Advances in Brain Tumor Surgery
Until now, ultrasound has rarely been used to examine brain tumors. A working group at the Würzburg University Clinic has now shown that ultrasound technology offers tangible advantages in this area. The scientists gained this knowledge during brain tumor operations. They compared three methods of imaging: ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). All of these methods provide images of the conditions at the operation site. With the help of the images, the tumor can be distinguished from he althy tissue with varying degrees of ease.
During the operation, samples were systematically taken from the tumor and its peripheral areas and examined for histological examination. As the Würzburg scientists report, it was shown that the tumor borders can be determined better with ultrasound than with the other methods. This is mainly due to the fact that in most cases ultrasound also makes those parts of the tumor visible that do not absorb contrast media and are therefore difficult to distinguish from he althy brain tissue with CT and MRT. The risk of residual tumor remaining in the patient's brain is therefore lower during operations under ultrasound guidance.
In addition, the ultrasound method provides suitable layer images of the tumor even when examining through the closed skullcap. Overall, it has proven to be a valuable and reliable aid in the detection of tumor residues at the border to he althy brain tissue, the conclusion of the Würzburg scientists. Their findings call into question the use of technically complex and cost-intensive CT and magnetic resonance tomographs in the operating room.
This work was funded by the German Cancer Aid and led by PD Dr. Georg Becker and Prof. Dr. Andreas Krone from the interdisciplinary ultrasound working group at the Neurological and Neurosurgical Clinic and the Department of Pediatric Neurosurgery. Also important were Dr. Michael Woydt and Dr. Mathias Mäurer involved. The scientists used what is known as duplex sonography as the ultrasound system.
This not only provides high-resolution images, but also important additional information about vessels and blood flow in the examined organs. The blood flow in the vessels can be made visible and projected in color into the black and white cross-sectional image. The Doppler function also allows flow velocities to be determined and thus, for example, to distinguish arteries from veins. This information is valuable because it gives the doctor a picture of the extent to which blood vessels supply the brain tumor before the operation. Under certain circumstances, this could provide information about whether the tumor is benign or malignant, says Prof. Krone.
