Dry EyeNASANCT04838223
Neurosensory Abnormalities in SymptomAtic Ocular Surface Patients (NASA)
An observational study of Dry Eye and Neuropathic Pain, run by Tufts Medical Center at 16 sites in United States.
Trial summary
This study is designed to measure how common nerve abnormalities are within a group of patients who feel discomfort within their eyes. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Dry Eye, Neuropathic Pain
- What is being tested?
- Hyperosmolar Response, Proparacaine Challenge Test and Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers
- How many people
- 1,000 participants
- Where
- 16 sitesUnited States
- Study dates
- 2 Jul 2021to Jul 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
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: 1,000 subjects will be enrolled for this study based on the above criteria:
Who may be able to join
- Presents with ocular surface discomfort or for dry eye care
- Best corrected visual acuity of 20/40 or better in each eye
- Subject reported duration of symptoms of at least 3 months
- 100 subjects will be required to be habitual contact lens wearers as defined by use of contact lenses at least 5 hours per day at least 5 days per week for the last year.
Who cannot join
- Use of contact lenses on the day of the visit
- Pregnant or nursing
- Irregular corneas (e.g., ectatic disease, transplantation, or corneal dystrophies)
- Ocular surgery in the past 3 months
- Ocular infection in the past 3 months
- Active ocular allergies
Trial locations and contacts
16 sites in 1 country.
16 sites in 1 country
United States16 sites
Canyon City Eye Care
Azusa, California, 91702
University of Maryland
Baltimore, Maryland, 21201
Tufts Medical Center
Boston, Massachusetts, 02111
Korb & Associates
Boston, Massachusetts, 02215
University of Illinois at Chicago
Chicago, Illinois, 60612
Illinois College of Optometry
Chicago, Illinois, 60616
Baylor College of Medicine
Houston, Texas, 77030
Bruce W. Carter VA Medical Center
Miami, Florida, 33125
Hospital of the University of Pennsylvania (Scheie Eye Institute Perelman)
Philadelphia, Pennsylvania, 19104
Kannarr Eye Care
Pittsburg, Kansas, 66762
Western University of Health Sciences
Pomona, California, 91766
University of California at San Francisco - Francis I Proctor Foundation
San Francisco, California, 94143
Vita Eye Clinic
Shelby, North Carolina, 28150
Midwest Vision Research Foundation at Prepose Vision Institute
St Louis, Missouri, 63128
Ophthalmology Associates
St Louis, Missouri, 63131
SkyVision Centers
Westlake, Ohio, 44145
About this study
This study is designed to measure how common nerve abnormalities are within a group of patients who feel discomfort within their eyes.
- Conditions
- Dry Eye, Neuropathic Pain
- Being tested
- Hyperosmolar Response, Proparacaine Challenge Test, Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers, Ocular Pain Assessment Survey (OPAS), Visual Analogue Questionnaire
- Medical subject headings
- Dry Eye Syndromes, Neuralgia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Hyperosmolar ResponseOther
A single drop of hypertonic sodium chloride solution at room temperature will be instilled in each eye and change in pain/other symptoms after up to 90 seconds of application (to account for any initial irritation symptoms) will be observed.
Proparacaine Challenge TestOther
A single drop of Proparacaine hydrochloride ophthalmic solution, (Alcaine®, 0.5%) will be used on each eye respectively and any change in pain/other symptoms will be noted after 90 seconds (to account for initial discomfort from the preservative in Proparacaine solution).
Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens WearersOther
The CLDEQ-8 is a validated eight-item scaled questionnaire developed to reflect the overall opinion of soft contact lenses.
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.
Visual Analogue QuestionnaireOther
Symptoms of ocular comfort and dryness will be graded for each eye on a scale of 0-10, where 0=extremely uncomfortable, extremely dry and 10=excellent comfort, no dryness. An average rating will be provided for the morning, afternoon and evening.
| Study group | Role | What they receive |
|---|---|---|
| Neuropathic Corneal Pain with Ocular Surface Discomfort | Participants diagnosed with neuropathic corneal pain with ocular surface discomfort Receives: Other: Hyperosmolar Response; Other: Proparacaine Challenge Test; Other: Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers; Other: 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 Receives: Other: Hyperosmolar Response; Other: Proparacaine Challenge Test; Other: Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers; Other: Ocular Pain Assessment Survey (OPAS); Other: Visual Analogue Questionnaire | |
| 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 Receives: Other: Hyperosmolar Response; Other: Proparacaine Challenge Test; Other: Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers; Other: Ocular Pain Assessment Survey (OPAS); Other: Visual Analogue Questionnaire |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 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.
