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Dosimetry Check is a standalone software product intended to be used by an experienced radiological physicist for quality control purposes only. Dosimetry Check is intended to check the correctness of x-ray treatment plans delivered from high energy charged-particle radiation therapy treatment machines by using a measurement of the applied radiation fields that are planned to be or have been applied to a patient, and computing the dose to the patient from the measured radiation fields. This product is to be used as a quality control check for the treatment planning system and delivery system. Dosimetry Check quality control software uses the radiation fields that are measured with media such as x-ray film, electronic portal imaging devices (EPID), diode or ion chamber arrays, or in the case of TomoTherapy, a fan line detector array, and provides a theoretical calculation. Dosimetry Check computes the dose and dose distribution using the patient specific CT or other image set or alternately a phantom that is likewise scanned. to calculate the reconstructed dose that is then compared to the plan dose. The results reported can include the computed percent difference at specific points as compared to the patient specific radiation treatment plan. Dosimetry Check does not provide any conclusions regarding the comparisons and does not provide any criteria to be used for interpreting the results. The experienced radiological physicist can reevaluate his patient specific radiation treatment plan in accordance with his clinical judgment. This product is not a treatment planning system and is not to be used as one. This product only checks the applied dose based on the measurement of each x-ray field applied to the patient and provided in an exported file, and a theoretical calculation. This product does not provide any quality assurance that the fields are in fact correctly applied to and correctly aligned with the patient anatomy as planned. In addition. the product may be used to display the above dose on other fused image sets which could provide additional supportive quality information to the user regarding the correctness of treatment.

System 2100 for which 510(k) K993530 was cleared by the FDA on December 15, 1999 that is a medical image display system serves as a foundation that provides basic image display functionality for Dosimetry Check. Dosimetry Check is a software program that will compute the dose and dose distribution to the patient from a measurement of the radiation fields that are applied to the patient. The dose so computed serves as a means to verify the correctness of the radiation treatment and to serve as a final sanity check. The radiation fields are measured with media such as x-ray film or electronic devices that will measure over the area of the field, such as electronic portal imaging devices (EPID), or diode or ion chamber arrays. To extend Dosmetry Check to support the TomoTherapy machine, the device uses the data measured by the fan beam radiation detector that is part of the TomoTherapy machine. The detectors capture the radiation intensity periodically at predetermined gantry angles and couch positions. known as control points, from the treatment plan. The detector only measures the intensity across the center of the radiation beam in the transverse plane. A prior measured profile in the perpendicular longitudinal direction is then applied to complete the radiation field map. The radiation field map is then applied as a stationary beam at the center gantry angle and couch position for the integration period (between two control points), from which the dose to the patient is computed. The patient dose is then summed up from all such radiation field maps.

The product is to be used by radiation oncologist, dosimetrist, and radiation therapy physicist to check the correctness of the x-ray treatment fields from high energy treatment machines that are planned to be or have been applied to a patient. This product is to be used in addition to the treatment planning system to provide a means for additional and redundant verification that the plan is in fact successfully accomplished. This product is not a treatment planning system and is not to be used as one. This product only checks the applied dose based on the measurement of each x-ray field and a theoretical calculation. This product does not provide any quality assurance that the fields are in fact correctly applied to and correctly aligned with the patient anatomy as planned. In addition, the product may be used to display the above dose on other fused image sets which could provide additional clinical information to the radiation oncologist regarding the treatment.

Dosimetry Check with Exit Dose is a software program intended to provide a means for testing the dosimetry of radiation therapy treatments applied to a patient using high energy x-rays. This test is performed from measurements made during treatment of the patient by measuring the radiation fields after they have passed through the patient with a suitable imaging device such as an electronic portal imaging device or other measuring devices or media. The following software functions are then performed: 1. The patient's CT scan treatment plan image set is traced to provide the water equivalent path to points on the measured exit dose plane. 2. A deconvolution process is performed with a kernel that is a function of radius and the thickness transversed to convert the exit images back to x-ray intensity in air fluence prior to patient entry. The kernel is derived prior from phantom measurements with the same imaging device or media. 3. The derived in air fluence is now the same starting point as when the radiation fields are measured directly prior to patient entry. 4. The existing Dosimetry Check (FDA 510(k) K010225) software functions are then used to compute the dose to the patient using the in air fluence for each treatment beam and to evaluate the correctness of the dose to the patient.

