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.

(MR mammography) Magnetic resonance imaging of the breast is particularly useful in evaluation of newly diagnosed breast cancer, in women whose breast tissue is mammographically very dense and for screening in women with a high lifetime risk of breast cancer because of their family history or genetic disposition.
Breast MRI can be performed on all standard whole body magnets at a field strength of 0.5 T - 1.5 Tesla. Powerful gradient strengths over 15 mT/m will help to improve the balance between spatial resolution, scanning speed, and volume coverage. The use of a dedicated bilateral breast coil is obligatory.
Malignant lesions release angiogenic factors that increase local vessel density and vessel permeability. Breast cancer is detectable due to the strong enhancement in dynamic breast imaging that peaks early (about 1-2 min.) after contrast medium injection. If breast cancer is suspected, a breast biopsy may be necessary to secure the diagnosis.

See also Magnetic Resonance Imaging MRI, Biopsy and MR Guided Interventions.

Requirements in breast MRI procedures:
For Ultrasound Imaging (USI) see Breast Ultrasound at Medical-Ultrasound-Imaging.com.

See also the related poll result: 'MRI will have replaced 50% of x-ray exams by'

Contrast enhanced MRI is a commonly used procedure in magnetic resonance imaging. The need to more accurately characterize different types of lesions and to detect all malignant lesions is the main reason for the use of intravenous contrast agents.
Some methods are available to improve the contrast of different tissues. The focus of dynamic contrast enhanced MRI (DCE-MRI) is on contrast kinetics with demands for spatial resolution dependent on the application. DCE-MR imaging is used for diagnosis of cancer (see also liver imaging, abdominal imaging, breast MRI, dynamic scanning) as well as for diagnosis of cardiac infarction (see perfusion imaging, cardiac MRI). Quantitative DCE-MRI requires special data acquisition techniques and analysis software.
Contrast enhanced magnetic resonance angiography (CE-MRA) allows the visualization of vessels and the temporal resolution provides a separation of arteries and veins. These methods share the need for acquisition methods with high temporal and spatial resolution.
Double contrast administration (combined contrast enhanced (CCE) MRI) uses two contrast agents with complementary mechanisms e.g., superparamagnetic iron oxide to darken the background liver and gadolinium to brighten the vessels. A variety of different categories of contrast agents are currently available for clinical use.
Reasons for the use of contrast agents in MRI scans are:
Common Indications:
Brain MRI : Preoperative/pretreatment evaluation and postoperative evaluation of brain tumor therapy, CNS infections, noninfectious inflammatory disease and meningeal disease.
Spine MRI : Infection/inflammatory disease, primary tumors, drop metastases, initial evaluation of syrinx, postoperative evaluation of the lumbar spine: disk vs. scar.
Breast MRI : Detection of breast cancer in case of dense breasts, implants, malignant lymph nodes, or scarring after treatment for breast cancer, diagnosis of a suspicious breast lesion in order to avoid biopsy.

For Ultrasound Imaging (USI) see Contrast Enhanced Ultrasound at Medical-Ultrasound-Imaging.com. See also Blood Pool Agents, Myocardial Late Enhancement, Cardiovascular Imaging, Contrast Enhanced MR Venography, Contrast Resolution, Dynamic Scanning, Lung Imaging, Hepatobiliary Contrast Agents, Contrast Medium and MRI Guided Biopsy.

Possible MR guided interventions are breast MRI, liver and bone biopsies. Open MRI is advantageous to guide interventional procedures because this type of MRI scanner provides a better patient access.
Before the MRI guided biopsy is started, all the necessary precautions ensuring normal sterile and safe conditions for an intervention have to be performed. This includes the special safety issues concerning MRI surroundings and special equipment, like non-magnetic biopsy needles, localization tools (e.g. wires to mark lesions prior to surgery with breast MRI guidance) etc.

See also 5 Gauss Line, Contraindications, Low Field MRI, MR Compatibility, Magnetic Resonance Guided Focused Ultrasound and Computer Aided Detection.

Aurora Imaging Technology, Inc., a private company, is located in North Andover, Massachusetts. As a leading innovator in the breast imaging industry, the company provides with its Aurora System the detection, diagnosis, biopsy and treatment of breast cancer. Aurora Imaging Technology Inc. develops and manufactures the Aurora® 1.5T Dedicated Breast MR System, the first and only FDA approved MRI system designed specifically for breast imaging.

MRI Scanners: