(22 days)
The HiRise is intended to be used for 3-D imaging of the upper extremities and pelvis of adult and pediatric patients weighing from 40 to 450 lbs.
The device is to be operated in a professional healthcare environment by qualified health care professionals only.
The HiRise is a Cone Beam Computed Tomography Imaging Device that acquires 360-degree rotational projection sequences which are reconstructed into 3D volumetric images of the examined anatomical region. The device uses a gantry assembly, which is comprised of an X- ray source, image detector, and a motorized gantry. The gantry facilitates the acquisition of a full X-ray projection sequence by the acquisition software. For non-weight bearing scans of the lower extremity, a patient positioner accessory allows the patient to sit into a position where he/she can comfortably place his/her anatomy into the imaging bore.
The gantry assembly is mounted on vertical actuators and can travel vertically to capture weight-bearing anatomy at various heights ranging from the feet to the pelvis regions. The HiRise provides total vertical travel of 37 inches to accommodate patients of various sizes. Images produced by the HiRise can be sent electronically to a DICOM complaint image viewing software.
The provided text describes the HiRise, a Cone Beam Computed Tomography (CBCT) X-ray system, and states that it has been determined substantially equivalent to its predicate device, the CurveBeam LineUP.
Here's an analysis of the acceptance criteria and the study information based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the HiRise device are primarily established through its demonstrated substantial equivalence to the predicate device, the CurveBeam LineUP. The reported device performance is presented in the context of this comparison and in studies confirming diagnostic quality and safety.
| Feature / Criteria (Derived from comparison to Predicate) | Acceptance Criteria (Implied by Predicate Performance) | Reported Device Performance (HiRise) |
|---|---|---|
| Indications for Use | 3-D imaging of foot, knee, hand, elbow. | Expands to 3-D imaging of the upper extremities and pelvis of adult and pediatric patients weighing from 40 to 450 lbs. |
| Performance: Datasets of the humerus, elbow, forearm, hand, wrist, pelvis/hip, femur, knee, shin (lower leg or tib/fib) and foot/ankle were reviewed by a board-certified radiologist and found to be of diagnostic quality. | ||
| Patient Weight Range | 50 lbs to 400 lbs | Expands to 40 lbs to 450 lbs. |
| Performance: The increased weight range has been tested and verified by third-party 60601-1 testing. | ||
| Scan Axis | Horizontal and vertical | Horizontal and vertical |
| Performance: Image sequences captured utilizing the gantry in vertical scanning mode were included in the datasets sent to the board-certified radiologist and found to be of diagnostic quality. | ||
| Tube Voltage (CT scans) | 100-120 kVp | 100-130 kVp. |
| Performance: Bench testing determined optimal X-Ray tube voltage for each anatomy and patient size. Higher kVp was determined to be required to clinically image the new anatomy (hips and pelvis). | ||
| Tube Current | 5 mA | 5.5 or 6.5 mA. |
| Performance: Increased tube current was required to provide diagnostic quality image sequences in the new anatomy (hips and pelvis). | ||
| Scan Time (CT) | 21 sec | 26 sec. |
| Performance: HiRise is slightly slower to allow for greater exposure time required for the denser anatomy. Image quality performance was verified with Bench Testing. | ||
| Image Detector | CMOS flat panel | Amorphous Silicon flat panel. |
| Performance: Detector performance testing verified image quality met requirements. Performance testing demonstrated that the image quality of the amorphous silicon flat panel is statistically equivalent to that of the predicate. | ||
| 3D Imaging Volume | 20cm (high) x 35 cm (diameter) | Large FOV: 8" (20cm) height x 16" (40cm) diameter; Medium FOV: 8" (20cm) height x 10" (25cm) diameter. |
| Performance: Image sequences captured utilizing both volumes were included in the datasets sent to the board-certified radiologist and found to be of diagnostic quality. | ||
| Typical Resolution | 0.3 mm voxel | LFOV: 0.3mm, MFOV: 0.25mm. |
| Performance: Image sequences captured utilizing both volumes, and subsequent resolutions, were included in the datasets sent to the board-certified radiologist and found to be of diagnostic quality. | ||
