History of Imaging Brain Tumors

Late 1800s: Discovery of X-rays

Before the discovery of X-rays in 1895, brain tumors resulted in death. Not long after X-rays were discovered, it was noted that they had limited use in diagnosing brain tumors. X-rays are better at providing pictures of solid structures, like bones. The brain is made up mostly of soft tissues that don’t show up well on X-rays.

Early 1900s: Introduction of Pneumoencephalography

A procedure called pneumoencephalography was introduced in 1919 that allowed cerebrospinal fluid to be drained from around the brain and replaced with air. This allowed the structures of the brain to show up on X-ray more clearly. It is one of the first techniques that allowed the living brain to be visualized.

As medicine continued to advance throughout the 1900s, new imaging methods were invented and imaging of the brain continued to improve.

Later 1900s: CT and MRI Are Invented

1n 1971, the ability to image the brain changed dramatically with the introduction of computed tomography (CT) scans. A CT scanner takes multiple X-ray images of the body from different angles. It provides more detailed images than plain X-rays do.

Around this same time, the use of a “contrast medium” was made safer, where a special dye is given to the patient before the CT scan. The contrast helps create a clearer picture. You may also here this referred to as a contrast agent.

Advances with CT scanning continued throughout the 1970s.

Magnetic resonance (MR) was also being explored in the early 1970s. The first MR images of a human were reported in 1977 (the scientists who led this later received a Nobel Prize for their work).

Magnetic resonance imaging (MRI) was a completely new way of imaging in that it did not rely on X-rays. That means it doesn’t use radiation, so it’s a safer imaging option. Instead of X-rays, this imaging technology creates 3-D images of the body’s internal anatomy using strong magnetic fields and radio waves.

The first paper to be published about the potential for using MRI to view pediatric brain tumors was in 1985. The use of contrast agents with MRI (similar to CT with contrast described above) came soon after that. Today, using MRI with contrast to image a brain tumor remains the optimal way to diagnose medulloblastoma.

Early 2000s

Advances in imaging techniques over the last several decades have improved understanding of brain tumors. Other types of scans have been developed and improved upon, in addition to CT and MRI; however, they are not routinely used in the diagnosis and treatment of medulloblastoma.

One more recent technology that may be used with medulloblastoma tumors is intraoperative MRI (abbreviated as iMRI). This refers to an MRI that can be done in the operating room after surgical resection of a tumor but before closing the surgical site. Using iMRI allows the surgeon to view a high-quality scan of the surgical area to make sure as much of the tumor as possible has been removed before finishing the procedure.

Despite advances in imaging technology, imaging features that can help predict prognosis of medulloblastoma have not yet been discovered. New imaging techniques, including magnetic resonance spectroscopy (MRS), perfusion imaging and positron emission tomography (PET), may someday help experts better understand the biology of this tumor, and in turn improve the treatment of medulloblastoma.