3D MRI enhances visualization, displays fetal anatomy and diagnosing problems

Three-dimensional MRI is an emerging and useful technique for displaying fetal anatomy and diagnosing problems in the womb in a wide spectrum of clinical applications, according to Jeffrey C. Hellinger, M.D., a pediatric imaging specialist at Stony Brook University Medical Center.

"Through enhanced visualization, 3D MRI improves one's understanding and ability to display fetal anatomy. With a better understanding and display of anatomy, it enhances exam interpretation and communication," said Dr. Hellinger, who details the uses and advantages of the technique in "Fetal MRI in the Third Dimension," a review published in the July-August issue of Applied Radiology, the journal for radiologists, and available online.

"I joined Stony Brook to help advance pediatric imaging, beginning with select imaging protocols, and this is one of them," said Dr. Hellinger, who came to SBUMC around the June 2010 launch of Stony Brook Long Island Children's Hospital, the only dedicated children's hospital east of the Nassau/Queens border.

Stuart E. Mirvis, M.D., Editor-in-Chief of Applied Radiology, comments on the piece, writing "Our cover story this month is quite likely the first article of its kind. It is an excellent review of 3D Fetal MRI techniques…The article does more than illustrate several flashy pictures that can be generated on 3D workstations and instead shows clinical radiologists, who may not be as familiar with this technology, that not only can it be done, but there are very beneficial emerging applications."

3D sequences, which are available with fetal MRI at SBUMC, has distinct advantages for the pregnant mother, Dr. Hellinger points out. Because the fetus is moving frequently during a typical 20-24 week exam, 2D MRI necessitates obtaining multiple images in multiple planes. "That translates to a fairly long exam, an average of 30 minutes to 45 minutes. For any patient an MRI can be discomforting, let alone someone who is pregnant."

With a 3D MRI, a practitioner can obtain volumetric, high resolution images that can be manipulated to view in any plane desired, obviating the need for redundant 2D images and potentially decreasing the overall exam time. "With the right image quality, that means less time in the magnet for the mom, improving workflow, and improving patient satisfaction," he explained.

Ultrasound and the newer 3D ultrasound remains the "principle obstetrical imaging modality. It is readily performed in outpatient and inpatient settings at minimal inconvenience to the mother, yielding reliable information for immediate clinical counseling and management," Dr. Hellinger writes in the Applied Radiology article. However, Dr. Hellinger writes that MRI "offers superior spatial resolution and structural detail, affording comprehensive anatomical displays from single acquisitions.

"MRI is often requested to provide more definitive anatomical understanding and diagnosis for abnormalities identified on the screening ultrasound, as well as to assess for concomitant abnormalities. The literature has also advocated its use for anatomical screening in the setting of congenital heart disease and predisposed families."

3D MRI at Stony Brook University Medical Center

The 3D MRI has numerous uses at SBUMC for pediatric imaging. Physicians practicing in various subspecialties, such as Maternal-Fetal Medicine, Pediatric Cardiology, and Pediatric Pulmonology, Allergy and Immunology, are beginning to use the imaging modality.

"Ultrasound serves as the standard test to evaluate non-cardiac fetal anatomy, and MRI imaging for fetal, placental, and uterine abnormalities can be useful in confirming or clarifying possible abnormalities that ultrasound detects. But because of our inability to control fetal movement in utero, the shorter time taken to get 3D MRI images of fetuses gives us a better chance of getting useful fetal images than standard 2D MRI," says Paul, Ogburn, M.D., Director, Maternal-Fetal Medicine.

"Three-D imaging can act as an adjunct to add to our understanding of congenital heart defects and also of any other congenital abnormalities that may be present in the fetus," says Laurie Panesar, M.D., Assistant Professor of Pediatrics in the Division of Pediatric Cardiology. "By detecting these types of problems prenatally, we can better prepare for the baby's birth and also better prepare the parents what to expect when their baby is born."

Thomas Biancaniello, M.D., Chief of Pediatric Cardiology, adds that 3D MRI is beneficial for imaging the fetus because "the diagnostician may have little control of the views obtained by fetal echocardiography because of the fetal position.

"3D MRI has been shown to be useful in infants, older children, and teenagers with congenital heart disease, as it allows visualization of structures that are out of the range of more conventional imaging," he explains.

According to Catherine Kier, M.D., Chief of Pediatric Pulmonology, Allergy and Immunology, and Director, Cystic Fibrosis Center, 3D MRI plays into the importance of early diagnosis, which is critical regarding long-term pediatric patient outcomes.

"Congenital pulmonary abnormalities like diaphragmatic hernia and cystic lung lesions can be diagnosed with state-of-the-art fetal imaging like 3D MRI. This in combination with subspecialty collaboration and comprehensive services will lead to excellent patient outcomes."

Dr. Hellinger's article contains striking fetal images taken with 3D MRI. He and co-author Monica Epelman, M.D., of the Department of Radiology at The Children's Hospital of Pennsylvania, conclude the article on 3D fetal MRI stating, "Successful utilization requires optimized image quality and understanding of advanced visualization techniques. Continued evidence-based investigation is required to determine the impact of 3-dimensional fetal MRI on fetal diagnosis and management."

Source : Stony Brook University Medical Center