NCT07546617

Brief Summary

This research is being done to better characterize the part of the nose that helps us smell. Currently, the only ways to study smell loss mostly rely on how people report it, rather than being able to see the underlying structures directly. In this study, we will use a special microscope (Confocal Laser Endomicroscopy (CLE)), originally developed for brain tissue, to look at the part of the nose that helps to detects smell. We hope to identify the tiny structures in that area and see how they might be different in people who have smell loss compared to those who do not.

Trial Health

63
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Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
36

participants targeted

Target at P25-P50 for all trials

Timeline
13mo left

Started Jul 2026

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

April 16, 2026

Completed
7 days until next milestone

First Posted

Study publicly available on registry

April 23, 2026

Completed
2 months until next milestone

Study Start

First participant enrolled

July 1, 2026

Expected
10 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 30, 2027

3 months until next milestone

Study Completion

Last participant's last visit for all outcomes

July 31, 2027

Last Updated

April 23, 2026

Status Verified

April 1, 2026

Enrollment Period

10 months

First QC Date

April 16, 2026

Last Update Submit

April 16, 2026

Conditions

Keywords

Confocal Laser EndomicroscopyEndoscopic Sinus SurgerySmell LossEndonasal Skull Base SurgeryOlfactory Dysfunction

Outcome Measures

Primary Outcomes (1)

  • Evaluate the feasibility of in vivo CLE imaging of the olfactory cleft and nasal turbinate and determine whether CLE features correlate with validated psychophysical olfactory testing and patient-reported quality-of-life measures.

    (1) High feasibility (≥85% interpretable images); (2) identifiable CLE signatures associated with OD severity; (3) significant correlations between CLE features, TDI scores, and symptom burden.

    On day of Surgery, Day 0

Secondary Outcomes (1)

  • Compare in vivo CLE imaging features with histopathologic findings from superior turbinate tissue, when available, to identify candidate in vivo imaging biomarkers.

    On day of Surgery, Day 0

Study Arms (2)

Target Group (Patients with Olfactory Complaints)

Patients who have olfactory complaints and are undergoing endoscopic sinus or endonasal skull base surgery while under general anesthesia where the nasal turbinate is accessible, per their standard of care.

Device: CONVIVO systemOther: Conventional histologic evaluationDrug: Fluorescein injection, USP 10%

Control Group

Controls will consist of surgical patients without subjective olfactory complaints and with expected normal psychophysical testing. Patients who are already undergoing endoscopic sinus or endonasal skull base surgery while under general anesthesia where the nasal turbinate is accessible, per their standard of care.

Device: CONVIVO systemOther: Conventional histologic evaluationDrug: Fluorescein injection, USP 10%

Interventions

Approximately 2-5 minutes following administration of FNa in situ imaging will be performed by the participating surgeon ensuring proper technique. Prior to entering the surgical field, the probe will be covered in a disposable sterile sheath that is manufactured with quality assurance for this purpose. The probe will gently be held against the tissue interface while imaging occurs. Following image acquisition, a pathologist present in the operating room, will review and capture each image.

Control GroupTarget Group (Patients with Olfactory Complaints)

Following image acquisition, if clinically indicated, the tissue region imaged with the CONVIVO system will then be biopsied. This will be passed immediately off the surgical field as a research specimen and provided to a member of the research team to be prepared for conventional histologic evaluation. The specimen will be labeled with the deidentified subject and sample number. This sequence will then be repeated for each successive sample.

Control GroupTarget Group (Patients with Olfactory Complaints)

Sodium fluorescein will be administered intravenously or topically (applied directly to nasal mucosa) at doses of 5-10 mg/kg (not exceeding 20 mg/kg cumulative). Administration will be performed by the anesthesia team in the operating room.

Also known as: AK-FLUOR, FNa
Control GroupTarget Group (Patients with Olfactory Complaints)

Eligibility Criteria

Age18 Years+
Sexall
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

Adults undergoing endoscopic sinus or endonasal skull base surgery while under general anesthesia where the nasal turbinate is accessible at Dartmouth Hitchcock Medical Center.

You may qualify if:

  • Adults aged ≥18 years
  • Undergoing endoscopic sinus or endonasal skull base surgery while under - general anesthesia where the nasal turbinate is accessible
  • Able to complete study questionnaires and psychophysical smell testing
  • Able to provide informed consent.

You may not qualify if:

  • Known allergy or hypersensitivity to fluorescein
  • Pregnancy
  • Medical instability precluding participation
  • Severe anatomic obstruction preventing safe access to the olfactory cleft and nasal turbinate
  • Any other safety concern identified by the investigator

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Dartmouth-Hitchcock Medical Center

Lebanon, New Hampshire, 03755, United States

Location

MeSH Terms

Conditions

Anosmia

Interventions

FluoresceinFluoresceins

Condition Hierarchy (Ancestors)

Olfaction DisordersSensation DisordersNeurologic ManifestationsNervous System DiseasesSigns and SymptomsPathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Spiro CompoundsHydrocarbons, CyclicHydrocarbonsOrganic ChemicalsXanthenesHeterocyclic Compounds, 3-RingHeterocyclic Compounds, Fused-RingHeterocyclic CompoundsPolycyclic Compounds

Central Study Contacts

Study Design

Study Type
observational
Observational Model
CASE CONTROL
Time Perspective
CROSS SECTIONAL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Director of the Sinus Research Center Assistant Professor of Surgery, Geisel School of Medicine, Dartmouth

Study Record Dates

First Submitted

April 16, 2026

First Posted

April 23, 2026

Study Start (Estimated)

July 1, 2026

Primary Completion (Estimated)

April 30, 2027

Study Completion (Estimated)

July 31, 2027

Last Updated

April 23, 2026

Record last verified: 2026-04

Data Sharing

IPD Sharing
Will not share

Locations