systemHitachiOpen Extremity MRIfamily: hitachi-open

Hitachi Oasis 1.2T Open MRI

Manufacturer: Hitachi (imaging business acquired by Fujifilm in 2021) · Modality: Open / Extremity MRI

High-field open MRI — the highest field strength available in an open-architecture MRI scanner. At 1.2 Tesla with a vertical field orientation, Oasis occupies a clinical position that no other platform fills: clinical-grade image quality approaching conventional 1.5T closed-bore systems, on a fully open architecture that addresses claustrophobia, bariatric patients, pediatric / parent-in-room workflows, and interventional access that cylindrical-bore scanners physically cannot accommodate. Hitachi's imaging business (including Oasis) was acquired by Fujifilm in 2021 and integrated into Fujifilm Healthcare; Oasis continues in OEM service under that corporate identity.

Architecture — why 1.2T open is unique

  • 5th-generation Hitachi open-magnet technology — the culmination of Hitachi's open-MRI investment (predecessors: Airis series 0.3T permanent, Altaire 0.7T, etc.).
  • Vertical main field (rather than horizontal as in closed-bore cylindrical systems). The patient lies on a table that passes between two magnet pole faces above and below; there is no tunnel.
  • 270° of unobstructed view for the patient — the magnet structure does not enclose the patient axially.
  • Superconducting magnet with active shielding — despite the open architecture, Oasis uses a superconducting helium-cooled magnet rather than a permanent-magnet design. This is what enables the 1.2T field strength; permanent-magnet open MRIs top out around 0.3–0.4T.
  • Helium refill interval ~2 years — longer than many conventional MRIs due to the active-shielding design.

Platform highlights

  • 1.2 Tesla vertical field.
  • 45 × 45 × 45 cm FOV with OEM-specified homogeneity of 0.3 ppm at 35 cm DSV.
  • 81 cm wide fully-motorized patient table.
  • 660 lb (300 kg) table weight capacity — bariatric-capable.
  • 33 mT/m gradient amplitude · 100 T/m/s slew rate — adequate for routine clinical MRI at 1.2T.
  • 18 kW RF chain.

Specs

  • 1.2 T vertical field · 5th-generation Hitachi open magnet
  • 45 × 45 × 45 cm FOV · 0.3 ppm @ 35 cm DSV homogeneity
  • 81 cm motorized patient table · 660 lb weight capacity
  • 33 mT/m gradient · 100 T/m/s slew
  • 18 kW RF chain
  • Active magnetic shielding · helium with ~2-year refill interval
  • 270° unobstructed patient view

Clinical positioning

  • Bariatric and extremely obese patients — the open architecture and 660 lb table capacity accommodate patients who cannot enter standard 60 cm / 70 cm closed-bore scanners.
  • Claustrophobic patients — the 270° patient view eliminates the tunnel experience that drives MRI intolerance.
  • Pediatric with parent-in-room — parent stays adjacent to the child during the exam.
  • Interventional MR — MR-guided biopsy, aspiration, ablation; the open architecture allows physical operator access during the procedure.
  • Pacemaker / implant patients at higher field — 1.2T covers most MR-conditional implant labeling that is limited to 1.5T and under.
  • Orthopedic specialty imaging — large patient populations in sports-medicine and orthopedic clinics favor the open geometry.

Market position (secondary / refurb)

  • Specialist platform — Oasis has never been a high-volume competitor to closed-bore 1.5T / 3T. Its market is the subset of patients who cannot or will not use conventional MRI, plus the interventional-MR use case.
  • Orthopedic and outpatient imaging clinics are the primary buyers.
  • Service ecosystem — Fujifilm OEM service under the post-2021 ownership; multi-vendor service coverage is developing as the installed base ages.
  • Competing platforms — Siemens MAGNETOM Free.Max (0.55T, 80 cm cylindrical bore) occupies a similar low-field / wide-access niche with a different architectural trade-off; Esaote G-scan Brio (0.25T open weight-bearing) for orthopedic specialty.

Relationship to siblings

  • Hitachi Airis II 0.3T — permanent-magnet open sibling; lower field, no cryogens.
  • Hitachi Altaire 0.7T — predecessor-class mid-field open MRI (System Card planned).
  • Fujifilm Echelon / Echelon Smart — Fujifilm-branded closed-bore MRI platforms; post-2021 combined Fujifilm + Hitachi MRI portfolio (System Cards planned).

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