Brief Title
Corneal Biomechanical Changes of Allergic Conjunctivitis
Official Title
Corneal Biomechanical Changes and Related Risk Prediction in Allergic Conjunctivitis
Brief Summary
By measuring and comparing the corneal biomechanical parameters of normal people, patients
with allergic conjunctivitis, keratoconus, whether allergic conjunctivitis causes changes in
corneal biomechanics can be explored, and sensitive mechanical indicators of allergic
conjunctivitis can be identified. Furthermore, through rubbing frequency, ocular allergic
symptom scores and physical sign scores observation, corneal morphological parameters,
corneal epithelial thickness, tear inflammatory cytokines levels, and conjunctival
microvascular parameters measurements, related factors affecting corneal biomechanics in
patients with allergic conjunctivitis can be identified. Otherwise, by comparing corneal
biomechanical changes in vernal keratoconjunctivitis before and after drug treatment,
biomechanical change tendency during treatment can be clarified.
Detailed Description
The current study involves 3 parts. The first part aims to explore whether allergic
conjunctivitis causes changes in corneal biomechanics and to identify sensitive mechanical
indicators of allergic conjunctivitis. This part is a cross-sectional study. Four groups are
included: normal group, vernal keratoconjunctivitis (VKC) group, seasonal allergic
conjunctivitis (SAC) group and keratoconus (KC) group, with 25 eyes in each group (in normal
group one eye is randomly selected , and in VKC group, SAC group and KC group the more severe
one is selected). Patients in all groups meet inclusion criteria and voluntarily join this
study with informed consents. Medical history is collected, including basic information,
allergic history and course of disease. Corneal biomechanics is measured by Corvis ST. The
difference of corneal biomechanics among groups is analyzed to determine corneal
biomechanical changes of AC and to find sensitive mechanical indicators of AC.
The second part aims to identify related factors affecting corneal biomechanics in patients
with allergic conjunctivitis. This part is also a cross-sectional study. Four groups are
included: normal group, VKC group, SAC group and KC group, with 25 eyes in each group.
Medical history is collected, including basic information, allergic history and course of
disease. Eye rubbing frequency, ocular allergic symptom scores and physical sign scores are
measured and recorded in VKC group and SAC group. Corneal biomechanics measured by Corvis ST,
corneal morphological parameters measured by Pentacam, corneal epithelial thickness measured
by Optovue OCT, tear cytokine levels measured by Milliplex kit and conjunctival microvascular
parameters measured by functional slit lamp are performed in all patients. Correlation
analysis of corneal biomechanical parameters and other measurement indicators in VKC group
and SAC group is performed to determine the relevant influencing factors of corneal
biomechanics in AC.
The third part aims to determine corneal biomechanical change tendency during treatment in
VKC. This part is a prospective case-control study. 25 patients with 25 eyes (the more severe
eye is selected) are included. Medical history is collected, including basic information,
allergic history and course of disease. Eye rubbing frequency, ocular allergic symptom scores
and physical sign scores are measured and recorded in VKC group and SAC group. Corneal
biomechanics measured by Corvis ST, corneal morphological parameters measured by Pentacam,
corneal epithelial thickness measured by Optovue OCT, tear cytokine levels measured by
Milliplex kit and conjunctival microvascular parameters measured by functional slit lamp are
performed in all patients before drug treatment. And all the patients adopt a unified
medication regimen. The same ophthalmological examinations are performed again after 3 month
medication. Based on the analysis of the difference between the two measurements before and
after the drug treatment, corneal biomechanical change tendency during treatment in VKC is
clarified and the potential mechanical parameter needed to be monitored during follow-up is
identified. The specific therapeutic regimen is as follows: 0.1% tacrolimus eye drops four
times daily; 0.1% flumirone eye drops twice daily; azelastine hydrochloride eye drops four
times daily; hyaluronic acid sodium eye drops four times daily. After 1M, 0.1% flumilone eye
drops is replaced with 0.02% flumirone eye drops twice daily, and the rest of the medication
remaines unchanged.
