Understanding Magnetic Resonance Imaging (MRI)
MRI uses powerful magnets and radio waves to create detailed images of organs and tissues. Unlike CT scans, MRI doesn't use ionizing radiation, making it ideal for many diagnostic applications.
How MRI Works
- A powerful magnet aligns hydrogen atoms in the body
- Radio frequency pulses disturb this alignment
- As atoms return to alignment, they emit signals
- These signals are processed to create detailed images
MRI Field Strengths
- 0.2-0.5T (Low-field): Open MRI designs, good for claustrophobic patients
- 1.5T: Standard workhorse for most clinical applications
- 3T: Higher resolution for neurological and research imaging
- 7T: Ultra-high field for specialized research
Understanding CT (Computed Tomography)
CT scanners use X-rays and computer processing to create cross-sectional images of the body. Modern multi-slice CT scanners can capture detailed 3D images in seconds.
CT Scanner Types
- 4-16 Slice: Basic diagnostic imaging
- 32-64 Slice: Standard for most hospitals
- 128+ Slice: Cardiac CT and advanced applications
- Dual-Source CT: Ultra-fast imaging, reduced motion artifacts
When to Choose MRI vs CT
| MRI Best For | CT Best For |
|---|---|
| Brain and spinal cord | Chest and lung imaging |
| Joints and soft tissue | Bone fractures |
| Cardiac structure | Emergency trauma |
| Pediatric imaging | Abdominal pain evaluation |
Sunrays Image Technology offers a wide range of refurbished MRI and CT systems from leading manufacturers like Siemens, GE, and Philips.
