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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 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. The product can only be used with photons (high energy x-rays) and cannot be used with electron or proton therapy. This product does not provide any quality assurance that the fields are in fact 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.

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 calculated dose to the patient from the measured radiation fields that is intended to be used as a quality control tool tothen be compared to the intended planned dose. This product is to be used as a quality control check for the treatment planning system and delivery system. Dosimetry Check is not a treatment planning system. It does not design or transmit instructions to a delivery device, nor does it control any other medical device. Being a software only quality control tool, Dosimetry Check never comes into contact with patients or persons. Dosimetry Check is an analysis tool meant solely for quality assurance purposes when used by trained medical professionals.

The provided text describes information about the Dosimetry Check Version 5 Release 1 device, but it lacks the specific details required to fully address your request regarding acceptance criteria and a detailed study. The document is a 510(k) summary for FDA clearance, which typically focuses on demonstrating substantial equivalence to a predicate device rather than presenting a full clinical study with detailed performance metrics against predefined acceptance criteria.

However, based on the available information, I can extract and infer some details:

1. A table of acceptance criteria and the reported device performance

The document does not explicitly state quantifiable "acceptance criteria" for the device's performance in a table format, nor does it provide a direct comparison against such criteria. The "Testing" section mentions "successful testing was accomplished," implying that whatever internal criteria existed were met. The core "performance" of the device is described in relation to its function: computing dose distribution and comparing it to the plan dose, and using a new Convolution/Superposition "Collapsed Cone" Algorithm (CC).

The closest to a performance statement is from the "Conclusion": "The successful testing demonstrates the safety and effectiveness of the Dosimetry Check Version 5 Release 1 when used for the defined indications for use demonstrates that the device for which this 510(k) is submitted perform as well as or better than the legally marketed predicate devices." This is a general statement of equivalency rather than specific performance metrics.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The document does not specify the sample size of the test set used for the internal testing. It also does not provide any information about the data provenance (e.g., country of origin, retrospective or prospective nature).

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

This information is not provided in the document. The device is intended to be used by an "experienced radiological physicist," but there's no mention of experts involved in establishing ground truth for the testing.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

This information is not provided in the document.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

A MRMC comparative effectiveness study was not explicitly mentioned or described. The device is "standalone software" for quality control and does not appear to involve human readers in an AI-assisted diagnostic capacity. Its function is to check dose distribution, not to interpret images or assist human readers in diagnosis.

6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done

Yes, a standalone performance assessment was done. The "Testing" section clearly states: "Testing consisted of internal testing with and without the Graphic Processing Unit for the comparison of the results obtained using the Pencil Beam (PB) algorithm in the 510(k) cleared version of Dosimetry Check to the results obtained using the Convolution/Superposition 'Collapsed Cone' Algorithm (CC) added in Dosimetry Check Version 5 Release 1 as well as regression testing." This indicates the algorithm's performance was evaluated independently.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The document does not explicitly state the "ground truth" used for testing. However, given the device's function of calculating and comparing dose distributions, the ground truth would likely be established through:

• Physics-based calculations: Comparison against established physics models or highly accurate, independently verified dose calculation systems.
• Known measured radiation fields: Using precisely measured radiation fields to simulate and verify the accuracy of the computed dose.
• Comparison against predicate device results: The testing involved comparing results with the previously cleared version of Dosimetry Check (using the Pencil Beam algorithm) and the new Collapsed Cone algorithm. The predicate device's output would serve as a reference in this context.

8. The sample size for the training set

The document does not specify a training set sample size. This type of device (a dose calculation algorithm for quality control) might not involve a "training set" in the machine learning sense, but rather a set of test cases designed to validate the accuracy of its physics-based calculations.

9. How the ground truth for the training set was established

Not applicable, as a training set or its associated ground truth establishment is not discussed in the provided text.

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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.