Measured: 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.
Measured: Day 1
Secondary outcomes (4)
To assess the overlap of neuropathic corneal pain and contact lens discomfort.
Percent of contact lens wearers who report discomfort when wearing their contact lenses, and either do or do not exhibit signs of dry eye disease as defined by TBUT, Schirmer's test, and staining, and have an increase in VAS score of more than 2 steps upon instillation of hypertonic saline.
Measured: 1 study visit
To establish the prevalence of anxiety/depression in patients with neuropathic corneal pain patients.
Percent of subjects who report increased ocular surface discomfort upon challenge with hyperosmolar saline and a history of anxiety/depression.
Measured: Day 1
To assess for differences in in vivo confocal microscopy measures between dry eye disease patients and neuropathic corneal pain patients.
As measured by dendritic cell density, nerve fiber density, and microneuroma density
Measured: 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.
As measured by dendritic cell density, nerve fiber density, and microneuroma density
Measured: Day 1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Apr 2021
- Study start2 Jul 2021
- Primary completion31 Dec 2025
- Study completionJul 2026 (estimated)
Why it stopped: PI is leaving insitution. This study is no longer active at TMC.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Dry EyeStudies 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
- Other
- Time perspective
- Prospective
- Enrolment
- 1,000 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Tufts Medical Center
- Sponsor type
- University, hospital or other
- Collaborators
- CooperVision International Limited (CVIL), Bausch & Lomb Incorporated
- Responsible party
- Sponsor
- Investigators
- Pedram Hamrah, MD, Principal investigator, Tufts Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04838223
- Sponsor's protocol ID
- 00000319
- Acronym
- NASA
- Status last verified
- Jan 2026
- First submitted
- 19 Aug 2020
- Last updated
- 27 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Neurosensory Abnormalities in SymptomAtic Ocular Surface Patients (NASA)
- ClinicalTrials.gov ID
- NCT04838223
- Acronym / sponsor ID
- NASA / 00000319
- Conditions
- Dry Eye, Neuropathic Pain
- Study type
- Observational
- Recruitment status
- SuspendedReason stopped: PI is leaving insitution. This study is no longer active at TMC.
- Enrolment
- 1,000 participants (estimated)
- Lead sponsor
- Tufts Medical CenterUniversity, hospital or other
- Collaborators
- CooperVision International Limited (CVIL), Bausch & Lomb Incorporated
- Study start
- 2 Jul 2021 (actual)
- Primary completion
- 31 Dec 2025 (actual)
- Study completion
- Jul 2026 (estimated)
- First posted
- 9 Apr 2021 (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 study is designed to measure how common nerve abnormalities are within a group of patients who feel discomfort within their eyes.
Study design
- Observational model
- Other
- Time perspective
- Prospective
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Neuropathic Corneal Pain with Ocular Surface Discomfort | – | Other: Hyperosmolar Response, Other: Proparacaine Challenge Test, Other: Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers, Other: Ocular Pain Assessment Survey (OPAS), Other: Visual Analogue QuestionnaireParticipants diagnosed with neuropathic corneal pain with ocular surface discomfort |
| Neuropathic Corneal Pain with Dry Eye Disease | – | Other: Hyperosmolar Response, Other: Proparacaine Challenge Test, Other: Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers, Other: Ocular Pain Assessment Survey (OPAS), Other: Visual Analogue QuestionnaireParticipants diagnosed with dry eye disease and neuropathic corneal pain |
| NCP or Dry Eye in patients with ocular surface discomfort | – | Other: Hyperosmolar Response, Other: Proparacaine Challenge Test, Other: Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens Wearers, Other: Ocular Pain Assessment Survey (OPAS), Other: Visual Analogue QuestionnaireParticipants diagnosed with neuropathic corneal pain or with a neuropathic component of dry eye in patients with ocular surface discomfort |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- 1,000 subjects will be enrolled for this study based on the above criteria:
Key inclusion criteria (4 listed)
- Presents with ocular surface discomfort or for dry eye care
- Best corrected visual acuity of 20/40 or better in each eye
- Subject reported duration of symptoms of at least 3 months
- 100 subjects will be required to be habitual contact lens wearers as defined by use of contact lenses at least 5 hours per day at least 5 days per week for the last year.
