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GE Medical Systems and Amersham announced in April 2004 the completion of a share exchange acquisition of Amersham Health by GE. The result of this acquisition is the new GE Healthcare, based in the UK, totally owned by General Electric (GE).

Amersham plc, was a producer of contrast imaging agents used to enhance image quality in X-ray, magnetic resonance imaging, and ultrasound procedures. It was also a leading producer of radiopharmaceuticals used in nuclear medicine imaging. Amersham Health was the firm's imaging, diagnostics, and therapeutics segment. Amersham plc was involved in biotechnology research through its Amersham Biosciences unit, which made scanners, sequencers, microarrays, industrial separations, and other research supplies.

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.

A bolus is a rapid infusion of high dose contrast agent. Dynamic and accumulation phase imaging can be performed after bolus injection. Since the transit time of the bolus through the tissue is only a few seconds, high temporal resolution imaging can be required to obtain sequential images during the wash in and wash out of the contrast material and, therefore, resolve the first pass of the tracer.
For the same injected dose of contrast agent the injection rate (and, consequently, the total injected volume) modifies the bolus peak profile. Increasing the injection rate produces a sharpening of the peak (Cmax increase, Tmax decrease, peak length decrease). At a low injection rate, the first pass presents a plateau form. Substantial changes in the gadolinium concentrations during signal acquisition induce artifacts. Furthermore, the haemodynamic parameters (cardiac output, blood pressure) influence the bolus profile. The characteristics of gadolinium agents are favorable in the early bolus phase, whereas the advantages of large complexes (e.g. blood pool agents) and ultrasmall superparamagnetic iron oxide (USPIO) are most evident in the distribution phase.

The company is a member of the Bracco Group, a highly innovative healthcare group and world leader in global integrated solutions for the diagnostic medical imaging field. The Bracco Group is headquartered in Milan, Italy. Its North American operations consist of Bracco Diagnostics and Bracco Research USA, both located in Princeton, New Jersey. Bracco Diagnostics is one of the fastest growing developers and marketers of diagnostic pharmaceuticals in North America, with products for various imaging applications, including Isovue® (iopamidol - X-ray contrast agent), ProHance® (gadoteridol - MRI contrast agent), SonoVue® (ultrasound contrast agent) and nuclear medicine products.
Gadoteridol has been available in Europe and the USA for several years. Holder of the Marketing Authorization: Bracco International B.V. - Strawinskylaan 3051 - 1077 ZX Amsterdam The Netherlands. (Contact: Kirk Deeter, Phone: +NL-303-838-8708)

MRI Contrast Agents:

This method synchronize the heartbeat with the beginning of the TR, whereat the r wave is used as the trigger. Cardiac gating times the acquisition of MR data to physiological motion in order to minimize motion artifacts. ECG gating techniques are useful whenever data acquisition is too slow to occur during a short fraction of the cardiac cycle.
Image blurring due to cardiac-induced motion occurs for imaging times of above approximately 50 ms in systole, while for imaging during diastole the critical time is of the order of 200-300 ms. The acquisition of an entire image in this time is only possible with using ultrafast MR imaging techniques. If a series of images using cardiac gating or real-time echo planar imaging EPI are acquired over the entire cardiac cycle, pixel-wise velocity and vascular flow can be obtained.
In simple cardiac gating, a single image line is acquired in each cardiac cycle. Lines for multiple images can then be acquired successively in consecutive gate intervals. By using the standard multiple slice imaging and a spin echo pulse sequence, a number of slices at different anatomical levels is obtained. The repetition time (TR) during a ECG-gated acquisition equals the RR interval, and the RR interval defines the minimum possible repetition time (TR). If longer TRs are required, multiple integers of the RR interval can be selected. When using a gradient echo pulse sequence, multiple phases of a single anatomical level or multiple slices at different anatomical levels can be acquired over the cardiac cycle.
Also called cardiac triggering.