Here's an analysis of the acceptance criteria and study proving the device meets them, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The provided text does not explicitly state specific numerical acceptance criteria for the Dosimetry Check version 4 release 1. Instead, it relies on demonstrating equivalence to the predicate device and successful external validation. The performance is reported qualitatively.

2. Sample Size Used for the Test Set and Data Provenance

• Sample Size for Test Set: Not explicitly quantifiable from the provided text in terms of individual patient cases or measurements. The external validation was performed at 2 sites in Europe and 3 sites in the US. The text mentions "All aspects of using Dosimetry Check for quality control for TomoTherapy were tested during the beta testing." This suggests a comprehensive evaluation rather than a fixed number of cases.
• Data Provenance (Retrospective/Prospective, Country of Origin): The external validation involved prospective "beta testing" at 2 sites in Europe and 3 sites in the US. It doesn't specify if the data used for internal testing (modular, regression, verification) was retrospective or prospective, or its origin.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

The text does not explicitly state the number of experts used to establish ground truth or their specific qualifications (e.g., "radiologist with 10 years of experience"). It mentions that the device is "intended to be used by an experienced radiological physicist for quality control purposes only." It is implied that these "experienced radiological physicists" at the beta test sites would be the ones evaluating the device's output against their clinical judgment or established facility standards, effectively forming the "ground truth" for the device's utility in their context.

4. Adjudication Method for the Test Set

The document does not specify an adjudication method (e.g., 2+1, 3+1). The "beta testing" implies evaluation by the "intended users" (experienced radiological physicists), but the process of reaching consensus or resolving discrepancies is not described.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

No. A Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This device is a quality control software for dose calculation and comparison, not an AI-assisted diagnostic tool for human readers. It's intended to verify treatment plans, not to assist humans in interpreting images or making diagnoses in the typical MRMC study context. Therefore, there is no discussion of human reader improvement with or without AI assistance.

6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done

Yes, in essence. Dosimetry Check is described as "standalone software" and its primary function is to "compute the dose and dose distribution" and "compare to the plan dose." While it is used by an "experienced radiological physicist," the software itself performs the calculation and comparison autonomously. The physicist then interprets the results. This aligns with the concept of standalone algorithmic performance in its core function. The "Nonclinical Testing" (modular, regression, verification, installation, performance testing) likely evaluated the algorithm's standalone accuracy in these computations.

7. The Type of Ground Truth Used

The ground truth used for assessing the device appears to be the patient-specific radiation treatment plan (planned dose) against which the device calculates and compares a "reconstructed dose" from measured radiation fields. The text states: "...to calculate the reconstructed dose that is then compared to the plan dose." The overall evaluation of performance during external validation would be based on whether the device's output (the comparison) was deemed acceptable and useful by the "experienced radiological physicist" in their quality control workflow.

8. The Sample Size for the Training Set

The document does not explicitly state a sample size for a training set. Given the nature of this software (dose calculation and comparison based on physical principles), it's more likely developed using well-established physics models and possibly calibrated with phantom measurements, rather than being "trained" on a large dataset in the machine learning sense. The kernel for deconvolution in the predicate device (Dosimetry Check version 3) was derived from "phantom measurements," which might be analogous to a calibration or parameter tuning set, but not a typical "training set" for AI.

9. How the Ground Truth for the Training Set was Established

As there's no explicit "training set" mentioned in the context of machine learning, the question isn't directly applicable. However, if we consider calibration or model parameter derivation:

• For the predicate device, the "kernel" used in the deconvolution process was "derived prior from phantom measurements with the same imaging device or media." This suggests the ground truth for these derivations would be known physical properties of phantoms and direct measurements using established dosimetry techniques.
• For the modified device, the extension to TomoTherapy uses a "fan beam radiation detector" and "a prior measured profile in the perpendicular longitudinal direction is then applied to complete the radiation field map." The establishment of these "prior measured profiles" would similarly rely on physical measurements and known ground truth for radiation fields.

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Ask a specific question about this device