MRI Spec Schema

Frontmatter fields every MRI system carries on top of the common system fields.

field_strength_tesla: 1.5
bore_size_cm: 60
magnet_length_cm: 160
gradient_strength_mt_m: 30
gradient_strength_effective_mt_m: 52
slew_rate_t_m_s: 125
slew_rate_effective_t_m_s: 216
rf_channels: 8                  # independent RF receive channels
max_coil_elements: 76           # matrix / TIM total
coil_platform: TIM              # TIM | HD | dStream | matrix | none
helium_refill_required: true    # some newer systems are sealed
shim_type: active               # passive | active
host_computer: syngo MR         # MRI vendor software family
current_at_field: 472           # amps (magnet operating current, if spec'd)
system_weight_kg: 6000
cryogen_type: helium

Rationale

Field strength, bore size, and gradient/slew rate drive the clinical capability and purchase decision. RF channel count and coil platform drive image quality and are what distinguishes a new-generation refurb from a tired one. Cryogen + shim + helium-refill behavior are the real cost-of-ownership items that buyers need to know but OEM spec sheets bury.