Elekta Precise Treatment System

Family: Elekta (legacy) · Modality: Linear Accelerator

Elekta's mid-1990s-through-early-2000s linear accelerator platform — the Precise Treatment System was Elekta's mainstream clinical linac during the era that Varian dominated with the Clinac C-series / EX-series. Precise evolved out of the earlier Elekta SL-series (SL15 / SL20 / SL25 / SL75) accelerators and introduced digital gantry control, integrated MLC support, and the workflow architecture that later informed Synergy. Large international installed base (Elekta's share is historically higher in Europe and Asia than in the US); still in service at many departments.

Platform highlights

Dual or single-energy photon configurations — 6 MV-only, 6 + 10 MV, or 6 + 15 MV depending on order. Higher-energy (18 MV) configurations existed on select Precise models but were less common than on Varian's 23EX.
Electron energy suite — typical 4 / 6 / 8 / 10 / 12 / 15 / 18 MeV offerings depending on configuration.
Elekta MLCi multileaf collimator — Elekta's first-generation MLC integrated into the Precise head. 40 leaf pairs, 10 mm projected leaf width at isocenter. Contrast the Millennium 120 (5 mm central leaves) — Elekta's 10 mm MLCi is coarser for fine-field IMRT / SRS work.
Magnetron RF source on many Precise configurations — Elekta's historical preference for magnetrons (vs Varian's klystron); magnetrons run at lower peak power but have simpler service patterns.
Agility MLC retrofit path — some Precise installations have been upgraded with the 160-leaf Agility MLC (5 mm leaves at isocenter), extending their IMRT/VMAT capability.
Digital gantry control — Precise introduced the digital-controller architecture that carried forward to Synergy.

Specs

Single or dual photon energies (6 / 6+10 / 6+15 MV typical)
Electron energies 4–18 MeV (configuration-dependent)
Elekta MLCi 10 mm leaves (40 pairs) — Agility 5 mm 160-leaf retrofit possible
Magnetron RF source on most configurations
100 cm SID · ±180° gantry rotation
Digital controller

Clinical positioning

3D-CRT — the clinical workhorse use case.
IMRT — supported on 10 mm MLCi with modulation limitations vs 5 mm MLCs; upgraded Precise units with Agility achieve 5 mm resolution.
Conventional radiation therapy across common indications.
Not SRS-optimized — Elekta's SRS-focused sibling is Synergy S with the 4 mm Beam Modulator; Precise is not the SRS platform.

Service reality

Magnetron is the primary wear item (on magnetron configurations). Magnetron replacement is routine but predictable.
MLC service — MLCi 10 mm leaves; Agility-retrofit units have different service patterns.
Waveguide vacuum and SF6 dielectric management.
Controller software — Precise-generation software has aged; some Precise installations have been controller-upgraded to Synergy-generation software.
TG-142 commissioning and periodic QA per AAPM professional-society guidance (TG-142).

Market position

Large international install base — particularly in Europe and Asia where Elekta's share is historically strong.
Mature refurb market — Precise remains actively traded; service ecosystem is developed.
Upgrade pathway — Synergy / Synergy S → Versa HD (current flagship) → Infinity.

Relationship to siblings and successors

Elekta SL Series (SL15, SL20, SL25, SL75) — predecessor-class (System Cards planned).
Elekta Synergy — successor-class with integrated cone-beam CT for IGRT.
Elekta Synergy S — SRS-focused Synergy variant with Beam Modulator.
Elekta Versa HD — current clinical flagship.
Elekta Infinity — current linear accelerator platform.