Suspected Grade III and IV Gliomas Requiring Surgical InterventionIMED-GLOW400NCT07366892
Leica Microsystems Sponsored PMCF Study to Collect and Confirm Clinical Data on the Performance of the GLOW400 Device When Used in Accordance With Its Intended Use
An observational study of Suspected Grade III and IV Gliomas Requiring Surgical Intervention and Neurosurgical Procedure, run by Leica Microsystems (Schweiz) AG at 2 sites in 2 countries.
Trial summary
This post-market clinical follow-up (PMCF) study aims to confirm the safety and performance of the GLOW400 surgical microscope accessory when used in conjunction with the ARveo8x surgical microscope. The study evaluates fluorescence visualization and image quality during standard surgical procedures in neurosurgery. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Suspected Grade III and IV Gliomas Requiring Surgical Intervention, Neurosurgical Procedure, Glioma
- What is being tested?
- GLOW400 is a digital surgical microscope accessory used in fluorescent visualization of suspected grade III or IV gliomas during neurosurgery.
- Type of treatment
- Injection or infusion, Medical device
- How many people
- 37 participants
- Where
- 2 sitesin 2 countries
- Study dates
- 28 Apr 2026to 31 Aug 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patient population will include patients with suspected grade III or IV gliomas requiring surgical intervention, and who meet the Inclusion/Exclusion Criteria for the IMED-GLOW400 Study.
Who may be able to join
- Participants must be 18 years of age or older at the time of signing the informed consent.
- Participants must have suspected high-grade glioma (WHO grade III-IV) as evidenced by preoperative imaging modalities, which require surgical intervention.
- The active substance 5-aminolevulinic acid (5-ALA) fluorescence dye is administered according to the 5-ALA instructions for use.
- The participant or their legal representative must understand the study and have voluntarily signed and dated the Informed Consent Form, which has been approved by the Sponsor and the Ethics Committee for this study.
- Note for Switzerland only:
- Enrollment via legal representative is not permitted. Therefore, only patients who are capable of providing informed consent themselves will be eligible for inclusion in Switzerland.
Who cannot join
- Known allergy to 5-ALA hydrochloride or protoporphyrin.
- Patients with porphyria (a condition characterized by the inability to break down protoporphyrin).
- Any uncontrolled systemic condition that may adversely affect the surgical outcome.
- Patients holding United States citizenship.
Trial locations and contacts
2 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
Leica Microsystems Clinical Affairs Department contact
2 sites in 2 countries
Portugal1 site, 1 recruiting
- Recruiting
Unidade Local de Saúde de São João
Porto
Pedro Alberto Silva, MD PhD FEBNS, +351 933 205 202, pa.silva@ulssjoao.min-saude.pt
Switzerland1 site, 1 recruiting
- Recruiting
University Hospital Basel
Basel
Raphael Guzman, Prof. med., +41 61 265 33 68, raphael.guzman@usb.ch
About this study
Official title: Fluorescence Visualization and Image Quality Evaluation of Digital Visualization of Suspected Grade III and/or IV Gliomas During Neurosurgery (Leica GLOW400)
This post-market clinical follow-up (PMCF) study aims to confirm the safety and performance of the GLOW400 surgical microscope accessory when used in conjunction with the ARveo8x surgical microscope. The study evaluates fluorescence visualization and image quality during standard surgical procedures in neurosurgery. It is a non-interventional, observational study conducted in routine care settings across multiple European sites.
Read the detailed description
The IMED-GLOW400 study is a prospective, observational, non-interventional clinical investigation conducted in the European Economic Area and Switzerland. It involves the use of the GLOW400 accessory, which digitally enhances fluorescence signals during neurosurgery, providing improved anatomical visualization and contrast. The study compares GLOW400 with the benchmark FL400 optical filter system.
The primary objective is to confirm the image quality and fluorescence visualization performance of GLOW400. Secondary objectives include validating product claims and assessing user experience and safety. An exploratory objective evaluates the extent of tumor resection using volumetric analysis of pre- and post-operative MRI scans.
Data will be collected through structured questionnaires, histopathology confirmation, optional resection forms, and intraoperative video recordings. The study will enroll 37 patients, with at least 29 complete datasets required for analysis. The duration of the study is estimated at 5 to 6 months, with each patient participating only during the surgical procedure.
