RT Elements (4.5); (Elements) Multiple Brain Mets SRS; (Elements) Cranial SRS; (Elements) Spine SRS; (Elements) Cranial SRS w/ Cones; (Elements) RT Planning Platform; (Elements) Dose Review; (Elements) Retreatment Review; Elements Segmentation [Cranial , Basal Ganglia, Head & Neck, Pelvic, Spine, Thoracic & Spine, Extracranial] RT; Elements AI Tumor Segmentation RT; Elements SmartBrush [Angio, Spine] RT; Elements Object Management RT

RT Elements 4.5 is a software-based radiation therapy treatment planning system designed for stereotactic radiosurgery (SRS), fractionated stereotactic radiotherapy (SRT), and stereotactic ablative radiotherapy (SABR) of cranial, head and neck, and extracranial lesions. It generates optimized treatment plans and dose distributions for linac-based radiation delivery, incorporating modules for contouring, dose calculation, quality assurance, and retreatment analysis.

The subject device maintains the same software-only architecture, input/output (DICOM-based), and core dose calculation algorithms (Pencil Beam, Monte Carlo, Circular Cone) as the predicate. New additions include SmartBrush contouring tools, Object Management capabilities, AI-powered tumor segmentation using deep learning, interface to Art-Plan third-party contouring, and expanded GUI technology to HTML5. Operating systems supported were streamlined (Windows 10 1507 removed); display resolution now includes FHD option.

Not stated in this summary. The document references internal Brainlab verification and validation processes, integration tests, GUI and unit tests, and phantom measurement comparisons, but does not cite specific ISO, IEC, or ASTM consensus standards.

RT Elements 4.5 demonstrates substantial equivalence because it performs the same radiation therapy planning function with identical indications for use as the predicate (K223279). Both are software-only devices using the same three dose calculation algorithms, DICOM input/output workflows, and supported image modalities (CT, MRI, PET). Performance testing confirms dosimetric equivalence for Elekta and Varian linacs across multiple beam energies, and the new features (AI segmentation, dynamic jaw tracking, collimator optimization) represent incremental enhancements validated against ground truth or predecessor versions without compromising planning safety or accuracy. The intended user profile and clinical workflow remain unchanged.