(445 days)
BLUE 400 is an accessory of the surgical microscope and allows the fluorescence observation of fluorophores with an excitation peak between 400 mm and the fluorescence emission observation comprising the spectrum in a spectral band of 620 - 710 nm.
The ZEISS BLUE 400 is a surgical microscope accessory used in fluorescent visualization of suspected grade III and IV gliomas during neurosurgery.
The BLUE 400 is an accessory to the Zeiss surgical microscopes (OPMI PENTERO 800, OPMI PENTERO 900, and KINEVO 900), intended to allow intraoperative viewing of malignant glioma tissue under fluorescence. The BLUE 400 accessory is entirely composed of optical filters: the "Excitation" filter and the "Emission" filters. The Excitation filter is designed to filter all light wavelengths except 400 - 470 nanometers and is optimized to pass light between 400 - 410 nanometers. The Emission filters are designed to filter all light wavelengths except 430 - 800 nanometers and is optimized to pass light between 620 - 710 nanometers.
When installed in the surgical microscopes (class I), the BLUE 400 introduces optical filters to the illumination and viewing optical paths. The BLUE 400 includes installation of a software license that facilitates use of the accessory. After the SW license is installed, the user has the option to switch from the normal white light mode of the surgical microscope to the BLUE 400 mode.
The BLUE 400 accessory, when installed in the surgical microscopes, is intended to be used in conjunction with an approved optical imaging agent that is excited mainly in the wavelength range of 400 – 410 nanometers and fluoresces in the wavelength range of 620 - 710 nanometers.
Here's a breakdown of the acceptance criteria and study information for the BLUE 400 device, based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are not explicitly stated in a quantitative manner (e.g., specific thresholds for irradiance or power). Instead, they are implied by the "Passed" result for each test, indicating that the device met the defined specifications for each performance parameter. The study is a bench performance test comparing the subject device (BLUE 400) to a predicate device (Leica FL400).
| Test | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Spectrum of the Illumination Source | Irradiance spectrum (250 nm - 1020 nm, mW/cm²) verified and assessed prior to excitation filter application. | Passed |
| Maximum Power and Irradiance of the Illumination Source | Maximum output power and irradiance measured and verified prior to excitation filter application. | Passed |
| Irradiance Spectrum of the Excitation Light and Spectral Response of the Excitation Filter | Irradiance spectrum (250 nm - 1020 nm) of illumination light after excitation filter passage measured; 50% decrease edges of blue excitation peak calculated. | Passed |
| Maximum Excitation Power and Power Density | Maximum power (mW) and power density (mW/cm²) of excitation light measured at various working distances and zoom settings and compared to the predicate device. | Passed |
| Optical Path Loss | Optical path loss calculated by dividing output signal (eyepiece without emission filter) by illumination signal (focal plane with spectrometer). | Passed |
| Spectrum of the Emission Filter | Spectrum (350 nm - 1050 nm) of the emission filter (integrated into microscope) measured; 50% edge of the spectrum calculated. | Passed |
| Homogeneity of the Excitation Light at the Focal Point | Intensity profile of reflected signal from white paper imaged by camera demonstrated homogeneity. | Passed |
| System Sensitivity | Fluorescence signal in the eyepiece of the subject device compared to the predicate device using a fluorescent target. | Passed |
| Pre-Operative Phantom Test | Suitability of the ZEISS BLUE 400 test phantom for pre-operative checks of KINEVO 900 and OPMI PENTERO 900 demonstrated via camera imaging and eyepiece observation. | Passed |
| Spectrum of Camera Filter | Spectrum at camera interface measured to demonstrate camera filter blocks near infrared and infrared leakage of excitation light. | Passed |
2. Sample Size Used for the Test Set and Data Provenance
The document describes bench performance testing. Therefore, the "test set" in the traditional sense of patient data is not applicable. The testing involves:
- Test Sets: The devices themselves (subject device BLUE 400 and predicate device Leica FL400) and various optical components (filters, light sources, specialized targets/phantoms).
- Data Provenance: The tests were conducted internally by Carl Zeiss Meditec AG, as part of their 510(k) submission. This is a prospective bench study. No external data sources or patient data are mentioned.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
Not applicable. This was a bench performance study assessing physical and optical properties, not a clinical study requiring expert interpretation of patient data to establish ground truth. The "ground truth" was established by the physical measurements and calculations against defined specifications.
4. Adjudication Method for the Test Set
Not applicable. This was a direct measurement and comparison bench study, not a clinical study requiring adjudication of expert readings.
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
Not applicable. This device is an accessory (an optical filter) to a surgical microscope, not an AI or imaging diagnostic tool that would typically involve a multi-reader multi-case study for diagnostic accuracy or human performance improvement.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
The device itself is an optical filter system for a surgical microscope. It does not have an "algorithm" in the sense of an AI or software that performs standalone interpretation. Its function is to modify light for improved visualization by a human surgeon. Therefore, standalone algorithm performance is not applicable. The document does mention Software verification testing was performed in accordance with FDA Guidance to demonstrate the software (for the license installation and mode switching) is performing as intended. This is analogous to a standalone performance check for the software component, but not for an interpretative algorithm.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
For the bench performance tests, the "ground truth" was established by:
- Physical measurements: Using calibrated instruments like spectrometers, power meters, and thermopiles to measure optical properties (irradiance spectrum, power, density, emission spectrum).
- Calculations: Such as calculating the 50% decrease edges of spectral peaks and optical path loss.
- Comparison to predefined specifications: The results were evaluated against specific technical requirements and specifications for each test.
- Comparison to a predicate device: For certain tests like maximum excitation power density and system sensitivity, the performance of the subject device was compared directly to the predicate device (Leica FL400).
8. The Sample Size for the Training Set
Not applicable. This is not a machine learning or AI-based device that requires a "training set."
9. How the Ground Truth for the Training Set Was Established
Not applicable. As above, there is no training set for this device.
§ 882.4950 Diagnostic neurosurgical microscope filter.
(a)
Identification. A diagnostic neurosurgical microscope filter is a device intended for use during neurosurgery to visualize fluorescence and enhance visualization of tissue associated with a specific disease or condition.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use, and verify and validate filter specifications and functional characteristics, including the following:
(i) Spectrum and intensity of the illumination source;
(ii) Spectrum of the excitation and emission filter modules when integrated in the surgical operating microscope;
(iii) Excitation power and power density;
(iv) Optical path loss from illumination source to objective lens or microscope camera;
(v) Homogeneity of the excitation light at the focal plane;
(vi) Fluorescence detection sensitivity;
(vii) Verification of calibration or preoperative procedures; and
(viii) If camera-based, spectral sensitivity of the camera.
(2) Labeling must include:
(i) Identification of the filter characteristics in conjunction with a compatible surgical operating microscope, to include the following:
(A) Illumination spectrum and power density; and
(B) Excitation and emission filter spectra.
(ii) Instructions for calibration or preoperative checks to ensure device functionality prior to each use;
(iii) Instructions for use with compatible surgical operating microscopes, external light sources, and cameras;
(iv) A warning that the device should only be used with fluorophores approved for use within the specified spectral ranges; and
(v) A warning that the device is not a standalone diagnostic.