An observational study in Dry Eye Syndromes and Corneal Disease, sponsored by Tufts Medical Center. Suspended at 2 sites in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-01-07.
Sponsored by Tufts Medical Center · Observational
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.
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.
1,292 studies on the registry are indexed under Dry Eye Syndromes; 191 are open to participants now.
This study's planned enrollment of 438 is above the median of 90 across 171 observational studies indexed under Dry Eye Syndromes.
Browse Dry Eye Syndromes studies →Tufts Medical Center is the lead sponsor of 194 studies on the registry; 28 are open to participants now.
Of its 30 completed or terminated interventional studies of FDA-regulated products, 16 (53%) have results posted.
Counted across the registry records on this site, refreshed daily.
We will not be limiting the inclusion of the NCP or DED groups for this study. We will be recruiting from two Cornea Clinics in diverse large cities of Boston and Philadelphia. Thus, the sample collected from this group is expected to be representative of the population for each of these groups. We will be limiting inclusion of the control group to those age and sex matched controls as described above. This will allow for the conclusions drawn from this study to be more applicable in clinical practice. Without an age and sex matched control group, one could attribute differences in IVCM to these two variables instead of the disease(s).
All Subjects:
Dry Eye Disease Group:
Presence of at least two of the following within the same eye:
Neuropathic Corneal Pain Group:
All of the following in both eyes:
Control Group:
All of the following in both eyes
Exclusion Criteria:
Symptoms of ocular surface discomfort or dry eye disease for at least 3 months, supported by clinical exam findings. Reported quality of life is not effected by ocular pain.
Other: In vivo confocal microscopy (IVCM)
Symptoms of ocular surface discomfort or pain for at least 3 months, that are reported to have a significant impact on quality of life and ability to perform daily activities.
Other: In vivo confocal microscopy (IVCM)
No symptoms of ocular surface discomfort or dry eye disease.
Other: In vivo confocal microscopy (IVCM)
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.
Presence of microneuromas as assessed by in vivo confocal microscopy (IVCM).
The 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
Time frame: Day 1
Intra-subject repeatability; Presence of the microneuroma biomarker in the same participant at 2 weeks
Confirmation of presence of microneuroma on IVCM at 2 weeks in participants with IVCM finding of microneruoma at Visit 1
Time frame: From Day 1 to 2 weeks
Establish the reference interval for the microneuroma biomarker
Quantification of microneuromas as assessed by IVCM in each cohort (Normal vs. NCP vs. DED)
Time frame: Day 1
Ocular Pain Assessment Survey (OPAS) questionnaire results correlation to microneuromas; OPAS reported quality of life score compared across the 3 cohorts.
Ocular 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.
Time frame: Day 1
Hyperosmolar functional nerve tests in correlation to microneuromas; hyperosmolar functional nerve tests results compared cross cohorts
Using 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
Time frame: Day 1
Test the utility of already configured AI software to diagnose NCP patients
categorical 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
Time frame: Day 1 to 2 weeks
Plan to share: No
This study is suspended, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Tufts Medical Center