This product is to be used by radiation therapy oncologist or staff under their direction to locate the position relative to the patient of the isocenter of a treatment beam on a gantry mounted radiation therapy treatment machine. Some internal marker must be visible on both a radiograph of the patient taken at the time of treatment and the images used for the treatment plan in order to use this software to align the marker image on the radiograph with the plan to find the proper patient support system coordinates. Only a translation along the couch lateral, longitudinal, and height directions are considered and solved for. Possible rotations or repositioning of the patient are not considered.

VisiTrak is a radiation therapy localization software system that assist in aiming the radiation beam. This software uses functions from System 2100, a Radiological Image Display System, 510(k) K993530, and Dosimetry Check, a treatment plan delivery testing system, 510(k) K010225. The following functions are included in VisiTrak: - (1) Means to download a treatment plan from a treatment planning system, to include a stackable image set (such as the CT scans used to generate the plan), beam geometry, and optional regions of interest outlines. [This function from Dosimetry Checkl - (2) Means to define and trace a marker that is visible in the stackable image set. [This function from System 2100] - (3) Means to draw the markers on two dimensional plane images and three dimensional perspective room views. - (4) Means to read in radiographic images made of the patient in the treatment position on the gantry mounted treatment machine. - (5) Means to define the geometry for each radiographic image, i.e., in the treatment machine coordinates. - (6) Means to project the defined markers onto the radiographic images. - (7) Means to manually select couch coordinates to match up the images of the markers on the radiographs with the projected marker images. - (8) Means to trace the images of the markers on the radiographs. - (9) Means to solve for the best estimate of the couch coordinates that will align the projected and traced marker images. - Means to display the couch coordinates for each treatment beam using the (10) couch position found in (7) or (9) above.

This product is to be used by radiation therapy oncologist, dosimetrist, and radiation therapy physicist, to plan the treatment with x-rays for patients undergoing radiation therapy for stationary and gantry arc beams. Support is included for field shaping with multi-leaf collimators and auxiliary blocking, and the use of wedges. Electron therapy and intensity modulated radiation therapy is not included in this product.

RtDosePlan is a radiation therapy external beam treatment planning program that supports treatment planning for x-rays only. The following functions are included: 1. Provide means to read in CT scans and form a patient model. 2. Provide means to define a skin boundary. 3. Provide means to convert CT numbers to physical density. 4. Provide means to define a plan that consists of one or more treatment beams. 5. Provide means to define a treatment beam. 6. Provide means to locate isocenter of the treatment beam within the patient model. 7. Provide means to set the gantry, collimator, and couch angles, and to specify a gantry arc rotation. 8. Provide means to specify a wedge. 9. Provide means to shape a field with a multi-leaf collimator. 10. Provide means to shape a field with auxiliary blocking (cerrobend). 11. Provide means to fit a poly-energetic pencil beam algorithm for the purpose of computing the dose. 12. Provide means to compute the dose to the patient model from the specified treatment beams. 13. Provide means to display the dose on 2d planes in the patient model and 3d room views. 14. Provide means to specify a dose prescription and calculate monitor units for each treatment beam. 15. Provide means to outline regions of interest. 16. Provide means to fuse other image sets and transfer outlines and points from the other image set. 17. Provide means to compute and display dose volume histograms.

MillComp is used to manufacture compensators that are designed for radiation therapy treatment beams. MillComp may be used with any system that can design compensators such that the thickness over the area of the beam is specified at some known source to compensator distance in a plane perpendicular to the central axis. The thickness on an evenly spaced grid may be specified on divergent rays or on rays perpendicular to the plane of the compensator which is perpendicular to the central ray. If on divergent rays, the milled surface may be specified as towards the x-ray source or as towards the patient.

MillComp is a program that will write the tool path program to mill radiation therapy compensators on an end mill. Compensators are attenuators that are to be inserted into the x-ray beams for the purpose of modifying the field distribution over the area of the treatment beam. MillComp takes as input a compensator specification. The compensator specification will come from multiple sources, such as current therapy treatment planning systems, and is converted into a standard specification file format that MillComp can read. The conversion programs to read a compensator specification and write out the standard file format will be written on an as need basis according to the customer's needs. MillComp will read the specification file, generate the surface defined in the specification, and compute the tool paths necessary to cut the surface in solid lead, cerrobend, or other material, on a three axis end milling machine.