(229 days)
The Xpress BCD is a reusable device indicated for use with stereotactic biopsy platforms to apply temporary focal mechanical compression to a stereotactic breast biopsy site to achieve hemostasis. Rx Only. Federal (USA) law restricts this device to sale by or on the order of a physician.
The XPress BCD device is an accessory used in conjunction stereotactic breast biopsy devices. The XPress BCD is comprised of Delrin® DuPont (acetal homopolymer resin, Delrin 150NC010), or similar material. There are three (3) independent XPress BCD device configurations that are provided as a set: configuration 1 (large flat), configuration 2 (modified pyramidal), and configuration 3 (modified spherical). These different configurations are used based on the biopsy site being treated. The Xpress design includes a mechanical slot for attaching to compression paddles of mammographic x-ray systems. The XPress BCD is used in conjunction with the XPress BCD Cover (K863853; classification JAA; manufactured by Preferred Medical Products, Ducktown, TN). It is used to enclose the XPress BCD for use as intended. The XPress BCD Cover, is a sterile, single-use covering. The XPress BCD Cover is a 4 X 5 inches covering of a 0.002 mm thick polyethylene blend material, and its closure system is a round or oblong synthetic rubber band made of a polyisoprene polymer, measuring 2 X 1/8 X 1/16 inches. The XPress BCD Cover is packaged with the XPress BCD or may be purchased separately.
1. Acceptance Criteria and Reported Device Performance
The document describes a clinical study to evaluate the performance of the XPress BCD Breast Compression Device for achieving hemostasis after stereotactic-guided breast biopsy. The primary clinical performance measure/adverse effect was hematoma formation, defined as a new three-dimensional mass (> 0.52 cm³) detected on standard post-biopsy full-field mammography.
The document does not explicitly state pre-defined acceptance criteria with specific numerical thresholds for hematoma formation rate. However, the study results are presented, demonstrating the device's performance in this aspect.
Table of Acceptance Criteria (Implied) and Reported Device Performance:
| Performance Measure (Implied Acceptance Criterion) | Reported Device Performance (XPress BCD) |
|---|---|
| Rate of Immediate Post-Compression Hematoma | 7.5% (9/120 biopsies) by primary investigators |
| Rate of Delayed Hematoma (up to one week) | 3.3% (4/120 biopsies) |
| Rate of Fat Necrosis | 0% (0/65 evaluable sites at one year post-biopsy) |
| Rate of Hematoma (Independent Reviewer A) | 5.8% (7/120 biopsies) |
| Rate of Hematoma (Independent Reviewer B) | 7.5% (9/120 biopsies) |
| Rate of Fat Necrosis (Independent Reviewers) | 0% (0/65 evaluable sites) |
Note: The document focuses on demonstrating that the device is "as safe and effective as the predicate device" through a clinical study, rather than specific acceptance thresholds.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: The study included 120 biopsies performed on 118 female subjects.
- Data Provenance: The study was a "prospective historical control single arm clinical study (NCT02327598)" conducted at "one investigational site". The country of origin is not explicitly stated, but the FDA submission suggests it is likely the USA. The study design is prospective.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
- Number of Experts: The study involved primary investigators and two "independent mammographers" for review.
- Five investigators and six assistants participated in the study for immediate post-compression hematoma detection.
- Two independent mammographers reviewed the imaging for hematoma and fat necrosis.
- Qualifications of Experts: The qualifications of the "primary investigators" are not specified beyond their role in the study. The "independent mammographers" are referred to as such, suggesting they are qualified radiologists specializing in mammography, but their specific years of experience or board certifications are not provided.
4. Adjudication Method for the Test Set
- The document implies that immediate post-compression hematoma detection was performed by primary investigators.
- For delayed hematomas and fat necrosis, the "primary study" and "independent mammographers" assessed the mammographic evidence.
- There is no explicit mention of an adjudication method (like 2+1 or 3+1 consensus) if there were disagreements between the independent mammographers or between the primary study findings and the independent reviewers. Both reviewers' findings for hematoma and fat necrosis are reported separately, suggesting independent assessments without a formal reconciliation process mentioned.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done
No, an MRMC comparative effectiveness study was not explicitly stated or described. The study was a "single arm clinical study" focusing on the XPress BCD device's performance after biopsy. There is no comparison of human readers with vs. without AI assistance. The study evaluates a physical device, not an AI algorithm.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
This question is not applicable. The XPress BCD is a physical breast compression device, not an AI algorithm. Therefore, no standalone algorithm performance study would be conducted.
7. The type of ground truth used
The ground truth for hematoma formation was based on:
- Clinical observation: Primary investigators detected immediate post-compression hematoma.
- Imaging review: Mammograms were used to detect hematomas and fat necrosis, reviewed by primary study staff and two independent mammographers.
- Patient follow-up/outcomes data: Phone contact after 24 hours and 7 days, and clinical/ultrasound evaluation for returning patients, were part of the follow-up for adverse events. Hematoma was defined as a "new three dimensional mass (> 0.52 cm') detected on standard post-biopsy full-field mammography." This suggests an imaging-based "ground truth" for the primary outcome.
8. The Sample Size for the Training Set
This question is not applicable. The XPress BCD is a physical device, not a machine learning algorithm. Therefore, there is no "training set" in the context of AI.
9. How the Ground Truth for the Training Set was Established
This question is not applicable as there is no training set for a physical device.
§ 892.1710 Mammographic x-ray system.
(a)
Identification. A mammographic x-ray system is a device intended to be used to produce radiographs of the breast. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.