Myopia
Conditions
Keywords
corneal reshaping therapy, corneal biomechanics
Brief summary
The aim of the proposed study is to investigate the predictive value of corneal biomechanical properties in corneal reshaping therapy and the role of these parameters in determining the amount of myopia reduction.
Detailed description
Experiment 1: To evaluate changes in corneal biomechanics caused by short-term corneal reshaping therapy. Subjects will wear a conventional RGP lens in one eye, randomly selected, and an orthokeratology lens in the fellow eye, for 30 minutes, 60 minutes and one night, respectively. Corneal stiffness and tangent modulus will be measured before and after each wearing period. Experiment 2: To evaluate changes in and the recovery of corneal biomechanics effected by long-term corneal reshaping and to assess whether corneal biomechanics can predict the rate of corneal reshaping. Subjects will wear orthokeratology lenses for 6 months. Regular follow up visits (1 week, 1 month, 3 months and 6 months) will be arranged to monitor the changes in corneal stiffness and tangent modulus.
Interventions
OTHERCorneal reshaping therapy
Reshaping the corneal curvature from wearing specific designed rigid gas permeable lenses
Sponsors
The Hong Kong Polytechnic University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* Myopia between -4D to -5D, with-the-rule astigmatism not more than 1.5D, spherical equivalent between -4D to -5.75D, difference between two eyes within 1D, best corrected spectacle visual acuity 0.10 logMAR in each eye
Exclusion criteria
* previous corneal reshaping therapy, long-term contact lens wear, ocular disease
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change of Corneal Stiffness From Baseline at 6 Months | At baseline, then change from baseline to 6 months | Corneal Stiffness: in N/mm Corneal parameters usually will stabilize in 1 month, this study will monitor it till 6 months. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change of Tangent Modulus From Baseline at 6 Months | At baseline, then change from baseline to 6 months | Tangent modulus: in MPa Corneal parameters usually will stabilize in 1 month, this study will monitor it till 6 months. |
Countries
Hong Kong
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Corneal Reshaping Therapy Participants receiving Corneal Reshaping Therapy were monitored for ocular biometry and refractive errors throughout a 6-month period. Corneal stiffness and tangent modulus were outcome measures. | 37 |
| Total | 37 |
Baseline characteristics
| Characteristic | Corneal Reshaping Therapy |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 37 Participants |
| Age, Continuous | 22 years |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants |
| Race (NIH/OMB) Asian | 37 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants |
| Race (NIH/OMB) More than one race | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) White | 0 Participants |
| Region of Enrollment Hong Kong | 37 participants |
| Sex: Female, Male Female | 30 Participants |
| Sex: Female, Male Male | 7 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 37 |
| other Total, other adverse events | 0 / 37 |
| serious Total, serious adverse events | 0 / 37 |
Outcome results
Primary
Change of Corneal Stiffness From Baseline at 6 Months
Corneal Stiffness: in N/mm Corneal parameters usually will stabilize in 1 month, this study will monitor it till 6 months.
Time frame: At baseline, then change from baseline to 6 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Treatment | Change of Corneal Stiffness From Baseline at 6 Months | 0.061 N/mm | Standard Deviation 0.007 |
Secondary
Change of Tangent Modulus From Baseline at 6 Months
Tangent modulus: in MPa Corneal parameters usually will stabilize in 1 month, this study will monitor it till 6 months.
Time frame: At baseline, then change from baseline to 6 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Treatment | Change of Tangent Modulus From Baseline at 6 Months | 0.536 MPa | Standard Deviation 0.118 |