"We can view the brain from the inside out now, with 3D images
detailing connectivity within the brain, making a virtual intraoperative
map," said senior author Steven Brem, MD, professor of Neurosurgery,
chief of the Division of Neurosurgical Oncology and co-director of the
Penn Brain Tumor Center. "Penn is at the forefront of a major shift in
the field -- we now have such detail about each individual's brain tumor
-- combining diffusion tensor imaging and advanced imaging with the
entire personalized diagnostics analysis available for all brain tumor
patients at Penn Medicine."
Diffusion tensor imaging (DTI) provides a rendering of axon
pathways, by tracking water molecules in the brain as they travel in a
direction parallel to axonal fibers, in a 3D model known as "the
diffusion tensor." The diffusion tensor directly represents the
direction of water and indirectly represents the orientation of white
matter fibers. The colorful images, captured as part of an 8 minute
sequence during an MRI, show representations of clusters of axon fibers,
where each color indicates a direction of travel, and offer a glimpse
of the interwoven communication superhighways of the brain.
"The DTI images can be overlaid with structural and functional MRI
images, providing a hybrid map showing topography layered with a road
map," said Neurosurgery resident Kalil Abdullah, MD, lead author of the
paper. "This rendering gives us increased clarity to visualize important
white matter tracts in the brain and adapt our surgical approaches to
each person's case. Rather than focusing on solely taking the tumor out,
we can avoid damage to healthy tissue and preserve important pathways
responsible for speech, vision and motor function. "
Relying heavily on the expertise of radiologists who process and
analyze the DTI images, including Ronald L. Wolf, MD, PhD, associate
professor of Radiology at Penn, the research on DTI is being translated
into clinical practice to guide surgical procedures. Further research
efforts are targeted at defining language deficits before surgery and
following-up post-operatively to determine any changes or improvements
following treatment based on the use of DTI.
Working collaboratively with colleagues in Penn's departments of
Neurosurgery, Neurology, Radiology, Radiation Oncology, Nursing,
Pathology and Laboratory Medicine and the Abramson Cancer Center, the
Penn Brain Tumor Center combines the latest imaging, biomarker and
genetic tumor testing to provide a personalized treatment plan for all
types of brain cancers. Brain tumors are among the first areas of
interest for Penn's Center for Personalized Diagnostics (CPD), a joint
initiative by Penn Medicine's Department of Pathology and Laboratory
Medicine and the Abramson Cancer Center, which integrates Molecular
Genetics, Pathology Informatics, and Genomic Pathology for
individualized patient diagnoses and to elucidate cancer treatment
options for physicians.
Additional co-authors on the Neurosurgical Focus article include Paolo Nucifora, MD, PhD, from Penn's Department of Radiology and Daniel Lubelski, BA, with the Cleveland Clinic Lerner College of Medicine. The study was funded by the Departments of Neurosurgery and Radiology at the University of Pennsylvania.