Key exclusion criteria (6 listed)
- Use of contact lenses on the day of the visit
- Pregnant or nursing
- Irregular corneas (e.g., ectatic disease, transplantation, or corneal dystrophies)
- Ocular surgery in the past 3 months
- Ocular infection in the past 3 months
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 |
|---|---|---|
| Hyperosmolar ResponseA single drop of hypertonic sodium chloride solution at room temperature will be instilled in each eye and change in pain/other symptoms after up to 90 seconds of application (to account for any initial irritation symptoms) will be observed. | Other | NCP or Dry Eye in patients with ocular surface discomfort, Neuropathic Corneal Pain with Dry Eye Disease, Neuropathic Corneal Pain with Ocular Surface Discomfort |
| Proparacaine Challenge TestA single drop of Proparacaine hydrochloride ophthalmic solution, (Alcaine®, 0.5%) will be used on each eye respectively and any change in pain/other symptoms will be noted after 90 seconds (to account for initial discomfort from the preservative in Proparacaine solution). | Other | NCP or Dry Eye in patients with ocular surface discomfort, Neuropathic Corneal Pain with Dry Eye Disease, Neuropathic Corneal Pain with Ocular Surface Discomfort |
| Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) Optional; only for Contact Lens WearersThe CLDEQ-8 is a validated eight-item scaled questionnaire developed to reflect the overall opinion of soft contact lenses. | Other | NCP or Dry Eye in patients with ocular surface discomfort, Neuropathic Corneal Pain with Dry Eye Disease, Neuropathic Corneal Pain with Ocular Surface Discomfort |
| Ocular Pain Assessment Survey (OPAS)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. | Other | NCP or Dry Eye in patients with ocular surface discomfort, Neuropathic Corneal Pain with Dry Eye Disease, Neuropathic Corneal Pain with Ocular Surface Discomfort |
| Visual Analogue QuestionnaireSymptoms of ocular comfort and dryness will be graded for each eye on a scale of 0-10, where 0=extremely uncomfortable, extremely dry and 10=excellent comfort, no dryness. An average rating will be provided for the morning, afternoon and evening. | Other | NCP or Dry Eye in patients with ocular surface discomfort, Neuropathic Corneal Pain with Dry Eye Disease, Neuropathic Corneal Pain with Ocular Surface Discomfort |
Primary outcome
To establish the prevalence of neuropathic corneal pain in patients with ocular surface discomfort.
Time frame: Day 1
As measured by the percent of subjects who report increased ocular surface discomfort upon challenge with hyperosmolar saline.
To assess the overlap of neuropathic corneal pain with dry eye disease in patients in diseases that are currently thought to be mutually exclusive.
Time frame: Day 1
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.
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.
Time frame: Day 1
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.
4 secondary outcomes
To assess the overlap of neuropathic corneal pain and contact lens discomfort.
Time frame: 1 study visit
To establish the prevalence of anxiety/depression in patients with neuropathic corneal pain patients.
Time frame: Day 1
To assess for differences in in vivo confocal microscopy measures between dry eye disease patients and neuropathic corneal pain patients.
Time frame: 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.
Time frame: Day 1
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Jan 2026.
- Individual participant dataSharing planned: No
Related trials for Dry Eye
Not yet recruitingPhase 1
R-2487 in Patients With Sjogren's Syndrome (SjD)
Sjogren's Syndrome, Sjögren
RecruitingPhase 1
A Trial in Healthy Adult Participants and Adults With Autoimmune Diseases to Test How HBM7020 is Tolerated and How it Behaves in the Body
Rheumatoid Arthritis, Systemic Lupus Erythematosus
RecruitingObservational study
Pain Phenotyping of Rheumatic Diseases - An Observational Study
Rheumatic Diseases, Lupus Erythematosus, Systemic
RecruitingPhase 1/2
Autologous Transplantation of Induced Pluripotent Stem Cell-Derived Retinal Pigment Epithelium for Geographic Atrophy Associated With Age-Related Macular Degeneration
Dry Age-Related Macular Degeneration, Geographic Atrophy
RecruitingObservational study
The Pathogenesis and Natural History of Sjogren's Disease
Sjogren's Syndrome, Salivary Gland
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. This study is not recruiting at the moment.
Pedram Hamrah, MD principal investigator
Tufts Medical Center
16 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Dry Eye and Neuropathic Pain, run by Tufts Medical Center at 16 sites in United States.
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 4 inclusion and 6 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: paused, as of the sponsor's last update on 27 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 16 sites in United States. 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?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To establish the prevalence of neuropathic corneal pain in patients with ocular surface discomfort. (time frame: Day 1). 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 27 Jan 2026.