gradient strength
Magnetic field gradient amplitude, measured in mT/m. Defines how sharply the field varies across space — combined with slew rate (T/m/s), gradient amplitude bounds the platform's achievable spatial resolution and the minimum echo time on advanced sequences. The two specs are quoted together as the platform's gradient envelope.
Why it matters to buyers: Higher gradient strength enables diffusion imaging at high b-values, MR spectroscopy, faster echo-planar sequences, and finer cardiac / fetal / pediatric imaging. Typical tiers:
- ~30 mT/m effective on 1.5T workhorse platforms.
- ~45 mT/m on premium 1.5T (Philips Ingenia, Siemens MAGNETOM Aera high-tier).
- ~80 mT/m on premium 3T (Prisma, Vida, Premier, Ingenia Elition).
- 100–300 mT/m on research / connectome-class systems.
Why it matters to engineers: Gradient amplifier (GPA) drives the gradient coils. Exceeding duty cycle cooks the amplifier or coil; gradient cooling is a top-3 service event on any clinical MRI. Chiller flow alarms = stop scanning — clearing the alarm and continuing risks expensive damage.