Cameras that watch the patient's skin in three dimensions, robotic couches and moulded shells that hold the body still, so each radiotherapy dose lands where the plan says without tattoos and with the beam paused if the patient moves.
Radiotherapy accuracy depends on putting the patient in the same position every day. Immobilisation devices (thermoplastic masks for head and neck and brain, vacuum bags, breast boards, indexed couch tops from Orfit, Qfix and CIVCO) provide the coarse fix. Surface-guided radiotherapy systems then project structured light onto the skin and reconstruct the surface from ceiling cameras many times a second: Vision RT's AlignRT, C-RAD's Catalyst+ and Sentinel, Brainlab's ExacTrac Dynamic (which fuses surface and thermal imaging with stereoscopic X-rays) and Varian's IDENTIFY. The surface is registered to the planned surface to guide set-up, monitor intra-fraction motion and gate the beam, which allows tattoo-free set-up, deep-inspiration breath-hold for left breast cancer, and open-face masks for brain radiosurgery. Six-degree-of-freedom robotic couches correct residual rotations.
The skin is a surrogate: for tumours deep in the body or lying loosely under the surface (prostate, lung, liver) surface position does not guarantee target position, so cone-beam CT or fiducial tracking remains necessary. The systems add capital cost and commissioning effort, and their accuracy depends on camera calibration and on how much skin is exposed.
Structured-light cameras reconstruct the patient's skin surface in real time and register it to the reference surface from planning, driving set-up corrections, motion monitoring and beam gating; rigid immobilisation and robotic couches supply the coarse and rotational corrections.
Surface guidance allowed the face mask to be opened without losing set-up accuracy, and patients tolerated the open masks better. It is a gain in patient experience made possible by precision, rather than a gain in cancer control.
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Query for this technology: (TITLE:"Patient positioning and surface guidance systems" OR ABSTRACT:"Patient positioning and surface guidance systems" OR TITLE:"AlignRT, Catalyst, ExacTrac Dynamic" OR ABSTRACT:"AlignRT, Catalyst, ExacTrac Dynamic") AND (cancer OR tumor OR tumour OR oncology OR carcinoma OR lymphoma OR leukemia OR leukaemia OR myeloma OR sarcoma OR melanoma OR glioma). Results are unfiltered search hits about Patient positioning and surface guidance systems (AlignRT, Catalyst, ExacTrac Dynamic), not a curated reading list.
Shares C-arm medical linear accelerators (TrueBeam, Versa HD and others), Varian (Siemens Healthineers), Head and neck squamous cell carcinoma and the tags machines-wave2, precision.
Shares C-arm medical linear accelerators (TrueBeam, Versa HD and others), Varian (Siemens Healthineers), Head and neck squamous cell carcinoma, IMRT / IGRT (modern external beam) and the tag machines-wave2.
Shares C-RAD, Vision RT, Let the patient see their own breath-hold on a screen or in video glasses, Respiratory gating and tumour tracking systems (RPM, ABC, Calypso, Synchrony) and the tag precision.
Shares In-room imaging for radiotherapy (cone-beam CT, ExacTrac, CT-on-rails, HyperSight), C-arm medical linear accelerators (TrueBeam, Versa HD and others), Head and neck squamous cell carcinoma, IMRT / IGRT (modern external beam) and the tag machines-wave2.
Shares C-arm medical linear accelerators (TrueBeam, Versa HD and others), Varian (Siemens Healthineers), IMRT / IGRT (modern external beam), Breast cancer (all types) and the tag machines-wave2.
Shares C-arm medical linear accelerators (TrueBeam, Versa HD and others), IMRT / IGRT (modern external beam) and the tag precision.
Shares Stereotactic radiosurgery (Gamma Knife, CyberKnife, linac SRS), Head and neck squamous cell carcinoma, IMRT / IGRT (modern external beam) and the tag machines-wave2.
Shares Head and neck squamous cell carcinoma, Breast cancer (all types), Non-small-cell lung cancer and the tag precision.
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