{"entity":{"id":"rotating-gamma-radiosurgery-systems","kind":"technology","name":"Rotating gamma and hybrid cobalt systems (Our United TaiChi, MASEP Infini, Akesis Galaxy, GammaPod)","aka":["Rotating gamma system","TaiChiB","TaiChiC","MASEP Infini","Akesis Galaxy","GammaPod"],"tldr":"Cousins of the Gamma Knife that spin a smaller number of cobalt-60 sources around the head or body, some built into the same gantry as a linear accelerator. Several were developed in China and are cleared in the United States.","summary":"The Gamma Knife focuses about two hundred fixed cobalt sources; rotating gamma systems spin fewer sources so their beams cross at the target. Our Scientific's OUR Rotating Gamma System was cleared in 1997 (K970647) and MASEP's Infini in 2011 (K102533). Our United Corporation of Xi'an holds three clearances: TaiChiA, a kV image-guided linac (K193207, 2020); TaiChiC, a cobalt-60 rotating gamma unit (K203250, 2021); and TaiChiB (K210921, 2021), which its 510(k) says \"integrates medical linear accelerator technology and rotating gamma technology\" in one gantry and which also carries an NMPA registration. Akesis's Galaxy (K190844, 2019) and Xcision's GammaPod for breast (K172706, 2017) are other cobalt designs in the FDA database.\n\nThese units trade the Gamma Knife's fixed geometry for body treatment or a combined linac, and the cobalt sources still decay and must be replaced and secured. Peer-reviewed comparisons with linac or Gamma Knife radiosurgery are few; their current market status outside China was not confirmed.","status":"established","asOf":"2026-11-04","links":[{"label":"FDA 510(k) K970647: OUR Rotating Gamma System (20 May 1997)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K970647"},{"label":"FDA 510(k) K102533: Rotating Gamma System Infini (22 March 2011)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K102533"},{"label":"FDA 510(k) K193207: TaiChiA (7 August 2020)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K193207"},{"label":"FDA 510(k) K203250: TaiChiC (12 March 2021)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K203250"},{"label":"FDA 510(k) K210921: TaiChiB (2 November 2021)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K210921"},{"label":"FDA 510(k) K190844: Akesis Galaxy (2019)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K190844"},{"label":"FDA 510(k) K172706: Xcision GammaPod (2017)","url":"https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm?ID=K172706"}],"tags":["machines-wave3"],"related":[],"cancers":["secondary-brain-tumours","breast-cancer","nsclc"],"sections":["radiation","devices"],"technologies":["gamma-knife","radiosurgery-srs","cobalt-60-teletherapy","sbrt"],"targets":[],"drugs":[],"companies":["our-united","masep"],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"provenance":{"editedBy":"OnCo machines inventory (openFDA, accessdata.fda.gov, ClinicalTrials.gov v2, Europe PMC, maker pages)","editedOn":"2026-11-04"},"principle":"A set of cobalt-60 sources rotates on a ring so that their beams overlap at the isocentre, giving a steep dose gradient; hybrid designs mount a linac on the same gantry.","strengths":["Steep dose fall-off from crossing beams","Hybrid units combine radiosurgery and conventional treatment","Lower-cost designs made in China"],"limitations":["Radioactive sources decay, need replacement and security","Few comparative studies","Market status outside China not confirmed"],"since":1997},"route":"/technologies/rotating-gamma-radiosurgery-systems/","neighbours":{"cancer":[{"id":"secondary-brain-tumours","kind":"cancer","name":"Brain metastases (secondary brain tumours)","route":"/cancers/secondary-brain-tumours/"},{"id":"breast-cancer","kind":"cancer","name":"Breast cancer (all types)","route":"/cancers/breast-cancer/"},{"id":"nsclc","kind":"cancer","name":"Non-small-cell lung cancer","route":"/cancers/nsclc/"}],"section":[{"id":"devices","kind":"section","name":"Devices & Physical Therapies","route":"/fronts/devices/"},{"id":"radiation","kind":"section","name":"Radiation Therapy","route":"/fronts/radiation/"}],"technology":[{"id":"cobalt-60-teletherapy","kind":"technology","name":"Cobalt-60 teletherapy","route":"/technologies/cobalt-60-teletherapy/"},{"id":"gamma-knife","kind":"technology","name":"Gamma Knife","route":"/technologies/gamma-knife/"},{"id":"sbrt","kind":"technology","name":"SBRT / SABR (stereotactic radiotherapy)","route":"/technologies/sbrt/"},{"id":"radiosurgery-srs","kind":"technology","name":"Stereotactic radiosurgery (Gamma Knife, CyberKnife, linac SRS)","route":"/technologies/radiosurgery-srs/"}],"company":[{"id":"masep","kind":"company","name":"MASEP Medical Science and Technology Development (Shenzhen)","route":"/companies/masep/"},{"id":"our-united","kind":"company","name":"Our United Corporation","route":"/companies/our-united/"}],"roadmap":[{"id":"linac-machines-roadmap","kind":"roadmap","name":"Linear accelerator machines: from Clinac to AI-imaging linacs, rings and radiosurgery units","route":"/roadmaps/linac-machines-roadmap/"}]}}