Ultrasound imaging is the primary fetal monitoring modality during pregnancy, nevertheless fetal MRI is increasingly used to image anatomical regions and structures difficult to see with sonography. Given its long record of safety, utility, and cost-effectiveness, ultrasound will remain the modality of first choice in fetal screening. However, MRI is beginning to fill a niche in situations where ultrasound does not provide enough information to diagnose abnormalities before the baby's birth. Magnetic resonance imaging of the fetus provides multiplanar views also in sub-optimal positions, better characterization of anatomic details of e.g. the fetal brain, and information for planning the mode of delivery and airway management at birth.

Indications:
Modern fetal MRI requires no sedatives or muscle relaxants to control fetal movement. Ultrafast MRI techniques (e.g., single shot techniques like Half Fourier Acquisition Single shot Turbo spin Echo HASTE) enable images to be acquired in less than one second to eliminate fetal motion. Such technology has led to increased usage of fetal MRI, which can lead to earlier diagnosis of conditions affecting the baby and has proven useful in planning fetal surgery and designing postnatal treatments. As MR technology continues to improve, more advances in the prenatal diagnosis and treatment of fetal abnormalities are to expect. More advances in in-utero interventions are likely as well. Eventually, fetal MRI may replace even some prenatal tests that require invasive procedures such as amniocentesis.

For Ultrasound Imaging (USI) see Fetal Ultrasound at Medical-Ultrasound-Imaging.com.

GE Healthcare is the result of the merger between GE Medical and Amersham Health in Nov. 2004, after GE acquired Amersham Health for 9.5 billion in Oct. 2003. Jeffrey R. Immelt, Chairman of the Board and Chief Executive of General Electric, said, 'Amersham's diagnostic pharmaceutical and life sciences business will add new, high growth platforms to GE Medical's diagnostic imaging, services and healthcare information technology businesses'. GE Healthcare, a UK company, is a unit of General Electric (NYSE: GE). GE Healthcare is a global leader in medical imaging, diagnostic imaging contrast agents, interventional procedures, healthcare services, and information technology. For more than 100 years, health care providers have relied on GE Medical Systems, now GE Healthcare, for high quality medical technology and productivity solutions. GE Healthcare, headquartered now at formerly seat of Amersham Health in Great Britain, operates facilities around the world. Global Operations include organizations on the Americas, Europe, and Asia, including India, Japan, Korea China, Thailand and Vietnam.

MRI Scanners:

0.2T to 1.0T:
to 1.5T:
to 3.0T:

MRI Contrast Agents:

From Philips Medical Systems;
The clinical capabilities of MR will further expand. Inside and out, the Achieva is a friendly, open system designed for optimal patient comfort and maximized workflow with high functionality. The Achieva 1.5T can be upgraded to Achieva I/T, with three configurations optimized for MR guided interventions and therapy:

With an open configuration MRI system neurosurgical procedures can be performed using image guidance. Open MRI can be used to guide interventional treatments or procedures, such as a biopsy.
Intraoperative MRI allows lesions to be precisely localized and targeted. Constantly updated images, correlated with images obtained pre-operatively, help to eliminate errors that can arise during framed and frameless stereotactic surgery when anatomic structures alter their position due to shifting or displacement of, e.g. brain parenchyma.
Intraoperative MRI can help with the identification of normal structures, such as blood vessels and is helpful in optimizing surgical approaches, achieving complete resection of intracerebral lesions, determining tumor margins and monitoring potential intraoperative complications.

Advantages of low field imaging are the small-sized 5 Gauss fringe field and therefore the less static magnetic field exposure for the surrounding area, as well as less contraindications causing lower risks for the MRI safety by implemented metal and magnetic devices and equipment.
Low field systems are sometimes for restricted use, e.g. dedicated extremity scanner or open MRI devices. Open MRI devices equipped with permanent magnets are well-suited for MR guided interventions because these machines combine the lower magnetic fields of this type of magnets and the better patient access of open MRI scanner.
In some cases, the contrast of different tissues is better at lower field strength, depending on their T1 or T2 relaxation times. The disadvantage of the lower signal to noise ratio are a poor resolution and a longer scan time for a good image quality.

See also Claustrophobia, Contraindications and MRI Safety.

See also the related poll result: 'In 2010 your scanner will probably work with a field strength of'