Clinical trial NCT05758753: QST for Corneal Nerve Function
Official title: The Efficacy of Quantitative Sensory Test (QST) in Assessing Corneal Nerve Functions in Patients with Ocular Surface Diseases
Study type: INTERVENTIONAL
Overall status: ENROLLING_BY_INVITATION
Phase: NA
Conditions: Corneal Disease
Neuropathy
Dry Eye Disease
Neurotrophic Keratitis
Keywords: Quantitative Sensory Test
Lead sponsor: Tufts Medical Center
Sponsor class: OTHER
Collaborators: name: Dompé Farmaceutici S.p.A
First posted: 2023-03-07
Enrollment: 108
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: This study is designed to learn more about the impact different types of stimuli, such as heat, cold and vibration, can have on ocular pain response. This is called quantitative sensory testing (QST). Most procedures being performed in this study, except the QST, are standard of care which means they are performed during the participant's routine eye examination.

Detailed description: Quantitative Sensory Test (QST) is a non-invasive neurophysiological method that refers to a group of procedures that assess the perceptual responses to systematically applied and quantifiable sensory stimuli for the purpose of characterizing somatosensory function or dysfunction.

In this study, we propose to evaluate corneal nerve functions in patients with corneal nerve abnormalities by QST and correlate the nerve functions with symptoms, clinical signs and nerve morphology detected by In-Vivo Confocal Microscopy (IVCM). Identification of corneal nerve functions and correlations with other findings may help us to understand underlying pathological mechanisms of the disease and may guide us toward new treatment targets.

We hypothesize that, QST may provide us detailed information about corneal nerve function alterations and may correlate with morphological nerve changes detected by IVCM.

Eligibility criteria: Inclusion Criteria:

Group 1: Stage I Neurotrophic Keratopathy (NK)

1. Clinical findings of Stage I NK
2. Decreased nerve density by IVCM
3. Decreased corneal sensation

Group 2: Stage II NK

1. Clinical findings of Stage II NK
2. Decreased nerve density by IVCM
3. Decreased corneal sensation

Group 3: Dry Eye Disease (DED)

1. Symptoms of DED at least 3 months
2. Presence of at least one of the following DED signs; tear film break-up time lower than 7, ocular surface staining more than +1 based on NIH scale
3. Normal or mildly effected corneal sensation

Group 4: Healthy Individuals

1. Absence of any ocular surface symptoms
2. Absence of ocular surface findings
3. Transparent and clear cornea
4. Normal corneal sensation

Group 5: NCP

1. Presence of neuropathic symptoms AND
2. Symptoms out of proportion to clinical findings AND
3. Nerve abnormalities detected by in vivo confocal microscopy

Exclusion Criteria:

1. History of diabetes
2. History of ocular surgery, corneal infection, or corneal injury within the last 3 months
3. Systemic regular anti-inflammatory and/or steroid and/or immune-modulatory therapy in the last 3 months
4. Active ocular allergies
5. Any major psychiatric illness including bipolar, psychosis, obsessive-compulsive disorder and major depression
6. Pregnancy
7. History of surgery within the last 3 months
8. History of , sarcoidosis, GVHD or collagen vascular disease
9. Allergic to benzalkonium chloride "BAK" (an eye-drop preservative)
10. Concurrent enrollment in other studies that in the opinion of the investigator will interfere with the results of this study
11. Non-English speakers

Primary outcomes:
measure: Thermal stimulus response to QST on site of trigeminal nerve first branch, as assessed by cold detection threshold (CDT) and hot detection threshold (HDT)
timeFrame: From visit 1 up to 4 weeks
measure: Mechanical stimulus response to QST on site of trigeminal nerve first branch, as assessed by vibration detection threshold (VDT)
timeFrame: From visit 1 up to 4 weeks
measure: Differences in thermal stimulus pain threshold across the 4 study arms
timeFrame: From visit 1 up to 4 weeks
measure: Differences in mechanical stimulus pain threshold across the 4 study arms
timeFrame: From visit 1 up to 4 weeks
Secondary outcomes:
measure: To correlate the QST responses with morphological changes of corneal nerves detected by IVCM
timeFrame: From visit 1 up to 4 weeks
measure: To correlate symptom severity as assessed by the Ocular Surface Disease Index (OSDI), to stimulus response across the 4 interventional arms.
timeFrame: From visit 1 up to 4 weeks
measure: To compare QST response differences between trigeminal nerve first branch and forearm in patients.
timeFrame: From visit 1 up to 4 weeks
Other outcomes:
Locations:
city: Boston
country: United States
facility: Tufts Medical Center
state: Massachusetts
Study officials:
affiliation: Tufts Medical Center
name: Pedram Hamrah, MD
role: PRINCIPAL_INVESTIGATOR
References: