(152 days)
ExacTrac is intended to be used to place patients at an accurately defined point within the treatment beam of a medical accelerator for stereotactic radiosurgery or radiotherapy procedures, in order to treat lesions, tumors and conditions anywhere in the body when radiation treatment is indicated. ExacTrac may also be used to monitor the patient position during the treatment.
ExacTrac is a patient positioning and monitoring system providing the following main features: Patient positioning based on comparison between ExacTrac acquired X-ray images and calculated DRR (Digital Reconstructed Radiographs) using data provided by a treatment planning system. Patient positioning based on comparison between a CBCT scan, acquired by a 30 Imaging Device and imported into ExacTrac, and CT data provided by a treatment planning system. Both modalities can be based on: anatomical landmarks or implanted markers. Patient monitoring during treatment.
The provided text doesn't explicitly state quantitative acceptance criteria or a specific study that proves the device meets them with performance metrics. It rather discusses the general clinical evaluation methods used to support the substantial equivalence decision for the ExacTrac system. However, I can extract and organize the available information relevant to your request.
Here's a breakdown based on the provided text:
Acceptance Criteria and Device Performance
The document does not provide a table of precise quantitative acceptance criteria (e.g., specific accuracy thresholds) or corresponding reported device performance values. The clinical evaluation focuses on supporting "substantial equivalence."
Study Information
The document describes the methods used for clinical evaluation rather than a single, detailed study with specific results.
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Table of Acceptance Criteria and Reported Device Performance: This information is not provided in the given text. The document focuses on general methods of clinical evaluation rather than specific numerical acceptance criteria and performance outcomes.
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Sample Size Used for the Test Set and Data Provenance:
- Test Set (Implicit):
- For X-ray images: "Analysis of existing x-ray image datasets acquired with ExacTrac 5.5 during routine clinical use." No specific sample size is given.
- For CBCT datasets: "Analysis of existing CBCT datasets during routine clinical use for retrospective clinical study." No specific sample size is given.
- Data Provenance: The data comes from "routine clinical use," implying it is retrospective and likely from various clinical sites using ExacTrac 5.5. The country of origin is not specified but given the manufacturer (Brainlab AG, Germany), it's plausible the data could be international, including European and potentially US data.
- Test Set (Implicit):
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Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications: This information is not provided in the text. The document does not detail how ground truth was established for the "existing x-ray image datasets" or "existing CBCT datasets."
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Adjudication Method for the Test Set: This information is not provided in the text.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study: There is no indication of an MRMC comparative effectiveness study being performed to assess the effect size of human readers improving with AI vs. without AI assistance. The ExacTrac device is a patient positioning and monitoring system, not primarily an AI-driven diagnostic or interpretation tool that directly assists human readers in making diagnoses.
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Standalone (Algorithm Only Without Human-in-the-Loop Performance) Performance Study: The document describes "Patient positioning based on comparison between ExacTrac acquired X-ray images and calculated DRR" and "Patient positioning based on comparison between a CBCT scan... and CT data." This implies the system (algorithm) performs an alignment task. While these are standalone functions of the algorithm, the text does not quantify or provide the results of a specific standalone performance study in terms of accuracy metrics. The clinical evaluation mentions "Simulated treatment of anthropomorphic human-bone phantoms," which would involve standalone system performance, but again, no quantitative results are given.
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Type of Ground Truth Used:
- For the "Simulated treatment of anthropomorphic human-bone phantoms": The phantom's known anatomical landmarks or implanted markers would serve as a form of ground truth, established by the phantom's design and potentially precise measurements.
- For the "Analysis of existing x-ray image datasets" and "existing CBCT datasets": The text doesn't explicitly state the ground truth establishment method. It's likely that ground truth for alignment tasks would be based on:
- Comparison to calculated DRRs or CT data: The "Indication for use" and "Device description" mention comparing acquired images to DRRs/CT data from a treatment planning system. The treatment planning system's calculated (expected) positions might serve as the reference.
- Anatomical landmarks or implanted markers: The device description explicitly states both modalities can be based on these, which would inherently provide a ground truth for positioning.
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Sample Size for the Training Set: This information is not provided in the text. As ExacTrac is a patient positioning system leveraging image comparison and potentially markers, it's not described as a deep learning or AI system that requires a distinct "training set" in the modern sense. It uses existing image data (DRRs, CTs) and acquired images for comparison.
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How the Ground Truth for the Training Set Was Established: This information is not applicable in the context of the provided text, as a specific "training set" for an AI model is not mentioned. The device's operation is based on comparing acquired patient images to reference images (DRRs, CTs) from a treatment planning system, where the ground truth is implicitly defined by the initial treatment plan or the known positions of markers/anatomy in those reference images.
§ 892.5050 Medical charged-particle radiation therapy system.
(a)
Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons) intended for use in radiation therapy. This generic type of device may include signal analysis and display equipment, patient and equipment supports, treatment planning computer programs, component parts, and accessories.(b)
Classification. Class II. When intended for use as a quality control system, the film dosimetry system (film scanning system) included as an accessory to the device described in paragraph (a) of this section, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.