Brief Summary

This study is designed to measure how common nerve abnormalities are within a group of patients who feel discomfort within their eyes.

Trial Health

Monitor

Trial Health Score

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

Trial recruitment is currently suspended

Enrollment

1,000

participants targeted

Target at P75+ for all trials

Timeline

2mo left

Started Jul 2021

Longer than P75 for all trials

Geographic Reach

1 country

16 active sites

Status

suspended

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

5 years study duration

Study Progress97%

Jul 2021Jul 2026

First Submitted

Initial submission to the registry

August 19, 2020

Completed

8 months until next milestone

First Posted

Study publicly available on registry

April 9, 2021

Completed

3 months until next milestone

Study Start

First participant enrolled

July 2, 2021

Completed

4.5 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2025

Completed

6 months until next milestone

Study Completion

Last participant's last visit for all outcomes

July 1, 2026

Expected

Last Updated

January 27, 2026

Status Verified

January 1, 2026

Enrollment Period

4.5 years

First QC Date

August 19, 2020

Last Update Submit

January 23, 2026

Conditions

Neuropathic Pain Dry Eye

Outcome Measures

Primary Outcomes (3)

To establish the prevalence of neuropathic corneal pain in patients with ocular surface discomfort.
As measured by the percent of subjects who report increased ocular surface discomfort upon challenge with hyperosmolar saline.
Day 1
To assess the overlap of neuropathic corneal pain with dry eye disease in patients in diseases that are currently thought to be mutually exclusive.
As measured by the percent of subjects who report ocular surface discomfort, and either do or do not exhibit signs of dry eye disease as defined by Tear Break Up Time, Schirmer's test, and staining, and have an increase in Visual Analog Scale score of more than 2 steps upon instillation of hypertonic saline.
Day 1
To establish the prevalence of subtypes of patients with neuropathic corneal pain or with a neuropathic component of dry eye in patients with ocular surface discomfort.
As measured by the percent of subjects who report ocular surface discomfort, and have a decrease, partial decrease, or no change in Visual Analog Score score upon instillation of proparacaine.
Day 1

Secondary Outcomes (4)

To assess the overlap of neuropathic corneal pain and contact lens discomfort.
1 study visit
To establish the prevalence of anxiety/depression in patients with neuropathic corneal pain patients.
Day 1
To assess for differences in in vivo confocal microscopy measures between dry eye disease patients and neuropathic corneal pain patients.
Day 1
To assess for subtypes of neuropathic corneal pain differences in in vivo confocal microscopy measures between dry eye disease patients and neuropathic corneal pain patients.
Day 1

Study Arms (3)

Neuropathic Corneal Pain with Ocular Surface Discomfort

Participants diagnosed with neuropathic corneal pain with ocular surface discomfort

Other: Hyperosmolar ResponseOther: Proparacaine Challenge TestOther: Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens WearersOther: Ocular Pain Assessment Survey (OPAS)Other: Visual Analogue Questionnaire

Neuropathic Corneal Pain with Dry Eye Disease

Participants diagnosed with dry eye disease and neuropathic corneal pain

NCP or Dry Eye in patients with ocular surface discomfort

Participants diagnosed with neuropathic corneal pain or with a neuropathic component of dry eye in patients with ocular surface discomfort

Interventions

Ocular Pain Assessment Survey (OPAS)OTHER

Twenty seven-item quantitative questionnaire designed to provide an assessment of the symptoms and quality of life effect of ocular pain \[18\]. 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.