Browse hierarchy: [Neurology (NE)](/submissions/NE) → [Subpart E — Neurological Surgical Devices](/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices) → [21 CFR 882.4950](/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/882.4950) → QFX — Diagnostic Neurosurgical Microscope Filter

# QFX · Diagnostic Neurosurgical Microscope Filter

_Neurology · 21 CFR 882.4950 · Class 2_

**Canonical URL:** https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX

## Overview

- **Product Code:** QFX
- **Device Name:** Diagnostic Neurosurgical Microscope Filter
- **Regulation:** [21 CFR 882.4950](/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/882.4950)
- **Device Class:** 2
- **Review Panel:** [Neurology](/submissions/NE)

## 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.

## Classification Rationale

Class II (special controls). The special controls for this device are:

## Special Controls

In combination with the general controls of the FD&C Act, the diagnostic neurosurgical microscope filter is subject to the following special controls:

- (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;
	- Spectrum of the excitation and emission filter modules when integrated in the (ii) 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 pre-operative procedures; and
	- (viii)If camera-based, spectral sensitivity of the camera.
- (2) Labeling must include:
	- Identification of the filter characteristics in conjunction with a compatible surgical (i) operating microscope, to include the following:
		- (A) Illumination spectrum and power density; and
		- (B) Excitation and emission filter spectra.
	- (ii) Instructions for calibration or pre-operative 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
	- A warning that the device is not a standalone diagnostic. (v)

*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.

## Recent Cleared Devices (5 of 5)

| Record | Device Name | Applicant | Decision Date | Decision |
| --- | --- | --- | --- | --- |
| [K251286](https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX/K251286.md) | Affirm 400 | Digital Surgery Systems, Inc. (D.B.A True Digital Surgery) | Jan 21, 2026 | SESE |
| [K240215](https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX/K240215.md) | BLUE 400; BLUE 400 S | Carl Zeiss Meditec, AG | Jun 28, 2024 | SESE |
| [K232567](https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX/K232567.md) | Myriad SPECTRA Light Source | Nico Corporation | Mar 14, 2024 | SESE |
| [K211346](https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX/K211346.md) | BLUE 400 | Carl Zeiss Meditec, AG | Jul 22, 2022 | SESE |
| [DEN180024](https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX/DEN180024.md) | Leica FL400 | Leica Microsystems (Schweiz) AG | Mar 28, 2019 | DENG |

## Top Applicants

- Carl Zeiss Meditec, AG — 2 clearances
- Digital Surgery Systems, Inc. (D.B.A True Digital Surgery) — 1 clearance
- Leica Microsystems (Schweiz) AG — 1 clearance
- Nico Corporation — 1 clearance

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**Source:** [https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX](https://fda.innolitics.com/submissions/NE/subpart-e%E2%80%94neurological-surgical-devices/QFX)

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