The study complies with ISO 14155:2020, GDPR, and the Declaration of Helsinki. Ethics Committee approval and informed consent are mandatory prior to enrollment. No additional procedures beyond standard of care are introduced, and risks are limited to those associated with routine surgical practice.
- Conditions
- Suspected Grade III and IV Gliomas Requiring Surgical Intervention, Neurosurgical Procedure, Glioma, Glioblastoma (GBM)
- Being tested
- GLOW400 is a digital surgical microscope accessory used in fluorescent visualization of suspected grade III or IV gliomas during neurosurgery.
- Keywords
- GLOW400, ARveo8x, Digital surgical microscope, 5-ALA fluorescence, Image quality assessment, Grade III gliomas, Grade IV gliomas, High-grade glioma, fluorescence-guided surgery
- Medical subject headings
- Glioma, Glioblastoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
GLOW400 is a digital surgical microscope accessory used in fluorescent visualization of suspected grade III or IV gliomas during neurosurgery.Device
The digital surgical microscope accessory GLOW400 is using the optical excitation and emission filtering of the FL400. The FL400 provides an illumination filter (380nm - 430nm) which when engaged into the light source path of the surgical operating microscope provides, via a light guide, a fluorescence excitation light system used in conjunction with an approved tumor-selective substance (fluorophore) (e.g. Protoporphyrin IX (PpIX) which is resulting of the metabolization of 5-ALA (5 - aminolaevulinic acid)) for tissue characterization in the open neurosurgery field. PpIX is strongly fluorescent with a peak at λ=635 nm as red-violet after excitation with blue light (λ=380-410 nm). The digital surgical microscope accessory GLOW400 is using the optical excitation and emission filtering of the FL400. The fluorescence signal visualized depicts the distribution of the dye in the patient's tissues during the surgical procedure.
| Study group | Role | What they receive |
|---|---|---|
| GLOW400 | Not described Receives: Device: GLOW400 is a digital surgical microscope accessory used in fluorescent visualization of suspected grade III or IV gliomas during neurosurgery. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Flourescence visibility
Performance will be evaluated using Questionnaire, a structured Likert-scale survey completed by the operating surgeon during and after surgery.
The questionnaire assesses:
- perceived intensity of fluorescence
- perceived volume/ shape and relative location
- perceived distribution of fluorescence
- anatomical and fluorescence observation (GLOW400 Anatomy only)
Each item is rated on a 5-point Likert scale:
- = Not available
- = Insufficient
- = Sufficient
- = Very good
- = Excellent
Higher scores indicate better performance.
The outcome is considered acceptable if all ratings are ≥3 (Sufficient or better).
Measured: Periprocedural
Image quality
Performance will be evaluated using Questionnaire, a structured Likert-scale survey completed by the operating surgeon during and after surgery. The questionnaire assesses::
- Stereoscopic Perception (3D Depth perception)
- Resolution
- Noise
- Latency
Each item is rated on a 5-point Likert scale:
- = Not available
- = Insufficient
- = Sufficient
- = Very good
- = Excellent
Higher scores indicate better performance.
The outcome is considered acceptable if all ratings are ≥3 (Sufficient or better).
Measured: Periprocedural
Anatomy of the brain, including Vessels (GLOW400 Anatomy only)
Performance will be evaluated using Questionnaire, a structured Likert-scale survey completed by the operating surgeon during and after surgery. The questionnaire assesses:
- Neuroanatomy structures
- Vascular structures 4. Perceived contrast (GLOW400 HiFluo only) 5. Bleeding visibility (GLOW400 Anatomy only) 6. Traces of remaining fluorescence (GLOW400 HiFluo only)
Each item is rated on a 5-point Likert scale:
- = Not available
- = Insufficient
- = Sufficient
- = Very good
- = Excellent
Higher scores indicate better performance.
The outcome is considered acceptable if all ratings are ≥3 (Sufficient or better).
Measured: Periprocedural
Secondary outcomes (1)
The secondary objectives of this Post-Market Clinical Follow-up (PMCF) study are to assess the continued safety of the device.
Safety will be evaluated using Questionnaire B, completed postoperatively by the surgical team. It captures:
- Dizziness through using digital 3D visualization
- Delayed, interrupted or hindered surgery due to different causes
- Occurred injuries to the patient
- Breach of sterility
- Any patient or user tissue burn event reported.
