This section of skull (called the bone flap) is replaced at the end of surgery. There are different types of craniotomy.

• Stereotactic craniotomy uses the virtual imaging guidance system before surgery to plan the safest route to the tumor. This, along with 3-D scans, helps pinpoint the tumor’s exact location in the brain and distinguish the tumor from healthy tissue.
• Craniectomy temporarily removes a section of the skull when swelling is likely. It is a life-saving procedure when brain swelling would otherwise be fatal. The bone is stored in a tissue bank and replaced at a later date.

Functional Magnetic Resonance Imaging (fMRI)
Conventional MRIs show brain anatomy and are very helpful both before and during brain surgery. New functional MRI technology, however, goes even further to show brain activity in response to stimuli. This type of functional brain mapping shows neurosurgeons where in the brain's critical functions, such as speech and language, sensation vision, and motor functions, are located.

Functional MRI helps neurosurgeons plan their approach to tumors during complicated brain surgeries to avoid damaging surrounding tissues. This kind of fMRI brain mapping offers a quicker, more accurate, and less invasive alternative to direct electrocortical stimulation (ECS), where electrodes are placed on the surface of the brain to measure and map brain activity. It makes previously inoperable tumors accessible for surgical removal.
 
Minimally Invasive Surgery for Brain Tumors
Whenever possible, our neurosurgeons use the least invasive approach that promises the best treatment outcome. Many times, a traditional craniotomy can be replaced with a minimally invasive technique that requires only small incisions and minimal bone removal. This results in less blood loss, less brain and structural manipulation and less scarring. Minimally invasive surgeries are used to reach most brain tumors successfully.

Minimally invasive surgery options include supraorbital (eyebrow), retrosigmoid (keyhole) and endoscopic surgeries, including endonasal (through the nose) .
 
Supraorbital (eyebrow) approach
This less invasive type of craniotomy uses a small incision in the eyebrow to access tumors in the front of the brain or in the pituitary gland. Sometimes this is a better option than endonasal endoscopy   when tumors are large, or are near the optic nerve or major arteries. The eyebrow is not shaved and once healed, the incision is virtually undetectable.

 
Retrosigmoid (keyhole) surgery
This surgical technique uses a small incision behind the ear to reach tumors at the base of the skull, brainstem and back of the head.

Minimally Invasive Endoscopies
An endoscope is a narrow tube with a tiny, telescope-like video camera on the end that lets surgeons view internal structures on a high-resolution screen. Only small incisions — and sometimes none at all — are needed to perform an endoscopy. Surgeons can also attach small surgical instruments to the endoscope to cut away and remove diseased tissue. Endoscopic craniotomy uses a tiny endoscope and camera inserted through a small incision in the skull, or introduced endonasally (through the nose) without any incision.

LEARN HOW NEW TOOLS SUCH AS THE NEUROENDOSCOPE, ROBOTIC ARMS AND SPECIAL SURGICAL INSTRUMENTS ARE USED IN MINIMALLY INVASIVE SURGERIES.

Endonasal endoscopy 
During endonasal endoscopy, the surgeon inserts an endoscope through the nose to reach the pituitary gland and brain without any incisions. This kind of endoscopy is often used to treat hard-to-reach tumors, pituitary tumors and tumors that were previously considered inoperable. The endoscope allows the surgeon to “look around the corner” and visualize structures in ways not previously possible. The system uses a tiny endoscope about 1/10 of an inch in diameter, and has Blu-ray definition .
 
Endonasal endoscopy has several advantages over more invasive techniques:

• Less pain
• No visible scars
• A shorter surgery and recovery time
• Reduced hospital stays — often patients can be discharged on the morning after surgery
• Improved outcomes

Virtual-Image Guidance System
Neurosurgeons at the Peak Center use a virtual-image guidance system to achieve unprecedented surgical accuracy. This virtual-reality system uses magnetic resonance imaging (MRI) to provide surgeons an expanded, high-definition view of tiny, yet critical, areas of the brain. This helps surgeons stay within safe corridors of the brain, and avoid damaging surrounding areas that are essential to body and cognitive functioning. In fact, using this latest technology allows surgeons to be accurate within one millimeter. The system helps neurosurgeons treat multiple tumors, which would have been too dangerous with earlier techniques.

Our surgeons also use virtual-image guidance before surgery to help plan the safest, least invasive path to the tumor during surgery, including craniotomy. They can perform the surgery in virtual-reality first, before the actual surgery is done, making the operation much more safe and precise.