Study Type
Observational
Primary Outcome
Corneal biomechanics
Secondary Outcome
Eye rubbing frequency
Condition
Conjunctivitis, Allergic
Study Arms / Comparison Groups
nomal
Description: Corneal biomechanics, corneal topographic parameters, corneal epithelial thickness, tear inflammatory cytokines levels and conjunctival microvascular parameters will be measured, and comparative analysis of biomechanics with other groups will be performed.
Publications
* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.
Recruitment Information
Estimated Enrollment
100
Start Date
November 10, 2019
Completion Date
June 30, 2021
Primary Completion Date
May 31, 2021
Eligibility Criteria
Normal group
Inclusion Criteria:
1. No abnormalities are found by slit lamp and Pentacam.
2. Diopters: diopter of spherical: -6.0D~+3.0D, diopter of cylinder: -2.0D~+2.0D,
spherical equivalent: -6.0D~+3.0D
3. Best corrected visual acuity ≥ 1.0
Exclusion Criteria:
1. Patients diagnosed with other eye diseases other than refractive error.
2. With a history of eye surgery or trauma.
3. With systemic diseases such as immune diseases and connective tissue diseases.
4. With a family history of keratoconus and glaucoma.
5. Wear soft contact lens within 2 weeks or rigid contact lens within 1 month.
SAC group
Inclusion Criteria:
1. Symptoms: Itching, foreign body sensation, increased discharge in conjunctival sac.
And children may mainly show an increase in blinking frequency.
2. Signs: conjunctival hyperemia, swelling, tarsal papillae.
3. Medical history: seasonal onset
4. Diopters: diopter of spherical: -6.0D~+3.0D, diopter of cylinder: -2.0D~+2.0D,
spherical equivalent: -6.0D~+3.0D
5. Best corrected visual acuity ≥ 0.8
Exclusion Criteria:
1. Corneal scar.
2. Other active inflammatory diseases of the eye.
3. With a history of eye surgery or trauma.
4. With systemic diseases such as immune diseases and connective tissue diseases.
5. Wear soft contact lens within 2 weeks or rigid contact lens within 1 month.
6. Unable to fixate and cooperate.
VKC group
Inclusion Criteria:
1. Symptoms: Itching, foreign body sensation, increased discharge in conjunctival sac.
And children may mainly show an increase in blinking frequency.
2. Signs: giant papillae on the upper tarsal conjunctiva and gelatinous infiltration of
the limbus.
3. Diopters: diopter of spherical: -6.0D~+3.0D, diopter of cylinder: -2.0D~+2.0D,
spherical equivalent: -6.0D~+3.0D
4. Best corrected visual acuity ≥ 0.8
Exclusion Criteria:
The same as SAC group.
Keratoconus group
Inclusion Criteria:
1. With a history of myopia and astigmatism
2. Best corrected visual acuity <1.0
3. At least 1 positive sign of the following is found by slit lamp examination: thinning
of the corneal stroma, a cone-shaped ectatic protrusion of the cornea, Fleischer ring
and Vogt striae.
4. Typical signs of corneal topography: central corneal power value of the anterior
surface >47D, central inferior/superior dioptric asymmetry >3D (within 3mm), central
dioptric asymmetry between two eyes >1D.
Exclusion Criteria:
The same as SAC group.
Gender
All
Ages
7 Years - 50 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Contacts
Jin Yuan, PhD, 86-018843014719, [email protected]
Location Countries
China
Location Countries
China
Administrative Informations
NCT ID
NCT04299399
Organization ID
2019045
Responsible Party
Principal Investigator
Study Sponsor
Zhongshan Ophthalmic Center, Sun Yat-sen University
Study Sponsor
Jin Yuan, PhD, Principal Investigator, Zhongshan Ophthalmic Center, Sun Yat-sen University
Verification Date
March 2020