Neurosensory Abnormalities in SymptomAtic Ocular Surface Patients (NASA)
Public ClinicalTrials.gov record NCT04838223. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
This study is designed to measure how common nerve abnormalities are within a group of patients who feel discomfort within their eyes.
Study identification
- NCT ID
- NCT04838223
- Recruitment status
- Suspended
- Study type
- Observational
- Phase
- Not listed
- Enrollment
- 1,000 participants
Conditions and interventions
Conditions
Interventions
- 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 Other
Other
Eligibility (public fields only)
- Age range
- 18 Years and older
- Sex
- All
- Healthy volunteers
- Healthy volunteers not accepted
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Jul 2, 2021 (Actual)
- Primary completion
- Dec 31, 2025 (Actual)
- Completion
- Jul 2026 (Estimated)
- Last update posted
- Jan 27, 2026
2021 – 2026
United States locations
- U.S. sites
- 16
- U.S. states
- 11
- U.S. cities
- 13
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| Canyon City Eye Care | Azusa | California | 91702 | — |
| Western University of Health Sciences | Pomona | California | 91766 | — |
| University of California at San Francisco - Francis I Proctor Foundation | San Francisco | California | 94143 | — |
| Bruce W. Carter VA Medical Center | Miami | Florida | 33125 | — |
| University of Illinois at Chicago | Chicago | Illinois | 60612 | — |
| Illinois College of Optometry | Chicago | Illinois | 60616 | — |
| Kannarr Eye Care | Pittsburg | Kansas | 66762 | — |
| University of Maryland | Baltimore | Maryland | 21201 | — |
| Tufts Medical Center | Boston | Massachusetts | 02111 | — |
| Korb & Associates | Boston | Massachusetts | 02215 | — |
| Midwest Vision Research Foundation at Prepose Vision Institute | St Louis | Missouri | 63128 | — |
| Ophthalmology Associates | St Louis | Missouri | 63131 | — |
| Vita Eye Clinic | Shelby | North Carolina | 28150 | — |
| SkyVision Centers | Westlake | Ohio | 44145 | — |
| Hospital of the University of Pennsylvania (Scheie Eye Institute Perelman) | Philadelphia | Pennsylvania | 19104 | — |
| Baylor College of Medicine | Houston | Texas | 77030 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT04838223, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Jan 27, 2026 · Synced Oct 18, 2026
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Open the official record
The complete public registry record, listed eligibility criteria, and available contact information for NCT04838223 live on ClinicalTrials.gov.