How is the resolution of Medical MRI Device measured and improved?
Publish Time: 2024-11-05
The resolution of Medical MRI Device is crucial for accurate diagnosis of diseases, and its measurement and improvement involve many aspects.
Resolution measurement
The resolution of Medical MRI Device is mainly measured by spatial resolution. Spatial resolution indicates the smallest detail that can be distinguished in an image, usually in line pairs per centimeter (lp/cm). In high-resolution images, smaller tissue structures can be clearly distinguished, such as tiny blood vessels or nerve fiber bundles in the brain. Another related indicator is contrast resolution, which is the ability to distinguish differences in signal intensity between different tissues. For example, when distinguishing between liver tumors and normal liver tissue, good contrast resolution can more clearly show the boundary of the lesion.
Methods to improve resolution
Magnetic field strength: Increasing the main magnetic field strength is one of the key means. Under high field strength, the precession frequency of hydrogen nuclei increases, and the signal is stronger, thereby improving resolution. For example, a 3.0T Medical MRI Device can obtain more detailed images under the same conditions compared to a 1.5T device, which is more advantageous for observing fine brain structures.
Gradient magnetic field performance: Optimize the intensity and switching rate of the gradient magnetic field. A stronger gradient magnetic field can more accurately locate the imaging object in space, achieve thinner slice selection and smaller voxels, and thus improve resolution. A fast gradient switching rate can shorten imaging time, reduce motion artifacts, and indirectly improve image quality.
RF coil design: Use high-performance RF coils. Multi-channel phased array coils can increase signal reception sensitivity and uniformity, and different types of dedicated coils (such as head coils, heart coils, etc.) can better fit the inspection site and improve local signal strength and resolution. For example, a dedicated heart coil can significantly improve the resolution of heart images and help detect tiny myocardial lesions.
Scan sequence and parameter optimization: Select a suitable scan sequence, such as high-resolution T1WI, T2WI sequences, etc. At the same time, adjust parameters, such as reducing layer thickness, increasing matrix size, extending echo time (TE) and repetition time (TR), etc., but this requires a balance between imaging time and resolution to meet clinical diagnostic needs.
Through the comprehensive application of these methods, the resolution of Medical MRI Device can be effectively improved, providing more accurate and detailed image information for clinical diagnosis.
