MRI guided biopsies are usually performed for lesions that are found on for example liver or breast MRI procedures and that are not seen on computed tomography, ultrasonography or mammography. The identification of cancer on breast MRI is dependent on uptake of intravenous contrast agents.
First an MRI scan, using a dedicated breast coil and biopsy guidance system is performed to found the lesion. After skin disinfection and local anesthesia, the biopsy procedure starts. Possible MR guided interventions include fine needle aspiration, core needle biopsy and vacuum-assisted biopsy (VABB) to sample tissue from the lesion; or wire localization prior to surgery for lesions that are not palpable.

See also Breast MRI.

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.

(FAME) The FAME MRI technique uses a 3dimensional fast SPGR pulse sequence to acquire high resolution images. With its short scan time, FAME is useful for dynamic liver imaging with multiple phases.

(HASTE) A pulse sequence with data acquisition after an initial preparation pulse for contrast enhancement with the use of a very long echo train (Single shot TSE), whereat each echo is individually phase encoded. This technique is a heavily T2 weighted, high speed sequence with partial Fourier technique, a great sensitivity for fluid detection and a fast acquisition time of about 1 sec per slice. This advantage makes it possible for using breath-hold with excellent motionless MRI, e.g. used for liver and lung imaging.

See also Segmented HASTE.

(LAVA) The MRI technique LAVA is based on a 3 dimensional spoiled gradient echo pulse sequence. The optimized inversion pulse and a new fat suppression technique (called segmented special) provides enhanced image contrast and uniform fat suppression. Array spatial sensitivity encoding technique (ASSET) with partial data filling and shorter TR/TE enables to use short breath holds for dynamic liver imaging with multiple phases.