- Confirm user experience with the use of the device in real clinical practice, supporting the marketing claims:
- Confidence in decision
- Focus during procedure
- Surgical course of action
- User experience
- Mental fatigue
Responses are binary:
- = Yes (event occurred)
- = No (event did not occur)
Lower scores (2 = No) indicate better safety outcomes.
The outcome is acceptable if no safety events are reported.
Measured: Postoperatively
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted26 Jan 2026
- Study start28 Apr 2026
- Primary completion28 Feb 2027 (estimated)
- Study completion31 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Suspected Grade III and IV Gliomas Requiring Surgical InterventionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 37 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Leica Microsystems (Schweiz) AG
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07366892
- Sponsor's protocol ID
- GLOW400-PMCFSTUDYPLAN-202501
- Acronym
- IMED-GLOW400
- Status last verified
- Oct 2026
- First submitted
- 7 Jan 2026
- Last updated
- 3 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: IPD used in the results publication.
Study at a glance
From the registry record, last updated by the sponsor on 3 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Fluorescence Visualization and Image Quality Evaluation of Digital Visualization of Suspected Grade III and/or IV Gliomas During Neurosurgery (Leica GLOW400)
- ClinicalTrials.gov ID
- NCT07366892
- Acronym / sponsor ID
- IMED-GLOW400 / GLOW400-PMCFSTUDYPLAN-202501
- Conditions
- Suspected Grade III and IV Gliomas Requiring Surgical Intervention, Neurosurgical Procedure, Glioma, Glioblastoma (GBM)
- Keywords
- GLOW400, ARveo8x, Digital surgical microscope, 5-ALA fluorescence, Image quality assessment, Grade III gliomas, Grade IV gliomas, High-grade glioma
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 37 participants (estimated)
- Lead sponsor
- Leica Microsystems (Schweiz) AGIndustry (pharma, biotech, devices)
- Study start
- 28 Apr 2026 (actual)
- Primary completion
- 28 Feb 2027 (estimated)
- Study completion
- 31 Aug 2027 (estimated)
- First posted
- 26 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This post-market clinical follow-up (PMCF) study aims to confirm the safety and performance of the GLOW400 surgical microscope accessory when used in conjunction with the ARveo8x surgical microscope. The study evaluates fluorescence visualization and image quality during standard surgical procedures in neurosurgery. It is a non-interventional, observational study conducted in routine care settings across multiple European sites.
Detailed description
The IMED-GLOW400 study is a prospective, observational, non-interventional clinical investigation conducted in the European Economic Area and Switzerland. It involves the use of the GLOW400 accessory, which digitally enhances fluorescence signals during neurosurgery, providing improved anatomical visualization and contrast. The study compares GLOW400 with the benchmark FL400 optical filter system.
The primary objective is to confirm the image quality and fluorescence visualization performance of GLOW400. Secondary objectives include validating product claims and assessing user experience and safety. An exploratory objective evaluates the extent of tumor resection using volumetric analysis of pre- and post-operative MRI scans.
Data will be collected through structured questionnaires, histopathology confirmation, optional resection forms, and intraoperative video recordings. The study will enroll 37 patients, with at least 29 complete datasets required for analysis. The duration of the study is estimated at 5 to 6 months, with each patient participating only during the surgical procedure.
The study complies with ISO 14155:2020, GDPR, and the Declaration of Helsinki. Ethics Committee approval and informed consent are mandatory prior to enrollment. No additional procedures beyond standard of care are introduced, and risks are limited to those associated with routine surgical practice.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| GLOW400 | – | Device: GLOW400 is a digital surgical microscope accessory used in fluorescent visualization of suspected grade III or IV gliomas during neurosurgery. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patient population will include patients with suspected grade III or IV gliomas requiring surgical intervention, and who meet the Inclusion/Exclusion Criteria for the IMED-GLOW400 Study.
Key inclusion criteria (6 listed)
- Participants must be 18 years of age or older at the time of signing the informed consent.
- Participants must have suspected high-grade glioma (WHO grade III-IV) as evidenced by preoperative imaging modalities, which require surgical intervention.
- The active substance 5-aminolevulinic acid (5-ALA) fluorescence dye is administered according to the 5-ALA instructions for use.
