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The QT Scanner 2000 Model A is for use as an ultrasonic imaging system to provide reflection-mode and transmissionmode images of a patient's breast. The QT Scanner 2000 Model A software also calculates the breast fibroglandular tissue volume (FGV) value and the ratio of FGV to total breast volume (TBV) value as determined from reflection-mode and transmission-mode ultrasound images of a patient's breast. The device is not intended to be used as a replacement for screening mammography.

The QT Scanner 2000 Model A is indicated for use by trained healthcare professionals in environments where healthcare is provided to enable breast imaging in adult patients.

The QT Scanner 2000 Model A ("QT Scanner") is an automated, software-controlled ultrasound imaging system which performs a standardized scan of the whole breast without the use of ionizing radiation, compression, or contrast injection; and generates both reflection-mode and transmission-mode breast images. The QT Scanner consists of a Patient Scanning System, an Operator Console, an optional offboard image processor, and the OTviewer software.

The Patient Scanning System contains the necessary electronics which perform acquisition and initial processing of the breast images and further provides a support table which allows the patient to rest comfortably while the scanning takes place. The scan tank is centered below a patient's breast and contains the ultrasound transducer arrays. The transducer arrays include a set of three reflection transducers that transmit pulsed ultrasound plane waves into targeted tissues using the water bath in the scan tank as a coupling medium. An additional transmitter and receiver array pair collect the ultrasound energy to provide speed of sound values.

During scanning, a patient lies prone on the examination table with the breast suspended in a warm water bath maintained near skin temperature. Images are automatically acquired on a pendant breast positioned with the nipple as a point of reference. The transducer arrays rotate about a vertical axis to circle the breast in the coronal plane. The array is then translated vertically, and the scanning process is repeated until the entire breast is scanned, allowing B-scan images to be constructively combined into tomographic, speed of sound and reflection ultrasound images.

The QT Scanner outputs the images to a server which allows the images to be stored until they are reviewed on a Viewer Console running the QTviewer™ software. Alternatively, raw data files can be output to a server and remotely constructively combined into tomographic, speed of sound and reflection ultrasound images. Coronal, axial and sagittal images are generated for review by the radiologist. The QTviewer software also provides a number of analytics capabilities, such as biometric measurement, manual segmentation, and Region of Interest calculations. The QTviewer software also provides the "Fibroglandular Volume" (FGV) which is display of calculated fibroglandular tissue volume within a breast, expressed in dimensions of volume, as well as a ratio of the volume of fibroglandular tissue within the breast volume to the total breast volume, from QT Scanner breast images.

The QTviewer software also provides the "Fibroglandular Volume" (FGV) which is display of calculated fibroglandular tissue volume within a breast, expressed in dimensions of volume, as well as a ratio of the volume of fibroglandular tissue within the breast volume to the total breast volume (TBV), provided as FGV/TBV. The process for calculating FGV and FGV/TBV is based on image segmentation methods. The first step is segmentation of the whole breast from the surrounding water. Attenuation images are used to identify the boundary of the breast assuming that attenuation anywhere outside the breast (within water) is essentially zero. From skin inward, every pixel is labelled as breast tissue. The next step identifies the pixels in the vicinity of the boundary as border pixels and which constitute the skin of the breast. The pixels labelled as surrounding water and skin are removed from the breast and the remaining breast volume is deemed as TBV. In the next step, pixel values from the segmented speed of sound image are provided to a one-dimensional fuzzy c-means (FCM) algorithm to partition of data set into two clusters: fibroglandular tissue and fat. Once FCM is trained, a membership map of fibroglandular tissue is generated and an empirically chosen threshold is applied to binarize the fibroglandular tissue membership map which constitutes fibroglandular tissue volume (FGV). The ratio of FGV to TBV (FGV/TBV) is then calculated by dividing the volume of the fibroglandular tissue by the volume of the whole breast.

The provided text describes the 510(k) premarket notification for the QT Scanner 2000 Model A. The key difference between the subject device and its predicate is the addition of an automated calculation of breast fibroglandular tissue volume (FGV) and the ratio of FGV to total breast volume (TBV). The information for describing acceptance criteria and the study that proves the device meets them primarily relates to this new FGV/TBV feature.

Here's a breakdown of the requested information based on the provided text:

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

The document does not explicitly state numerical acceptance criteria for the FGV/TBV calculation. Instead, it describes demonstrating "strong correlation" with breast MRI as the performance measure.

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

• Sample Size: 53 breasts from 29 patients.
• Data Provenance: Retrospective study. The country of origin is not specified, but given the FDA submission, it is likely U.S. data or data compliant with U.S. regulatory standards.

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)

The document states that the comparison was made to values "as determined via breast MRI," implying that the MRI values served as the ground truth. However, it does not specify the number of experts or their qualifications used to establish this ground truth from the MRI data.

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

The document does not describe any adjudication method. It simply states that the FGV and FGV/TBV values determined by the QT Scanner were compared to those determined by breast MRI.

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. The study described is a direct comparison of the device's numerical output (FGV/TBV) against breast MRI, not a human-in-the-loop study assessing reader performance improvement with AI assistance.

