How to Plan for MRI Installation

An MRI is a crucial diagnostic tool that is used by many types of medical and diagnostic facilities throughout the world. Purchasing an MRI can be an important step for a practice in optimizing its facilities. However, before you order an MRI, there are some important factors to consider so that your MRI installation is safe and efficient.

Patient Safety

Above all else, it is essential to install the MRI in such a way that will minimize risks to patients and personnel.  For this purpose, the American College of Radiology has put out a safety guideline known as the four-zone plan. This plan separates the MRI facility into four distinct parts, the first of which is the entrance zone. Zone II consists of a reception and waiting area, with separate cubicles where patients can change in privacy. The third zone is the control zone, where the computers and controls are located and operated by staff. Zone IV contains the actual MRI machine. All four zones are separated by solid walls with doors that are kept closed as necessary. To optimize safety, the facility should have its four zones planned and set up before MRI installation.

Shielding Requirements

In order for your MRI system to produce high-quality imaging, it is necessary to make sure that your site has the appropriate shielding from magnetic, RF and sound interference. Consult a shielding professional to learn which types of shielding your facility may need and how to install and test any shielding.

Site Location

It is not enough just to have room for your MRI system and the other three rooms you will need. Your building’s location can seriously affect the quality of the imaging you will be able to get; in some cases, even shielding may not effectively protect your MRI from interference. Elevators, traffic and power lines are among the factors that can affect image quality. Before investing in an MRI installation, consult MRI professionals to determine if your current location is appropriate.

While an MRI can be a valuable asset for your facility, proper installation is essential for safety and quality imaging output. When purchasing an MRI, consider all the factors that can affect correct installation.

The Difference Between Open and Closed MRI Scanners

Open and closed MRI systems have both advantages and disadvantages, with the difference stemming from the shape of the magnet configuration of each. Ultimately, the advisability of using either of these scanners will depend on the needs of the specific patient and the diagnostic goals involved. Patients should discuss the pros and cons of open vs. closed MRI with their physicians, who may also consult MRI specialists as needed.

Open MRI Scanners

In an open MRI machine, the magnets used are usually either resistive electromagnets or permanent magnets with a magnetic field strength of about 0.3 Tesla. These magnets are configured in the form of two large horizontal metal discs. These discs are the two poles of the magnet and the patient is placed between them, with the sides remaining open.

The chief advantage of the open vs. closed MRI is the lack of confinement experienced by the patient. Open MRI can be preferable for claustrophobic patients. It is also optimal for some types of joint studies since it offers a greater freedom of movement. Some patients’ size does not allow them to fit into the closed MRI, making the open MRI the only choice for this type of imaging.

Closed MRI Scanners

The more traditional closed MRI scanner uses a tube-shaped container, around which magnets are placed in a closed circle, creating a field strength of up to 1.5 Tesla. Due to this greater field strength, a closed MRI performs its scans faster than an open one. High field superconducting closed MRI scanners are also able to provide better resolution and thinner slices. In some cases, this capability is essential, while other types of imaging studies are adequately performed at lower resolutions. A high field closed MRI is the only machine that can perform MR myelograms, as well as for certain detection methods for early stroke, cartilage degeneration in the knee and subtle multiple sclerosis plaques.

While some kinds of imaging may only be performed using a closed MRI, in other cases the decision between open vs. closed MRI may take into account the patient’s preferences and specific medical needs. Patients should discuss this issue with their physician and radiologist.

Components in an MRI Machine

A magnetic resonance imaging (MRI) machine is a complicated device that relies on a combination of sophisticated technologies for smooth operation. Each component in an MRI machine serves its own unique function. Main examples of these components include:

The Magnet

All MRI machines are built around a powerful magnet that generates a stable magnetic field capable of encompassing an entire human body. Types of these components used by various manufacturers include permanent magnets, resistive magnets and superconducting magnets. Most MRIs contain superconducting magnets.

Gradient Coils

During operation, an MRI must distort the magnetic field in a precise and reliable way in order to produce accurate images. Gradient coils are used for this purpose. Essentially, these coils change the strength of the generated field at various points in patients’ bodies.

Shim Coils

This component is used to make sure that the magnetic field produced for imaging has an overall uniform level of strength. In turn, this uniform strength promotes image accuracy.

Radio Frequency Coils

All MRIs use radio waves to relay the images of each patient’s body. Radio frequency (RF) coils produce the required waves. There are three types of these coils used to send signals into the patient and produce images: head coils, body coils and surface coils.

Computer

A computer controls the commands sent to a magnetic resonance imaging machine, and also controls the power supplies for the gradient coils and the radio frequency transmitter. The same computer receives the raw radio frequency data from each scan and makes a viewable image from that data. In addition, the computer relays the viewable image data to a monitor, as well as to a device that makes film hard copies of each image.

Problems with any one of the components in an MRI machine can degrade the quality of the images produced by scanning. Since such a loss of quality is unacceptable, each machine must undergo periodic inspection.