- The participant or their legal representative must understand the study and have voluntarily signed and dated the Informed Consent Form, which has been approved by the Sponsor and the Ethics Committee for this study.
- Enrollment via legal representative is not permitted. Therefore, only patients who are capable of providing informed consent themselves will be eligible for inclusion in Switzerland.
Key exclusion criteria (4 listed)
- Known allergy to 5-ALA hydrochloride or protoporphyrin.
- Patients with porphyria (a condition characterized by the inability to break down protoporphyrin).
- Any uncontrolled systemic condition that may adversely affect the surgical outcome.
- Patients holding United States citizenship.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| GLOW400 is a digital surgical microscope accessory used in fluorescent visualization of suspected grade III or IV gliomas during neurosurgery.The digital surgical microscope accessory GLOW400 is using the optical excitation and emission filtering of the FL400. The FL400 provides an illumination filter (380nm - 430nm) which when engaged into the light source path of the surgical operating microscope provides, via a light guide, a fluorescence excitation light system used in conjunction with an approved tumor-selective substance (fluorophore) (e.g. Protoporphyrin IX (PpIX) which is resulting of the metabolization of 5-ALA (5 - aminolaevulinic acid)) for tissue characterization in the open neurosurgery field. PpIX is strongly fluorescent with a peak at λ=635 nm as red-violet after excitation with blue light (λ=380-410 nm). The digital surgical microscope accessory GLOW400 is using the optical excitation and emission filtering of the FL400. The fluorescence signal visualized depicts the distribution of the dye in the patient's tissues during the surgical procedure. | Device | GLOW400 |
Primary outcome
Flourescence visibility
Time frame: Periprocedural
Performance will be evaluated using Questionnaire, a structured Likert-scale survey completed by the operating surgeon during and after surgery. The questionnaire assesses: 1. perceived intensity of fluorescence 2. perceived volume/ shape and relative location 3. perceived distribution of fluorescence 4. anatomical and fluorescence observation (GLOW400 Anatomy only) Each item is rated on a 5-point Likert scale: 1. = Not available 2. = Insufficient 3. = Sufficient 4. = Very good 5. = Excellent Higher scores indicate better performance. The outcome is considered acceptable if all ratings are ≥3 (Sufficient or better).
Image quality
Time frame: Periprocedural
Performance will be evaluated using Questionnaire, a structured Likert-scale survey completed by the operating surgeon during and after surgery. The questionnaire assesses:: 1. Stereoscopic Perception (3D Depth perception) 2. Resolution 3. Noise 4. Latency Each item is rated on a 5-point Likert scale: 1. = Not available 2. = Insufficient 3. = Sufficient 4. = Very good 5. = Excellent Higher scores indicate better performance. The outcome is considered acceptable if all ratings are ≥3 (Sufficient or better).
Anatomy of the brain, including Vessels (GLOW400 Anatomy only)
Time frame: Periprocedural
Performance will be evaluated using Questionnaire, a structured Likert-scale survey completed by the operating surgeon during and after surgery. The questionnaire assesses: 1. Neuroanatomy structures 2. Vascular structures 4. Perceived contrast (GLOW400 HiFluo only) 5. Bleeding visibility (GLOW400 Anatomy only) 6. Traces of remaining fluorescence (GLOW400 HiFluo only) Each item is rated on a 5-point Likert scale: 1. = Not available 2. = Insufficient 3. = Sufficient 4. = Very good 5. = Excellent Higher scores indicate better performance. The outcome is considered acceptable if all ratings are ≥3 (Sufficient or better).
1 secondary outcome
The secondary objectives of this Post-Market Clinical Follow-up (PMCF) study are to assess the continued safety of the device.
Time frame: Postoperatively
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Nov 2026.
- Individual participant dataSharing planned: Yes. IPD used in the results publication.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Leica Microsystems Clinical Affairs Department contact
2 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Suspected Grade III and IV Gliomas Requiring Surgical Intervention and Neurosurgical Procedure, run by Leica Microsystems (Schweiz) AG at 2 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 3 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Portugal, Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Leica Microsystems Clinical Affairs Department (+41 796428004, clinical.affairs@leica-microsystems.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Flourescence visibility (time frame: Periprocedural). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Nov 2026.