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

Yes, a standalone performance evaluation was done for the FGV/TBV calculation capability. The study directly compared the algorithm's output (FGV and FGV/TBV) with values derived from breast MRI, without human intervention in the calculation process.

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

The ground truth used was values determined via breast MRI. This is a clinical imaging modality, not explicitly expert consensus from multiple readers, pathology, or outcomes data.

8. The sample size for the training set

The document does not specify the sample size for the training set used for the FGV/TBV calculation algorithm. The study described is a retrospective clinical validation study for the algorithm's performance, not a description of its development or training.

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

The document does not describe how the ground truth for the training set was established, as it focuses on the clinical validation study.

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The QT Scanner 2000 Model A is for use as an ultrasonic imaging system to provide reflectionmode and transmission-mode images of a patient's breast. The device is not intended to be used as a replacement for screening mammography.

The QT Scanner 2000 Model A ("QT Scanner") is an automated, software-controlled ultrasound imaging system which performs a standardized scan of the whole breast without the use of ionizing radiation, compression, or contrast injection; and generates both reflection-mode and transmission-mode breast images. The QT Scanner consists of a Patient Scanning System, an Operator Console, an optional offboard image processor, and the QTviewer software.

The Patient Scanning System contains the necessary electronics which perform acquisition and initial processing of the breast images and further provides a support table which allows the patient to rest comfortably while the scanning takes place. The scan tank is centered below a patient's breast and contains the ultrasound transducer arrays. The transducer arrays include a set of three reflection transducers that transmit pulsed ultrasound plane waves into targeted tissues using the water bath in the scan tank as a coupling medium. An additional transmitter and receiver array pair collect the ultrasound energy to provide speed of sound values.

During scanning, a patient lies prone on the examination table with the breast suspended in a warm water bath maintained near skin temperature. Images are automatically acquired on a pendant breast positioned with the nipple as a point of reference. The transducer arrays rotate about a vertical axis to circle the breast in the coronal plane. The array is then translated vertically, and the scanning process is repeated until the entire breast is scanned, allowing B-scan images to be constructively combined into tomographic, speed of sound and reflection ultrasound images.

The QT Scanner outputs the images to a server which allows the images to be stored until they are reviewed on a Viewer Console running the OTviewer™ software. Alternatively, raw data files can be output to a server and remotely constructively combined into tomographic, speed of sound and reflection ultrasound images. Coronal, axial and sagittal images are generated for review by the radiologist. The QTviewer software also provides a number of analytics capabilities, such as biometric measurement, manual segmentation, and Region of Interest calculations.

The provided text describes two clinical studies that support the substantial equivalence of the QT Scanner 2000 Model A to its predicate device. Both studies evaluate features of the device's software.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

The FDA clearance document does not explicitly state quantitative acceptance criteria in the typical format (e.g., AUC > X, Sensitivity > Y). Instead, it describes performance in comparative terms. The acceptance criteria appear to be based on demonstrating superiority or non-inferiority compared to the default processing method, as interpreted and evaluated by expert radiologists.

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

• Study 1 (Implant Processing): 25 breast with silicone implant images.
• Study 2 (Transmission- and Reflection-mode Reprocessing): 25 challenging-case breast images (13 dense breasts and 12 fatty breasts).
• Data Provenance: Both studies used "previously-acquired QT Ultrasound breast images," indicating a retrospective data collection. The country of origin is not specified.

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

• Number of Experts: Three (3) expert radiologists for each study.
• Qualifications: Referred to simply as "expert radiologists." No further details on their experience (e.g., years of experience, sub-specialty) are provided in this document.

4. Adjudication Method for the Test Set

The document states that "three (3) expert radiologists independently reviewed" the images. The images were reviewed "in a blinded manner" and "comparatively evaluated." This suggests an independent review process, but it does not specify an adjudication method like 2+1 or 3+1 for resolving discrepancies. The reported performance implies a consensus or agreement was reached, or that individual findings were statistically aggregated, but the exact method isn't detailed.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size

These studies were multi-reader multi-case (MRMC) studies, as they involved multiple expert readers evaluating multiple cases.

• Effect Size: The document describes the effect qualitatively (e.g., "superior overall interpretability," "non-inferior visualization") rather than providing specific quantitative effect sizes (e.g., percentage improvement in detection rate, change in diagnostic accuracy metrics).

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

No, these studies primarily evaluated the effect of the software's processing features on human interpretation. The experts reviewed the images generated by the different processing methods to assess interpretability and visualization. This is not a standalone algorithm performance evaluation where the algorithm makes a diagnosis without human input.

7. The Type of Ground Truth Used

The "ground truth" for assessing the interpretability and visualization of the images was based on expert visual grade analysis by three independent expert radiologists. This is a form of expert consensus or subjective expert evaluation of image quality and feature visualization, rather than an objective "ground truth" like pathology results or outcomes data that define the presence or absence of a disease.

8. The Sample Size for the Training Set

The document does not provide information on the sample size used for the training set for the software algorithms. The clinical studies described are performance evaluations of the software output using retrospective test sets.

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

Since information on the training set and its size is not provided, how its ground truth was established is also not specified in this document.

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