| Image Quality (Overall) | Diagnostic quality (Implied by predicate) | Performance: Image quality phantoms were scanned in the HiRise and evaluated by a medical physicist. The scans were reviewed by a radiologist and found to be of diagnostic quality. Clinical review of images by a radiologist indicated that HiRise is safe and effective when used as labeled. |
| Safety and Effectiveness | Compliance with regulations and standards | Performance: Complies with applicable FDA and international standards pertaining to electrical, mechanical, software, EMC, and radiation safety of medical devices (e.g., AAMI ES60601-1, IEC 60601-1-3, IEC 62366, IEC 62304, IEC 60601-2-44, IEC 60601-1-2, IEC 61223-3-5, NEMA PS 3.1-3.20, IEC 60825-1). |
2. Sample size used for the test set and the data provenance
The document does not specify a distinct "test set" in terms of patient cases for a statistical performance study comparing the HiRise to a ground truth or predicate quantitatively. Instead, it relies on two primary methods:
- Phantom Scans: "image quality phantoms were scanned in the HiRise and evaluated by a medical physicist." The sample size of phantoms is not specified.
- Clinical Image Review: "datasets of the humerus, elbow, forearm, hand, wrist, pelvis/hip, femur, knee, shin (lower leg or tib/fib) and foot/ankle were reviewed by a board-certified radiologist and found to be of diagnostic quality." The number of patient cases (datasets) reviewed is not specified.
The data provenance is not explicitly stated (e.g., country of origin, retrospective or prospective). However, the "clinical review of images" suggests actual patient data, likely retrospective.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Number of experts: At least one board-certified radiologist.
- Qualifications: "board-certified radiologist." Specific years of experience are not mentioned.
- Additionally, a "medical physicist" evaluated image quality phantoms.
4. Adjudication method
The adjudication method for the clinical image review is not explicitly described. It states that "a board-certified radiologist... found [images] to be of diagnostic quality." This implies a single expert's assessment without mentioning a consensus process or multiple readers.
5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done
No, a multi-reader multi-case (MRMC) comparative effectiveness study comparing human readers with AI assistance versus without AI assistance was not conducted or described. The HiRise device is a Computed Tomography X-Ray System, which directly acquires images, and the provided documentation focuses on its imaging performance versus a predicate device, not on AI-assisted interpretation.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done
Yes, an assessment of the device's standalone performance was done. The "performance testing by a medical physicist" and "clinical review of images by a radiologist" evaluating the HiRise images themselves indicate a standalone assessment of the device's output quality. There's no mention of a human-in-the-loop component being evaluated for the device's image acquisition functionality.
7. The type of ground truth used
The ground truth for evaluating the HiRise's performance was established through:
- Expert Consensus/Opinion: For clinical images, it was the "diagnostic quality" determined by a "board-certified radiologist."
- Bench Testing/Phantom Standards: For image quality phantoms, evaluation by a "medical physicist" against established image quality requirements, and verification of "optimal X-Ray tube voltage" and "increased tube current" through bench testing. Additionally, "Detector performance testing" verified image quality met requirements.
8. The sample size for the training set
The document describes the HiRise as an imaging device (hardware and associated software for image acquisition and reconstruction), not a machine learning or AI algorithm in the context of image interpretation. Therefore, there is no "training set" for an AI model mentioned in this submission. The "training set" concept is not applicable here as the device's functionality doesn't appear to be based on a trained AI for image analysis.
9. How the ground truth for the training set was established
As there is no "training set" for an AI model mentioned, this question is not applicable based on the provided text.
§ 892.1750 Computed tomography x-ray system.
(a)
Identification. A computed tomography x-ray system is a diagnostic x-ray system intended to produce cross-sectional images of the body by computer reconstruction of x-ray transmission data from the same axial plane taken at different angles. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.