SRS
Stereotactic Radiosurgery — single-fraction (or few-fraction, "fractionated SRS") high-precision ablative radiation. Brain metastases, vestibular schwannoma, meningioma, AVM, trigeminal neuralgia, functional disorders. Body-equivalent technique is SBRT.
Three platform classes deliver SRS:
- Linac-based (Varian TrueBeam STx, Edge; Elekta Versa HD) — frameless or framed.
- Robotic (Accuray CyberKnife) — non-coplanar beams, frameless.
- Cobalt sealed-source (Leksell Gamma Knife) — cranial only.
Why it matters to buyers: Capable linac + high dose rate + frame / frameless immobilization. SRS mode on Clinac iX runs at 800 MU/min; modern FFF beams reach 1200–2400 MU/min for shorter delivery.
Why it matters to engineers: Sub-millimeter precision. Dedicated commissioning + TG-142 subsection. End-to-end SRS test (imaging + couch + delivery + dose) is the accreditation gate.