---
kind: "section"
citation: "21 C.F.R. § 882.4950"
title: "21"
number: "882.4950"
heading: "Diagnostic neurosurgical microscope filter."
url: "https://uscodex.org/cfr/21/882.4950"
---

# §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.**

## Notes

### Amendments

[86 FR 73973, Dec. 29, 2021]

### Authority

Authority: 21 U.S.C. 351, 360, 360c, 360e, 360j, 360 l, 371.

### Source

Source: 44 FR 51730, Sept. 4, 1979, unless otherwise noted.

### Amendments

[86 FR 73973, Dec. 29, 2021]