MRI MACHINE

A Magnetic Resonance Imaging (MRI) scan is a non-invasive medical imaging technique that uses strong magnetic fields and radio waves, rather than i...

Key Highlights

Hardware Components
Image Acquisition Parameters
Magnetic Resonance Imaging (MRI)
* Artificial Intelligence (AI) Computed Tomography (CT) Magnetic Resonance Imaging (MRI) * Medical X-rays. Nuclear Medicine.

Features

Hardware Components
Image Acquisition Parameters
Magnetic Resonance Imaging (MRI)
* Artificial Intelligence (AI) Computed Tomography (CT) Magnetic Resonance Imaging (MRI) * Medical X-rays. Nuclear Medicine.

Technical Specifications

Main Magnet	This is the core of the machine, generating a strong, stable, and uniform static magnetic field (B0).
Field Strength	Measured in Teslas (T). Clinical systems typically operate at 1.5 T or 3 T, though systems from 0.2 T up to 7 T are available. Higher field strengths generally provide a greater signal-to-noise ratio (SNR), allowing for higher resolution or faster scans.
Magnet Type	Most high-field clinical magnets are superconducting magnets cooled by liquid helium to maintain zero resistance. Lower-field "open" MRIs may use permanent magnets.
Gradient Coils	Three sets of resistive coils (X, Y, and Z) are located within the main magnet. They create variable magnetic fields that spatially encode the signal, allowing the system to pinpoint the location of the signal origin in the body.
Gradient Strength/Slew Rate	Stronger, faster-switching gradients allow for faster imaging and higher spatial resolution.
RF Coils	These coils transmit RF pulses into the patient to excite the hydrogen protons and also act as receivers to detect the faint energy signals (radio waves) released as the protons return to their equilibrium state.
Receiver Channels	Modern systems may have 32, 64, or more independent receiver channels to enhance signal detection and image resolution.
Computer System	Powerful computers process the raw data from the RF receiver and reconstruct it into detailed cross-sectional "slice" images.
Imaging Sequences (Pulse Sequences)	Different combinations of RF pulses and gradient applications (e.g., T1-weighted, T2-weighted, FLAIR, DWI) produce different tissue contrasts, highlighting various pathologies.
Repetition Time (TR) and Echo Time (TE)	These time parameters determine how much T1 and T2 contrast is present in the final image.
Slice Thickness	This defines the depth of the imaging section. Thinner slices (e.g., <0.5 mm in 2D imaging) offer higher spatial resolution but a lower SNR.
Field of View (FOV) and Matrix Size	These parameters, along with slice thickness, determine the size of the voxels (3D pixels) and thus the spatial resolution of the image.
Signal	to-Noise Ratio (SNR): A key metric for image quality. Higher SNR can be achieved with higher magnetic field strength, larger voxel sizes, or increased scan averages (NEX/NSA), though this often increases scan time.