Finding answers in MRIs

[Source: BY WILLIAM ROLLER, SUN STAFF WRITER] - The medical research lab may lack the drama of the Emmy Award-winning "ER" TV show but a Yuma pre-med student applied her passion for science to search for possible discoveries that can impact health and the community at large.

Norianne Pimentel, 19, a 2006 Cibola graduate and now a pre-physiological sciences junior at the University of Arizona, is enjoying her summer investigating ways magnetic resonance imaging (MRI) could someday lead to answers about life-threatening disease.

Supported by grants from the National Institutes of Health and the Howard Hughes Medical Institute, Pimentel is an intern assistant of primary investigator Dr. Natarajan Raghunand in the Undergraduate Biology Research Program at the UA.

The program is strictly lab work but may provide vital links in cancer research, Pimentel said. Cancer can be difficult to detect but the sooner it is found, the better the chances are of treating it.

Imaging techniques, procedures used to photograph inside the body, can play a critical role. Imaging alone is not a treatment but does aid in making proper decisions about treatment.

"I don't do X-rays but only MRIs that use pictures to see what's there," Pimentel said. "A lot of imaging scans use a contrast, iodine, injected in the blood. But an MRI is much less invasive than a CT (computed tomography) scan."

Using MRIs, Pimentel is examining mouse kidneys while assessing two imaging techniques: Flow-sensitive Alternating Inversion Recovery Arterial Spin Labeling (FAIR-ASL) MRI and Dynamic Contrast Enhanced (DCE) MRI.

FAIR-ASL uses water already in the blood as a contrast medium, while DCE uses tracers like the rare metal gadolinium. Both are safer than present methods and could be used to examine blood flow in people, she said.

"So, if you see a bright patch, a different contrast, it will modulate the signals the tissue sends to the machine," Pimentel said.

By examining kidneys of laboratory mice, the goal is to optimize imaging techniques so that when there is a malfunction, doctors can assess it more quickly and with greater accuracy. One of the ailments it can spot are tumors.

"I can look at the blood flow and tell whether a tumor is vascular (receiving blood flow) and what area of the tumor is getting nourishment."

She went on that if a tumor is getting blood supply, it can metastasize (spread), which is of critical concern while nonvascular tumors tend to be less dangerous. The MRI also aids to pinpoint the area to perform a biopsy, the extraction of tissue for examination.

"My job is to see how it's working in terms of imaging, which provides another piece of information to treat the ailment," Pimentel said. "It provides bigger pieces of the puzzle of what may be malfunctioning."

Different researchers have different goals, she said. But the ultimate goal is to provide more insight into the health and well-being of the human body, she explained.

"Whatever your goal in medical research is, you're looking for an advancement that can change somebody's life down the line."

Of the many fields that fall under the medical umbrella, Pimentel said she wants to remain open to several. Medical school is definitely on her agenda and she is leaning toward a career in radiology, neurology or diagnostic medicine.

Pimentel recommended, that high school seniors pondering a career path seriously consider research because it affords so many opportunities.

"I always thought about returning to Yuma. I love the city and loved growing up there. I would be glad to return and work at YRMC (Yuma Regional Medical Center)."