(270 days)
The Affirm 800 is used in viewing intra-operative blood flow in the cerebral vascular area including, but not limited to, assessing cerebral vessel branch occlusion, as well as intraoperative blood flow and vessel patency in bypass surgical procedures in neurosurgery.
The Affirm 800 module is designed to work in conjunction with the Class I Digital Surgical Microscope (DSM) RE3. The Affirm 800 module, a Class II device, comprises hardware and software components that enable the Digital Surgical Microscope to emit excitation light in specific wavelengths to activate the fluorescence properties of Indocyanine Green (ICG). The fluorescence signal emitted by the patient represents the distribution of the infrared dye in the patient's blood vessels during surgery. The emitted light is then captured by the optics of the digital microscope, passed through filters to remove unwanted wavelengths of light, and finally detected by the image sensors. This detected signal is then projected on a 3D monitor, which is part of the microscope system, enabling the surgeon to view the magnified image.
The integrated Affirm 800 fluorescence module is used to visualize infrared fluorescent areas in the surgical field and includes features to record and play back a video clip of the area of focus where fluorescent light is emitted. The module has been designed for excitation in the wavelength range from 740 nm to 800 nm and for fluorescence visualization in the wavelength range from 820 nm to 900 nm. The fluorescence feature generates an image in the infrared spectrum, which means it cannot be seen by the naked eye.
Here's a breakdown of the acceptance criteria and the study details for the Affirm 800 device, based on the provided FDA 510(k) Clearance Letter:
Note: The provided document is an FDA 510(k) Clearance Letter and a 510(k) Summary. These documents summarize the manufacturer's performance testing and justification for substantial equivalence. They don't typically include granular details about every aspect of the study design (like specific expert qualifications, adjudication methods, or sample sizes for specific training sets) that might be found in a full study report or a more comprehensive submission. Therefore, some information requested may not be explicitly available in this type of document and will be noted as "Not explicitly stated."
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Metric (as implied by test methods) | Acceptance Criteria (implied) | Reported Device Performance |
|---|---|---|---|
| Image Quality (NIR Fluorescence) | Sensitivity to ICG Molar Concentration: | Equivalent to predicate | Pass (for: Weber contrast, SNR, Fluorescence Pixel Intensity, LOD, LOQ, Signal linearity) |
| - Weber contrast | (implied by "confirm equivalent performance") | ||
| - Signal to Noise Ratio (SNR) | |||
| - Fluorescence Pixel Intensity | |||
| - Limit of detection (LOD) | |||
| - Limit of quantification (LOQ) | |||
| - Signal linearity (up to 3.2 micromolar) | |||
| Spatial & Temporal Noise | Spatial noise | Within acceptable limits | Pass |
| Temporal noise | |||
| Stereoscopic Display | Left and Right Eye Comparison | Consistent performance | Pass |
| Stereoscopic Crosstalk: | Within acceptable limits | Pass (for: Stereoscopic Extinction Ratio, Stereoscopic Crosstalk) | |
| - Stereoscopic Extinction Ratio | |||
| - Stereoscopic Crosstalk | |||
| ICG Depth Penetration | Sensitivity to NIR fluorescence depth penetration: | Equivalent to predicate | Pass (for: Weber Contrast, SNR) |
| - Weber Contrast | (implied by "confirm equivalent performance") | ||
| - Signal-to-Noise Ratio | |||
| Clinical Image Quality | Surgeons' image quality evaluation (scale 1-5) | Satisfactory clinical image quality | Pass (image quality evaluated in 5 porcine models) |
| Software Functionality | Software Verification & Validation (V&V) | Compliance with FDA guidance | Pass |
Study Details
-
Sample Size used for the test set and the data provenance:
- Sample Size (Clinical/Animal Study): 5 porcine models.
- Data Provenance: Not explicitly stated, but likely conducted by the manufacturer or a contracted research organization in a controlled setting, given it's an animal study. It is a prospective study by nature of being a "conducted" animal study.
-
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Number of Experts: Not explicitly stated. The document mentions "Surgeons evaluated image quality." The exact number of surgeons is not provided.
- Qualifications of Experts: Only "Surgeons" are mentioned. No specific experience levels (e.g., "radiologist with 10 years of experience") are provided.
-
Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Adjudication Method: Not explicitly stated. The document only says "Surgeons evaluated image quality." It doesn't specify if this was an individual assessment, a consensus, or involved an adjudication process for discrepancies.
-
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:
- MRMC Study: No, a multi-reader multi-case comparative effectiveness study was not explicitly mentioned or described. The performance testing focused on device characteristics and an animal study for image quality evaluation, not on human reader performance with or without AI assistance. The Affirm 800 as described is an imaging module, not an AI-assisted diagnostic tool.
-
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Standalone Performance: Not applicable in the context of an "algorithm only" device. The Affirm 800 is an imaging system designed for intra-operative visualization with a human surgeon-in-the-loop. Its performance is evaluated on its ability to acquire and display clear fluorescent images, not on an algorithm making a diagnostic decision by itself. However, the technical aspects of image quality (e.g., sensitivity, SNR, depth penetration) could be considered standalone measurements of the imaging capability.
-
The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Ground Truth: For the animal study, the "ground truth" for image quality was based on the subjective evaluation by surgeons on a defined scale (1 to 5). For the technical image quality tests, the "acceptance criteria" likely served as the ground truth, comparing measured values (e.g., Weber contrast, SNR) against pre-defined thresholds or performance of the predicate device. There is no mention of pathology or outcomes data as ground truth for this device's performance.
-
The sample size for the training set:
- Training Set Sample Size: Not explicitly stated. The document describes verification and validation testing, but it does not detail a separate "training set" for a machine learning model, as the device is specified as an angiographic X-ray system module, not an AI algorithm for diagnosis.
-
How the ground truth for the training set was established:
- Ground Truth for Training Set: Not explicitly stated or applicable, as a discrete "training set" for an AI model (with associated ground truth) is not described in the context of this device's submission summary. The device's validation focuses on engineering specifications and direct performance measures rather than training an AI.
§ 892.1600 Angiographic x-ray system.
(a)
Identification. An angiographic x-ray system is a device intended for radiologic visualization of the heart, blood vessels, or lymphatic system during or after injection of a contrast medium. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.