Eclipse (radiotherapy)

Eclipse (radiotherapy)
Name	Eclipse
Caption	Varian Eclipse treatment planning system
Manufacturer	Varian Medical Systems
Introduced	1990s
Type	Radiotherapy treatment planning system

Eclipse (radiotherapy) is a commercial radiotherapy treatment planning system developed by Varian Medical Systems used for designing radiation therapies for cancer patients. It integrates imaging, dosimetry, optimization, and beam modeling to generate patient-specific plans for modalities such as intensity-modulated radiotherapy, volumetric modulated arc therapy, and stereotactic treatments. Eclipse interfaces with linear accelerators, imaging platforms, and oncology information systems to support multidisciplinary cancer centers and radiation oncology clinics.

Overview

Eclipse is a software platform that performs dose calculation, inverse planning, and plan evaluation for external beam radiotherapy and brachytherapy, and links with devices from vendors like Varian Medical Systems, Elekta, Accuray, Siemens Healthineers, and Philips. It supports imaging modalities including Computed tomography, Magnetic resonance imaging, and Positron emission tomography for target delineation and image fusion, and interoperates with oncology workflows in systems such as Mosaiq and ARIA. Eclipse implements algorithms for heterogeneity correction, grid-based dose calculation, and multi-criteria optimization to meet clinical protocols from institutions like MD Anderson Cancer Center, Memorial Sloan Kettering Cancer Center, Mayo Clinic, and Royal Marsden Hospital.

History and Development

Eclipse originated in the 1990s amid rapid computerization of radiation oncology alongside contributions from companies and research centers including Varian Medical Systems, Stanford University, University of Michigan, and industrial partners in Palo Alto. As radiotherapy advanced through milestones like the introduction of multileaf collimator technology, three-dimensional conformal radiotherapy, and intensity-modulated radiotherapy, Eclipse evolved to incorporate inverse planning engines, model-based dose calculation, and later grid-based Boltzmann solvers influenced by academic work at Massachusetts Institute of Technology, Johns Hopkins University, and Duke University. Regulatory clearances and commercialization interacted with standards from bodies such as U.S. Food and Drug Administration, European Medicines Agency, and professional societies including American Society for Radiation Oncology and European Society for Radiotherapy and Oncology.

Technology and Components

Eclipse comprises modules for image import, contouring, beam modeling, optimization, and dose calculation. Core components include the Treatment Planning System (TPS) kernel, the optimization engine, and dose engines like the anisotropic analytic algorithm and Acuros XB photon solver developed with physics efforts from groups at University of Wisconsin, University of Pennsylvania, and commercial research teams at Varian Medical Systems. It supports beam models for linear accelerators by vendors such as Varian Medical Systems and Elekta, and interfaces with immobilization and localization technologies from companies like Brainlab and CIVCO Radiotherapy. The software integrates with image registration tools used at centers such as Royal Marsden Hospital and MD Anderson Cancer Center and uses DICOM standards promoted by National Electrical Manufacturers Association and Integrating the Healthcare Enterprise.

Clinical Applications

Clinicians use Eclipse to plan treatments for malignancies in sites treated at institutions like Memorial Sloan Kettering Cancer Center, MD Anderson Cancer Center, Royal Marsden Hospital, and Princess Margaret Cancer Centre. Common clinical applications include head and neck cancer protocols developed at MD Anderson Cancer Center, prostate cancer regimens from Memorial Sloan Kettering Cancer Center, lung cancer strategies from Royal Marsden Hospital, and stereotactic radiosurgery approaches refined at UCSF Medical Center and Stanford Health Care. Eclipse supports specialized workflows for pediatric oncology practiced at Great Ormond Street Hospital and complex reirradiation cases managed at referral centers including Mayo Clinic.

Treatment Planning and Workflow

Typical workflows in oncology departments such as Johns Hopkins Hospital, Cleveland Clinic, and Mount Sinai Hospital include CT simulation, image fusion with Magnetic resonance imaging or Positron emission tomography, contouring by radiation oncologists, optimization by medical physicists, and plan review by multidisciplinary tumor boards akin to practices at Memorial Sloan Kettering Cancer Center. Eclipse enables inverse planning for intensity-modulated radiotherapy and VMAT with constraints informed by dose–volume histogram criteria used by American Society for Radiation Oncology, and plan export to record-and-verify systems like ARIA and Mosaiq for delivery on linear accelerators built by Varian Medical Systems or Elekta.

Quality Assurance and Safety

Quality assurance routines adopted in centers such as MD Anderson Cancer Center, Mayo Clinic, and Royal Marsden Hospital include patient-specific dose verification, independent secondary calculations, end-to-end tests with anthropomorphic phantoms from groups like Radiological Society of North America, and commissioning protocols guided by reports from American Association of Physicists in Medicine and International Commission on Radiation Units and Measurements. Safety depends on software validation, beam model commissioning for machines from Varian Medical Systems and Elekta, and workflow checks integrated with oncology information systems used at institutions such as Mount Sinai Hospital and Cleveland Clinic.

Limitations and Future Directions

Limitations of Eclipse reflect general TPS challenges encountered at research sites like Massachusetts Institute of Technology and Stanford University: computational cost for Monte Carlo–grade accuracy, uncertainties in deformable image registration studied at Johns Hopkins University, and integration of functional imaging biomarkers from MD Anderson Cancer Center. Future directions involve AI-driven auto-contouring research from companies and labs collaborating with University of Toronto and Imperial College London, adaptive radiotherapy trials at Memorial Sloan Kettering Cancer Center and MD Anderson Cancer Center, cloud-based planning initiatives influenced by providers like Google Health and Microsoft, and harmonization with international standards from International Atomic Energy Agency and World Health Organization.

Category:Radiation therapy