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Prospective Study to Validate the Imaging Biomarker for NCP (R33)

Prospective Study to Validate the Imaging Biomarker for Neuropathic Corneal Pain.

Status
Suspended
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT05653921
Enrollment
438
Registered
2022-12-16
Start date
2022-12-16
Completion date
2026-10-31
Last updated
2026-01-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Dry Eye Syndromes, Corneal Disease

Brief summary

The aim of this study is establish the reliability and clinical utility of microneuromas as identified via in vivo confocal microscopy as the diagnostic biomarker for NCP.

Detailed description

Dry Eye Disease (DED) is a multifactorial disease of the ocular surface characterized by a loss of homeostasis of the tear film, and accompanied by ocular symptoms, in which tear film instability and hyperosmolarity, ocular surface inflammation and damage, and neurosensory abnormalities. Neuropathic corneal pain (NCP), an ocular and severe type of neuropathic pain describes patients with symptoms of ocular discomfort out of proportion with clinical signs. The lack of clinical signs observed by standard ophthalmic examination has resulted in underdiagnosis of NCP or misdiagnosis as dry eye disease. Thus, having a biomarker for NCP is critical to identify and treat these patients. No biomarker or clinical signs exists to identify NCP patients. Investigating corneal neurosensory abnormalities could help to diagnose NCP and potentially differentiate these patients from those with DED. In vivo confocal microscopy (IVCM) allows for real-time optical biopsies at a quasi-histological level, allowing for assessment of corneal nerves. IVCM non-invasive diagnostic imaging across NCP, DED, and healthy individuals will be analyzed to validate corneal microneuromas as a biomarker for NCP.

Interventions

In vivo confocal microscopy (IVCM) allows for visualization of the corneal structures at the cellular level, allowing for assessment of corneal nerves. With a magnification of 800 times, it makes it possible to detect and quantify changes in the epithelial layers and sub-basal nerve plexus.

Sponsors

National Institute of Neurological Disorders and Stroke (NINDS)
CollaboratorNIH
Tufts Medical Center
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

All Subjects: 1. 18 years of age or older 2. Ability to consent 3. Best corrected visual acuity of 20/40 or better in each eye Dry Eye Disease Group: 1. Chief complaint is ocular surface discomfort or dry eye disease, but subject reports no ocular pain on OPAS questionnaire 2. Symptoms lasting at least 3 months 3. Presence of at least two of the following within the same eye: 1. Anesthetized Schirmer score =/\< 10mm 2. Corneal staining of \>3/15 based on NEI scale 3. Tear break up time \< 10 seconds Neuropathic Corneal Pain Group: 1. Chief complain is ocular surface discomfort or dry eye disease 2. Symptoms lasting at least 3 months 3. All of the following in both eyes: 1. Corneal staining of less than or equal to 3/15 based on NEI scale 2. Tear break up time =/\> 10 seconds 4. Must have at least 25% peripheral pain 5. Subject reported discomfort prior to drop response testing of at least 3 out of 10 Control Group: 1. No symptoms of ocular surface discomfort or dry eye disease 2. All of the following in both eyes 1. Anesthetized Schirmer score \> 10 mm 2. Corneal staining of less than or equal to 3/15 based on NEI scale 3. Tear break up time \> 10 seconds 3. The same sex and within 5 years of age of a patient within the NCP group.

Exclusion criteria

1. Pregnant or nursing 2. Irregular corneal disease 3. Ocular surgery in the past 3 months 4. Ocular infection in the past 3 months 5. Active ocular allergies 6. Participation in a study that could potentially impact the IVCM in the opinion of the investigator 7. Current use of corneal nerve regeneration therapy that has been on-going for 3 months or more. 8. For NCP group only, patients for whom their pain and symptoms can be attributed to other causes in the opinion of the investigator

Design outcomes

Primary

MeasureTime frameDescription
Presence of microneuromas as assessed by in vivo confocal microscopy (IVCM).Day 1The obtained sequence of IVCM imaging scans of both eyes will be evaluated for findings of microneuromas; defined as either observed presence or absence of microneuroma

Secondary

MeasureTime frameDescription
Intra-subject repeatability; Presence of the microneuroma biomarker in the same participant at 2 weeksFrom Day 1 to 2 weeksConfirmation of presence of microneuroma on IVCM at 2 weeks in participants with IVCM finding of microneruoma at Visit 1
Establish the reference interval for the microneuroma biomarkerDay 1Quantification of microneuromas as assessed by IVCM in each cohort (Normal vs. NCP vs. DED)
Ocular Pain Assessment Survey (OPAS) questionnaire results correlation to microneuromas; OPAS reported quality of life score compared across the 3 cohorts.Day 1Ocular Pain Assessment Survey (OPAS) questionnaire: 27-item quantitative questionnaire designed to provide an assessment of the symptoms and quality of life effect of ocular pain. The 27 items of the OPAS questionnaire are graded on a scale of 0 to 10, or 10 to 100, where 0 indicates none and 10 or 100 indicate maximum. Higher scores indicate greater impact of ocular pain on quality of life dimensions.
Hyperosmolar functional nerve tests in correlation to microneuromas; hyperosmolar functional nerve tests results compared cross cohortsDay 1Using the Pain Visual Analogue Scale (VAS), Symptoms of ocular comfort and dryness at the time in question will be graded for each eye verbally on a scale of 0-10, where 0=excellent comfort, no dryness and 10=extremely uncomfortable, extremely dry. A single drop of hypertonic sodium chloride solution (Muro 128®, 5%) at room temperature will be instilled into each eye. After 20 seconds, participants will be asked to grade their ocular comfort and dryness symptoms as described in the VAS procedure again allowing assessment of changes in sensation due to the hyperosmolar drop and activation of the polymodal nociceptors
Test the utility of already configured AI software to diagnose NCP patientsDay 1 to 2 weekscategorical variables of NCP and DED as diagnosed by the AI system and the classification of subjects into the NCP and DED groups based on inclusion criteria set by the study

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026